Forced air warming to maintain normoTHERMIa during SEDation in the cardiac catheterization laboratory: protocol for the THERMISED pilot randomized controlled trial

Comparison of two forced-air warming devices during foot and ankle surgery: a randomised controlled trial

Inadvertent perioperative hypothermia is a frequent problem associated with surgical patients which can have significant consequences during surgery and in the immediate postoperative period. We compared 35 randomised patients using over vs. under body forced air heating. There were no statistically significant differences between some demographic and surgical parameters such as: age, weight, height, body mass index, length of anaesthesia and operation. Statistically significant differences were found between the patient's admission to the operating room and 30 minutes and the end of the procedure on the under body patients group. This study analyses a uniform population of patients (Foot and Ankle Surgery) previously not studied and supports the use of under body blankets.

Cost-effectiveness of forced air warming during sedation in the cardiac catheterisation laboratory

AIM

The aim of this study was to determine the cost-effectiveness of forced air warming (FAW) during sedation in a cardiac catheterisation laboratory.

BACKGROUND

Forced air warming improves thermal comfort in comparison with standard care. It is not known whether the extra costs required for FAW are good value.

DESIGN

Cost-effectiveness analysis alongside a randomized controlled trial conducted in 2016-2017.

METHODS

A cost-effectiveness analysis was undertaken using Monte Carlo simulations from input distributions to estimate costs and effects associated with using FAW to reduce risk of thermal discomfort for patients receiving sedation in a cardiac catheterisation laboratory. A range of willingness to pay threshold values were tested with results plotted on a cost-effectiveness acceptability curve. Costs were calculated in Australian currency ($AUD).

RESULTS

Estimated total costs were $5.21 (SD 3.26) higher per patient for FAW in comparison to standard care. Estimated probability of success (rating of thermal comfort) was 0.16 (0.06) higher for FAW. Forced air warming becomes more likely to result in a net benefit than standard care at a willingness to pay threshold of $34.

CONCLUSION

Forced air warming could be considered cost-effective for procedures performed with sedation in a cardiac catheterisation laboratory if the extra cost of an incremental gain in thermal comfort is less than the decision maker's willingness to pay for it. Therefore, those responsible for decision-making regarding use of FAW in the cardiac catheterisation laboratory can use results of our model to decide if it represents good value for their organisation.

Forced air warming during sedation in the cardiac catheterisation laboratory: a randomised controlled trial

OBJECTIVE

Forced air warming (FAW) during general anaesthesia is a safe and effective intervention used to reduce hypothermia. The objective of this study was to determine if FAW reduces hypothermia when used for procedures performed with sedation in the cardiac catheterisation laboratory.

METHODS

A parallel-group randomised controlled trial was conducted. Adults receiving sedation in a cardiac catheterisation laboratory at two sites were randomised to receive FAW or usual care, which involved passive warming with heated cotton blankets. Hypothermia, defined as a temperature less than 36°C measured with a sublingual digital thermometer after procedures, was the primary outcome. Other outcomes were postprocedure temperature, shivering, thermal comfort and major complications.

RESULTS

A total of 140 participants were randomised. Fewer participants who received FAW were hypothermic (39/70, 56% vs 48/69, 70%, difference 14%; adjusted RR 0.75, 95% CI=0.60 to 0.94), and body temperature was 0.3°C higher (95% CI=0.1 to 0.5, p=0.004). FAW increased thermal comfort (63/70, 90% vs51/69, 74% difference 16%, RR 1.21, 95% CI=1.04 to 1.42). The incidence of shivering was similar (3/69, 4% vs 0/71 0%, difference 4%, 95% CI=-1.1 to 9.8). One patient in the control group required reintervention for bleeding. No other major complications occurred.

CONCLUSION

FAW reduced hypothermia and improved thermal comfort. The difference in temperature between groups was modest and less than that observed in previous studies where use of FAW decreased risk of surgical complications. Therefore, it should not be considered clinically significant.

TRIAL REGISTRATION NUMBER

ACTRN12616000013460.