Lipid and volume analysis of neck drainage in patients undergoing neck dissection

We seek to establish normative values for the volume of postoperative neck drainage from patients undergoing ablative oncologic procedures that include a neck dissection and to analyze neck drainage for lipid content to establish guidelines that may be helpful in identifying chylous fistula when this diagnosis is not clinically straightforward.

Neck drainage obtained through continuous suction percutaneous drainage catheters was evaluated following 23 neck dissections performed on 19 patients. In every case, either radicle or modified type I neck dissection was performed. The volume of drainage was quantitated on a day-to-day basis. In a separate group of 27 patients undergoing neck dissection, neck drainage was compared with serum levels of triglyceride, cholesterol, and chylomicron content.

The mean duration of neck drainage was 5 days. Maximum drainage (160 mL) was noted on the first day and dropped daily to less than 10 mL by the fifth postoperative day. A statistically significant difference between serum and neck drainage triglyceride and cholesterol content was observed in nearly all cases. Neck drainage fat content was lower than that noted in serum in nearly all cases. Chylomicron content of 4% was encountered in neck drainage.

This study provides normative data on lipid content of neck drainage. With only a rare exception, the triglyceride and cholesterol levels are higher in the serum than in the neck drainage. A triglyceride level of 100 mg/dL seems to be the upper limit of normal (mean plus 1 standard deviation). A low level of chylomicron (> 4%) is consistent with normal healing and may be due to breakdown of fatty tissue.