As anesthesiologists, endotracheal intubation is a procedure we routinely do in the operating room but also emergently in patients who have cardiopulmonary arrest, depressed consciousness, impending hypoxemic and/or hypercarbic respiratory failure, or profound respiratory weakness.
If a patient is in true cardiopulmonary arrest (ie, during a “code blue”), I don’t push any drugs and proceed to intubate the trachea. In the operating room, I typically perform a controlled induction with careful preoxygenation and positioning (maximizing a patient’s functional residual oxygenation with 100% O2) before administering analgesics (typically fentanyl), hypnotics (propofol, etomidate), and paralytics (succinylcholine, rocuronium, cisatracurium, vecuronium). Once the patient is unconscious, I mask ventilate until the paralytic has fully kicked in. Then I intubate. 🙂
I’ve previously written about how I approach endotracheal intubation but wanted to discuss a particular variant – the rapid sequence intubation (RSI). This style of intubation is performed whenever patients are at a higher risk for aspiration (not adequately NPO, increased intragastric pressure, decreased gastric motility, etc.) or when securing the airway ASAP is of paramount importance (trauma, depressed consciousness). Typically, all emergent floor intubations are done with RSIs as we often know very little about these patients and assume full stomachs.
Before an RSI, I quickly gather some of the patient’s history and coordinate my plan with the nurses and respiratory therapist (RT). I’ll ensure I have all of my supplies (endotracheal tube, suction, medications, laryngoscope, CO2 detector for placement confirmation, etc.) After a brief preoxygenation, I typically use etomidate and succinylcholine, but I’ve used ketamine, propofol, and high dose rocuronium under certain circumstances to induce the anesthetic.
I always have syringes of norepinephrine, epinephrine, calcium, esmolol, and nitroglycerine readily available as well. In fact, I’ll routinely push 250 mg of calcium or 10 mcg of norepinephrine prior to induction in very unstable patients with significant cardiovascular comorbidities. These patients can usually tolerate brief periods of hypertension, but hypotension could provoke a downward spiral of myocardial ischemia and cardiogenic shock.
Once the patient is unconscious, mask ventilation is not performed. This is a key difference between the RSI and conventional intubation. Foregoing mask ventilation after unconsciousness avoids inadvertent insufflation of the stomach which could promote regurgitation and aspiration. I’ll sometimes have an assistant hold cricoid pressure after induction, but if this impairs my laryngoscopy, I’ll have them quickly release the pressure. Once the patient is intubated, I confirm endotracheal tube placement and manage the resulting hemodynamics accordingly. On average, I’d say from the time the drugs are pushed till the endotracheal tube cuff is inflated in the trachea, less than 30 seconds have passed.