Hot Climate and Perioperative Outcome in Trauma Patients

Extreme hot climatic conditions constitute a major public health threat. Recent studies have shown higher rate of perioperative complications during hot weather. Although a lot of researches have been carried out to evaluate effect of hot climatic conditions and its correlation with other medical conditions, but very little has been studied in trauma patients.

To evaluate the impact of hot climatic conditions on perioperative morbidity in trauma patients.

We enrolled 100 trauma patients scheduled for surgery after approval by the Hospital and University Ethical Committee. Patients were grouped as Control Group (C) when outdoor temperature ranged in comfortable zone i.e., 20-29(0)C and Study Group (S) when outdoor temperature ranged 40(0)C or more. Patients living in regular air conditioned atmosphere (more than 18 hours per day) and with co-morbid conditions or on drugs interfering with temperature regulation were excluded. Student's t-test, z-test and chi-square tests were used for statistical analysis.

Both groups were comparable in terms of demographics, age (control group C=38.2±12.93 years and in group S= 40.14 ± 15.98 years), sex, socioeconomic status and type of surgery. Mean Trauma Index Score (TIS) were 6.20±1.56 and 5.80±1.31 respectively. All patients were of low risk as per Shoe Maker's risk criteria. Post Anaesthesia Care Unit (PACU) stay was similar. Mean duration of hospital stay was 12.16 ± 8.50 days in group C and 10.98 ± 6.90 days in group S (p-value 0.21). 20% patients in group C whereas 54% in group S had complications (p= 0.009). There was a higher incidence of infections as well as respiratory distress in group S. On multiple logistic regression analysis peak environmental temperature was found to be the single independent risk factor for predicting perioperative morbidity.

High ambient temperature adversely affects the outcome of surgery even in low risk young trauma patients belonging to American Society of Anaesthesia (ASA) physical status I and II categories. So we opine that it may be probably helpful to either postpone non-emergency surgery till fair adaptation is achieved in air conditioned environment of hospital or be cautious for complications to reduce the heat related perioperative morbidity in days of heat waves.