To determine if positive pressure pneumoperitoneum has adverse effects on autonomic nervous system function, we examined baroreflex sensitivity (BRS) during carbon dioxide pneumoperitoneum in patients undergoing laparoscopic surgery.
MethodsTwenty adult patients scheduled for laparoscopic gynecologic surgery were selected for the study. After general anesthesia was induced with sevoflurane, continuous electrocardiography and blood pressure were monitored. Spontaneous BRS was achieved using sequence method immediately before, and 5 minutes after, pneumoperitoneum. Heart rate variability (HRV) was also determined.
ResultsAfter pneumoperitoneum, BRS decreased from 12.9 ± 1.8 ms/mmHg to 8.1 ± 1.1 ms/mmHg (P < 0.05), and the power of the high frequency band decreased from 237.8 ms2/Hz to 49.6 ms2/Hz (P < 0.05).
ConclusionsCompared to recordings obtained before pneumoperitoneum, BRS was decreased during pneumoperitoneum. This may predispose patients undergoing laparoscopic surgery to hemodynamic instability in addition to pneumoperitoneum itself.