Airborne Isolation / COVID19 Intubation Checklist

AIIC [pdf]

AIIC [image]

more pearls: make sure cuff is inflated prior to manual ventilation. attach viral filter directly to ETT, if circuit disconnection needed, disconnect circuit on vent side of filter.

References: Zuo 2020, Wax 2020, Weingart 2020, ecuus 1 and 2, Farkas & Thomas 2020

CDC 5 min video on proper donning/doffing, pdf, pulmcrit cheat sheet

 

CDC CV19 Discharge Instructions

LAC DOH CV19 Discharge Instructions

 

Scott’s BVM-on-NIV mask oxygenation setup (6 min vid)

 

Ketamine-Only Breathing Intubation

This 9 minute video demonstrates the strengths and weaknesses of an intubation strategy that relies on dissociation with ketamine.

The essential strength, compared to RSI, is that a breathing technique keeps the patient breathing during laryngoscopy, which transforms the procedure from high-adrenaline to highly controlled. You see in this video that my (fabulous) resident was able to take his time, try different blades, slowly advance and adjust while using view optimization techniques as the patient continued to breathe. This is an extremely powerful way to add safety to the riskiest procedure commonly performed in acute care. We would have been able to carry on with his attempts for longer, had we not been inconvenienced by the arrival of a trauma patient.

Keeping the patient breathing during intubation has a long history in emergency medicine, starting with the brutal and often unsuccessful blind nasal intubation, which, fortunately, is now seldom performed. Many of us learned to do operating room style awake intubation, which relies on thorough local anesthesia using atomized/nebulized/topicalized/regionalized lidocaine, so the patient can remain truly awake and breathing during the procedure. Lidocaine-focused awake intubation is a fabulous technique that requires expertise and equipment not available to all acute care providers, but also–depending on your level of skill–time and patient cooperation. Time and cooperation is something we may not have downstairs or on the side of the road,* but what we lack in time and cooperation, we can make up for in ketamine.

When we use dissociative-dose ketamine to do the heavy lifting in allowing the patient to tolerate laryngoscopy, we obviate much of the needed topicalization expertise/supplies, abbreviate the needed time, and add cooperation with ketamine, cooperation in a vial.  The patient becomes dissociated, breathing but unconscious, which is why I use the term breathing intubation rather than the much more accepted term awake intubation to describe it.

Many patients who receive dissociative-dose ketamine without a paralytic will have some muscle rigidity, and some will develop laryngospasm (which is glottic muscle rigidity).  The patient in this video had some rigidity, which resolved and was not a problem, and this is usually the case. But patients who get ketamine to facilitate laryngoscopy are at much higher risk than procedural sedation patients (who are not having their airway instrumented) to develop laryngospasm and occasionally jaw rigidity, which, together, can cause an immediately dangerous cannot intubate cannot ventilate scenario. Anytime KOBI is being undertaken, a paralytic must be immediately available, ideally drawn up in a syringe, so that the procedure can be converted to a paralyzed technique at any point.

How KOBI fits into our expanding airway toolkit is expertly described by Andrew Merelman and Michael Perlmutter in this WJEM paper.

 

 

 

*some airway experts disagree

 

Postoperative Neck Hematoma

Postoperative neck hematoma is not often discussed in emergency medicine but behaves a lot like neck trauma, because it is neck trauma. These patients should be managed with a high-resource approach and discharged reluctantly, after careful deliberation.

Adapted from Bittner, MD.

The Paper Throat: A Lo-fi, DIY Laryngoscopy Simulator

 

Laryngoscopy involves a series of unnatural movements and hand-eye skills that are not easily learned while simultaneously caring for a dying patient. The Paper Throat is a low fidelity but high yield direct laryngoscopy training tool that is easily assembled and practiced. The hope is that routine use will generate laryngoscopy muscle memory so that training providers can focus on other aspects of airway management when called upon to intubate IRL.

Conceived and produced by Jonas Pologe.

Pulse Ox Lag

Folks put a lot of stock in the pulse oximeter, as they should, because the pulse ox is an awesome feat of engineering and patient safety. But the pulse ox lags.

Here, the inestimable Dr. Jonas Pologe (rhymes with apology) demonstrates pulse ox lag with a breath hold.

Breath hold starts at 0:11, sat is 100%
Saturation starts to drop at 0:48
Breathing commences at 1:25, sat is 82% at this point
Saturation continues to drop until 1:46, then recovers from its nadir of 77%
At 1:58, saturation reaches 100% again

 

Lessons:

1. When the sat is on its way down, the patient is more hypoxic than the pulse ox shows. This is another reason why, when laryngoscopy is not producing an acceptable view of the glottis, you should come out and reestablish ventilation/oxygenation earlier than you think. A more important reason to come out and bag early is described here.

