Bile acid in drainage fluid for early diagnosis of anastomotic leakage and safe discharge after minimally invasive rectal cancer resection: A prospective cohort study

Background

This study was designed to evaluate the diagnostic value of bile acid levels in drainage fluid for early prediction and exclusion of anastomotic leakage, and assess the performance in allowing a safe discharge.

Methods

This prospective single-center study was conducted in patients diagnosed with rectal cancer who had received minimally invasive anterior resection consecutively from December 2021 to March 2024. Bile acid in drainage fluid, C-reactive protein, and procalcitonin in serum were measured on the third and fifth day after surgery. Four criteria were considered in discharging patients: a C-reactive protein level below 100 mg/L, flatus with or without defecation, a restore of liquid diet, a bile acid level less than 2 μmol/L.

Results

A total of 419 patients were included and divided into an anastomotic leakage group (n = 37; 8.8%) and a nonanastomotic leakage group (n = 382; 91.2%). Of those patients, 384 accorded with the discharge criteria and 380 of them (99%) discharged safely. The rate of anastomotic leakage after discharge and readmission was 0.5% and 0.3%. Bile acid levels in drainage fluid in the anastomotic leakage group were significantly greater than that in the nonanastomotic leakage group on both postoperative days 3 and 5 (postoperative day 3: 3.00 [2.00–5.17] μmol/L vs 0.80 [0.40–1.30] μmol/L, P < .001; and postoperative day 5: 5.17 [3.00–9.20] μmol/L vs 2.00 [1.40–3.50] μmol/L, P < .001). The negative predictive value in ruling out an anastomotic leakage were 0.96 on postoperative day 3 and 0.97 on postoperative day 5 for bile acid alone.

Conclusion

Drainage bile acid has a high negative predictive value in the early diagnosis of anastomotic leakage and showed potential to allow for safe discharge.