Rapid sequence induction (RSI, also incorrectly referred to as rapid sequence intubation) is an advanced medical protocol which permits the intubation of conscious patients who require advanced airway support. Having evolved from procedures used by anesthesiologists to "induce" a coma-state in preparation for surgery, RSI is now used in an emergency setting by other physicians and paramedics.

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 midazolam, thiopental, fentanyl, ketamine, etomidate and methohexital . Paralytics typically used include succinylcholine, rocuronim , vecuronium or pancuronium. The combination enables the insertion of an endotracheal tube to ventilate patients requiring this type of advanced airway measure. Typically, lidocaine is given as well if increased intracranial pressure is suspected and atropine is given in patients less than 2 years old to block reflex bradycardia.

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 reduces the chance of developing harmful increased intracranial pressure or other injuries during intubation. These procedures are only to be performed by physicians and paramedics properly trained in the techniques.