Emergency Medicine Education

4C’s of mental toughness:

1. control: a tendency to feel and act as if one is influential
2. commitment: a tendency to involve oneself in rather than experience alienation from an event
3. challenge: belief that life is changeable and to view an experience as an opportunity rather than a threat
4. confidence: a strong sense of self-belief and faith regarding one’s ability to succeed

-imperturbability (emcrit): https://emcrit.org/emcrit/imperturbability-william-osler-resilience-and-redefining-mental-toughness/

-no fluffy language in resus room (emcrit, Cliff Reid): https://emcrit.org/emcrit/learning-speak-resuscitese/

-“work-life balance” does not exist:
http://journal.frontiersin.org/article/10.3389/fped.2014.00026/full

-make clinical rules for yourself and stick to them. As soon as you deviate from your own rules, you will miss something.

-quick dispos are important to keep north side open for more pts, BUT if the pieces of the puzzle are not falling together (pt not responding to tx as expected, unexpected exam/labs/etc), STOP THE DIAGNOSIS MOMENTUM and START OVER. **Do not try to force the puzzle pieces to fit when they do not**

–

Resources

https://emlyceum.com/

-determine if bleeding is:
—low risk (easily compressible and not in a life-threatening space)
—moderate risk (stable GI or retroperitoneal? bleed)
—high risk (ICH, bleeding into pericardium, aortic dissection, spinal epidural hematoma, or ocular/hyphema?, unstable GI or retroperitoneal bleed)

-determine time of last ingestion of the NOAC – if >12-14 hours ago, the anticoagulant effects have worn off and there is little utility in reversal
-have a low threshold for activating MTP

For Xa inhibitors apiXaban (eliquis) or rivaroXaban (xarelto)

First line: 4-factor PCC (Octaplex, Beriplex, Kcentra) at a dose of 50 IU/kg up to 2,000 units.

Note that if you highly suspect a Xa inhibitor intracranial bleed before obtaining a CT head, it is reasonable to give 1,500 units of 4 factor PCC on speculation.

Second Line: Tranexamic acid, 1 gm over 10 minutes and then 1 gm over the next 8 hrs if 4-factor PCC is ineffective.

For Direct Thrombin Inhibitor (DTI) Dabigatran (pradaxa)

First Line: Idarucizumab (Praxbind)

For antiplatelet Ticagrelor (plavix)

-give ddAVP, consider platelet transfusion

High risk procedures for patients on DOACs include lumbar puncture and subclavian central line.

Low risk procedures for patients on DOACs include paracentesis, thoracentesis and non-subclavian central line.

Dose reduction: apixiban/eloquis, enoXaparin/lovenox, and dabigatran/pradaxa require dose reduction for renal excretion and age (rivaroxaban/xarelto does not)

• don’t focus on the medical, but rather on what is pt-centered: function, quality, and time of remaining life
• summarize condition with a bottom-line: ‘getting worse,’ ‘not going to improve,’ ‘dying and time is likely very short.’

A Protocol for O2 Escalation (goal sat low 90s, unless end stage lung disease):
1. up to 6L nc (40% FiO2). Treat pleuritic pain to prevent splinting.
2. 12-15L facemask (50-60% FiO2)
3. HFNC if available. Use ROX index to determine failure.

Who to definitely intubate? End organ injury/hypoperfusion (ex elevated lactate), AMS, hypotension, respiratory acidosis/hypercapnea (w/o hx of CHF or COPD)

CPAP failure: PEEP >8? and 100% FiO2, not cooperative

Use ROX Index to determine failure of HFNC:
ROX = (SpO2/FiO2) / RR
ROX < 4.88 – intubate
failure with trial of HFNC @2h: ROX < 2.85,     @6h: ROX < 3.47,      @12h: ROX < 3.85

Note that PF ratio is meant for intubated pts (FiO2 is most accurate on vented pt).

From literature:

Noninvasive ventilation:
-NIV may be useful in preventing ETI if concomitant COPD or CHF – NIV shown to work for hypercapnea

Headache

• Killers (11): SAH, ICH, meningitis, ENT/facial infection, CO poisoning, temporal arteritis, venous sinus thrombosis, cervical artery dissection, glaucoma, IIH, preeclampsia
• Tx sequence: ivf, metoclopramide + benadryl, toradol, decadron. Sphenopalatine block.

