Prevention of Perioperative Hypothermia in Transurethral Resection Under Spinal Anaesthesia

Perioperative hypothermia is one of the most common anaesthetic complications, increasing the morbidity/mortality of our patients. Active prewarming with hot forced-air devices has demonstrated to be the most effective tool to prevent hypothermia, but its use is only recommended in long-term surgeries and the optimal prewarming duration has not been elucidated. Both spinal anaesthesia associated to the irrigation with liquids at low temperature instilled during transurethral resection (TUR) cause a decrease in the core temperature of the patient. This is a clinical trial comparing different time periods of prewarming in patients submitted to undergo elective transurethral resection. Our aim is to assess the effect of different time-periods of prewarming on preventing perioperative hypothermia during TUR with spinal anaesthesia. Investigators will compare different time periods: 0 minutes (control group), 15 minutes, 30 minutes and 45 minutes. 200 patients are going to be included in this study (50 patients in each group). Measurement of temperature will be performed using a tympanic thermometer and zero-heat-flux temperature sensor. Patients will be followed throughout their hospital admission. Data will be recorded using a validated instrument and will be analysed using the statistics program R Core Team.