RnR Rounds Podcast

LEARNING OBJECTIVES:

What are the safety considerations for U/S guided Nerve Blocks (& other procedures)?
☙ Potential Complications of ANY injection (U/S guided or otherwise)
☙ infection
☙ perform under optimized sterile conditions
☙ damage to vessels, nerves or other structures
☙ reduced w/ U/S guidance
☙ pain (organic ± anxiety type pain - see Episode #003)
1. ignore pain and do injection with coaching
2. EMLA cream - may help to some degree with both pain types
3. sub dermal injection of lidocaine (or pretty much anything - saline in a pinch!)
☙ sub dermal injection seems to work by distending nerves in that area(?)
☙ onset of pain relief is generally much faster than onset of pharmacodynamics of lidocaine
☙ LAST (Local Anesthetic Systemic Toxicity)
☙ Toxic dose of LA (local anesthetic) depends on:
☙ specific LA selected
☙ whether mixed with other drugs (e.g. epinephrine)
☙ route of administration (e.g. SC vs IV)
☙ many other factors(*) depending on patient, not to mention their mass
☙ Toxicity Tables are important to know, but are wildly inaccurate in their estimations because of (*)
☙ Symptoms of LAST:
☙ peri-oral or tongue paresthesias
☙ metallic taste
☙ dizziness or lightheadedness
☙ drowsiness, disorientation
☙ dysrhythmias
☙ hypotension
☙ seizure -> coma -> death (final progression of most toxic pathways)
☙ Management of LAST:
1. stop infusion / ensure no further administration of any additional LA
2. maintain airway, provide O2, be prepared to intubate if unstable
3. give intralipid 20% (indicated for toxicity due to fat-soluble drugs such as LAs)
☙ load with 1.5 mL/kg over 60 seconds; repeat bolus q 5 mins until cardiac stability achieved
☙ switch to infusion of 0.25 mL/kg/hr
4. for seizures: benzo (e.g. midazolam 2mg IV q1-2 mins pn)
5. for cardiac arrest: you must reduce dose of epinephrine to < 1mcg/kg
☙ see Episode #024 for epinephrine mixing / dosing
☙ Consider if there are any "critical nerves" which could cause problems if blocked
☙ specifically, think of the phrenic nerves (and hemi-diaphragmatic paralysis)
☙ potential complication of brachial plexus nerve blocks
☙ especially: supraclavicular & infraclavicular brachial plexus blocks
☙ avoid these blocks in frail patients, or patients with respiratory disease / compromise
☙ avoid performing these blocks bilaterally
What do we need / how do we prepare for a U/S guided nerve block or other procedure?
1. have you confirmed Intralipid is available in your department, right now? (only for nerve blocks)
2. needle choice:
☙ depends on procedure / indication
☙ for very superficial procedures a "regular injection needle" (e.g. 22g, 1.5 inch etc)
☙ for most U/S guided procedures a spinal needle works better (e.g. 22g spinal needle)
☙ U/S procedure-specific needle (has notches along needle shaft to enhance resolution)
☙ for any needle, the more perpendicular it is to the U/S beam, the easier it will be visualized
3. will you connect syringe directly to the needle, or use a short piece of tubing to connect the two
☙ direct connection is simpler, you control the injection yourself,
☙ but weight of syringe may make fine movement more challenging
☙ short tubing can put syringe in hands of assistant and take weight off needle -> more finesse
4A. sterility of ultrasound probe:
☙ commercial probe cover, vs
☙ transparent adhesive dressing (e.g. used to cover IV site), wrapped over probe
4B. sterility of operator: mask + gloves are critical.
☙ wear a gown for high-risk procedures (e.g. central line), or based on local policy
5. if nerve block: LA dose
☙ choose short acting (e.g. lidocaine) vs long acting (e.g. bupivicaine) based on therapeutic goal
☙ e.g. quick procedure vs desire for longer acting analgesia
☙ concentration of LA:
☙ for U/S guided nerve blocks, generally higher concentrations are best.
☙ in contrast, use lowest concentration for freezing skin and non-nerve block procedures
6. consider adding an adjunct to LA
☙ e.g. dexamethasone 4mg (1mL) mixed in with nerve block dose
☙ may stretch duration of bupivicaine from ~4hrs to ~ 24hrs
7. ensure all air is purged from syringe / injection rig
☙ injection of microscopic amounts of air can destroy quality of ultrasound image
8. Room Setup:
☙ avoid having to rotate at all costs!
☙ best setup = linear arrangement: patient part is in front of you, ultrasound screen is above / beyond
☙ patient part is in front of you, ultrasound screen is above / beyond patient part
☙ should be able to look from needle to screen without having to move your head
☙ best to sit, arrange yourself in the most comfortable / ergonomic position to perform procedure
Bonus: Tips for optimization of Procedures & Nerve Blocks:
1. scout with the ultrasound first (before sterile)
☙ mark skin with probe position / insertion point using a heavy marker
2. freeze skin ± expected track with lidocaine
3. Discussion of Short Axis vs. Long Axis orientation: see Episode #007)
4. use small bolus (e.g. 0.5 mL of bolus) to confirm needle tip position once closing in on target
5. aim to create "halo" of fluid around target nerve (for nerve blocks)
☙ do not inject between nerve fascicles

PEARLS FROM DISCUSSION:

In undifferentiated shock, keep Anaphylaxis in the back of your mind.
☙ anaphylaxis be subtle / mimic other causes
Caution with giving IV Crystalloid & Have a Low Threshold for Vasopressors
☙ IVF can be harmful for certain types of shock (e.g. obstructive causes like PE)
☙ PoCUS will be of great assistance in making this decision!
☙ Early Vasopressors Options:
(I) norepinephrine (start) 0.1-0.2 mcg/kg/min (titrating for MAP target)
☙ may take considerable time to mix / program / administer, so in interim consider mixing:
(II) push-dose epinephrine, giving 10-20mcg q1-3 mins prn (titrating for MAP target)
(1) Inject 1mL (100mcg) of Cardiac Epinephrine (comes as 1mg/10mL, in a cardboard box)
☙ into 9mL of NS (e.g. pre-filled NS syringe) to create epi 10 (ten) mcg/mL (x 10mL)
(2) Inject 1mG of any concentration of Epinephrine
☙ into 1L bag of NS to create: epi ~1 (one) mcg / mL (x 1,000 mL)
RV "Cycle of Death":
In PE 2 pathological processes are creating ↑RV afterload (acute pulmonary hypertension)
(1) mechanical blockage from clot
(2) vasoconstriction of pulmonary vasculature 2º inflammation
Results in:
☙ less output from the RV => less preload for LV and less cardiac output overall
☙ RV ↑volume & ↑pressure (septal shift visible on PoCUS) => LV 'compression' -> even worse output
☙ less cardiac output => myocardial ischemia => even worse cardiac function (and cycle continues)
☙ RV is a "Perfusion Princess"
☙ check out podcast by Sara Crager https://emcrit.org/emcrit/right-heart-sara-crager/
What is the lesser of two evils?
(A) delaying potentially life-saving thrombolysis treatment to get CT confirmation (risking cardiac arrest)
(B) giving thrombolysis before gold-standard (CT) confirmation of PE (risking 'unnecessary' complications)
Answer: it depends on how sick (unstable) your patient is - you have to use your judgement!
Sodium Bicarbonate:
☙ at pH of 7.2 (or worse) one or more amps of bicarb may help reduce pulmonary hypertension
☙ caution giving bicarb if PaCO2 is elevated (poor respiratory compensation)
☙ additional CO2 during respiratory failure can cause transient worsening of respiratory acidosis!
☙ dosing: give 1 amp of Sodium Bicarb over 2mins or more

LEARNING OBJECTIVES:

Defining vs Targets for Shock:
DEFINITIONS:
☙ Despite our strong desire for black & white numbers, shock is a clinical diagnosis.
☙ look for signs of end-organ perfusion such as:
☙ brain - altered LOC, presyncope, seizure
☙ heart - chest pressure, SOB
☙ systemic - nausea; pale, cool, clammy skin
☙ kidneys - ↓ urine output, ↑Creatinine
☙ looks for signs of compensation:
☙ HR generally increases (if not beta-blocked)
☙ tachypnea
☙ cutoffs:
☙ SPB < 90 mmHg for adults (but shock at much higher numbers is possible.)
☙ for kids use a formula to estimate minimum acceptable SBP = (age x 2) + 70
    ☙ e.g.: for a 5 year old: (5 x 2) + 70 = 80 mmHg (minimum SBP)
TARGETS:
☙ target MAP (adults)
☙ MAP is a weighted average of SBP and DBP
☙ MAP = (SBP + (2 x DBP)) ÷ 3
☙ MAP targets vary, but typically 65 mmHg is a good conservative starting place
☙ for kids: less of a precise number / more of:
☙ normalization of vital signs
☙ reversal of clinical signs of shock
Classifying Shock:
1. Cardiogenic Shock (Pumps Problem)
☙ electrical problems - dysrhythmia, tachycardia+++
☙ muscular problems - myopathy, myocarditis
☙ "fuel" problem - myocardial ischemia
☙ flow dynamics problem - valvulopathy, air lock / thrombus
☙ Solution:
☙ depends on specific etiology,
☙ IV Fluid bolus - can WORSEN certain subtypes (think RV dysfunction)
☙ investigate, tread cautiously, low threshold to seek advice / consultation.
2. Hypovolemic Shock (Fluid Problem)
☙ blood related - hemorrhagic shock, subacute anemia+++
☙ non-blood related:
☙ dehydration
☙ GI losses
☙ burns
☙ 3rd Spacing
☙ Solution:
☙ replace with crystalloid (ideally more balanced like Ringer's), or blood products
3. Distributive Shock (Pipes problem -- systemic / venodilatory)
☙ anaphylaxis
☙ sepsis
☙ neurogenic shock (spinal cord injury)
☙ Solution:
☙ venous pooling - vasopressor required:
☙ i.e. norepinephrine
☙ start at 0.1-0.2 mcg/kg/min, then double or half as you zero in on ideal dose
☙ good starting order?
☙ norepinephrine 0.1 mcg/kg/min titrate range between [0.02 - 1] q5mins to target MAP 65-70
4. Obstructive Shock (Pipes problem - cardio-pulmonary / poor flow)
☙ cardiac tamponade
☙ tension pneumothorax
☙ pulmonary embolism
☙ Solution:
☙ needle drain PCE (pericardial effusion)
☙ needle decompress PTX
☙ anticoagulate ± thrombolyze PE
Diagnosing Shock:
☙ Hardest Part of shock management (treatment is easy when cause of shock is known)
☙ needs to be a priority and executed quickly
Where History is useful:
☙ recent:
☙ recent illness
☙ recent GI losses
☙ recent trauma
☙ recent surgery
☙ relevant PMHx:
☙ known CAD, AAA, Marfan's etc
☙ symptoms: e.g. SOB
Physical Exam utility is limited:
☙ e.g. Sensitivity Beck's Triad (for tamponade) is terrible. (0-50% sensitive)
☙ https://europepmc.org/article/MED/28123617
☙ see Episode 018 for more examples of very limited reliability of physical exam (lung assessment)
Adjuncts are better!
☙ EKG -> cardioversion required? Rate suppression required? (> 120-150bpm?) STEMI?
☙ labs -> delayed but helpful if patient survives long enough
☙ CXR -> obsolete if basic lung PoCUS is possible
RUSH Exam (Rapid Ultrasound in Shock & Hypotension)
☙ designed to be completed in 1-3 minutes.
☙ it's components are quick screens looking for major shock causes
☙ don't do a full echo or FAST etc, just enough to get Y/N answers as below.
☙ For RUSH Exam, remember: HI-MAP
☙ Heart:
☙ PCE? -> tamponade until proven otherwise, so drain it!
☙ RV Pressure Overload? (Obstructive Shock - put PE high on DDx, consider searching for DVT)
☙ 50% of PEs have DVT as source, so find the DVT in this context and you have your answer
☙ LV Function?
☙ "normal function" --> when MAP is > 65, rules out significant cardiogenic shock
☙ "hyperdynamic" (poor filling) --> continue exam to sort out why there is poor LV preload
☙ "reduced ejection" (poor squeeze) --> screams cardiogenic shock / ?inotropes needed
☙ IVC:
☙ flat / collapsing IVC -> hypovolemic shock vs distributive shock (use your doctor hat)
☙ some IV fluid is indicated (pressure bag, not pump @ 999mL/hr)
☙ consider trial of vasopressors to reduce venous pooling
☙ normal IVC -> IV fluid will likely be tolerated (but not necessarily indicated)
☙ distended IVC -> think obstructive or cardiogenic shock. Halt IV fluid administration
☙ Morrison's Pouch:
☙ if positive: fluid (or blood) loss into abdomen. Trauma? Ruptured AAA? Ectopic? (etc)
☙ no need to look in all 6-7 windows of traditional FAST scan.
☙ if Morrison's is negative for fluid, intra-abdominal fluid loss is not significant source of shock
☙ Aorta:
☙ is there a AAA present? --> call vascular surgery and stabilize for transport
☙ ⅓ of AAA's rupture into retroperitoneal space (no free fluid seen on FAST scan)
☙ Pulmonary:
☙ is there a PTX (pneumothorax)? -> tension PTX until proven otherwise, so needle it!
Pearls to Remember:
1. When managing shock, time matters.
☙ Be aggressive and decisive in order to stabilize the MAP & reverse underlying causes
2. Be weary of Sepsis, Anaphylaxis & Cardiogenic shock - they can be masked!
☙ low threshold to treat with antibiotics, epinephrine & cardiac support / resus
3. Vasopressors are life-saving.
☙ give them early (e.g. push dose epinephrine 10 - 20 mcg IV bolus)
☙ give midrange doses (e.g. start norepinephrine 0.1 - 0.2 mcg/kg/min)