Chest Pain

• Killers (6): ACS, PE, ao dissection, tamponade, PTX, PNA
• STEMI equivalents: aVR elevation, deep inverted/biphasic Ts (Wellens), ant precordial STD (posterior MI), hyperacute ST slope (deWinter), modified Sgarbossa in LBBB, *isolated TWI or STD in aVL*
• Tx tips: ASA immed, NTG ointment, morphine worsens outcomes
• Tips: pain above & below diaphragm = dissection w/u,

Syncope Plus

• Structural/electrical heart disease or FH: arrhythmia
• Exertion: HOCM
• Young woman with abdominal pain: ectopic pregnancy
• Older male with abdominal/flank pain: AAA
• Sudden severe HA: SAH
• Malignancy, SOB: PE

Dyspnea

Killers:

Agitated patient

• Sequence: Must be undressed. Needs met? Verbal de-escalation, show of force, offer “something for the nerves” po, chemical + physical restraints (need to document & remove asap)
• give home meds if possible, haldol 2-5mg IM +/- ativan 1-2mg IM, quetiapine/seroquel, olanzapine/zyprexa (safest for QTc)
• Tips: avoid bzd in elderly and autistic, avoid antipsychotics if suspect tox, avoid benadryl in elderly

Procedural sedation
midazolam 0.05mg/kg IV, or haloperidol 5mg IV pretreatment to prevent recovery agitation after ketamine

Sick patient

• eval: iv x 2 (io), O2, monitor, A-B-C-Dextrose
• shock: empty tank (hypovolemia/hemorrhage), leaky tank (anaphylaxis, sepsis), pump failure (cardiogenic, dissection), obstructive (PE, tamponade)
• Hs (5) & Ts (6): H’s, hypo/hyperK, hypoxia, hypovol, hypothermia; TPTX, tamponade, thrombosis ACS, thrombosis PE, tox, trauma
• post ROSC (3): BP, EKG, gas, pressor
• calling codes: unwitnessed arrest, nonshockable rhythm, no ROSC, age >60, pH<7, unknown downtime, pocus echo. K>12 futile.

Intubation

• airway H&P (each with high LR+ for difficult airway): hx difficult tube, snoring, LEMON (Look externally [beard, retrognathia, obesity], Eval 3-3-2, Mallampati, Obstruction, Neck mobility), inability to exaggerate underbite (new!)
• prep: SOAPME, position is ramped up, +/- push-dose pressor at hand (+bicarb if also severely acidotic), post-tube sedation +/- pressors hung, voice plan and backup to team

SCD patient

• no O2 if not hypoxic!
• no fluids if euvolemic (esp in AChS)! Only give D51/2NS, hypotonic fluids prevent further sickling. Bolus only for septic unstable patients.

Before discharge

• have vitals normalized?
• PO challenge? Road test?
• review labs, imaging, & documentation – Does everything make sense? Any incidental findings?

–elbow technique (new!)

–self-reduction

–scapular rotation: scapular tip pushed medially, acromion inferiorly (open-book)

–vertical pull (Spaso): lift arm vertically, fully externally rotate, and pull toward ceiling

–external rotation (Kocher): slowly rotate externally with humerus parallel to torso, then maintain externally rotate until cross midline

–lateral extension (Milch): while externally rotated and providing traction on the humerus, slowly extend laterally until above 90′

–traction-countertraction: tie sheets so that traction is pulled on humerus while body in place

–passive traction (Stimson): apply weight to extremity while pt prone (for young healthy pts only)

–oscillating method (Fares): while keeping traction, oscillate up and down while slowly extending laterally. Best if kept extremity in external rotation.

–up-close-and-personal (Cunningham): pt’s hand on your ipsil shoulder, put downward pressure on their elbow. With free hand, massage biceps and rotator cuff muscles.

–POSTERIOR dislocation traction-countertraction:

–INFERIOR dislocation traction-countertraction:

PECARN 2019 for infants 29d-60d workup (small trial):

***from 2013 EBM

Burn transfer criteria:

3 mL of lactated Ringer’s solution x weight in kilograms x % of body surface area burned (partial- and full-thickness burns)

Trauma in pregnant pts
–have a low threshold for giving Rhogam

-types II & III may disrupt cribriform plate – look for CSF rhinorrhea

Traumatic iritis = inflam of ciliary body
-cycloplegic (homatropine. Relieve photophobia) +/- topical steroids (ONLY optho can Rx)

Globe rupture – elevate bed >30′ to reduce ocular pressure and prevent further extravasation (avoid sux if intubating – incr IOP)
-give abx prophyl

Infraorbital anesthesia is associated with this fracture due to injury to the infraorbital nerve. Other findings on physical exam include enophthalmos due to herniation of globe contents before the onset of edema. Diplopia on upward gaze occurs with entrapment of the inferior rectus muscle leading to binocular diplopia 

7 areas of ICH on CT Head: spinal cord, midbrain, 4th ventricle, lateral ventricles, gyri and sulci, gray-white matter differentiation

Spinal shock = cord concussion

3 types of pelvic fractures:
– lateral compression (T-bone MVC/pedestrian hit from side)
—look for vertical fracture of sacrum
—no benefit from pelvic binders
—mostly “elderly” (age >55) pts at risk of bleeding – calcified vessels break easily
—if suspect bleeding or binder already placed, benefits generally outweigh potential harm of overreduction so do not remove
– AP fracture (head on MVC)
– vertical shear (fall)

-Send serum osmolality!
-determine fluid status: hypo-, eu-, or hypervolemic
-Use formulas!

