A multicentre, randomised, open-label, controlled trial evaluating equivalence of inhalational and intravenous anaesthesia during elective craniotomy

CONTEXT: A clear preference for intravenous or inhalational anaesthesia has not been established for craniotomy in patients without signs of cerebral hypertension. OBJECTIVES: The NeuroMorfeo trial was designed to test equivalence of inhalational and intravenous anaesthesia maintenance techniques in the postoperative recovery of patients undergoing elective supratentorial surgery. DESIGN: This trial is a multicentre, randomised, open-label, equivalence design. A balanced stratified randomisation scheme was maintained using a centralised randomisation service. Equivalence was tested using the two one-sided tests procedure. SETTING: Fourteen Italian neuroanaesthesia centres participated in the study from December 2007 to March 2009. PATIENTS: Adults, 18 to 75 years old, scheduled for elective supratentorial intracranial surgery under general anaesthesia were eligible for enrolment if they had a normal preoperative level of consciousness and no clinical signs of intracranial hypertension. INTERVENTIONS: Patients were randomised to one of three anaesthesia maintenance protocols to determine if sevoflurane-remifentanil or sevoflurane-fentanyl were equivalent to propofol-remifentanil. MAIN OUTCOME MEASURES: The primary outcome was the time to achieve an Aldrete postanaesthesia score of at least 9 after tracheal extubation. Secondary endpoints included haemodynamic parameters, quality of the surgical field, perioperative neuroendocrine stress responses and routine postoperative assessments. RESULTS: Four hundred and eleven patients [51% men, mean age 54.8 (SD 13.3) years] were enrolled. Primary outcome data were available for 380. Median (interquartiles) times to reach an Aldrete score of at least 9 were 3.48 (2.02 to 7.56), 3.25 (1.21 to 6.45) and 3.32 min (1.40 to 8.33) for sevoflurane-fentanyl, sevoflurane-remifentanil and propofol-remifentanil anaesthesia respectively, which confirmed equivalence using the two one-sided tests approach. Between-treatment differences in haemodynamic variables were small and not clinically relevant. Urinary catecholamine and cortisol responses had significantly lower activation with propofol-remifentanil. Postoperative pain and analgesic requirements were significantly higher in the remifentanil groups. CONCLUSION: Equivalence was shown for inhalational and intravenous maintenance anaesthesia in times to reach an Aldrete score of at least 9 after tracheal extubation. Haemodynamic variables, the quality of surgical field and postoperative assessments were also similar. Perioperative endocrine stress responses were significantly blunted with propofol-remifentanil and higher analgesic requirements were recorded in the remifentanil groups. Trial registration: Eudract 2007-005279-32