Which neuromuscular blocking agent is preferred for rapid sequence induction due to its rapid onset and short duration, despite a higher incidence of histamine release?

Explanation

## Neuromuscular Blocking Agents in Rapid Sequence Induction **Key Point:** Succinylcholine (suxamethonium) remains the gold standard NMBA for RSI due to its ultra-rapid onset (30–40 seconds) and very short duration (5–10 minutes), allowing rapid recovery of spontaneous ventilation if intubation fails. ### Comparison of NMBAs in RSI | Agent | Onset (sec) | Duration (min) | Type | Histamine Release | Ideal for RSI? | |-------|-------------|----------------|------|-------------------|----------------| | Succinylcholine | 30–40 | 5–10 | Depolarizing | Yes (+++++) | YES | | Rocuronium | 60–90 | 30–40 | Non-depolarizing | No | Alternative | | Vecuronium | 120–150 | 30–40 | Non-depolarizing | No | No | | Cisatracurium | 120–150 | 40–60 | Non-depolarizing | Minimal | No | | Pancuronium | 60–90 | 60–90 | Non-depolarizing | No | No | **High-Yield:** Succinylcholine's rapid onset and offset are unmatched. If intubation fails and ventilation becomes impossible ("cannot intubate, cannot ventilate"), succinylcholine wears off in minutes, allowing spontaneous breathing to resume — a critical safety margin. **Clinical Pearl:** Although succinylcholine causes histamine release (flushing, bronchospasm risk), this is clinically manageable with pretreatment (H1/H2 blockers in at-risk patients). The risk is outweighed by the safety advantage of rapid recovery. **Mnemonic:** **SUCK** — **S**uccinylcholine is **U**ltra-rapid for **C**ritical **K**eys (onset, offset, RSI). ### Mechanism Succinylcholine is a depolarizing agent that mimics acetylcholine, causing sustained depolarization and fasciculations followed by flaccid paralysis. Its rapid hydrolysis by plasma pseudocholinesterase ensures quick offset.