Intra-operative parameters
Intra-operative data (i.e., duration of operation, minute-by-minute temperature recordings, intravenous agents employed, intra-operation complications and ICU admission) were available for 108 patients (Table 1 ). According to these, the duration of anesthesia was significantly longer in the IOH group compared to the NIOH group (289 min and 189 min, respectively). One of the patients in the IOH group was admitted to the ICU with suspected malignant hyperthermia and his operation was stopped after 182 minutes.
There was no significant difference in temperatures at the beginning of the operations between the IOH and NIOH groups (35.9°C and 35.8°C, respectively; p = 0.639); however, statistical significance was observed for temperature at the end of the operation between the groups (38.3°C IOH and 36.7°C NIOH; p < 0.001). Peak temperature measured in the IOH group was 38.3°C, and peak temperature measured in the NIOH group was 36.9°C (p < 0.001).
A positive and significant correlation was found between body temperature and duration of surgery (p < 0.05), as well as between peak temperature during the operation and the duration of the operation (p < 0.001) (Figure 1 ). Two patients were admitted to the ICU: one due to suspected malignant hyperthermia (IOH group) and the other due to low oxygen saturation during the operation (NIOH group).
Intravenous agents used during the operation included Propofol, Perfalgan, Neostigmine, Atropine, Midazolam, Emerone, Tracium and Morphine; no differences were evident in the use of these agents between the IOH and NIOH groups.