Prevention of hypothermia during hip surgery: effect of passive compared with active skin surface warming

Abstract

We have measured aural canal (core) and skin temperatures, and body heat content in 45 patients undergoing elective hip arthroplasty. They received general anaesthesia which included thiopentone, vecuronium and enflurane and nitrous oxide in oxygen. Patients were allocated randomly to three groups: group 1, control (n = 15), received no intraoperative warming device; group 2 had passive skin surface warming (metallized plastic sheet, Thermolite (n = 15); and group 3 had active skin surface warming (forced heated air, Bair-Hugger) (n = 15). Duration of surgery, fluid administration and the temperature and relative humidity of the operating theatre were similar for the three groups. Core temperature and mean body heat content decreased significantly during surgery in groups 1 and 2 (aural canal temperature 1.5 and 1.0 degrees C, and mean body heat content 287 and 189 kJ, respectively), while in group 3 these variables remained near preoperative values (P = 0.001). Mean skin and hand temperatures decreased in the control group, increased in the active warming group and were unchanged in the passive warming group (P < 0.005), indicating that the forced heated air system was very efficient in providing thermal homeostasis during surgery, while the metallized plastic sheet was able to insulate the skin only from radiant and convective heat losses, without attenuating the reduction in core temperature.

Peri‐operative warming devices: performance and clinical application

“…This is the most commonly tested body warming modality and is unsurprisingly associated with significantly higher postoperative core temperatures when compared with patient control groups where no warming was used [41][42][43]. The dual benefit of transferring heat to the body and reducing heat losses [44] from the skin under the air warmer accounts for this finding.…”

Randomized non-inferiority trial of the vitalHEAT™ Temperature Management System vs the Bair Hugger® warmer during total knee arthroplasty

“…7 Core temperatures and body heat content decreased significantly in the reflective insulation and control groups, while the Bair Hugger Ò patients maintained thermal homeostasis. In the Bennett study, the patient population and use of the Bair Hugger Ò were similar to ours in that general anesthesia was administered, an upper body Bair Hugger Ò was used (set at 43°C), ambient temperature fluids were infused, and the patients were placed in the supine position.…”

Diagnosis, prevention and treatment of accidental and perioperative hypothermia

“…The addition of more layers or the use of warmed blankets does not, unfortunately, increase the benefit proportionally [106] . Reflective insulation materials are not more efficient compared to standard drapes [4,6,13,17,92,108] . The recent improvements made in clothing for outdoor activities indicate that technological advances in drapes and blankets for hospital use must be possible [15] .…”

“…Without active perioperative warming, the majority of surgical patients will become at least slightly hypothermic (core temperature < 36 ° C) [4] . Torossian et al reported a survey on thermomanagement in 316 European hospitals that on a certain day during 8083 surgical procedures, only in 19 % of the patients was body temperature monitored, and only 38 % were actively warmed [118] .…”