Grand Rounds Recap 05.06.20

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Airway Grand Rounds WITH Dr. Carleton

Airway QI: Critical documentation pearls

  • If EGD is in place on arrival, type

  • Indication for intubation

  • Difficulty indicators - anatomic and physiologic

  • Route

  • Pharmacology

  • Device choice

  • Number of courses and attempts (courses are based on device/meds and correlate with cognitive approach to airway; attempts reflect the technical skill of the operator)

  • Glottic view

  • Intubation complications

  • Need for rescue

  • Who tried, who succeeded

  • Lessons learned

    • Glycopyrrolate takes 10-15 minutes to work

    • Anticipate need for suction and set it up early - know how to attach the suction tubing to the endoscope

    • Jaw thrust during endoscopy will improve your view even during endoscopy - opens up and can clear secretions

    • Have a syringe with 4% lidocaine set up and ready to augment your topical anesthesia, especially of the cords

COVID intubation practices

Deviation from standard procedures increases potential for error - have a plan for your PPE, airway equipment, preoxygenation, primary/secondary/tertiary approaches

  • Mac 4 VL with bougie is the recommended primary approach in most cases, with the caveat that a D blade may be better when the anatomy will not allow a Macintosh blade

  • Plan if you can maintain oxygenation

  • Plan if you can’t maintain oxygenation

Principles

  • Minimize aerosolization

    • Intubate in negative airflow room

    • Intubate early if getting to the point of needing positive pressure devices

      • Caveat - some are advocating for the use of HFNC with caution in selected patients as a way to avoid need for intubation (patients who are still <88% on 15lpm on reservoir mask)

    • HEPA filters for PPV if needed

    • RSI for apnea and cough prevention with supranormal doses of RSI meds (we frequently underestimate patient’s weight and there is little downside to more paralytic)

      • Sucinylcholine 2mg/kg

      • Rocuronium 1.5mg/kg

    • Clamp ETT until bag/circuit attached

    • Inflate ETT cuff before first breath, and consider connecting patient to ventilator for the first breath rather than the bag if you can for one less disconnect

    • Pre-oxygenation critical because patients drop fast

      • Keep upright/reverse trendellenberg15L reservoir mask if not critically hypoxic

      • If critically hypoxic consider HFNC at 30-60 lpm vs NIPPV using vent circuit

      • HEPA filters need to be placed between patient and circuit/bag and exhaust port of bag

      • If using facemask BMV use an OPA, lowest effective volume

      • Consider iGel as opposed to facemask for BMV if paralyzed - this effectively creates a closed circuit because the iGel allows negligible airflow around their margins

      • Apneic oxygenation probably doesn’t work in this population

      • Intubate to the upper end of depth by gender to reduce need for repositioning/disconnection

      • Minimize vent/bag disconnects

        • Deliver first breath with vent if able

        • Do not use colorimetric capnography if you have waveform

      • Stop CPR during airway attempts

        • Risk for aerosolization greatly increases

        • Patients in arrest from critical hypoxia in COVID have poor survival rates

  • Maximize first pass success - (minimizes aerosols, overcomes physiologic fragility)

    • Preplanning - room and equipment set up, personnel placement and assignment of roles

    • Closed-loop communication

    • Checklists

      • Equipment/meds/personnel roles

      • Plan A/B/C/… (A and B should be in the room always; C and onwards should be outside and acquired by a “runner” to avoid contamination)

    • Optimize safe preoxygenation

    • Positioning

      • Plane of earhole to plane of sternal notch

      • Consider intubating with HOB up to 25-30

    • RSI with supranormal paralytic dosages

    • Best device? King vision - we have these available to practice with, and so familiarize yourself

    • C-mac blades are approaching critical shortage

    • Best operator should intubate

    • Failed first-pass?

      • Continue intubation attempts vs rescue

      • If you have to bag use filters/thenar grip/lowest effective volume/OPA/under drape

      • Strongly consider iGel - allows closed-circuit ventilation and a conduit for intubation

      • Intubating through iGel

        • Blind success rate 67-74%Endoscopic success rate very high but unqualified

        • Initiate attempt at the end of a breath

        • Consider performing endoscopy through a bronch adaptor with side-port blocked

      • Have suction prepared

      • Cric if you have to

  • Limit contamination

    • Enhanced PPE/double-gloving

    • Checklist for donning/doffing vs coached donning/doffing

    • Minimize in-room personnel and assign roles

      • Attending

      • Resident

      • Nurse

      • RT

    • Runner at the door

    • Communicating outside the room? Baby monitor vs radio vs yelling through the door to the runner

    • Equipment for plans A and B inside the room

      • Cric tray, direct laryngoscope, code cart, etc outside the room

    • Aerosol mitigation - NatMat, tent, box

      • Intubation pods are arriving soon for use in both the SRU and the respiratory pod

Summary

  • Stay safe

  • Pre-plan and communicate

  • Do what’s best for the patient - use HFNC or BiPAP appropriately when needed

  • Develop systems and plans to

    • Minimize aerosolization

    • Maximize first pass success

    • Limit contamination

  • Consider early use of EGD for rescue

R1 Diagnostics - Urine Drug Screen WITH Dr. Mullen

Check out Dr. Mullen’s post on Taming the SRU for some background and additional information.

