The inspiration for this post comes from seeing a variety of intubation methods used during my EM rotations. The first part is a basic explanation of intubating. The part to follow explores changes that can be made depending on the circumstances.
Basically, rapid sequence intubation consists of three parts: pretreatment, induction and paralysis. (The crashing patient who’s unconscious and apneic receives BVM and intubation w/out pretreatment, induction or paralysis)
Oversimplifying the process helps to keep things straight inside a beginner’s head, so we’ll start simple. In reality, there’s the 9 P’s to think about (Plan, Preparation, Protect C spine, Positioning, Preoxygenation, Pretreatment, Paralysis/Induction, Placement w/ proof, and Postintubation care). There will be many different changes in medications, equipment choices etc depending on the patient. But, that all comes later. For now, let’s start with an overview of the three parts of RSI: Pretreatment, induction and paralysis.
Part I: Pretreatment LOAD the patient
Use of specific medications to reduce the sympathetic response to laryngoscopy, large changes in BP or spikes in ICP.
Use the mnemonic LOAD to remember what medications to load the pt on when starting pretreatment.
Lidocaine –> Reduces any increase in MAP, HR or ICP. Use for pt w/ suspected intracranial process or increased ICP. Also, use in pt where increased BP is detrimental (i.e. AAA).
Opioid analgesic –> Reduces any increase in physiologic sympathetic tone. However, there’s no conclusive evidence of the effectiveness of opioids in RSI.
Atropine –> Opposite role than the aforementioned drugs. Decreases any parasympathetic effects on the heart. Laryngoscopy and the use of succinylcholine have potential for slowing the heart. The effect is caused by direct stimulation of the larynx or by succinylcholine’s slowing effect on the heart.
Defasiculating agent –> A small dose of a paralytic to reduce any fasciculations when succinylcholine is eventually given.
Part II: Induction agents Induce analgesia, sedation, and amnesia
Etomidate –> Hemodynamically stable
Ketamine –> Hemodynamically stable
Propofol –> Anti-epileptic properties but hemodynamically unstable
Midazolam –> Anti-epileptic properties and rapid onset but can be hemodynamically unstable
Part III: Paralytics No more moving
Succinylcholine –> Depolarizing NMJ blocker. Rapid onset and short duration.
Rocuronium –> Nondepolarizing NMJ blocker. Longer onset and longer duration.