Hyponatremia
-if asymptomatic, fluid restriction. Don’t give fluids!
-if altered/seizing,
-max rate of correction = 8 mEq/h
-Goal: <10-12 mEq total increase in 24h

Hypovolemic hyponatremia mechanism = decreased  arterial perfusion of kidneys -> ADH secretion -> reabsorption of free water
–fix the underlying problem: volume replete

Hypervolemic hyponatremia (CHF, cirrhosis) mechanism = depleted intravascular volume despite excess extravascular volume = decreased effective arterial perfusion of kidneys -> ADH secretion -> reabsorption of free water

Euvolemic hyponatremia
-SIADH – inappropriate excess ADH secretion
-psychogenic (excess free water intake), beer potomonia + “tea and toast syndrome” (inadequate solute intake)

Hypernatremia
-bolus NS if shock/hypoperfusion
-replace total body water (TBW) deficit

1. Treat Neurologic Emergencies Related to Hyponatremia

In the event of a seizure, coma or suspected cerebral herniation as a result of hyponatremia, IV 3% hypertonic saline should be administered as soon as possible according to the following guide:

1. Administer 3% hypertonic saline 100-150cc IV over 5-10min
2. If the patient does not improve clinically after the first bolus, repeat a second bolus of hypertonic saline.
3. Stop all fluids after the second bolus of hypertonic saline to avoid raising the serum sodium any further

What if hypertonic saline is not readily available? –> Administer one ampule of Sodium Bicarbonate IV over 5min.

Ringer’s lactate has a sodium concentration of 128mmol/L which will be more isotonic to the hyponatremic patient. Although never shown in clinical studies, administering Ringer’s lactate will likely result is a slower rise in serum serum sodium than Normal Saline, and therefore have a lower risk of potentiating osmotic demyelination syndrome. Ringer’s lactate is therefore recommended by our experts as the fluid of choice for resuscitation of the hypovolemic/hyponatremic patient.

Practical Approach to the Differential Diagnosis of Hyponatremia

1. Look at chief complaint: look for conditions which can increase output or decrease intake such as vomiting and diarrhea, pain or altered level of awareness
2. Review Medication List: look for those that cause SIADH, especially thiazide diuretics and SSRIs; patients who have been on chronic steroids may have adrenal insufficiency
3. Evaluate PMHx: Look for history of end organ failure (CHF, liver failure and renal failure) or cancers (a cause of SIADH)
4. Lab work: glucose (hyperglycemia), potassium (hyperkalemia may suggest adrenal insufficiency), TSH (hypothyroidism)

Note: if by history the hyponatremia is acute, it is safe to correct it quickly. The patients who are at risk of central pontine demyelinolysis are those whose hyponatremia is chronic.

Other lytes concepts:
-replete low ionized Ca after PRBC transfusions (contains citrate)
-alkylosis (ex: primary hyperventilation) causes more Ca from its ionized state to be bound to albumin (may develop signs of hypoCa)
-severe hypocalcemia -> cardiovascular collapse (loss of contractility/inotropy)
-hypocalcemia -> QTc prolongation -> torsades
-CaCl2 = 3x more ions than Ca-gluconate

-beware of further increasing serum bicarb for a pt that is hypoventilating (ex CHF exacerbation) – will worsen compensatory respiratory acidosis (hypercarbia). This is why MICU gives acetazolamide to CHF pts on BIPAP
-Dialysis dysequilibrium syndrome (dizziness during dialysis) – due to the rather rapid removal of BUN, which has an osmotic effect
—–serum osmolality = 2x(Na) + glucose/18 + BUN/2.8

0.9% NS = 154 mEq Na
0.45% NS = 77 mEq
plasmalyte = 140 mEq
LR = 128 mEq
D5W = 0 mEq
3% hypertonic saline = 513 mEq (3 / 0.9 = 3.33 x 154mEq)

References:
https://emergencymedicinecases.com/episode-60-emergency-management-hyponatremia/
https://coreem.net/core/hypocalcemia/

Assess alignment of the vertebrae as assessed by intact anterior spinal, posterior spinal, and spinolaminar lines (it should be possible to draw a smooth curved line touching all 7 cervical vertebrae at each of these locations without interruption).

Any soft-tissue swelling or disruption of normal lines, in the setting of trauma, suggests occult fracture or ligamentous injury.