How does the urine drug screen work?

  • Samples can come from urine, hair, saliva, or blood. Urine is the most common sample obtained in the ED.

  • The type of assay that we use in the ED is an immunoassay, although mass-spectrometry is another option for confirmatory testing.

    • Immunoassays are fast and cheap, but positive results are always “presumptive” positive and require confirmation with mass-spec.

  • There are five main drugs that can be detected:

    • Amphetamines, cocaine, marijuana, opiates, PCP.

    • Other drugs such as TCAs and barbiturates may also be included on specific assays.

Drug Detection Times

  • Urine detection times can be affected by a variety of factors including patient body habitus, urine pH or concentration, drug half life, last use, etc.

  • See the post above for specific detection times of common drugs.

Cases and Learning Points

  • General Pearls

    • Results are qualitative, not quantitative.

    • Urine drug screens rarely change our ED management.

    • Only drug classes are tested for, not specific drugs (e.g. benzodiazepines but not diazepam or alprazolam specifically).

    • Thresholds and numeric cutoffs are affected by drug concentration, so there is possibility for false negative results.

    • Most importantly, there is a large amount of cross-reactivity with common over-the-counter drugs, which lead to false positive results.

  • Cocaine

    • Overall the UDS is a good test for cocaine with high specificity.

    • Stays positive for 2-4 days after use.

    • Cocaine can induce an MI through sympathomimetic surge, vasoconstriction, and promotion of thrombus formation.

  • Benzodiazepines

    • Many benzodiazepines are not detected by the UDS. It only tests for metabolites of chlordiazepoxide (Librium) and diazepam (Valium). Alprazolam, lorazepam, and clonazepam won’t be detected.

    • Sertraline and oxaprozin (an NSAID) are important cross-reactants.

  • Tricyclic antidepressants

    • There are many cross-reactants for TCAs: carbamazepine, cyclobenzaprine, diphenhydramine, hydroxyzine, and quetiapine to name only a few.

  • Opioids

    • These also have an extensive list of cross-reactants including dextromethorphan, diphenhydramine, doxylamine, verapamil.

    • You need additional testing for many of the synthetic opioids including oxycodone and methadone.

CPC thyrotoxicosis secondary to molar pregnancyWITH Drs. Wolochatiuk and Paulsen

  • Hyperthyroidism in normal pregnancy and molar pregnancy can be missed due to assuming that symptoms are from normal pregnancy (nausea, mild abdominal cramping, tachycardia/palpitations).

  • Normal pregnancy is a mildly hyperthyroid state, so have a low threshold to check a TSH in your pregnant patients with tachycardia.

  • Hyperthyroidism in a normal pregnancy can cause low birth weight, premature labor, spontaneous abortion, and preeclampsia.

  • Most of the complications of molar pregnancy (hyperemesis, hyperthyroidism, early preeclampsia) are due to high circulating levels of beta-hCG.

  • Beta-hCG has homology with the TSH hormone, thus can stimulate the downstream effects of increased TSH.

  • Molar pregnancies will presents with higher than normal levels of beta-hCG, likely will not manifest signs and symptoms of hyperthyroidism until levels are >100,000.

  • The symptoms of thyrotoxicosis in molar pregnancy differ slightly from that of a typical hyperthyroid state. Notably, no exophthalmos, pretibial edema, or enlarged thyroid.

  • Molar pregnancies often first present with vaginal bleeding, so don’t assume that your patient's tachycardia is simply due to bleeding. Go looking for concomitant thyrotoxicosis. 

  • Symptoms of thyrotoxicosis will resolve with decreasing beta-hCG levels. 

Complete molar pregnancies require D&C - check a TSH pre-operatively due to the risk of inducing thyroid storm with anesthesia induction.

R1 Clinical Knowledge - Ear Pathology WITH Dr. Ijaz

General approach to ear pain

  • Through varying etiologies such as infectious, neoplastic, etc

  • Anatomic approach, e.g. from outside to inside

  • Or some of each

Auricular hematoma

  • Due to shearing of blood vessels from underlying cartilage.

  • Hematomas larger than 2cm need to be incised and drained. Be sure to place a bolster dressing to prevent reaccumulation.

  • Some smaller studies suggest that needle aspiration may be effective, but standard of care remains I&D with bolster.

