Effect of therapeutic hypothermia on superficial surgical site infection and postoperative pain in urgent abdominal surgery.

Background: Although therapeutic hypothermia has been shown to be effective on surgical site infection and postoperative pain in patients undergoing elective surgery, its exact effect on emergency laparotomy remains unclear. In this study, we aimed to investigate the effect of therapeutic hypothermia on superficial surgical site infection and postoperative pain in patients undergoing urgent open abdominal surgery.

Methods: The study included 100 patients who underwent emergency open abdominal surgery from 01/01/2016 to 01/01/2017. The patients were randomly divided into two groups: therapeutic hypothermia, group I underwent cold therapy with local sterile frozen ice compress; and control group II, underwent conventional sterile compress. Age, gender, primary pathology diagnosis, size of incision, wound type and size, and duration of surgery were compared between the groups. Visual analog scale scores were determined every 3 hours, and the requirement for analgesics was assessed for each patient within 48 hours postoperatively. Both before and after 5 days of laparotomy, c-reactive protein (CRP), white blood cell count (WBC), albumin, serum total antioxidant status, and total oxidant status levels were measured, and oxidative stress index was calculated for each patient. The rates of superficial surgical site infection were compared between both groups.

Results: The two groups were similar in terms of age, gender, primary pathology diagnosis, size of incision, wound type and size, and duration of surgery (p>0.05). Although no significant difference was found between the groups with regards to visual analog scale scores (p>0.05), requirement for analgesics was lower in the group I compared to that in the control group (p<0.05). No significant difference was found between the groups in terms of preoperative WBC, albumin, CRP, serum total antioxidant status, total oxidant status, and oxidative stress index (OSI) levels (p>0.05). At postoperative day 5, serum total antioxidant status level was significantly higher, and OSI level was significantly lower in the group I compared to the respective levels in the control group (p<0.05). Moreover, the superficial surgical site infection rate was significantly lower in the group I (p<0.05).

Conclusion: In patients undergoing urgent open abdominal surgery, therapeutic hypothermia led to lower requirement for analgesics and lower superficial surgical site infection rates in the early postoperative period. We consider that therapeutic hypothermia exerts this effect by elevating the serum total antioxidant status level, and decreasing the effects of inflammatory mediators and OSI.