Episode 021 (Part A)

How does one manage [in a rural ER] a Severe/Refractory RAD Exacerbation? (PART A)
☙ Bronchodilators (salbutamol / ipratropium)
☙ salbutamol - first and primary step in managing RAD has 3 methods of administration
1. MDI + spacer (e.g. Aerochamber®) 2 - 15 sprays for severe bronchospasm
☙ MDI is most effective BUT requires cooperative patient with ability to breath-hold
☙ NOT so effective when patient is in extremis (bronchospasm group poorly studied)
☙ lower risk of spread of respiratory pathogens
☙ can be used "in-line" in intubate patient (timing and circuit/MDI adaptor required)
2. nebulizer 5mg / nebule (adults)
☙ higher risk of spread of respiratory pathogens (PPE / Isolation considerations)
☙ potentially better (continuous) exposure of salbutamol molecules to respiratory tissues
☙ significant benefit in extreme bronchospasm cases:
☙ where respiratory tree is closed and must be "gently peeled open"
3. intravenous 250 mcg - 1.25mg IV bolus (adults)
☙ bonafide "IV-approved" salbutamol doesn't exist(?)
☙ safe and effective to use nebulizer-salbutamol liquid
☙ education of nursing and other colleagues may be required
☙ may have to do this yourself.
☙ salbutamol nebule comes as 2.5mg in 2.5mL
☙ 2.5mg = 2,500mcg. Therefore, for 250mcg, draw up 1/10th of nebule
☙ give as IV push (chase with a normal saline syringe flush)
☙ if no response repeat with double last dose q 30-60 seconds
☙ anticipate tachycardia and significant improvement of bronchospasm within 30-60 seconds
☙ ipratropium 500mcg / nebule
☙ indicated in COPD exacerbation
☙ "continuous nebulization" with salbutamol:
☙ e.g. salbutamol 2.5mg + ipratropium 500 mcg (combined in single nebulizer chamber)
☙ no known harm in asthma exacerbation, so low threshold to administer for severe bronchospasm

Episode 022 (Part B)

(Con't) How does one manage [in a rural ER] a Severe/Refractory RAD Exacerbation? (PART B)
☙ steroids
☙ "Tier 2" priority (after bronchodilators are given)
☙ onset is 4-6 hours, so "early" administration is important
☙ but you need to continue to support the patient for a long time until steroids begin to work
☙ type of steroid / dose choice is not as critical as early administration
☙ IV is generally easier than PO administration in dyspneic patients
☙ not worth agonizing over "flavour" or exact dose of steroid
☙ methylprednisolone 2mg/kg is one example of a recommended dose
☙ Magnesium Sulphate 2g IV over 20 mins
☙ poor evidence to suggest a weak benefit
☙ consider giving if you have exhausted everything else (don't lose time on giving MgSO4)
☙ Heliox
☙ unlikely available outside major hospitals with dedicated RTs available
☙ if available discuss with / defer to expertise of RTs
☙ Ketamine 0.1mg/kg aliquots for sedation / compliance; 2mg/kg induction
☙ a powerful bronchodilator making ketamine a great choice if analgesia / sedative desired
☙ think of ketamine when considering Respiratory Support or Intubation
☙ Respiratory Support options:
☙ Non-invasive (e.g. Bag-Valve-Mask or BiPAP)
☙ use to supplement patient's respiratory efforts
☙ generally tolerated poorly, especially by dyspneic patient
☙ consider sedation - in particular ketamine (see above)
☙ Invasive (intubation)
☙ hold off and work with Non-Invasive and other treatments as long as safely possible
☙ consider intubation when patient is diaphoretic or unable to speak in short sentences
☙ RAD requires long (excessive) exhalation times
☙ if using a ventilator (or BiPAP), increase expiration time (or I:E ratio)
☙ if inadequate expiration time, "breath stacking" will occur
☙ i.e. increasing lung volume with each breath leading to pneumothorax if not released
☙ 6-8 seconds of expiration time (or I:E ratio of 1:4 or more) are often required
Underscore the importance of being maximally aggressive in Rural Resuscitation
☙ There are a handful of conditions in Emergency Medicine where seconds (not just minutes) can actually make a difference:
☙ cardiac arrest (time to CPR, defib, etc)
☙ anaphylaxis (time to epinephrine)
☙ tension PTX (time to needle decompression)
☙ profound cardiogenic shock / depression (time to normalization of minimum MAP)
☙ massive hemorrhage (time to bleeding control)
☙ massive PE (time to thrombolytics)
☙ undifferentiated shock (time to diagnosis & correction)
☙ RUSH Exam (Rapid Ultrasound in Shock & Hypotension)
☙ catastrophic ventilator problems
☙ CICO - Can't Intubate, Can't Oxygenate (time to crichothyrotomy)
☙ Severe / Refractory RAD (see above)
☙ etc.
☙ Key is to act swiftly and aggressively to resolve each. If you are not familiar and comfortable with the IMMEDIATE actions (including weight-based doses) to take with each of these, then:

(1) create your own "queue-card system" which you will be able to access immediately, while you work. There are plenty of FOAM resources available to assist in this process, but it takes significant time and thought.

OR

(2) purchase the Resuscitation Crisis Manual -- reference book purpose built with this problem in mind.
☙ if ordering for your self, get the North American Edition (units most-consistent with Canada)
☙ I carry a print copy in my bag as I personally phone-references cumbersome to read and navigate.

Note:
- participants of our Live or Virtual RnR Rounds Sim Program receive a copy of this book.
- RnR Rounds, RnR Rounds Podcast and Contributors have no financial interest in this publication.

LEARNING OBJECTIVES:

1. What does a Botulism exposure look like, and how is it managed?
☙ 3 types of botulism:
1. infantile botulism
2. food-borne botulism (more common in young children)
3. wound-botulism
☙ Typical Symptoms:
☙ descending paralysis
☙ respiratory muscle weakness (subtle or progressive), advancing rapidly to respiratory failure
☙ nausea / vomiting / dysphagia
☙ diplopia
☙ mydriasis / fixation of pupils
☙ dry mouth unrelieved by drinking water
☙ Management:
☙ rapid treatment with anti-toxin (located at Provincial Capitals usually?)
☙ supportive care
Reference: https://emedicine.medscape.com/article/213311-overview
2. How do we optimally sedate someone who is intubated, in preparation for medical transport?
☙ if you know what the transport team will want to use, consider using that
☙ proven standby: morphine & midazolam
☙ morphine 100mg + midazolam 100mg, together into 100mL IV bag (e.g. NS)
☙ initiate at 0.1mL/kg/hr (if vital signs are robust)
☙ reduce initial rate by 25-50% or more if patient is elderly, frail or hypotensive, etc.
☙ titrate to effect, anticipating 15-20 minutes before results of adjustment take effect
☙ regardless of sedation cocktail, have a ultra-short-acting "rescue" syringe next to the patient at all times
☙ e.g. propofol 20mL syringe
☙ for use if patient becomes agitated or bucking the ventilator
3. Collegiality and Constructive Criticism
☙ Understand the difference between constructive criticism (supportive, education), vs non-constructive criticism (malicious, demeaning, toxic).
☙ engage in constructive criticism / confirmation regularly!
☙ don't hesitate to ask colleagues questions, confirm mutual understanding or propose alternate ideas
☙ more brains, especially from new angles are beneficial
☙ be cautious not to interfere with, criticize or bully a colleague
☙ different professions can have different levels of education / different intrinsic requirements
☙ asking questions to promote understanding is healthy.
☙ openly criticizing or demeaning a colleague (or their professional requirements), is oppression
☙ speculation about a professional's actions when they are not present is gossip and unprofessional
☙ influencing or pressuring a co-worker to make a decision differently may be coercion

☙ these sorts of negative behaviours may potentially lead to disciplinary action in most Canadian health authorities, if not legal repercussions.
☙ In any case, these negative behaviours have the potential to be psychologically damaging to the health care team, lead to poor decision making for patient care, worsen patient outcomes and otherwise turn a work place toxic.

☙ Always communicate in a supportive, professional manner. Maintain confidentiality. Play nicely.

