Incidence of post craniotomy shivering

Shivering is an early postoperative complication following neurosurgical procedures. Incidence of postoperative shivering (POS) following non-craniotomy surgeries varies between 20 to 60%. POS after craniotomy is considered high risk and requires preventive therapies. However, incidence of postoperative shivering following craniotomies is not reported in previous reports.
Aim: To determine the incidence of postoperative shivering following craniotomy.
In a descriptive study, 89 patients candidate for elective craniotomy were enrolled and followed for incidence of POS. Method of anesthesia were similar in all cases. Patients were covered with 3 layers of surgical drapes. Shivering was evaluated during the postoperative period by observation of shivering movements of more than 10 seconds duration. Core (nasopharynx) and skin temperature (dorsum of middle finger) were recorded. Patients’ temperature were measured prior to anesthesia and then every 2 hours during and after surgery.
Mean age was 53.4±14.6 and duration of surgery was 5.02±2.6. Incidence of post-craniotomy shivering was 15%. Trend of decrease in core and peripheral temperature was fast reduction at the early 2 hour of anesthesia, the slow decrease and then it reached a plateau phase. Core temperature at preoperative time (37.1±0.65) was significantly higher than in postoperative (34.2±0.56) (p=0.0001). Besides, mean peripheral temperature in preoperative period (37.2±0.72) was significantly higher than in postoperative period (34.6±0.65) (p=0.0001).
Incidence of post-craniotomy shivering was 15% in our patients. Although decrease in core and peripheral temperature were significant during craniotomy, however, the incidence of post-operative shivering is lower than other surgeries.