Napanont Kiatmongkolkul, MD¹, Tanat Chotijarumaneewong, MD¹

Background: Rapid-sequence intubation (RSI) involves administering an intravenous anesthetic agent and a rapid-onset neuromuscular blocking agent (NMBA) to facilitate rapid and secure intubation. The currently recommended NMBAs for RSI are succinylcholine or rocuronium.

Objective: To explore whether the alternative high-dose cisatracurium, which is eight times the 95% effective dose (8ED95), is comparable to standard-dose rocuronium (4ED95) for providing excellent intubating conditions during RSI.

Material and Methods: A double-blind randomized controlled trial study was designed to include 124 participants. All patients were randomly divided into two groups of 62 patients each, with one group receiving 0.4 mg/kg cisatracurium (CIS group) and the other receiving 1.2 mg/kg rocuronium (ROC group). Intubating conditions were assessed 90 seconds after induction, which was defined as excellent, characterized by easy laryngoscopy, wide-open vocal cords, and no coughing or limb movement. The primary outcome was the proportion of excellent intubating conditions, with a predefined non-inferiority (NI) margin of –10%. Secondary outcomes included anesthesiologist’s satisfaction, train-of-four (TOF) count at 90 seconds, TOF count at successful intubation, time to TOF count of 0, time to TOF count of 1, hemodynamic parameters, and number of adverse events requiring treatment.

Results: Excellent intubating conditions were found in 91.94% (57 out of 62) and 95.16% (59 out of 62) of patients in the CIS and ROC groups, respectively. The risk ratio of non-excellent intubating conditions in the CIS group was 1.725 compared with the ROC group, without statistical significance (95% CI 0.394 to 7.555, p=0.469). However, the intervention could not demonstrate a NI margin of less than –10% to standard-dose rocuronium (p=0.08). The CIS group showed a significantly slower onset time than the ROC group, with a median time to TOF 0 of 215.5 seconds (IQR 183 to 270) versus 167 seconds (IQR 110 to 220) (p=0.024). The other secondary outcomes, including the anesthesiologist’s satisfaction, showed no significant differences.

Conclusion: High-dose cisatracurium did not establish NI to standard-dose rocuronium for excellent intubating conditions during RSI at 90 seconds. Although clinically acceptable conditions were observed, the slower onset time of cisatracurium should be considered when rapid airway control is mandatory.

Trial registration: Thai Clinical Trials Registry, TCTR20210824007

Received 2 October 2025 | Revised 17 January 2026 | Accepted 22 January 2026

DOI: 10.35755/jmedassocthai.2026.3.03614