A quality improvement project incorporating preoperative warming to prevent perioperative hypothermia in major burns

Patients with extensive burn injuries are susceptible to a host of accompanying adverse effects should they develop perioperative hypothermia, which occurs in up to ¼ of all major burn cases. This quality improvement project aimed to reduce the incidence of perioperative hypothermia to below 10% of cases in patients with major burn (Total Body Surface Area [TBSA] >15%), within a one year period.

A baseline diagnostic phase was undertaken to provide a greater understanding of the incidence, natural history and risk factors of perioperative hypothermia. We also reviewed and reinforced intraoperative measures in current use, including preemptive adjustment of the ambient temperature, underbody warming mattress use, warming blanket application over areas not operated, regular temperature monitoring, and discussion at the WHO surgical checklist. Preoperative forced air warming with a 'Bair Hugger'™ was identified as a sound change initiative, a strategy applied to good effect in other surgical settings. The primary outcome measure was the percentage of cases of perioperative hypothermia (<36°C), utilizing a time series design for the period between 1 November 2016 and 31 October 2017.

53 patients with burn greater than 15% TBSA were admitted over the one year period. Of these, 40 patients required 127 operative procedures. Their mean age was 48.23 years, their mean TBSA was 27.65% (range 15-75%), and their mean length of hospital stay was 31.2 days. After the introduction of pre-warming, the proportion of cases of inadvertent hypothermia reduced to 13.77% (n=14/102), with special cause variation, from 24% (n=6/25) in the baseline data collection period. The final temperature correlated with the lowest temperature recorded in only 32% of cases. Based on stakeholder feedback and consensus from the literature, an algorithm was developed which forms the basis for a medical directive for preoperative warming for eligible patients. No significant balancing measures were identified, nor any undue costs incurred.

The inevitable drop in temperature is ameliorated by sound perioperative practices, rather than just intraoperative ones. This initiative demonstrated the potential benefits of, and motivates for, the broad application of preoperative warming in the context of major acute burn surgery. Further investigations include PDSA cycles to determine whether the duration or degree of intraoperative hypothermia is more virulent. To consolidate the pre-warming initiative, we have introduced a standard order within our admission order sets to include preoperative warming for all eligible patients.