NEW YORK (Reuters Health) – Intraoperative hypothermia to less than 35 C more than doubles the risk of surgical site infections after trauma laparotomy, according to a report in the Annals of Surgery online March 1.
“Our results suggest that intraoperative normothermia should be strictly maintained in patients undergoing operative trauma procedures,” conclude Dr. Mark J. Seamon, at Cooper University Hospital in Camden, New Jersey, and colleagues.
They note that intraoperative normothermia is an established quality measure in colorectal surgery, but its effects on surgical site infection (SSI) rates after trauma laparotomy have not been studied. To investigate this point, the team reviewed outcomes in 524 patients requiring urgent trauma laparotomy at a level 1 trauma center and who survived at least 4 days.
In this cohort, the mean intraoperative temperature nadir was 35.2 C, and 30.5% had measurements below 35 C. Rates of SSI within 30 days were 46.3% in patients with an intraoperative temperature nadir <35 C compared 30.5% in those with temperature nadirs of at least 35 C, the report shows.
After controlling for confounding factors, the authors found that every degree below 35 C more than doubled the risk of SSI (odds ratio 2.21; p=0.007).
They explain that hypothermia triggers cutaneous vasoconstriction, which leads to relative wound hypoxia – and this in turn affects host immune defense mechanisms.
“To our knowledge, this report is the first to implicate intraoperative hypothermia in the development of SSI after trauma laparotomy,” Dr. Seamon and colleagues note, although intraoperative warming has been shown to decrease SSI risk after head and neck, cardiothoracic, and general surgery, as well as cholecystectomy and open abdominal surgery.“Our data suggest that aggressive intraoperative warming measures will help prevent SSI and improve outcomes after trauma laparotomy,” they advise.