2. When you are reestablishing oxygenation (using a bag mask, laryngeal mask, or endotracheal tube), do not use the pulse ox to judge the adequacy of ventilation, use capnography. That means the capnogram should be attached to the bag mask/LMA/ETT before the first breath is given. If the capnogram is good, ventilation is good, and the pulse ox will catch up, so relax and stop bagging so quickly.

When RSI isn't the Right SI

When RSI Isn't The Right SI.001

Rapid sequence intubation, the simultaneous administration of a paralytic and induction agent immediately followed by laryngoscopy, provides the optimal view of the glottis and prevents emesis. RSI is the best strategy for most patients who require intubation, but not all.

When you’ve decided to intubate, first maximally preoxygenate. If the patient will not cooperate with your preoxygenation plan, even after you’ve asked nicely, that’s your cue to add cooperation in a vial, ketamine, and then oxygenate, before you push the paralytic and intubate. This is delayed sequence intubation. Otherwise, carry on with preoxygenation, and consider a couple of special situations.

The first is the patient who is about to arrest–obtunded, no blood pressure. Any induction agent will cause sympatholysis which, along with the transition to positive pressure ventilation, may precipitate arrest, so ideally we would avoid both while the patient is in the state of nearly arrested. Resuscitate aggressively with fluids, vasoactive drips and treatment of the underlying problem for as long as you can before intubating. If you must intubate the patient who is obtunded with no blood pressure, the safest way to do it is often without any drugs at all, while the patient continues to breathe. If you have to give meds, dose sedatives low and paralytics high.

The next special situation is the patient who has a severe oxygenation or ventilation deficit. The severe oxygenation deficit patient saturates less than 90% on 100% NIV; the severe ventilation deficit patient is compensating for a severe metabolic acidosis, e.g. DKA with pH 6.7. In patients with a severe oxygenation or ventilation deficit, even a brief period of apnea is very dangerous, and since paralysis is certain to cause apnea, it stands to reason that paralysis may not be the best approach. However, these patients are very ill, so conventional awake technique, which requires time and cooperation, will not work well. If only there were a drug that would immediately render the patient tolerant of laryngoscopy, while ventilation and airway reflexes are preserved.

Ketamine-supported intubation, KSI, is pushing an induction dose of ketamine over 20-30 seconds, then performing laryngoscopy. KSI is awake intubation with minimal or no local anesthesia, or, if you prefer, RSI without paralysis.

By omitting the paralytic, KSI carries a chance of two harms: suboptimal view of the glottis, and emesis/aspiration. I address these harms in detail in this discussion; the advantage in glottic exposure offered by paralysis is less significant in the era of video laryngoscopy, which almost always provides a great view of the cords, and the risk of emesis/aspiration is very small most of the time. In any case, these harms must be weighed against the harm of apnea for the patient in front of you. Others have described a similar strategy, augmenting ketamine with etomidate as necessary.

The last and most important special situation is high concern for difficult laryngoscopy. You assess all your endotracheal tube-requiring patients for difficult laryngoscopy, either intuitively or explicitly, and most of the time, you think, I got this, in which case, carry on with RSI like you always do. But if you think it is likely that laryngoscopy will fail, and the patient is presently benefiting from their own ventilatory efforts, abolishing those efforts with RSI may not be the best choice.

Even in scary laryngoscopy cases, RSI is probably still optimal if the patient is high risk to vomit (has been vomiting, upper GI bleed, bowel obstruction). In these scenarios, the protection against emesis afforded by paralysis is compelling, so proceed with RSI, but use a double setup, with your partner on standby, ready to cut the neck. Keep the head of the bed up and drop an NG tube in beforehand if you can.

The patient whose airway is a lawyer’s dream and isn’t a particular risk to vomit is ideally intubated without a paralytic, while continuing to breathe, awake intubation. Awake intubation has two pharmaceutical arms: local anesthesia, and systemic sedation. The more cooperative the patient and the less urgent the airway, the more you can rely on local anesthesia. So if you have time and cooperation, dose glycopyrrolate or atropine, then generously nebulize, topicalize, and atomize lidocaine, then you can slowly, carefully do your laryngoscopy, or flexible endoscopy, or whatever you want, as the patient is awake and breathing. In the OR, where patients and physicians are stable and cooperative, patients with concerning airways are intubated with minimal or no sedation at all, which affords an enormous margin of procedural safety. Patients being intubated in the ED are of course neither stable nor cooperative, but a similar degree of safety can be achieved using ketamine: the less time and less cooperation, the less lidocaine, the more ketamine.

In the extreme version of the emergency department awake intubation, give induction dose ketamine and go: KSI. Consider KSI for your severe oxygenation/ventilation deficit patients, but also when you are concerned that laryngoscopy is going to fail and the patient won’t cooperate with, or you don’t have time for, a more civilized, operating theater-type awake intubation. Have a paralytic ready in syringe, in case you want to convert to RSI at any point, and incorporate a double setup component to your approach, because your concerns about laryngoscopy might turn out to be well-founded.