Rapid sequence induction

Editor-in-Chief: Santosh Patel M.D., FRCA [mailto:santosh.patel@pat.nhs.uk]

Overview
Rapid sequence induction (RSI, also referred to as rapid sequence intubation when performed in an Emergency Department or pre-hospital setting) is an advanced medical protocol which permits the intubation of conscious patients who require advanced airway support. Having evolved from procedures used to "induce" a coma-state in preparation for surgery, RSI is now often used in emergency settings also.

RSI involves the use of a sedative/hypnotic medication to relax the patient followed by administration of a rapid-acting neuromuscular blocker (a paralytic) to disable the patient's involuntary reflex to fight the intubation. Sedatives typically used include thiopental, propofol, versed, or etomidate. Neuromuscular-blocking drugs typically used include succinylcholine or rocuronium. The combination enables the insertion of an endotracheal tube to ventilate patients requiring this type of advanced airway measure. Often, lidocaine is given as well if increased intracranial pressure is suspected (although there is controversy about effectiveness) and atropine is given in patients less than 2 years old to block reflex bradycardia. Sometimes fentanyl may also be used to sedate and block any pain response.

This procedure can be performed by paramedics in certain settings, especially aero-medical paramedics.

A similar procedure known as "pharmacologically assisted intubation" utilizes the sedative and hypnotic medications without the use of paralytics. This procedure is highly controversial and is usually performed where full RSI procedures are not legally allowed. RSI is the preferred procedure because it maximizes the chance of a successful intubation and reduces the chance of developing harmful increased intracranial pressure or other injuries during intubation.