Perioperative hypothermia (<36 ºC core temperature) can be favored by various factors. It is essential to know the methods of prevention and treatment of hypothermia to avoid its potential consequences. We present the case of a 75-year-old woman who needed urgent surgery for acute arterial ischemia of the right lower extremity and in whom a generalized body coldness stood out from the initial examination. After intubation, etCO2 values of 18mmHg are detected and a temperature of 29.9 ºC is monitored. Due to the use of active warming devices during the intraoperative period, her temperature increased to 33 ºC upon admission to the ICU.