LEARNING OBJECTIVES:

#1 Challenge a Rural Physician may face When Needing to do a HALO Procedure
☙ Fighting our own internal insecurity, and tendency for denial / procrastination!
☙ HALO (High Acuity, Low Opportunity) procedures frequently trigger a stress response
☙ e.g. Cardioversion, chest tube, initiating CPR (is there really no pulse?)
☙ causing us to second guess ourselves,
☙ or attempt to subconsciously talk ourselves out of an intervention which we know is indicated.
☙ For many Rural Doctors, often the hardest part of any HALO procedure is making the call to act now.
☙ Sit down with a coffee and analyze your own Critical Thinking Biases
☙ Every human has them, but if you're aware of yours then you're much closer to controlling them!
https://sjrhem.ca/wp-content/uploads/2015/11/CriticaThinking-Listof50-biases.pdf
My own approach to a rural cardioversion
Assuming: EKG / investigations already obtained urgent cardioversion required
☙ e.g. unstable due to chest pain, shortness of breath, dizziness, etc
☙ give thought to need for anticoagulation:
☙ rhythm is potentially thrombogenic (e.g AFib)
☙ consider risk of delaying cardioversion i.e.
a. risks of prolonged dysrhythmia (unstable or stable?) versus
b. risks of thromboembolism due to more urgent / timely cardioversion
1. "IOM" - IV, O2, Monitors (in an appropriate care area e.g. resuscitation room)
2. Prepare for procedural sedation (see also: 003 Ankle # Reduction)
3. Prepare for cardioversion (defib pads + cardiac sensing leads)
☙ decide on initial energy setting ± progression
☙ e.g. 200J for AFib vs 50J -> 100J -> 200J for "organized rhythms" (e.g. AFlutter, SVT)
4. Review plan with Team
5. Sedate and cardiovert.
☙ e.g. plan 50mg for healthy, spry adults, reduce for frail or elderly
☙ titrate with 10mg aliquots q 30sec to achieve heavily slurred speech
☙ cardiovert as pre-planned
Post-Cardioversion:
☙ consider need for cardiology referral (urgent / elective)
☙ consider need for anticoagulation or rate or rhythm control agent
Review of Demand Ischemia
☙ Demand Ischemia arises when myocardial muscle's O2 demand > O2 supply
☙ Factors increasing myocardial O2 demand (requirements) "VO2":
☙ elevated heart rate (i.e. tachycardia)
☙ squeezing harder (i.e. increased SVR - systemic vascular resistance = ↑B/P)
☙ Factors decreasing O2 supply (delivery) "DO2":
☙ ↓preload (i.e. hypovolemic shock, distributive shock)
☙ valve failure limiting forward flow (e.g. stenosis) or preventing back flow (e.g. regurgitation)
☙ myocardial muscle problems (e.g. myocarditis, infarct)
☙ ↑afterload is greater resistance to forward flow of blood (e.g. ↑B/P)
☙ insufficient time for heart to fill between contractions (e.g. tachycardia)
☙ further impacted of loss of organized atrial contraction (e.g. atrial fibrillation)

LEARNING OBJECTIVES:

Describe the diagnostic accuracy of CXR & Ultrasound for common lung pathologies.  
Appreciate the common ultrasound-artifacts consistent with dry vs wet lungs:
☙ A-lines
☙ B-lines
and well as other pathological changes:
☙ sub-pleural changes
☙ hepatization

This episode is a case-presentation. Please refer to Show Notes from:

Episode 009 Difficult Airway

LEARNING OBJECTIVES:

Build your own Anesthetic-Drug Table using Desirable Qualities vs Undesirable Qualities, etc.
☙ Desirable: analgesia, anesthesia, amnesia/sedation, muscle relaxation
☙ Undesirable: apnea, hypotension
☙ Clinically Useful info: onset, duration, dosing
See sample table below, but don't just copy it. Use it as a reference and build your own.
☙ You'll learn more and retain more if you do!
Evaluate Balanced-Cocktails using your table:
Procedural Sedation:
☙ Fentanyl + Midazolam (C+)
+ good therapeutic effect
-- high risk of apnea ± hypotension
-- not super-titratable as both drugs are medium duration.
☙ Ketamine + Propofol (A) (see episode 3)
+ good therapeutic effect
+ low risk of apnea ± hypotension
+ very titratable
Induction for Intubation:
☙ Ketamine + Succinylcholine (B+)
+ good therapeutic effect
+ easy dosing to remember at 2am (ketamine 1.5mg/kg, succinylcholine 1.5mg/kg)
+ rapid onset
+ relatively respiratory-stable (sux wears off in 8 min) in the event you Can't Intubate Can't Ventilate
+ relatively cardiovascularly stable (if patient is not adrenergically depleted.)
-- need suction handy for relatively common hyper-secretion (side effect of induction-dose ketamine)
Post-Intubation Sedation:
☙ Morphine + Midazolam (B+)
+ good therapeutic effect
+ easy dosing to remember at 2am (morph 100mg + midaz 1mg/mL into 100mL)
☙ start at 0.1mL/kg/hr and titrate for sedation / blood pressure
+ requires only one pump / one IV port to maintain infusion
+ relatively reversible in a crunch
+ avoids paralytic infusion (paralytics beyond intubation lead to worse ICU outcomes)
-- slow to titrate (keep a syringe of propofol at the bedside for use if the patient requires rapid top-up

LEARNING OBJECTIVES:

What to do with CSF once you've collected it?
☙ Generally collect 4 tubes in specific order, aiming to have ≥ 1mL per tube
☙ Tube for Cultures should ideally have more (e.g. 3-4mL of CSF if possible)
☙ Minimum volumes of 0.5mL are required even in low-flow situations in order to analyze
☙ Orders may vary depending on LP's indication, but in general:
Tube 1. cell count (initial)
Tube 2. protein, glucose, any other speciality tests
Tube 3. cultures
Tube 4. cell count (final)
☙ difference between Tube (1) & (4) will help determine extent of "traumatic tap"
How to prevent vasovagal during LP:
☙ mild sedation e.g. midazolam 0.5 - 1mg IV
☙ use lots of local anesthetic to mitigate sensations arising from the skin and soft tissues.
☙ perform LP in lateral decubitus (vs sitting)
☙ have patient distracted by a dedicated person (e.g. RN)
☙ if patient reports they are not feeling well - STOP.
☙ do not persist, even if they ask you too - you will regret it!
Testing Threshold - Does ordering a specific test introduce more RISK or BENEFIT?
Dangerous Attitudes in Medicine:
☙ "Better safe than sorry."
☙ "If you think about _____, you should do _____."
There is a major cognitive bias in [emergency] medicine whereby we often fail to recognize the magnitude of risk and potential complications from tests / procedures that we perform.
☙ radiation from 2-3 abdominal scans gives the same amount of radiation exposure that survivors of the Hiroshima nuclear bombing received
☙ 1.5% to 2.0% of all cancers in the United States may be attributable to the radiation from CT examinations (1,2)

Testing Threshold = The point at which ordering a test causes more harm than good.
e.g. we are more likely causing harm ordering a D-dimer if the probability of PE is < 2%
☙ i.e. the pre-test probability (which can be calculated with e.g. PERC score) is < 2%
☙ if risk of PE is < 2%, then the risk of D-dimer + related tests that may be obligated to follow (e.g. CT-PA) out weigh < 2% risk of missing a PE.
☙ e.g. risk of CT-PA in 20y/o female causing cancer (e.g. decades later) is ~ 1/330
☙ scan same patient's abdo for "abdo pain NYD" and risk is 1/500
☙ additive risk of causing cancer is now at 1/200 -- that should scare all of us!

At the very least we should ask: do we really need this CT right now, or is there an alternative option?

Alternative to CT for ?PE or "abdo pain NYD":
☙ perform PoCUS to rule out DVT
☙ 50% of PE's originate from DVT and if a DVT is present ➔ initiate treatment covering both (No CT.) ☙ perform PoCUS to assess:
☙ appendicitis -> surgeon
☙ giant ovarian cyst -> diagnostic ultrasound + gyne consult
☙ (etc)
☙ find nothing that correlates with pain (normal abdomen, no secondary signs of inflammation)
☙ is it safe to observe / reassess
☙ observe / reassess as inpatient vs outpatient
And yes! Sometimes CT is the most appropriate next step, in which case it should be ordered.
☙ but why not consider lower-risk alternates such as PoCUS ± serial reassessment?
☙ both PoCUS & admission have extremely low risk profiles ➔ more favourable risk/benefit ratios.

Testing Threshold for LPs:
Potential Complications:
☙ CNS infection
☙ Nerve / Vascular injury
☙ spinal cord hematoma
☙ vasovagal & associated injuries
☙ post-dural-puncture headache
These are not "High Risk" complications if an LP is performed carefully, but they are not insignificant.
☙ a diligent physician will use their knowledge and experience to weigh benefits / risks of LP for a given clinical situation. (No more knee-jerk reactions!)
☙ There won't always be a validated statistical prediction tool to help,
☙ but your intuition as a physician is much better than an over-investigation / shot-gun work-up.
☙ LP for a suspected CNS infection (e.g. convincing meningeal symptoms)
☙ probably most common rural LP indication
☙ LP for SAH - very narrow window for when LP is indicated (i.e. when benefits of LP-SAH > risks)
☙ https://first10em.com/subarachnoid-hemorrhage-lp/

The days where "if you think of something, you just go ahead and order it" should be long gone. Rather we should begin to educate ourselves about the hidden risks of more invasive diagnostics and procedures, and weigh them strategically against the risk level of the patient in front of us. It is a little more work, it requires a different way of thinking, but in the end we are going to do a lot less harm than what we are [conventionally] doing right now, and which is very poorly recognized and rarely talked about.

Ultrasound Fellowships compatible with Rural Practice (no need to move to a city / pause your job)
(1) pocus.rnrrounds.ca target audience = Canadian rural / remote physicians
(2) ultrasoundleadershipacademy.com target audience = full time emergency physicians

References:
(1) Brenner DJ, Hall EJ. Computed tomography—an increasing source of radiation exposure. N Engl J Med. 2007;357:2277-84.
(2) Berrington de González A, Mahesh M, Kim KP, et al. Projected cancer risks from computed tomographic scans performed in the United States in 2007. Arch Intern Med. 2009;169:2071-2077.

LEARNING OBJECTIVES:

Indications & Contraindications for an LP in a rural ER
☙ Indications:
1. Infusion of anesthetic (SAB), chemotherapy, or contrast agents into the sub-arachnoid space
2. Diagnosis of central nervous system (CNS) infection ** most common reason in Rural(?)
3. Diagnosis of subarachnoid hemorrhage (SAH) ** narrow indication window
4. Treatment of idiopathic intracranial hypertension
5. Evaluation and diagnosis of demyelinating or inflammatory CNS processes
☙ https://elentra.healthsci.queensu.ca/assets/modules/lumbar_puncture/indications.html
☙ Contraindications:
1. Skin infection near the site of the lumbar puncture
2. Suspicion of increased intracranial pressure due to a cerebral mass
3. Uncorrected coagulopathy -- ASA is safe; anti-platelet agents/anti-coagulants = relative C/I.
4. Acute spine trauma
☙ https://elentra.healthsci.queensu.ca/assets/modules/lumbar_puncture/contraindications.html
What other things need to be done around an LP, and in what order?
1. Have an IV in place. (IV fluid and/or sedation -- likely a generic requirement for resus anyway?)
2. ?Anxiolytic
e.g. midazolam 0.5-1mg IV -- need patient to be relaxed and cooperative, not sedated.
3. ?CT Scan or PoCUS: ONSD Scan (Optic Nerve Sheath Diameter)
☙ ?indicated to R/O elevated ICP (intracranial pressure)
☙ ONSD Scan = 96% sensitive / 92% specific(!)
☙ PoCUS is a great radiation-free alternative to CT
☙ but especially if obtaining a CT requires inter-hospital transfer
☙ https://pubmed.ncbi.nlm.nih.gov/30019201/
4. Antibiotics (for sepsis / ?meningitis)
☙ don't significantly delay antibiotics for an LP (or other cultures)
☙ Abx are the life-saving intervention so if in doubt give them
☙ but if you can prioritize cultures and LP, and obtain them quickly, do so to improve C&S value.
☙ non-evidenced base suggestion: don't delay Abx > 30 minutes to obtain cultures in ?sepsis.
☙ Just give them in this case, but still draw cultures / LP during / afterwards and ASAP.
How to perform a Lumbar Puncture:
a. Are you going to sit the patient (easier managing lateral spine alignment), or lie them in lateral decubitus (lower risk of vasovagal, weaker patients, can obtain opening pressure)
☙ opening pressure (O.P.): determines actual intracranial pressure (in cmH20)
☙ patient must be lying (sitting up ⇒ increased pressure due to gravity pulling on intracranial CSF)
☙ connect 3-way stopcock to "upright" graduated cylinder / pipette, and to spinal needle (in CSF)
☙ CSF will enter stopcock and climb pipette. Where fluid level stops (cm) = pressure in cmH2O
☙ not sure how O.P. is helpful in rural resuscitation but neurologists (etc) might value this info?
b. Position Patient
☙ curl the patient's back (slouching position)
☙ arc back into shape of the rainbow (peak of arc at the lumbar area)
☙ if sitting: give pillow to hug ± table to lean on for support ± footstool to elevate feet / knees
☙ if lateral, position shoulder on top of shoulder and hip on top of hip in near-fetal position
☙ take your time to position correctly - this is a CRITICAL STEP
c. Elevate bed so you can stand comfortably without stooping. Place equipment tray in an ideal location.
optional: Scan anatomy & mark with sharpie prior to sterilization
d. PPE
☙ mask is most important: reduce risk of causing meningitis
☙ sterile gloves
☙ ± gown, eye shield, etc, as appropriate
e. Sterilize back:
☙ chlorhexidine in 30x30cm square minimum,
☙ paint area twice with smaller inner square
☙ leave to dry on its own for minimum of 3 mins
f. Prepare equipment during chlorhexidine dry time
☙ open kit, ensure all equipment is ready, open and order sample tubes, draw up lidocaine for skin
☙ drape back once sterilization is complete
g. Landmark
☙ never trust tattoos, never trust skin-folds, (particularly in lateral patients)
☙ identify spinous process(es) below L1/L2 (level where conus medularis becomes cauda equina)
☙ consider ultrasound for patients with higher BMI / invisible / non-palpable surface anatomy.
☙ choose best space (non-rotated, non-scoliotic region), away from infx, ?neurotoxic tattoo ink.
h. Freeze skin thoroughly (but also really sound out initial track between spinous processes
☙ use a long skin needle (1.5 inch minimum w/ e.g.  lido 1% w/o epi x 5mL)
☙ freeze liberally but also sound with needle tip
☙ pain fibres are in skin but then only in paraspinal muscle (minimal pain in midline deep to skin)
☙ use patient's report of pain as a guide (e.g. pain on right, pull back and re-advance more to left)
☙ start ~0.5cm below the tip of the spinous process in midline
☙ keep needle midline (laterally / rotationally)
☙ when readjusting path, always return to skin (or within 2mm)
☙ "readjustments" when needle is significantly buried in tissue DO NOT CHANGE TRACK OF TIP
☙ only threaten to bend break needle
☙ goal is to bury 1.5 inch (3.8cm) "skin" needle on correct track toward CSF
☙ most adult CSF is ~5-6cm+, so no risk of reaching CSF with skin needle
☙ be conservative with very small child or ++cachectic pts, so as not to reach CSF with skin needle
☙ feel free to let go of needle / syringe while needle is buried (it will just stay there)
☙ physically move body & head to confirm needle angulation in body from multiple view points
☙ ensure needle-track rotation/angulation looks midline and approx ~ 30º cranial
i. Subarachnoid space puncture. After full frozen with optimal track sounded out:
☙ disconnect the lido syringe from the skin needle but leave needle in situ
☙ discard syringe / pick up spinal needle (± seeker/guide needle for e.g. 25g spinal needles)
☙ carefully remove skin needle and replace with spinal needle (± guide needle) in exact same track
☙ use same puncture hole.
☙ intention is to have bought you first 3.8cm of track towards CSF
☙ should be deep in midline (away from pain fibres) with only interspinous ligaments left

Note on Spinal Needles:
☙ atraumatic needles have the 'pencil point' tip with opening on the side (e.g. Whitaker®, Sprotte®)
☙ extremely low risk of post-dural puncture headache
☙ cutting needles have a sharp bevel (like a standard injection needle)
☙ low risk of post-dural puncture headache, but easier to get through a tough interspinous ligament
☙ start with atraumatic needle, but low threshold to change to cutting needle if struggling with ligaments.

☙ coach patient: tell them "pressure sensation" is normal but to say "ouch" (not jump) if there is pain
☙ also tell them sometimes one can get a strange pain in the bum or toes if needle brushes a nerve
☙ promise to stop if they say "ouch" but remind them not to move.
☙ if they say "ouch" then stop! Clarify if it is in right, left or middle?
☙ if unilateral pain: pinch needle @ skin, pull back to skin and reposition according to pain side
☙ whenever withdrawing a needle, pinch needle at skin to retain depth information
☙ use this info as a gauge, simplifying reinsertion process
☙ e.g. you know you can advance as far as the previous level without reaching CSF
☙ if midline or pressure, clarify that it is normal to have some pressure discomfort - ?re-advance

☙ When operator (you) encounter needle resistance: push a little harder!
☙ does it feel like pushing your needle against a concrete block (absolutely no give) - likely bone
☙ does it feel like pushing your needle into a firm block of wood (slightly spongey) - ?ligament
☙ if bone is suspected - pinch, back to skin, reposition, try again
☙ if ligament is suspected - persist and see if you can 'pop' through.
☙ If not, may need to upgrade to a cutting type needle (common in older patients)
☙ Once at a reasonable depth (e.g. 4cm in most adults) stop after every "pop" or every 3mm
☙ check for CSF by withdrawing stylet (wait a few seconds in case CSF flow is very low)

TIP: only withdraw stylet so tip stays inside the "hub" of spinal needle, to make stylet reinsertion easier.

☙ If making no progress after a few passes (ongoing pain, only bone without any sense of progress):
☙ consider moving up/down one spinous level and trying again (go to step g. above)
☙ this is a very valuable trick if scoliosis: try to pick segments with least amount of rotation
j. CSF is coming back: Hurray!
☙ obtain O.P. (if patient is lateral and info is actually relevant, otherwise don't waste time.)
☙ collect 4 sample tubes x 0.5-1mL of CSF each. Ideally 3-4mL in culture tube (e.g. #3)
☙ pass them off in order and ensure helper is appropriately labeling them in correct sequence
☙ smooth motion to remove needle(s)
☙ place bandaid

See LPs (Part 2) for CSF Orders and discussion of Testing Threshold of LPs (when to perform vs defer)

LEARNING OBJECTIVES:

Make the Most out of [Any] Simulation Training
☙ Barriers to learning with simulation:
☙ can feel self-conscious while participating / can feel like you're being judged.
☙ experience can feel contrived / artificial
☙ false emphasis on the importance of sim-participation (as compared to active observation)
☙ Majority of learning occurs during Debrief - not the simulation itself.

Suggestions for Success in Simulation Training:
☙ always be supportive and respectful of all participants.
☙ sim allows us to identify gaps and mistakes in a consequence-free environment
➔ so we do not make the same mistakes for real when someone's life is on the line
☙ pretend/act as if the scenario is real: talk to mannikin / pillow as if it is a person
☙ not the time to make jokes at the expense of the awkwardness of the situation
☙ other participants should get involved in authentic roles (and numbers) and also act as though the situation is real
☙ non "Hot-Seat" participants should actively observe, thinking through the process / decisions.
☙ e.g. as though they were in the hot seat (not observe passively) ➔ promotes maximal learning
☙ set aside adequate time for debrief (with focused learning objectives)
Optimize your personal performance and your team's performance in a Rural Resuscitation
☙ rural resus rarely has large team sizes like academic centres
☙ so need to make most of each team member present and their skill-set
☙ typically team = 1 MD, 2 RNs, lab/x-ray techs ± paramedics, extra RN, extra MD
☙ as Team Leader, you cannot afford to sit back and only boss others around.
☙ maximal efficiency comes from assigning each team member specific tasks that best match their skill set
☙ most resuscitations should start with the same foundational steps e.g.
a) IOM (IV, O2, Monitors)  or
b) MOVIE (Monitors, O2, Vital signs, IV, special Equipment)
☙ As physician, if not otherwise occupied, contribute with these chores! e.g.
☙ help put on monitors (don't forget to set NIBP to q 5 minute cycling)
☙ put on oxygen mask
➔ leave nurse or paramedic free to prioritize vascular access, for example.
☙ Same 'division of labour' concept applies to other times during resus where one team member is overtasked and others are idle:
☙ e.g. STEMI may require: ASA, NTG, fentanyl, heparin or TNK. RN could be left to do all, or:
☙ MD (or other free team member) can probably find and give oral ASA or sublingual NTG doses?
☙ leaves RN free to prioritize TNK mixing / administration ➔ shortens door to needle time.

➔ Don't bog down a team member with "mindless" tasks when someone else could manage a given simple task. Rather apply that team member's specialized abilities to tackle a more complex or higher priority item.

☙ As [physician] Team Leader, you must balance contributing to simple tasks with maintaining situational awareness.
☙ Any gains your team makes when the leader contributes with a simple task (e.g. applying a leg splint), will be more than lost if you as team leader fail to recognize a higher-priority issue due to the distraction (e.g. patient enters cardiac arrest).

➔ contribute by performing selective generic tasks, but do so cautiously and while maintaining situational awareness.
Checklists: the right ways and wrong ways to use them.
☙ A bad checklist is:
☙ poorly written / in paragraph form
☙ a step's meaning is unclear or difficult to decipher and requires concentration and excessive thought
☙ includes excess information (complicated charts or murky pictures) that are rarely required
☙ excess / non-applicable details should be eliminated altogether.
☙ rarely-needed details should only be in footnote-caveats or link to an external source.
☙ requires user to invest "significant thought", as compared to presenting a simple binary choice.
☙ A good checklist:
☙ set of quick, simple steps that can be easily processed while distracted by something more complex
☙ each step should be written in "point form" (e.g. these show notes?)
☙ in any case, a given step should be at most one clear, concise sentence.
☙ never "tells you what to do" but rather reminds you of correct order, and
☙ acts as a memory aid to confirm no critical step is missed
☙ should only address the first 5-15 [critical] minutes of a given resuscitation
☙ addresses immediate stabilization only. (Ongoing management should be in another resource.)
☙ Use your own checklist (yours or someone else's that you have vetted) - do NOT "look it up on the fly"
☙ Familiarity with "your own" checklist:
☙ allows you to review in advance for accuracy, applicability and clarity
☙ breeds confidence in how to manage the situation at hand.
☙ eliminates confusion in high-stakes situations and when time matters
☙ should be carried on your person at all times (flip book in your pocket/bag, on phone, etc)
☙ Institution-Provided checklists:
☙ may not be well written
☙ may not be readily accessible
☙ may not be up to date
➔ Create your own checklist(s) for common resus situations (e.g. anaphylaxis) or: thoughtfully select someone else's.
☙ Building your own checklists is time consuming but optimal:
☙ ensures the checklist is well optimized for your practice style and reality
☙ promotes familiarity with a resuscitative problem via the associated review and thought invested
☙ is easy to update if and when you choose to do so.
☙ Vetted, expert-written checklists are a great starting point though:
➔ RnR Rounds recommends & provides a copy of the Resuscitation Crisis Manual to every participant.
(Photo of RCM's Laryngospasm checklist is pictured above.)
The secret to a smooth Resuscitation:
1. Make sure you hit all applicable critical resuscitative steps
2. Divide and conquer by assigning the critical resuscitative tasks between team members in the most efficient manner possible.

LEARNING OBJECTIVES:

Recognize the importance of integrate ongoing resus Training & Practice into our careers.
☙ procedural competence is proportional to familiarity and regularity of rehearsal.
☙ To perform a procedure well, one needs to be practiced in advance.
☙ Good resuscitation requires occasional HALO Procedures (High-Acuity Low-Opportunity);
☙ "Just in time review" of HALOs is not possible due to the nature of resuscitation.
☙ thus, for HALOs (a critical procedure, not regularly practiced clinically), recurrent training is key.