In children under 8, ligamentous laxity of the upper C-spine can cause anterior displacement of C2 on C3, a normal variant called pseudosubluxation, which can be confused with an acute ligamentous injury. Up to 4 mm is normal in children <8yo.
—Check Swishuk’s line (the line drawn in the additional image between the anterior aspects of the spinous processes of C1 and C3—in pediatric pseudosubluxation, it will be within 2 mm of the anterior aspect of the C2 spinous process).
((((pic in case 7 additional images))))

In general: If both spinal columns are disrupted, the spine will move as 2 separate pieces, and there is high likelihood of that movement’s causing or worsening spinal cord injury. If only 1 column is disrupted, the other column resists further movement, and the likelihood of a spinal cord injury occurring is less and depends on the strength of the intact ligaments.

Unstable fractures: Jefferson Bit Off a Hangman’s Thumb: Jefferson burst fracture (C1), Bilateral facet dislocation, Odontoid fractures (C2), Hangman fracture (C2), Teardrop fracture

• Jefferson burst fracture: C1, axial load
• Odontoid fracture: high cervical pain radiating to the occiput
• Hangman fracture: C2, extreme hyperextension

The Hangman’s fracture, or spondylolysis of C2, occurs when the cervicocranium (skull, atlas, and axis) is thrown into extreme hyperextension as a result of abrupt deceleration. Bilateral fractures of the pedicles of the axis (C2) occur with or without dislocation. Although a hangman’s fracture is unstable, cord damage is often minimal because the AP diameter of the neural canal is greatest at the C2 level, and the bilateral pedicular fractures permit the spinal canal to decompress itself.
-Deficits on neurologic exam are more likely due to associated head injury or vertebral artery injury than to damage to the spinal cord directly
-concomitant C spine injuries (esp C1-C3) are common – look for them
-immobilize and consult spine specialist ASAP

• A flexion teardrop fracture results when severe flexion forces cause anterior displacement of a wedge-shaped fragment (resembling a teardrop) of the anteroinferior portion of the involved vertebral body. This fracture involves complete disruption of the ligamentous structures at the level of the injury. This leads to a highly unstable fracture.

Flexion injuries can cause unstable injuries such as atlantoaxial dislocation, bilateral facet dislocations, and teardrop fractures, as well as stable injuries, such as spinous process avulsions (e.g. clay shoveler’s fracture) or simple wedge fractures.

Facet dislocation:
–Unilateral facet dislocations typically present with ipsilateral radiculopathy (the affected superior facet displaces into the neural foramen) and less than 50% anterior vertebral body displacement on lateral radiographs
—considered stable, but a significant percentage have associated cord injury
—Head often held deviated away from the side of the injury, unable to straighten
—may be palpable malalignment of spinous processes
–Bilateral facet dislocations often have frank neurologic deficit with greater than 50% vertebral body displacement on x rays
—unstable, majority have cord injury
—may have bony stepoff
-mgmt: immobilize in hard collar, but if spine locked, do not force it. Use sandbags, towel rolls, and tape instead
-call spine specialist (NSG) for closed reduction in ED prior to going to OR
-perform serial neurologic exams – neurologic deficit may worsen after closed reduction (from disc protrusion)
(((pic case 2))))

C2 (axis) fracture
-body:
-odontoid/dens fractures: Types I (tip), II (base), & III (body of C2)
—type III is unstable (involves C2 ring)
—consult ortho/NSG for mgmt for all of these
-The lateral masses of C1 should align perfectly with the lateral masses of C2 (blue lines). The medial aspect of the C1 lateral masses should be equidistant to the odontoid (letter A – in this case asymmetrically widened on the right). A distance of >7mm from a C1 lateral mass to the dens indicates transverse ligament rupture or C1 burst (Jefferson) fracture
-immobilize, MRI
(((pic case 3, diagnosis))))

Transverse spinous process fracture:
-there is a significant association between transverse process fractures and intraabdominal injury (given high energy mechanism), so these fractures should be regarded as possible markers for abdominal organ injuries, even though the spine is stable
-obtain CT abd/pelv with recon of T/L spine to look for intraabd injuries and other associated spine fractures
-if isolated, pain control and early mobilization

Lower spine fractures:

-it is important to distinguish a burst fracture from a simple compression fracture. In a simple compression fracture, the compression should only involve the anterior aspect of the vertebral body. In a burst, the posterior vertebral body is also compressed (and thus more likely to injure spinal cord).
–unstable if neuro deficit, >50% loss of vertebral body height, >20 degrees angulation at the thoracolumbar junction, canal compromise
—–dispo determined by ability to control pain. These pts can go home with TLSO brace or to rehab
–If there is loss of height of the posterior portion of the vertebral body or retropulsed bone, the diagnosis is burst fracture. Burst fractures are unstable!