Predictive factors for post-operative drainage after partial superficial parotidectomy: a case-control study.

Objectives: This study aimed to identify the pattern of post-operative drainage following partial superficial parotidectomy with and without the use of a bipolar vessel-sealing device.
Methods: Of the 49 patients undergoing parotidectomies, a bipolar vessel-sealing device was used for 20. Predictive factors included in the analysis were age, sex, body weight, operating time, tumour pathology, and diabetes mellitus, hypertension and smoking status.
Results: In multivariate analyses, body weight (p = 0.026) and non-use of a bipolar vessel-sealing device (p = 0.009) were significantly associated with increased post-operative drainage after 24 hours. There was also a trend towards increased drainage in diabetic patients. Operating times were significantly shorter in the bipolar vessel-sealing device group.
Conclusion: Although 24-hour drainage appears adequate for most patients, in obese and diabetic individuals there is a risk of requiring increased drainage. Therefore, the drain should be left in place for a longer period. The bipolar vessel-sealing device is safe and time-efficient, and decreases the post-operative drainage period.