➔ rural ER physicians really should prioritize ongoing regular rehearsal (in situ or in simulation) of HALOs (both procedures and critical patient presentations), in order to develop & maintain skills.
How to maintain Resuscitation Skills in isolation:
1. most important: set aside and protect a regular, recurrent time in your schedule each week / month.
2. practice by yourself (when no one else is available), but ideally practice with colleagues, and better: multidisciplinary colleagues (physicians, nurses, other paramedical professionals with an interest).

➔ RnR Rounds is award-winning, accredited, ongoing resuscitation & critical care training for physicians working in RURAL or ISOLATED communities. (Physicians can participate remotely online.)
How "fancy" does resuscitation training need to be, to be effective?
☙ it doesn't! Just closing your eyes and methodically thinking through a recent resus case or scary scenario is extremely effective if performed in an organized and thorough manner.
☙ however the more realism you add, the more effective it will become.

In increasing order of complexity / effort, here are various suggestions:
(a) on your own, write out line by line, step by step, (with flow charts where relevant):
☙ your actions when a patient presents with _________. (e.g. STEMI or upper GI bleed)
(b) with multidisciplinary colleagues [±🍻], sit around a table and perform (a) together as a team.
☙ assign roles realistic to everyone's training ± a 'facilitator' to keep the team on track.
☙ constructively and non-judgementally review team performance
☙ set a 2-3 learning objectives for future team sessions.
(c) take colleagues to an empty resus area and perform (b) together but physically moving in the space
☙ use hands on touching & rehearsal with tools (e.g. oxygen, monitor buttons, laryngoscope)
☙ balance facility budge issues with choice to open equipment
☙ even holding an item without breaking its packaging is helpful
☙ consider accumulating expired equipment which can be opened and handled in future
(d) low fidelity patient simulation - use a pillow or [non-sim] doll (etc) and treat it as a patient.
☙ actually lay out equipment (oxygen masks, defib pads etc) to go through the motions.
☙ talk to the prop as if it were a patient
☙ a team member can be the voice of the prop and introduce wrinkles (e.g. vomiting etc)
(e) medium to high fidelity simulation is both sexy and optimal but potentially expensive, and much more time consuming to utilize. (Anticipate 30-60 minutes of setup and take-down time for each session.)
➔ don't embark on hi-fi simulation lightly! It will frequently lead to facilitator exhaustion / burn out & collapse of a fledgling simulation program. Option (b) on a longterm recurrent basis is much better than 1 or 2 sessions of option (e) followed by program collapse.
That said...
☙ advantage of med-fi or hi-fi is the opportunity to practice "invasive" skills:
☙ e.g. defibrillate, bag-ventilate, intubate, insert chest tubes, deliver a baby etc.
☙ check with your health region as med-fi/hi-fi tools may be available to borrow in situ at your facility.
☙ some regional programs have funding to bring equipment & facilitation team to you.
☙ minimum headache - your team just shows up and learns!

➔ BOTTOM LINE: only bite off the appropriate level of complexity for your community.
➔ low-fidelity exercises on an ongoing monthly basis, are far more beneficial to your team than aspiring to top-shelf hi-fi exercises, but later giving up because it is too much work to get off the ground.
➔ START SMALL, START SLOW and only add sim complexity if there is time / energy to do so.
Ideal frequency of rehearsal / simulation:
➔ ANY rehearsal and ongoing practice is better than NONE!
☙ multiple studies have been conducted, usually examining frequency of CPR retraining.
☙ results are all over the map but extrapolating:
☙ 6 weeks (post course) participants forget approx 50%
☙ 6 months (post course) forget 75% or more

☙ Monthly team-simulation activities may be the sweet spot(?), balancing:
☙ cognitive atrophy of resuscitation skills and procedures, with
☙ a realistic schedule for team member's personal lives

References:
1. Optimal training frequency for acquisition and retention of high-quality CPR skills: A randomized trial Robert Anderson 1, Alexandre Sebaldt 2, Yiqun Lin 3, Adam Cheng 4
2. Retention of cardiopulmonary resuscitation skills in medical students utilizing a high-fidelity patient simulator.

LEARNING OBJECTIVES:

Review of Acid/Base Metabolism
☙ see emcrit.org episode #44 for an alternate/novel approach to acid base
☙ unless you are worried about oxygenation specifically, VBG (venous blood gas) are safer and easier for repeated acid/base assessments.
Conventional review of acid/base as follows:
☙ 2 extracellular buffer systems:
(1) bicarbonate is both a buffer and highly modifiable pool for creation/elimination of acid.
(2) protein system (e.g. predominantly albumin) more of a pure buffer (not creation/elimination)
☙ third intracellular buffer system: phosphate system
☙ bicarb is the main system for acid-base management and definitive compensation
☙ bicarb exists in balance between two forms. (see formula in album art above)
☙ 2 systems: lungs & kidneys can balance bicarb, CO2, water to create / destroy [acid + bicarb]
I. Respiratory System can be part of the problem or part of the solution to acid-base disorders
☙ hypoventilation => CO2 retention => increases acid load.
☙ if helpful (is fixing pH) = respiratory compensation, (e.g. hypoventilation in bicarb overdose)
☙ but if pathologic = respiratory acidosis (e.g. hypoventilation in opiate overdose)
☙ hyperventilation => CO2 elimination => removal of acid respiratory alkalosis
☙ if helpful (fixing pH) = respiratory compensation, (e.g. hyperventilation while running 5 km)
☙ but if pathologic: respiratory alkalosis (e.g. anxiety/panic induced hyperventilation)
☙ respiratory system can react and begin to change pH almost instantaneously (seconds to minutes)
II. Metabolic System (kidneys largely) - much slower system (hours to days)
☙ insight into duration of acid/base process.
How to analyze a blood gas:
1. determine is 1º problem acidosis or alkalosis? (i.e. pH < 7.35 or >7.45)
2. are respiratory and metabolic systems contributing to the problem or mitigating the problem?
☙ pCO2 => respiratory problem or compensation (or no change / no compensation)
☙ HCO3- => metabolic problem or compensation (or no change / no compensation)
☙ if both respiratory & metabolic systems are part of the problem then it is a mixed acidosis (or alkalosis)
What is the effect of NaHCO3 on the body?
1. Na+ => hypernatremia
2. HCO3- => metabolic alkalosis
☙ healthy brain/body will try to compensate:
☙ respiratory compensation will try to add acid (counter met.alk.) => hypoventilation / ↑CO2
☙ intracellular buffering (H+ out of cells / K+ into cells) => (extracellular) hypokalemia
☙ total body potassium is conserved, but higher proportion extracellular => relative hypokalemia
☙ regardless of total body K+, this extracellular hypokalemia is still dangerous <= replace now!
☙ potassium replacement => total body hyperkalemia (extracellular normalization)
☙ eventual hyperkalemia and need for potassium removal (long term)
Management of acute severe Hypernatremia, Hypokalemia
Hypernatremia: (if severe: seizures, coma death)
☙ gentle correction when patient is stable (target ~0.5mEq/hr)
☙ too aggressive a correction can cause cerebral edema
☙ when patient is unstable (already has cerebral edema from excessively rapid hypernatremia):
☙ bolus of free water (e.g. D5W) may be necessary and life saving.
Hypokalemia:
☙ potassium replacement: far more efficient when given orally (vs IV)
☙ with relatively normal renal function, can give up to potassium 160mEq PO per 24hrs (80 bid)
☙ be sure to recheck potassium after this before giving more.
☙ potassium is mostly intracellular
☙ when extracellular potassium is low 1 mEq, total body potassium is low 100-200 mEq
☙ hence for each mEq of replacement desired (e.g. 2.5 -> 3.5) requires 100-200 mEq(!)
☙ Magnesium is required in potassium metabolism.
☙ check the Mg++ level or give a conservative dose of MgSO4 2g IV to cover the bases.

=> KCl 10mEq IV is potentially toxic to veins, and is a drop in the bucket if you really want to correct K+
=> USE ORAL POTASSIUM REPLACEMENT, not IV when patients are able to tolerate oral replacement.

LEARNING OBJECTIVES:

How (When) to Troubleshoot a Difficult Airway
=> During SETUP, in ADVANCE of pushing drugs!!
How to approach an intubation in a rural hospital
Pre 1) Examine the Patient (LEMON mnemonic)
☙ Look
☙ Evaluate (3-3-2 Rule)
3 patient fingers in patient's mouth (vertical: upper <-> lower incisors)
3 fingers (yours) measuring hyo-mental distance (horizontal: neck (hyoid) <-> chin distance)
2 fingers (yours) hyo-thyroid distance (vertical: thyroid cartilage <-> hyoid bone)
☙ Mallampati (how much of the uvula is visualized?) Grade 1 (best)-4 (scary)
☙ Obesity, Obstructions, Obstetrics (pregnant mom) - each of these are read flags for diff airway.
☙ Neck extension (evaluate capacity for extreme neck extension)
Pre 2) Setup "Room" / Environment Setup (ABCDE)
☙ Aspiration (manage it) => Suction set up and ready!
☙ Bag Valve Mask (BVM)
☙ Circuit (ventilator is primed / ready to connect or someone is assigned to manage BVM after)
☙ Drugs (post intubation maintenance) e.g.
i) morphine 100mg + midazolam 100mg into 100mL NS minibag
☙ start new morphine 1mg/mL + midaz 1mg/mL solution @ 5mL/hr & titrate
ii) fentanyl + propofol (combined or separate infusions)
iii) ketamine (infusion or periodic boluses)
=> choose (when able), based on regional transport team preference / protocols!
☙ Extra / Emergency O2 supply (what is your move if your 1º supply fails or is exhausted)
Pre 3) Setup Airway Equipment (ABCDE) for "Plan A" (e.g. direct look intubation)
☙ Aspirate Air (in the ETT balloon) => Syringe
☙ Blades & laryngoscope handles
☙ [C-shaped] oral airways
☙ [Duct-] tape (system to secure ETT once it is in position)
☙ Endotracheal Tubes (selection of sizes)
Pre 4) Define & Setup all extra equipment needed for:
☙ Plan B - e.g. Video-laryngoscope (for if Plan A fails)
☙ video scope in sight, plugged in, turned on to test, extra tube with video-stylet
☙ Plan C - e.g. supra-glottic device (e.g. LMA, King Tube, etc)
☙ correct size(s) out, ready to grab if needed
☙ Plan D - e.g. emergency cricothyrotomy (Scalpel-Finger-Bougie technique)
☙ eye protection on, scalpel (e.g. #10 blade), bougie, #5.0 ETT in easy reach
☙ Adjuncts: e.g. bougie, stylet
Pre 5) Induction Medication Setup: (setup up last to force thorough set up of all other equipment
☙ Induction drug choice is a complex topic because no optimal "One-Size-Fits-All" (OSFA) cocktail exists for every patient and every situation.
☙ Rural drug choices are limited...
☙ A reasonable "OSFA" option (works okay in almost all situations of ~normotensive patients:
1. ketamine 1.5mg/kg - anticipate secretions / need for early suction
2. succinylcholine 1.5mg/kg
☙ plan to push back to back

