Background and Goal of Study: Early postoperative hypothermia is a preventable complication with adverse consequences on morbidity and patient well-being, particularly in elderly. Our study aimed to determine the incidence of early postoperative hypothermia and its related clinical outcome in elderly patients. 

Materials and Methods: We conducted an observational prospective study after approval by the Institutional ethics committee. Patients aged>60 years, submitted to elective surgery and admitted to Post Anaesthetic Care Unit (PACU) were included. Clinical Frailty Scale was used to evaluate vulnerability and frailty was defined as a score ≥5. The score of the World Health Organization Disability Assessment Schedule (WHODAS) was used to assess disability. The Physiological and Operative Severity Score for the Enumeration of Mortality and Morbidity (POSSUM) was calculated. At PACU admission, patients with an auricular temperature <35ºC were considered to be hypothermic patients (HPP). Richmond Agitation Sedation Scale (RASS) was used at PACU admission (T0) and 15 minutes later (T15). Quality of Recovery was evaluated using Quality of Recovery-15 (QoR-15) 24 hours (T24) after surgery. The Mann-Whitney test, Chi-square or Fisher’s exact test were used for comparison.

Results and Discussion: Of a total of 235 patients, 26% were HPP at PACU admission. HPP had lower scores of RASS at T0 (p=0.044) but at T15 these scores were similar. Hypothermia incidence was related to type of anesthesia (62% for general anesthesia vs. 22% for combined general and regional vs. 17% for regional anesthesia, p=0.030) and HPP had a median longer time of anesthesia (141 vs.125 minutes, p=0.030). These patients were less frequently frail (13% vs. 26%, p= 0.048) and had lower median global WHODAS scores (8.3 vs 14.6, p=0.018). According to POSSUM, HPP had higher risk of morbidity (43% vs 36%, p=0.016) and higher risk of mortality (11% vs. 10%, p=0.023). These patients developed more frequently cardiac events (5% vs. 0%, p=0.003). At T24 HPP median total scores for QoR-15 were similar.  

Conclusions: The incidence of hypothermia was considerably high and was less frequent among frailty patients and in patients with problems in physical functioning and quality of life. Patients with hypothermia were at higher risk of mortality and morbidity and had more frequently cardiac events but their quality of recovery was similar.

08 / Postoperative hypothermia and clinical outcome in elderly patients