Delayed Sequence Intubation

Delayed Sequence Intubation

We often instruct with absolutes. “Never let the sun set on a pleural effusion.” “You’re not dead until you’re warm and dead.” “Never intubate an asthmatic.”

Well, often medical decisions exist in a much less dichotomous realm. It is great to have strong opinions and a resolute view of the goals; however, being adept at generating positive results with a terrible set of variables is what we as EM physicians must do.

In the past we have covered Asthma management several times (MDIs vs Nebs, Hydration Status, and more) and often declare the goal of not intubating those patients and doing everything possible, like throwing the “Kitchen Sink” at them.

Kitchen Sink

But… what if things aren’t going well?

And, by not going well, I mean the patient is actively trying to die. Picture if you will…

A young male who presents with severe distress. The Kitchen Sink gets ordered, but the child’s distress leads him to be anxious and prevents him from cooperating so that the therapies are now ineffective. Additionally, his severe diaphoresis prevents maintaining an IV. His mental status quickly changes from extremely anxious to terrified to combative. You enlist the aide of all of your ED resources, but despite everyone’s best efforts, he continues to rapidly worsen, objectively. His Heart Rate, which was rapid, now is decreasing into the 80’s. His Pulse Ox on Facemask is 75%. There is no time to change your pants… you’ll have to do that later.

Additions to the Kitchen SinkKetamine

  • Ketamine
    • I have proclaimed the utility of Ketamine in the past (Hypercyanotic Spells)
    • Ketamine is often noted to improve pulmonary compliance and decrease airway resistance.
    • It is also noted to reduce bronchospasm.
    • The bronchdilatory effects can be seen at doses below those that lead to dissociation.
    • There are several case series / reports of the use of ketamine being safely used even in unintubated children as part of the asthma therapies.
    • Unfortunately, when studied more rigorously, ketamine has not proven to lead to improvement over standard therapies in those with “moderately severe asthma exacerbations.” (Allen, 2005)
      • This study used 0.2mg/kg bolus followed by 0.5mg/kg/hr.
      • This may not be an adequate dose.
      • Naturally, it is only one study… so hard to make declarations yet.

Obviously we would like to have the patient optimally preoxygenated prior to intubation with appropriate nitrogen washout. But, in this case, the child is going to need positive pressure to do so… as his Sat is 75% on a facemask. What do you do now?

You can use a BVM with PEEP valve, but he won’t likely tolerate that easily, so you’d have to either restrain him or sedate him… or both. And then, that still won’t be very easy to do on his very sweaty face.

You can elect to just “go for it” and perform RSI. Hmmm…. I definitely would not advocate for this unless you want to deal with a bradycardic arrest concurrently.

Or you can slow down the process of Rapid Sequence Intubation…

  • Delayed Sequence Intubation
    • As coined by Dr. Weingart, Delayed Sequence Intubation can offer a safe alternative in such confined situations.
    • The key point here is that you have decided that the patient needs to be intubated, but you need to adequately preoxygenate the patient, but the patient is not able to cooperate with NonInvasive Ventilation (NIV).
    • Here is where the Ketamine (Special K to the rescue) comes in.
      • The ketamine (1 – 2mg/kg IV) will dissociate the patient but allow them to maintain the protective airway reflexes.
    • Now the patient will cooperate with the NIV and the positive pressure can help adequately preoxygenate the patient to a safe point where your act of intubating won’t be as heroic (also known as dangerous).
    • While continually assessing the patient’s clinical status (seriously), you have your team assemble all of your airway tools.
    • Once the patient is oxygenating well and has remained hemodynamically stable, you administer your paralytic and pass the endotracheal tube on the first attempt (honestly, some good luck should be due to you by now).
    • For an enligthening and fun conversation between Dr. Weingart and Dr. Gill Click here.

Naturally, these aspects of the Kitchen Sink really reside under the Kitchen Sink and should seldom be needed, particularly for children. That being said, it is really a good feeling to know where to find those tools when all else seems to be failing rapidly.

Thank you Dr. Weingart!

Schneider ED, Weingart SD. A Case of Delayed Sequence Intubation in a Pediatric Patient with Respiratory Syncytial Virus. Annals of Emergency Medicine. 2013; 62(3): p278.

Weingart SD. Preoxygenation, Reoxygenation, and Delayed Sequence Intubation in the Emergency Department. Journal of Emergency Medicine. 2011; 40(6): pp 661-667.

Allen JY, Macias CG. The Efficacy of Ketamine in Pediatric Emergency Department Patients who Present with Acute Severe Asthma. Annals of Emergency Medicine. 2005; 46(1); pp 43-50.

Denmark TK, et al. Ketamine to Avoid Mechanical Ventilation in Severe Pediatric Asthma. Journal of Emergency Medicine. 2006; 30(2): pp 163-166.

Petrillo TM, et al. Emergency Department Use of Ketamine in Pediatric Status Asthmaticus. Journal of Asthma. 2001; 38(8): pp 657-664.

Rock MJ, et al. Use of Ketamine in Asthmatic Children to Treat Respiratory Failure Refractory to Conventional Therapy. Critical Care Medicine. 1986; 14(5): pp 514-516.


Sean M. Fox
Sean M. Fox
Articles: 583


  1. […] the utility of Magnesium.  In addition, we have covered mechanical ventilation for asthma and how Delayed Sequence Intubation may be a useful tactic.  One aspect that we have not yet covered, though, is the utility of […]

Comments are closed.