Now room is ready for a patient (- everything up to this point can be done prior to a patient arriving!)
Pre 6) With patient in room:
☙ patient on bed
☙ confirm/obtain quality IV(s)
☙ monitors are on an cycling (NIBP q5 mins, SpO2, EKG, End-Tidal CO2 is ready to be setup)
Pre 7) Correct Positioning:
☙ boosts successful intubation to the same degree as using a video-laryngoscope!
☙ take your time and position the patient correctly:
1. use a ramp pillow (or make one out of blankets)
2. target ear lobes at the same altitude as the sternal angle
3. neck is in mild extension so face is parallel to ceiling
4. bed to correct height for you to work, moved away from wall (etc) to provide adequate room
Pre 8) Pre-oxygenate with either:
☙ 3 minutes w/ high-flow nasal cannula (NC) + Non-Rebreather mask
☙ 3 vital capacity breaths.
Pre 9) PPE appropriate to situation:
☙ wear face shield or safety goggles (in case you get to Plan D)
Pre 10) Survey room set up, review order of Plans A-D with team and each person's role

Push Drugs)
☙ back to back as quickly as physically possible.
☙ note position of second hand on the clock
☙ continue high flow NC for value of apenic oxygenation
☙ after 60 seconds:

Plan A) either: success! (pass the tube) or trouble! (ask yourself what is the limitation?)
☙ common limitations can include:
☙ I can't see through this fluid -> suction
☙ I can't see get the full view I need -> Plan B (etc)
☙ I can see the cords but can't get the tube to the target -> adjunct (e.g. bougie?), smaller tube etc.
=> Repeat until some device has been placed in the airway
☙ if it's an ETT fight the urge to stuff the tube into the right mainstem bronchus (RMB)!
☙ visualize the tip of the ETT and deliberately place at correct depth
☙ announce depth marking at teeth to the team (to detect future unintentional migration)

Post 1) Splint, Attach, Verify
☙ assistant MUST anchor palm against patient's face & pinch tube @ lips. (stop migration)
☙ Attach the BVM ± ETCO2 detector
☙ Verify: (CO2 detection is LAST!)
1. observe tube (should mist aggressively on every exhalation
2. listen and observe to both lung fields (rule out RMB intubation)
3. finally, check to see if ETCO2 supports or contradicts your other findings
☙ CO2 monitors are slow to react (up to 15 second delay)
☙ CO2 monitors like to recalibrate at the worst possible moment
☙ CO2 monitors sometimes lie
☙ colour-changing lose their abilities over time
☙ both can detect CO2 early on from the stomach in an esophageal intubation...
☙ CO2 monitors are NOT the absolute truth!
☙ Use them like a second opinion to consider not override your assessment and judgement.

Post 2) Secure the patient:
☙ secure (tape?) the tube definitively.
☙ activate your ventilator / dedicated BVM operator plan
☙ activate your post-intubation sedation strategy

Post 3)
☙ celebrate!
☙ review & critique so you can be better next time (we can all, always be better next time!)
☙ help others!
☙ share your case stories by recording a podcast ...or tell "another podcaster" so they can share it!
Download (pdf): RnR Rounds Airway Checklist

LEARNING OBJECTIVES:

What are you priorities in addressing a potentially violent situation?
☙ When it comes to safety, your priorities must be:
1. first and foremost yourself
2. your partner (or team)
3. third and finally if time permits: the patient
☙ you are no use to your team if you are injured.
☙ an injured care-worker becomes a liability to their team and will reduce time and energy that could otherwise have been spent on the patient.
How do you safely approach a potentially violent patient and what is the end goal?
☙ answer depends on where you are / where the patient needs to be.
☙ typical rural hospital (without psychiatric holding): patient must be shipped.
☙ by ground vs by air? (Will affect how deeply sedated the end target is - see below.)
A reasonable approach:
1. assemble as large a team as you can: (doctors, nurses, paramedics, security, janitorial staff, etc)
2. assign each team member a specific role:
☙ ideally one person for each limb
☙ one person for the head to apply oxygen mask (airway support and spitting / biting protection)
☙ one person with pre-drawn IM syringe to be given (through clothing if necessary)
3. approach and restrain patient as a team and administer medication:
☙ physically restrain patient in whatever position is easiest / safest for the team, however:
☙ ensure patient is breathing well.
☙ Cases of ASPHYXIATION have been reported, usually when the patient is restrained in prone position.
☙ IM injection into a large muscle group (e.g. shoulder, thigh or buttock.)
4. continue manual restraint until drugs take effect (ensuring unrestricted breathing), then slowly release,
☙ replace team members with physical restraints if indicated.
Air Transportation Considerations:
☙ world experts in aeromedical transport strongly encourage intubation ± paralysis for potentially violent patients being transported by air(!!)
☙ there are many reasons making air transport of a violent patient much more complicated and dangerous than road transport.
☙ A "break away" violent patient in an airplane is potentially catastrophically fatal
☙ thus the room for error in air-transport of violent patients is razor thing.
☙ be aggressive and preemptively intubate ± paralyze patients in order to protect them.
What are some good pharmacological cocktails and approaches?
First Choice: droperidol 5-10mg IM
☙ great single agent choice, quicker and more predictable in onset and dosing.
☙ best first line choice (if you can get it.)

Second Choice: olanzepine 5-10mg IM
☙ great single agent choice, quicker and more predictable in onset and dosing.
☙ great alternate to droperidol (if you can get it.)

Benzodiazepine Adjunct: midazolam 1-2mgIM
☙ midazolam IM has more optimal/predictable pharmacokinetics than IM lorazepam
☙ midazolam can be added to the above cocktails if benzo is desired:
☙ amphetamine intoxication
☙ seizure activity / risk
☙ be prepared to support the airway (oxygen, jaw thrust, rolling patient)
☙ while midazolam 2mg is generally well tolerated it may lead to:
☙ relaxation & closure of the airway requiring repositioning
☙ hypoventilation requiring O2 support
☙ if combining midazolam to the above "single-agent" options, reduce dose of droperidol or olanzepine.

Final "Old School" Choice: "B52"
☙ Benadryl® 50m[optional], haloperidol 5mg + lorazepam 2mg - all given IM in one syringe
☙ great acronym but the antihistamine diphenhydramine (Benadryl®) is rarely needed
☙ can certainly be delayed and considered depending on initial response (EPS Sx?)
☙ EPS (extrapyramidal side effects) from older antipsychotics like haloperidol. Include:
☙ restlessness
☙ muscle contractures
☙ tremors
☙ haloperidol 5mg + lorazepam 2mg (IM) is:
☙ well supported in psychiatry literature
☙ but slower and less predictable in onset (may take up to 15 minutes per aliquot = NOT fast!)
☙ yet ubiquitously available in rural communities(?)
☙ great choice in rural communities when more modern IM drug choices (above) are not available.

Big Guns: ketamine 5mg/kg IM
e.g. imminent danger or this patient needs to be flown
☙ will work within 3 - 5 minutes
☙ requires a larger volume IM dose (e.g. ±10 millilitres)
☙ note: literatures shows it is safe to give up to 20 mL IM in a single dose/site (!!)
☙ do NOT give divided doses, give one [large] single syringe/single stick dose.
☙ apnea is possible but unlikely.
☙ have stretcher, SpO2 monitor, oxygen mass within easy reach to be safe.
☙ if progressing to intubation, you now have lots of time (30+ minutes) to set up, top up and definitively secure the patient.
References / Post-Recording Evidence:
☙ For more FOAM on pharmacological sedation check out emcrit.org/279
☙ A Prospective Study of Intramuscular Droperidol or Olanzapine for Acute Agitation in the Emergency Department: A Natural Experiment Owing to Drug Shortages. Ann Emerg Med. 2021 Aug;78(2):274-286. doi: 10.1016/j.annemergmed.2021.01.005. Epub 2021 Apr 9.
⇒olanzepine ~10mg IM vs droperidol 5mg IM were found to have equivalent time of onset
☙ (16 vs 17.5mins)
⇒olanzapine group was more likely to receive additional medications for sedation
⇒droperidol group had slightly higher EPS, but NO increased need for EPS treatment

LEARNING OBJECTIVES:

"HALO" Procedures (High Acuity, Low Opportunity)
☙ greatest challenge is psychological. Specifically: self-doubt or procrastination
☙ we generally know what intervention is indicated / what needs to be done
☙ however we're lacking confidence, so we're tempted to look for moral support or "an out"
☙ e.g. call a specialist to "review" (or just reassure, if we already know what they'll say)
☙ unnecessary delays in "HALO" situations lead to higher risk of complications while waiting, or deterioration of conditions for performing the intervention
☙ e.g. progressively swelling airway needs intubation. (Nothing good comes from delaying.)
☙ "I've never done this before" is not an excuse to delay if you know what needs to done.
☙ e.g. choking on a foreign body and inability to clear it with abdominal thrusts needs a crich.
☙ Ongoing practice and psychological exposure helps with mental preparation:
☙ if you listen to this episode and need to do a suprapubic tomorrow you will feel more confident
☙ if you regularly discuss "what if" HALO situations with colleagues you will be better prepared.

Routine review ("rounds") with colleagues about hypothetical "HALO" circumstances and resuscitation topics leads to enhanced preparation. You will be more mentally prepared.

☙ Ongoing learning and encouragement from peers translates to being more comfortable and more prepared for HALO circumstances.
☙ Regular rehearsal (even if just verbal and in your mind), will help you retain HALO skills.
Ultrasound Guided Procedures in Rural Practice
☙ procedures are almost always made easier by ultrasound
☙ Need 2 things for U/S Guided procedures:
1. need a fundamental understanding of how needle guidance works under ultrasound
2. need a fundamental understanding of anatomy & physiology (i.e. from medical school)
☙ Better confidence, informed guidance, lower rates of complication and "collateral damage"
☙ It is definitely worth investing and developing your ultrasound skills
☙ make the time and invest in this revolutionary skill!

Long Axis Vs Short Axis guidance:
☙ Long Axis: ultrasound plane is kept in line with long axis of the needle
☙ you see most of the shaft of the needle from tip to where it exits the beam.
☙ think of laying a needle on top of a piece of paper (2D ultrasound beam)
☙ Short Axis: needle pierces
☙ you see only one point on the screen -- may be the tip or several cm proximal.
☙ think of poking a needle through a piece of paper (2D ultrasound beam)
☙ Advantages / Disadvantages:
☙ in long axis you see the full length of the needle and know where the tip is at all times
☙ long axis is a little more technically challenging to master (a little more practice is required)
☙ depending on location, skin real estate may be limited
☙ e.g. curvature of finger limits probe positioning in long. (May not work for therapeutic goal)
☙ short axis requires smaller foot print and requires little to no skill to use
☙ in short axis, tip could be much deeper than where dot (of shaft) is visualized.
☙ to use short axis safely, "inch worm" technique is required to maintain tip localization:
☙ Slide beam 3mm ahead of needle tip, then advance tip until it appears. Repeat.
☙ In practice: switching probe between long & short axis will provide maximum information.
An Approach to [temporary, emergency] Suprapubic Catheter
1. Use Ultrasound and examine anatomy. Location of the most superficial aspect of bladder wall may surprise you.
2. Equipment Gathering:
a. biggest, longest, IV catheter (without one-way valve) e.g. 14g, ideally 8+cm long
b. simple IV drip set without a back-flow valve e.g. secondary drip set; cut off the drip chamber
c. bucket
d. sterile procedure stuff: e.g. gloves, chlorhexadine + gauze, sterile probe cover if using U/S
e. local anesthetic e.g. lidocaine 1% w/ epinephrine
3. Do the Procedure:
a. sterilize
b. freeze skin
c. place catheter into giant bladder at most superficial location & remove sharp
d. connect soft catheter into drip set
e. let physics do its thing.

