Hypothesis: Patients undergoing laparoscopic abdominal surgery under propofol-based anesthesia have a lower incidence of delayed neurocognitive recovery than patients under sevoflurane-based anesthesia.
Methods: Patients aged 60 years or older undergoing elective major laparoscopic abdominal surgery in 4 hospitals in China were included. They were randomized to a propofol- or sevoflurane-based regimen to maintain general anesthesia. Subjects and investigators were blinded to study group assignment. Neuropsychological tests were carried out the day before and 5-7 days postop.
Results: Delayed neurocognitive recovery rates were not different between sevoflurane and propofol groups.
Strengths:
Randomized, controlled, double-blind trial
Multicenter
Standardized anesthetic regimen
Excluded additional medications that could influence cognition
Tight parameters for additional monitors (BIS, BP, Temp, End-Tidal CO2)
Controlled for depth of anesthesia (BIS 40-60)
Used multiple pre-validated neuropsychological assessments
Adjusted for repeat testing effect
Used both per-protocol and intention-to-treat for data analysis
Weaknesses:
Power only ~50%
Questionable external validity to other countries
Lack of intraoperative data
Lack of postoperative data
Key Point: Anesthetic choice between propofol and sevoflurane does not appear to affect the incidence of delayed neurocognitive recovery 5 to 7 days after laparoscopic abdominal surgery.