Background and Goal of Study
Unintentional hypothermia is common during surgical procedures, mostly due to impaired thermoregulatory control induced by anaesthesia. The goal of temperature monitoring is to maintain appropriate temperature during all anaesthetic procedures. Nevertheless, in short procedures with minimal surgical exposure, temperature monitoring is often neglected. The aim of this study was to evaluate the temperature variation (TV) in patients submitted to minor surgery procedures.

Material and Methods
After Hospital Ethics Committe approval, a prospective audit was conducted including 200 patients submitted to minor surgical procedures at a tertiary hospital, between March to July of 2015. Gender, age, American Society of Anaesthesia Physical Status (ASA), Body Mass Index (BMI), type of anaesthesia, surgery duration, use of active warming and hospital length stay were collected. Tympanic temperature was monitored using Grado® thermometer (RM205V model), on five moments: Operating Room arrival (T1), after anaesthetic induction (T2), end of surgery (T3), Post Anaesthesia Care Unit arrival (PACU) (T4) and at PACU discharge (T5). ∆T2-T1, ΔT3-T2, ∆T4-T1, ΔT5-T1 and ΔT5-T4 were calculated. Results: number, percentage, mean ± standard deviation (SD) and median (SPSS® v.22).

Results and Discussion
200 patients included (55% female); age ranging between 19 and 92 years old (median 61). ASA 1: 8%; 2: 69%; 3: 23%; 4: 1%. Mean BMI was 27,12 ± 4,23 Kg/m2. 85% were submitted to general anaesthesia (GA), surgery mean duration was 55 ± 32 minutes. 25% (n=50) were actively warmed during surgery. Mean hospital stay 3,35 ± 3,28 days.
T1: 36,24 ± 0,51 ºC; T2: 36,01 ± 0,6 ºC; T3: 35,5 ± 0,68 ºC; T4: 35,33 ± 0,65 ºC; T5: 35,65 ± 0,56 ºC.
ΔT3-T2: -0,74 ± 0,56ºC, ΔT5-T1: -0,58 ± 0,51ºC and ΔT5-T4: 0,33 ± 0,43ºC.
Patients with perioperative heat loss (HL) ≥ 0,6ºC: 17% ∆T2-T1; 46% ∆T3-T2; 73% ∆T4-T1 (33% with HL  between 0,6ºC and 1,0ºC and 40% with HL > 1,0ºC), 52% ∆T5-T1 (38% with HL  between 0,6ºC and 1,0ºC and 14% with HL > 1,0ºC). 95% with HL ≤ 0,5ºC in ∆T5-T4.

Conclusion
This prospective audit suggests that even in minor surgical procedures, with minimal surgical exposure and with a short duration, there is an important heat loss.  This prospective audit let us think about the importance of temperature monitoring and the necessity of develop and implement strategies to avoid HL in perioperative period.

Importance of temperature monitoring in minor surgical procedures - 200 patients: a prospective audit