LEARNING OBJECTIVES:

How to approach Disproportionate Pain (pain disproportionate to exam findings)
☙ Always consider Disproportionate Pain as a red flag.
☙ satisfactorily rule out serious occult conditions prior to discharge
☙ depending on location consider:
☙ intracranial hemorrhage
☙ aortic dissection / aneurysm
☙ pneumothorax
☙ ischemic bowel
☙ cauda equina syndrome
☙ compartment syndrome
☙ necrotizing fasciitis
☙ For every patient visit ask yourself: What occult condition could I be missing, that might kill this patient?
☙ always treat Disproportionate Pain as a red flag for occult, potentially deadly conditions!
Approach to Refractory Pain
☙ You can think of pain as a combination of 3 subtypes: (tissue/organic type pain, neuropraxic pain, emotional contribution) see Episode 004 for more details.
☙ each type requires its own targeted treatment approach.
☙ Jonathan's approach to Tissue-Type Pain refractory to typical ED treatments:
1. look for scary causes (see Disproportionate Pain section above)
2. consider the role / contributions of neuropraxic or emotional/stress pain types.
3. for residual tissue type pain, consider why the patient is not responding to usual (or generous) standard treatments of anti-inflammatories or opiates etc.
☙ consider innate pharmacologic non-responders
☙ e.g. 10% of caucasians are unable to metabolize codeine to it's active-morphine metabolite
☙ consider tolerance, especially from chronic users of:
☙ alcohol
☙ opiates (or antagonists)
☙ especially marijuana
☙ chronic THC or CBD use at approx 0.5g per day seems to routinely lead to:
☙ profound opiate resistance
☙ altered pain sensation, tolerance to pain
☙ anecdotally: pre-operatively I recommend stopping marijuana usage at least 4 weeks ahead
4. consult anesthesiology for suggestions if/when possible!
5. if approaching refractory pain on your own consider:
i. if admission for pain control is possible/appropriate.
☙ Many advanced interventions will require supervision.
ii. if local anesthetic (LA) injection (e.g. bupivacaine) is an option.
☙ often will provide significant relief, albeit only for a few hours.
☙ consider adding dexamethasone 4mg or use LA+epi for more prolonged duration.
iii. analgesic-dosed ketamine infusion or intermitted boluses
☙ see Episode 003 for more on analgesic ketamine dosing
☙ requires admission for re-dosing / constant monitoring
☙ avoid prescribing oral ketamine for home use.
iv. lidocaine IV infusion
☙ requires admission for re-dosing / constant monitoring
v. gabapentin PO
☙ subacute (non-instantaneous) solution which can be started or titrated from the ED.
☙ more effective for neuropraxic pain.
5. focus on "foundational aspects" of pain control
☙ the sum of all little contributions (e.g. acetaminophen(etc) + exercise + PT) will be part of the best and final solution
☙ reframing / recalibration of patient expectations may be needed?
☙ positioning, splints, resting the body part (for tissue-type pain)?
☙ heat / cold?
☙ optimization of Tier 1 medications? (see Episode 004)
☙ consideration of gabapentin or a steroid injection?
Ultrasound assessment for vascular flow
☙ which probe to use?
☙ consider shape of probe based on surface anatomy / vascular target location.
☙ e.g. large curvilinear probe will be not make great contact with the foot.
☙ consider higher frequency probe for superficial target (e.g. < 6cm), for optimal resolution
☙ KNOBOLOGY - look for frequency selection and adjust for optimal resolution
☙ some manufacturers let you choose in MHz,
☙ others use subjective labels such as: RES[olution], GEN[eral], PEN[etration]
☙ know your machine!
☙ Colour Mode Doppler (a.k.a. "Color", "Colour Flow", "C", etc)
☙ machine can determine if echos inside the sample box are moving towards or away from probe
☙ classically: moving towards probe = painted red; away = painted blue
☙ some machines allow for the colour assignment to be changed
☙ so check "colour graph" on the screen to confirm if direction matters
☙ shade of red/blue is proportional to the velocity towards/away.
☙ e.g. lighter red = faster than darker red.
☙ Movement of tissue MUST BE (at least partly) in the plane of the sound waves.
☙ if flow is absolutely perpendicular to sound waves, no velocity is detected so no colour is painted.
☙ angle your probe so sound waves are as parallel as possible to direction of flow
☙ e.g. in arm, lay probe more "flatly" (while maintaining contact), aiming beam towards elbow.

LEARNING OBJECTIVES:

Cardiac Arrest? You must be Aggressive and Quick!
☙ do whatever you can to get more help (physicians, nurses, paramedics etc.)
☙ ideally have someone (2nd MD?) dedicated to assessment / management of "Hs & Ts"
☙ "Hs & Ts" = Hard to Think?   (Difficult Mnemonic!)
☙ Try: MECHS DEATH: (better mnemonic(?) for REVERSIBLE causes of Arrest)
  ☙ MECHS (physical problems)
☙ MI
☙ Embolism (pulmonary)
☙ Cardiac tamponade
☙ Hemo/Pneuothorax
☙ Shock (hypovolemia)
☙ DEATH (OG) (metabolic problems)
☙ Drugs
☙ Electrolytes (K)
☙ Acidosis
☙ Temperature (hypothermia)
☙ Hypoxemia
☙ even better than a mnemonic?
➔ Read the list off a poster on the wall, or a reference chart!
POCUS in Cardiac Arrest
☙ Point of Care Ultrasound in cardiac arrest, saves lives.
☙ several great (validated) protocols to choose from:
1. EGLS (Echo Guided Life Support) - protocol & course
☙ great one-day in-person course, or an online option.
2. E-FAST (Extended FAST Exam)
3. RUSH Exam (Rapid Ultrasound in Shock and Hypotension)
☙ POCUS can contribute to ruling in/excluding all 5 "MECHS" causes above!
Procedures in Arrest (e.g. pericardial tamponade drainage)
☙ Ultrasound makes procedures easy!
☙ either needle guided (needle visualized in real time) or
☙ "needle targeted" (visualize the location of the target then but then proceed blind)
☙ still better than "old-school blind"!
☙ Pericardiocentesis thoughts:
☙ heart is an anterior organ, so from subxiphoid location, keep needle angled shallow / anterior
☙ Especially in a Cardiac Arrest, be BOLD!
☙ if a ["scary"] procedure is indicated: Do it. Do it quickly and with confidence.
☙ Remember: a patient in arrest is dead and they're not going to get more dead. If the indicated procedure is going to save them, it needs to be done aggressively and quickly.

LEARNING OBJECTIVES:

Pain Assessment & Control in the ED
☙ ED physicians are RARELY aggressive enough in adequately addressing symptom control (particularly pain control)
Categories of Pain:
(A) "Tissue-Based Pain"
☙ mechanism: muscular / mechanical / prostaglandin mediated
☙ e.g. tension headaches, soft tissue injuries, fractures, acute inflammation (e.g. appendicitis), etc
(B) "Neuropraxic Pain"
☙ mechanism: inflammation, compression or trauma to a nerve causing perceived pain in the tissues
☙ dermatomal pattern, generally burning in nature and refractory to anti-inflammatories or opiates.
☙ frequently associated with dysesthesia
☙ e.g. normal stimulus such as blanket or clothing on skin is intolerable.
(C) "Emotional Pain"
☙ related to stress / anxiety
☙ arise from acute trauma (fall, MVA), stress at home or work
☙ contributes to, or causes perception of pain

Jonathan's Approach to Acute Pain Control:
(1) ASAP (as soon as patient arrives in pain, moaning etc) determine if there *may* be a tissue component and address this with Tier 1.

Tier 1:
give (or top up if patient has already taken):
(a) acetaminophen 1g PO qid [key contraindication = liver failure]
(b) plus NSAID [key contraindication = renal injury/failure, peptic ulcer disease]
☙ e.g. ibuprofen 400mg PO qid
☙ maximum efficacy reached at 400mg dose (and same efficacy as all other NSAIDs!)
☙ lowest risk of all five NSAIDs in terms of GI Bleed risk.
☙ e.g. ketorolac 10mg IM/IV
☙ use if an anxiety component or skepticism of ibuprofen, for placebo benefit of injection

(2) go do stuff for at least 30 mins.
(3) now properly assess patient, actively assess pain looking for one of 3 responses:
(i) "Wow I feel a lot better" or "my pain is almost gone."
-> Do the doctory stuff
-> Send them home with a hand written note for how to take OTC meds appropriately.
(ii) "Not sure, not really" or "no."
☙ red flag for possible chronic pain (± acute flare)
-> Focused evaluation for contribution of pain types (A)(B)(C) above
(a) if still significant Tissue-Based Pain -> order Tier 2 now.
☙ builds trust / relationship
☙ look harder for more serious pathology (occult #, nec fasc, etc.)
(b) if significant Neuropraxic Pain component
-> do the doctory stuff but counsel re need for long term approach.
-> counsel patient / prep them on need for long term MD (family doc) support
-> consider gabapentin or other therapies (see future episodes) but not essential in ED.
(c) if significant Emotional Type Pain (or chronic pain factors):
-> grab a chair and spend 10 minutes assessing / counselling
-> solution is going to rest in:
☙ targeting the real problem / root cause (e.g. divorce proceedings causing neck pain)
☙ team-based / multimodal approach:
☙ life-style changes & appropriate expectations
☙ e.g. improve quality of life & function not perseverate on pain-free (if unrealistic)
☙ see GP for SSRI if indicated? (not benzos or opiates!)
☙ see a real counsellor (not a friend or relative)
-> consider optimizing non-addicitive / non-street value meds if appropriate
☙ but not if patient is going doctor to doctor and failing to pursue a family doctor.
Often greatest contribution ER physician can make is helping patient understand:
☙ generally there is no quick fix
☙ team required, especially a constant physician (GP) who will track and direct
☙ solution lies in realistic expectations, lifestyle changes, and not a "magic pill"
(iii) "only oxycontin works" or "I didn't take your useless drugs"
-> don't be judgemental or condescending! Seek to understand why the patient has refused:
☙ address patient education issues (yes, acetaminophen is okay despite your kidney problems.)
☙ educate them when/when not appropriate
☙ educate them re opiate prescribing safety and need for one central physician & contract.

Jonathan's Emergency Department Opiate Refill Philosophy:
☙ if > 6 tabs of opiate are requested: patient is in the wrong place.
☙ Need to see GP or surgeon etc or whichever singular doctor is contracting with them for opiates.
☙ A responsibility/requirement of being a chronic opiate consumer, is to be able to preplan for refills well in advance of running out.
☙ If their opiates are stollen, the situation still doesn't change. This should serve as a wake up call as to how dangerous these meds are, and the need for the patient to come up with a better solution for security of their drugs, or just get off them.
☙ Refills of chronic opiates from the ED in a short interview is inappropriate and dangerous. You don't know their past. Do they have an opiate contract? Are you shooting an addictions colleague in the foot by giving the patient more? Does this person freely share their opiates with friends and relatives who ask? Do they sell their meds at $60 per pill? Of course we want toe like to think no, but there is no way for us to know and a symptom of addiction is poor insight and judgement.
If you are going to refill chronic opiates anyway:
1. check the chart(s) as much as you are able to ensure this is not a regular pattern.
2. be sure to attempt to call the primary prescribing physician to discuss and obtain their blessing
3. DICTATE a letter describing the visit, your rationale and decision and send to the primary prescriber
☙ if you can't be bothered to do all three things then don't refill the prescription! Don't meddle in an iatrogenic disease with so much potential to cause misery and suffering!

