Imagine this: you are a critically ill patient suffering from sepsis. You are in severe respiratory distress from pneumonia and have become somewhat groggy and slow to answer questions. The medical team treating you appropriately decides that you require intubation to protect your airway and provide ventilatory support. The team properly prepares you for intubation and administers 100 mg ketamine and 70 mg rocuronium. They successfully intubate you and set the mechanical ventilator. At this point, your condition is significantly better as your work of breathing is improved and your airway is protected. But after about 20 minutes on the ventilator you start to regain awareness. You have little recall of the events prior to intubation due to your illness and the use of sedatives. You notice a pain in your throat and want to gag and vomit. You feel that you are breathing but cannot seem to control it yourself. The pain in your throat is worsening to the point where you feel like something is stuck in it. You try to reach toward your mouth but you can’t move at all. Helplessness and pain overcome you and primal fear sets in. You are more aware now than before intubation as the pain has cause you to become alert. The medical team continues to believe that you are comfortable and sedated as you lie motionless on the bed. But they do notice that your heart rate has increased substantially from 120 prior to intubation to 180 now. They believe this is due to your illness and the negative effects of positive pressure ventilation, so they administer more IV fluid. Only after an hour do you regain the ability to breathe or move. You start to over-breathe the ventilator and set off alarms. You reach for your endotracheal tube and luckily a nurse stops you from pulling it. Only now are you given sedation and fall back into unawareness.
Sedation and analgesia of intubated patients in the emergency department is historically poor. In my experience, this is due to several factors:
- A misunderstanding of paralytic medications
Neuromuscular blockers do not provide any sedation or pain relief.
I’m going to repeat that: neuromuscular blockers DO NOT provide any sedation-or analgesia.
I could give you 70 mg of rocuronium, 7 mg of vecuronium, or 150 mg of succinylcholine right now and, after about 30-60 seconds, you would become unable to move, breathe, or even blink, but would remain completely conscious. This means that any patient receiving a long or short acting paralytic MUST receive sedation as well, at least for as long as the duration of that paralytic.
- A misunderstanding of the duration of induction agents
After intubation in the emergency department, it is typical for providers to let their guard down, believing the hard work is done. This often looks like people leaving the room or becoming focused on other tasks. This is a huge problem for many reasons, as patients are at there most vulnerable during AND immediately after intubation. One of the problems with this is that post-intubation analgesia and sedation is not made a priority. The most common induction agent used in the ED is etomidate. This drug provides adequate sedation for maybe 3-5 minutes. Unless you have prepared post-intubation sedation drugs prior to intubation, it is likely there will be a gap in sedation. If the patient has received a long-acting neuromuscular blocker (most commonly rocuronium), this means the patient may have a period of awareness, in which paralysis continues despite a return to consciousness. Even succinylcholine, which has a shorter duration, can still last up to 10 minutes, depending on the patient. So even then, the patient could have a period of awareness.
The best way to avoid this is to ensure post-intubation sedation is prepared PRIOR to intubation in EVERY patient, regardless of induction agent.
- A fear of sedating critically ill or hemodynamically tenuous patients
The sedatives frequently used in the emergency setting are known to cause decreases in blood pressure (e.g propofol, midazolam, lorazepam). In very ill patients, this can cause problems. However, there is almost never a time where a patient is so hemodynamically compromised that they cannot receive any analgesia or sedation. This is especially true with modern post-intubation analgosedation practices. This includes the idea of providing analgesia first, typically fentanyl, which can reduce the amount of sedative required and likely result in improve hemodynamics over sedatives alone. Additionally, ketamine is an effective post-intubation agent and is more likely to maintain hemodynamic parameters than other agents. It has the added benefit of providing analgesia in addition to sedation (dissociation). Also, It is acceptable to initiate or increase vasopressors if necessary to support blood pressure. Hemodynamic compromise is not an adequate excuse for poor sedation.
This is a problem that may be more prevalent in the prehospital setting simply due to the regulation of controlled substances and more strict documentation requirements, but can certainly be a factor in the emergency department as well. Using controlled substances often requires additional paperwork, time, and effort which a busy emergency provider may not want to deal with. This is clearly unacceptable but is a real occurrence.
Post-intubation best practices:
-Prepare all necessary agents prior to intubation
-Use an analgesia first strategy, typically with fentanyl or ketamine (at analgesic or dissociative doses). Hydromorphone can also be used for this purpose.
-Monitor for signs of awareness – increased HR, BP, or ETCO2 can be seen even in paralyzed patients
-Consider ketamine as a sole agent for post-intubation sedation in the emergency setting in infusion and/or bolus form. It provides rapid, reliable sedation (dissociation) with a longer duration of action than traditional agents. It is also more hemodynamically neutral than other drugs (and potentially sympathomimetic) making it the agent of choice in tenuous patients.
-Use vasopressors as necessary to support post-intubation hemodynamics and to facilitate adequate analgosedation.
For a modern approach to post-intubation sedation and analgesia see this article:
Co-authored by Michael Perlmutter
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- Weingart S. EMCrit Podcast 21—A Bad Sedation Package Leaves Your Patient Trapped in a Nightmare. EMCrit RACC, https://emcrit.org/racc/post-intubation-sedation/.
- Scott Weingart. Podcast 115 – A New Paradigm for Post-Intubation Pain, Agitation, and Delirium (PAD). EMCrit Blog. Published on January 13, 2014.
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