Utility of drain fluid amylase measurement on the first postoperative day after pancreaticoduodenectomy.

BACKGROUND

Early detection of pancreatic fistula (PF) may improve the outcome after pancreaticoduodenectomy, and exclusion of PF may allow earlier drain removal and accelerate recovery. The aim of the present study was to evaluate the relationship between drain fluid amylase on the first postoperative day (DFA(1)) and PF.

PATIENTS AND METHODS

This work was designed as a prospective study and included patients undergoing pancreaticoduodenectomy in a single center. For each patient, DFA was measured on the first and fifth postoperative days, and PF was defined by drainage of amylase-rich fluid on the fifth postoperative day (DFA(5) >300 U/l). A cut-off value of DFA(1) was derived, which yielded sensitivity and negative predictive value of 100% for predicting a PF.

RESULTS

A total of 70 patients (47% male) who underwent pancreaticoduodenectomy (Whipple procedure: 37; pylorus-preserving procedure: 33) between April 2009 and March 2010 were included. Nine of those patients developed a PF (grade A-2; B-5; C-2). There were two postoperative deaths (3%). The DFA(1) value significantly correlated with DFA(5) (Spearman rank coefficient 0.68; p < 0.0001). The median DFA(1) of patients with a PF (6,205; range 357-23,391) was significantly higher than in patients without a PF (69; range 5-5,180; p = 0.01; unpaired t test). No patient with a PF had a DFA(1) ≤350 U/l, compared to 48/61 patients (79%) without a PF. Using 350 U/l as a cut-off, a low DFA(1) excluded a PF with a sensitivity, specificity, positive and negative predictive values of 100, 79, 41, and 100%, respectively.

CONCLUSIONS

Drain fluid amylase on the DFA(1) after pancreaticoduodenectomy stratifies patients according to likelihood of developing a PF.