Tier 2: (useful in Tissue-Type Pain but generally unhelpful in Neuropraxic/Emotional-Stress Pain)
-> hydromorphone 1-2 mg PO q1hr prn [onset ~ 30mins, duration ~ 2-3hr]
☙ HM is synthetic -> does not cause histaminergic side effects (nausea, pruritus)
☙ unlike morphine, no need to give anti-nauseant
☙ unlike codeine, efficacy is reliable and predictable
☙ unlike e.g. Tramacet (mixed drugs), give separately so components can be titrated / maximized
☙ if patient is nauseated/vomiting (don't want to give PO)
-> treat nausea first e.g.: ondansetron 4mg IM/IV
☙ consider whether vomiting might be source of pain.
☙ consider waiting 30 mins to assess (then oral analgesia if needed vs IV now)
☙ if patient is in extreme pain (don't want to wait 30 minutes for relief)
-> fentanyl 25-50mcg IV q 5mins prn [onset ~2-3 mins, duration 45 mins]
☙ fentanyl is also synthetic (see above)
☙ give loading dose of oral hydromorphone dose (above) at the same time.
☙ as fentanyl wears off, HM will be peaking thus providing longer lasting analgesia.
☙ if refractory to opiates (no real response after HM 4mg PO or HM 1mg IV or fentanyl 150mcg)
☙ confirm you treating tissue-type pain (neuropraxic / emotional type pain is often refractory)
☙ consider refractory/disproportionate pain as a Red Flag (see next episode)
☙ consider adding in low dose ketamine [Episode 3] or lidocaine as an adjunct.

(4) Approach to Pain in Specific-Diagnoses: (other serious pathology managed/excluded)
☙ significant anxiety component -> lorazepam 1-2mg PO/SL/IV as a trial, then assess and treat
☙ dental pain -> anti-inflammatories + antibiotics, coach them as to what to expect over next 48hr
☙ headaches -> use migraine protocol (non opiate), or IV fluid + anti-inflammatories
☙ If refractory and giving opiates, you should be considering whether a Head CT is indicated
☙ abdominal cramps -> try hyoscine 10-20mg PO/IV or 5-10mg IV (diagnostic value too!)
☙ biliary colic, pancreatic pain -> diet restriction and maybe admission (not opiates at home)
☙ renal colic -> send home with a 6-pack of HM, but if not settling likely need imaging ± admission
☙ MSk -> never requires opiates (home on Tier 1 type meds)
☙ Flail Chest -> need to be admitted for epidural or regional anesthetic infusions.

Who should get opiates?
1. chronic cancer-based pain and other end-of-life chronic pain patients.
2. patients intra-operatively and acutely painful traumatic or other resuscitative situations
3. patients post-operatively for up to 72 hours afterwards then a rapid weaning and transition.

Scary Opiate Stats:
☙ 4.7 people die every day in BC as a result of opiate abuse(!!)
☙ (0 people die every day as a result of chronic pain!)

What we should be doing rather than prescribing opiates:
☙ Sit with your patient and be empathetic. Listen. Be kind.
☙ Educate them that pain is a normal and healthy part of life.
☙ Pain should lead us to modify our lifestyle and habits including expectations of what we can do.

Opiates in Resuscitation:
☙ be liberal / aggressive (see Tier 2) in managing acutely painful resuscitative situations:
☙ trauma
☙ CV disease
☙ peritonitis / colic
☙ fractures
☙ etc

Be aware of ALTO (Alternative to Opiates) as a source of a great many alternative pain-control options.
Take Home Points:
1. Be aggressive in addressing patients' pain, try to catch them as close to triage as possible!

2. Max out Tier 1 meds as much as medical history will allow.
☙ Always combine acetaminophen and NSAID when both are safe to give
☙ use max doses for efficacy (not max doses of safety) e.g. ibuprofen 400mg max

3. Opiates are necessary evils in some cases (severe, acute tissue-based pain)
☙ for other cases (e.g. 2 weeks of back pain or 2 weeks of shoulder pain that isn't going away), we should be spending MUCH more time in our shift educating patients about why opiates are a bad idea, and are more likely to shorten life than improve long term quality.
☙ Chronic opiates should always be prescribed through a stable clinic arrangement, including an opiate contract with one central physician who can offer follow up.

LEARNING OBJECTIVES:

Acutely Ischemic Limb Injury (Trauma)
(a) arterial ischemia (arterial issue -> pale, cool limb, often disproportionate pain)
☙ viability = 6-12 hours
☙ goal is to "gently" realign a limb into more-normal anatomic alignment in hopes of restoring vascular flow.
(b) Compartment Syndrome (venous obstruction -> ↑compartment pressures, disproportionate pain)
☙ viability < 4-8 hours
☙ surgical fasciotomy requires
☙ 6P's of Compartment Syndrome: Pain (esp. on passive stretch), Pallor, Perishingly cold, pulselessness, paralysis, parasthesias
☙ compartment pressure measurement NOT mandatory, you can diagnoses clinically with 6P's
Approach to Crash Sedation
☙ Queen's Procedural Sedation Cocktail: (use this for any/every sedation)
☙ ketamine 0.3mg/kg IV push (1 dose only)
☙ propofol 0.4mg/kg IV push (1 dose only)
☙ propofol 0.1mg/kg (~1mL) IV aliquots to titrate
☙ Room / Equipment Setup:
☙ IV
☙ O2 (ETCO2+O2 combined device best)
☙ if ETCO2 not available use simple face mask @ 6 Lpm and observe plastic for misting on exhale)
☙ monitors [SpO2, NIBP (q 5min), EKG, see notes re ETCO2]
☙ verbal consent (unless patient isn't under duress from pain or previous analgesics)
☙ airway rescue equipment [BVM, oral-pharyngeal airway selection, intubation kit available]
☙ Sedation / Dosing steps:
1. give ketamine load and wait 60s or until patient confirms they are feeling dizzy
2. give propofol load (0.4mg/kg), and get patient talking.
☙ target = patient's speech so slurred you can't understand them. (Correlates to amnesia)
3. aliquots of propofol (1-2mL) every 30 to 120 sec prn, balancing sedation level with apnea.

PROPOFOL DOESN'T HAVE ANY SIGNIFICANT ANALGESIC EFFECT
☙ so you must [almost] always combine propofol with a second analgesic drug (e.g. ketamine)

☙ caution with propofol (very apneo-genic sedative) + fentanyl (very apneo-genic analgesic)
☙ caution with midazolam (very apneo-genic sedative) + fentanyl (very apneo-genic analgesic)

☙ ketamine dosing ranges:

☙ ≤ 0.4mg/kg - ANALGESIC ZONE ✅

☙ ~0.6 to ~1.0mg/kg - DISSOCIATIVE ZONE ("K-hole") ⛔️

☙ ≥ 1.5mg/kg - INDUCTION ZONE ✅

☙ Dissociation / "K-hole" Rescue:
☙ if patient is agitated give more anaesthetic/sedative drug of almost any kind. e.g.:

☙ midazolam 1-2mg q1 min prn

☙ propofol 30mg q1 min prn

☙ more ketamine - top up to induction zone but load with midazolam before they come back down

002 Geriatric Confusion Post-Op

Published 6 June 2021:
https://anchor.fm/jonathan-wallace-md/episodes/Geriatric-Confusion-e129f9t

Learning Objectives:
POCUS: bladder volumes:
☙ Volume = (Length x Width x Depth) ÷ 2
☙ more sophisticated formulae exist (and are a possible barrier to using?)
⁍ ask yourself: will accepting a small estimation error of the simple formula affect your clinical decision making?

1. Screening & definitions for suspected sepsis:
☙ SIRS (systemic inflammatory response syndrome) - need 2 or more: to meet "SIRS Criteria":
⁍ Temperature > 38ºC or < 36ºC
⁍ HR > 90
⁍ RR > 20 or PaCO2 < 32
⁍ WBC > 12 or < 4 or >10% band cells
☙ Sepsis Criteria = SIRS + suspected infectious source
☙ Severe Sepsis = sepsis criteria + one of:
⁍ lactic acidosis
⁍ Systolic Blood Pressure (SBP) < 90
⁍ SBP > 40 below chronic baseline (e.g. 150 -> 100)
☙ qSOFA (quick sequential organ failure assessment) - need 2 or more to predict higher mortality:
⁍ GCS < 15
⁍ RR > 22
⁍ SBP < 100

2. Management priorities for suspected sepsis:
☙ Too much IV fluid can be as bad as too little fluid
☙ POCUS will lend more precision in ordering fluids
⁍ consider scanning one or more of:
⁍ inferior vena cava ●(beginner)
⁍ lungs [for B-lines, effusions] ◾️(intermediate)
⁍ left ventricular function [PSL,A4C,S4C] ◾️
⁍ emerging standard? VEXus Scan ⬥⬥(advanced!)

☙ Order cultures (blood, ±urine, ±sputum, ±CSF, etc) as soon as the possibility of sepsis enters your brain.
⁍ Cultures aid antibiotics down the road, but delaying antibiotics = increasing mortality. Do not delay antibiotics to obtain cultures.

☙ early antibiotics:
⁍ lots of good options, depending on suspected source (or lack thereof). e.g. one or more of: piperacillin-tazobactam, ceftriaxone, imipenim, amoxicillin-clavulinic acid, ciprofloxacin + metronidazole, and more.
⁍ add vancomycin (immunocompromise suspected)

☙ Surviving Sepsis Campaign offers international guidelines. 2016 was the most recent (accepted) release.
⁍ RnR Rounds Infographic on 2016 SSC Guidelines

3. Have a very low threshold to hold / observe elderly, really young (e.g. < 3 mos), frail or suspected immunocompromised patients.

Comments? Questions? Drop us a message!

Volume I

Episodes:
001 - 025

Quick Links:

Volume 01: 001 - 025

LEARNING OBJECTIVES:

PEARLS FROM DISCUSSION:

LEARNING OBJECTIVES:

Episode 021 (Part A)

Episode 022 (Part B)

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

Description: 30 Minute Video from UBC-CPD's GPA Refresher Course (2021)

Listen to the case and discussion, and review the scans below.

This episode is a case-presentation. Please refer to Show Notes from:

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

X. Baking Soda Poisoning

LEARNING OBJECTIVES:

009 Difficult Airway

LEARNING OBJECTIVES:

008 Pharmacologic Restraints

LEARNING OBJECTIVES:

007 Suprapubic Catheter

LEARNING OBJECTIVES:

006 Cold Foot

LEARNING OBJECTIVES:

005 PEA

LEARNING OBJECTIVES:

004 Back Pain

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

002 Geriatric Confusion Post-Op

001 Intro To Series

Quick Links:

Volume IEpisodes: 001 - 025

Quick Links:

Volume 01: 001 - 025

LEARNING OBJECTIVES:

PEARLS FROM DISCUSSION:

LEARNING OBJECTIVES:

Episode 021 (Part A)

Episode 022 (Part B)

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

Description: 30 Minute Video from UBC-CPD's GPA Refresher Course (2021)

Listen to the case and discussion, and review the scans below.

This episode is a case-presentation. Please refer to Show Notes from:

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

X. Baking Soda Poisoning

LEARNING OBJECTIVES:

009 Difficult Airway

LEARNING OBJECTIVES:

008 Pharmacologic Restraints

LEARNING OBJECTIVES:

007 Suprapubic Catheter

LEARNING OBJECTIVES:

006 Cold Foot

LEARNING OBJECTIVES:

005 PEA

LEARNING OBJECTIVES:

004 Back Pain

LEARNING OBJECTIVES:

LEARNING OBJECTIVES:

002 Geriatric Confusion Post-Op

001 Intro To Series

Quick Links:

Volume I

Episodes:
001 - 025