Thyroid drains and postoperative drainage

To evaluate postoperative drainage in patients undergoing thyroid lobectomy versus total thyroidectomy and to establish a correlation between intraoperative blood loss and postoperative drainage.

Case series with planned data collection.

Tertiary medical center.

Consecutive patients (n = 100) undergoing thyroid surgery from October 2006 through November 2008 were examined. Data collected included age, gender, postoperative drainage, estimated intraoperative blood loss, type of surgery, length of hospital stay, pathology, and postoperative complications. Standard descriptive statistics were used to summarize characteristics of subjects, surgical procedures, and outcomes. Spearman rank correlation was used to evaluate association of drainage with blood loss and Kruskal-Wallis test to compare results by surgery type.

There were 100 surgeries performed: 52 lobectomies and 48 total thyroidectomies. Total postoperative drainage ranged from 0 to 230 mL, median was 32 mL. Estimated intraoperative blood loss ranged from 10 to 300 mL, median was 20 mL. We noted a statistically significant association of postoperative drainage with intraoperative blood loss (r = 0.39, P < 0.001), but substantial variability in drainage was observed even among patients with similar blood loss. Although there was significantly less drainage among thyroid lobectomies (P = 0.012), the distributions were quite similar apart from 10 patients (9 lobectomy) with exceptionally low drainage.

There was a statistically significant association of postoperative drainage with intraoperative blood loss and significantly less postoperative drainage among patients undergoing thyroid lobectomies. However, the observed associations do not appear to be strong enough to accurately predict patients who will experience substantial drainage.