Study objective: To evaluate and compare the efficacy and related side effects of alfentanil and remifentanil in preventing the withdrawal movement associated with rocuronium injection.
Design: Prospective, randomized, blinded, placebo-controlled clinical trial.
Setting: Operating room of a university hospital.
Patients: 115 ASA physical status I and II adult patients.
Interventions: Patients were randomly allocated to one of three study groups. Group C received saline, Group A received alfentanil 10 microg/kg, and Group R received remifentanil one microg/kg, each in a volume of three mL. Treatments were injected over 30 seconds, followed by thiopental sodium. At 90 seconds after the start of the study drug injection, rocuronium 0.6 mg/kg was injected over 10 seconds.
Measurements: Cough, breathholding, and thoracic muscle rigidity were observed while injecting the study drug. Each patient's response to the rocuronium injection was graded on a 4-point scale in a blinded manner.
Main results: During injection of the study drug, Group R showed a significantly higher frequency of cough than Group A (24% vs. 2%; P < 0.05). One Group R patient presented with apnea. Frequency of withdrawal movement in Groups A and R were significantly lower than that in Group C (6% and 0% vs. 63%; P < 0.0001) but there was no significant difference between the two groups.
Conclusion: When administered 90 seconds before rocuronium injection, alfentanil showed a comparable effect to that of remifentanil in attenuating rocuronium-associated withdrawal movement, and a lower frequency of side effects such as cough.