Open abdominal surgery increases intraoperative oxidative stress: can it be prevented?

Background: The involvement of reactive oxygen species early in the development of surgical stress and injury is highly suspected but has not been confirmed. Medical approaches to manage this type of oxidative stress are unknown.

Methods: We measured levels of blood hydroperoxides as an index of oxidative injury of cellular components, as well as plasma ferric-reducing ability as an index of total antioxidant potential, during sigmoidectomy under four conditions: open sigmoidectomy with sevoflurane anesthesia, laparoscopic sigmoidectomy with sevoflurane anesthesia, open sigmoidectomy with propofol anesthesia, and laparoscopic sigmoidectomy with propofol anesthesia.

Results: Ferric-reducing ability decreased significantly during surgery for the open sigmoidectomy with sevoflurane anesthesia, by 387 +/- 153 mmol/L, though the hydroperoxides level did not change, showing that oxidative stress increases in surgical patients. However, its toxicity may not be high enough to injure cellular components, since hydroperoxides, which are typical oxidized products of cellular components, did not increase. There were no changes in the hydroperoxides level or the ferric-reducing ability for the laparoscopic sigmoidectomy with sevoflurane anesthesia, indicating that this procedure does not increase surgical oxidative stress. Only hydroperoxides decreased significantly at the end of surgery for the open sigmoidectomy with propofol anesthesia and laparoscopic sigmoidectomy with propofol anesthesia, by 120 +/- 73 and 144 +/- 107 UCarr (1 UCarr corresponds to 0.8 mg/L H(2)O(2)), respectively.

Conclusions: It seems certain that open abdominal surgery of the intestinal tract increases intraoperative oxidative stress. A laparoscopic procedure was not associated with oxidative stress, and propofol anesthesia reduced it by apparently functioning as an antioxidant.