  • There is no conclusive evidence as to benefit of prophylactic antibiotics.

    • Perichondritis is a known complication. Usually due to Pseudomonas aeruginosa, often spares the lobule, and is treated with PO ciprofloxacin 500-750mg BID x one week outpatient.

Otitis externa

  • Breakdown of skin-cerumen barrier allows P. aeruginosa and S. aureus to cause infection.

  • Commonly presents with otalgia, otorrhea, pruritis, and hearing loss.

  • Be sure to visualize the tympanic membrane and verify that it is intact.

    • If the TM is ruptured then avoid ototoxic medications. Go with either ofloxacin or ciprofloxacin + dexamethasone.

  • Place an ear wick if the TM is not visible due to swelling.

  • Important for patients to follow up in 48-72 hours and know that it can take up to 2 weeks for resolution.

Malignant otitis externa

  • Complication of otitis externa, usually in a patient with poorly-controlled diabetes. 

  • IV antibiotics and ENT consultation are a must.

  • CT head or other imaging may be indicated if you suspect a brain abscess or DVST, which may further complicate malignant OE.

Acute otitis media

  • Common causes include S. pneumoniae, H. flu, M. catarrhalis.

  • General approach is “wait and see" instead of immediate abx, unless there are red flags:

    • < 6 months old

    • 6-23 months with bilateral AOM

    • > 6 months with severe pain, fever > 102.2, or symptoms > 48 hours

  • First line abx amoxicillin, second line amox + clavulanate

R4 Sim - Crush Injuries and Hyperkalemic Arrest WITH Drs. Golden, Ham, and Spigner

Crush Syndrome

  • In general, there is no good evidence for any of the management strategies for crush syndrome. Management is largely based on animal studies, expert opinion, and anecdotes.

  • Crush syndrome is cause by compression of muscle that leads to release of myoglobin, electrolyte derangements, edema, and volume loss.

    • With release from the compressive force there is reperfusion.

    • This all causes renal failure, acidosis, dysrhythmia, and shock.

    • Decline can be precipitous.

    • Prior to 1940 crush syndrome was virtually universally fatal.

  • Early studies included

    • Rabbit models of alkaline rehydration to prevent renal failure in induced acidosis.

    • Urine alkalinization following the bombing of London in WW II.

    • Mannitol or mannitol/bicarbonate “cocktail” to protect against myoglobinuric renal failure.

  • Bicarbonate and mannitol have been studied in retrospect, but no clear benefit was detected. This contradicted prior animal studies and lower quality evidence.

  • Scene safety is paramount.

    • There is a large body of knowledge surrounding structural collapse incidents.

    • Consider airborne contamination (dust, asbestos, etc.).

    • Liquid and biohazard contaminants

    • Sharps/cut, electrical, fire hazards

    • Temperature and lighting

  • Despite lack of high-quality evidence, a reasonable approach to such incidents includes:

    • Scene safety, PPE, environmental optimization

    • Primary survey to assess life threats

    • Consider indications for amputation if necessary for extrication, or placement of tourniquets to crush limbs prior to extrication.

      • Dr. Otten recommends adding a tourniquet if the patient has been entrapped longer than one hour.

    • Resuscitate before release with volume +/- bicarbonate.

      • “Crush injury cocktail” recommended by Dr. Gonzalez with FDNY: 1.5L 0.9% NS +/- 1 amp bicarb and 10mg mannitol in each liter

      • Ongoing volume post-extrication, urine pH > 6.5, mannitol if urine < 200-300 ml/hr, consider early dialysis for oliguria

      • Dr, Otten recommends volume resus before release and add bicarb.

    • Hemodynamic monitoring for cardiac dysrhythmias or shock

  • Hyperkalemic arrest

    • This is a possible complication of crush syndrome and as such should be anticipated.

    • Hyperkalemia falls into broad categories of mild, moderate, and severe from 5.5-6, 6.1-6.9, and >7, respectively.

    • There are characteristic EKG changes that correlate well with adverse outcomes including PR prolongation, QRS widening, 2nd degree heart blocks, and junctional rhythms.

    • Treatment principles include

      • Membrane stabilization

        • Calcium gluconate or chloride; only chloride is carried on Air Care currently. Take great care to avoid extravasation if you administer it through a peripheral IV.

      • Transcellular shift

        • Insulin/glucose

        • Albuterol

        • Epinephrine - works through a similar beta-agonistic mechanism and is also useful as a pressor.

        • Sodium bicarbonate - only useful if the patient is also academic, but in reference to crush syndrome this may also be helpful even outside of hyperkalemic arrest.

      • Removal

        • In the case of crush syndrome with rhabdomyolysis and acute renal failure, dialysis is the go-to for removal.