Objective: To investigate the relationship between shivering symptom and core-peripheral temperature differences of postoperative patients admitted to post-anesthesia care unit (PACU) and evaluate factors related to postoperative shivering.
Material and Method: This is a prospective case control study which observed postoperative adult patient, ASA physical class I-III with the operative period of 1 to 4 hours who were admitted to PACU. Core (tympanic membrane) and peripheral (forehead and dorsum of hand) temperature was measured at 0, 15, 30, 45 and 60 minutes PACU admission. Shivering symptom was observed at the same time points of temperature measurement and classified by severity of shivering into grade 0 to 4.
Results: Patients with shivering had significantly less core-forehead temperature differences compared with patients without shivering but the core-dorsum of hand temperature differences were similar in both groups. In one hundred patients in the shivering group, 90% of the patients had shivering when immediately admitted to PACU and there were only 26% of patients having the symptom at 60 minutes. Factors related to shivering symptom were vascular surgery (adjusted OR 16.40 (95% CI 1.37 to 195.68), p = 0.03) and abdominal surgery (adjusted OR 4.38 (95% CI 1.06 to 18.09), p = 0.04).
Conclusion: The core-forehead temperature difference was related with shivering symptom in PACU while the core-dorsum of hand difference has no relationship. Types of surgery including vascular surgery and abdominal surgery were identified as factors related to shivering symptom.

Keywords: Shivering, Temperature Differences, Post-anesthetic care unit