Early Drain Amylase Value Predicts the Occurrence of Pancreatic Fistula After Pancreaticoduodenectomy
We thank Dr Fernandes Teixeira and colleagues for their interest in our article that analyzed the utility of POD 1 drain amylase levels as a predictor of postoperative pancreatic fistula (PF). Indeed, early prediction of PF after pancreatic resection has been garnering interest because of its implications on postoperative management in an era of increased scrutiny of healthcare expenditure and Enhanced-Recovery After Surgery protocols.1 Early, accurate prediction of postoperative PF formation allows surgeons to safely discharge low-risk patients under a fast-track protocol, thereby allowing for cost-efficient care without compromising patient safety.
In a similar effort at their institution, Dr Fernandez Teixeira and colleagues anecdotally report on a cohort of patients with high postoperative day (POD 1) drain amylase levels that subsequently normalized, only to develop clinically significant PFs late postoperatively. They express concerns that our reported PF incidence of 31.4% in the high POD 1 drain amylase level cohort may be an underestimation, and that perhaps the reported 25.7% readmission rate could be reduced if these patients were kept under close observation.2
The reported PF rate in our article reflects its postoperative occurrence including those cases that were identified on follow-up and is not limited to in-hospital occurrences. However, the concerns from the authors are valid, and it should be highlighted that PF can indeed manifest late in the postoperative course. In a separate study analyzing readmissions after pancreaticoduodenectomy, the median time from discharge to PF-related readmission was 6.5 days, suggesting that many PFs occur for more than 7 days postoperatively.3 We fully agree that patients with high POD 1 drain amylase levels should be kept under closer observation, even if the drain amylase decreases later in the course and the drain is removed. It would not be appropriate to extend the length of stay for these patients, however, because more than 2 of 3 of them will not have a fistula. Perhaps follow-up phone calls and instructions regarding the signs and symptoms of a possible fistula should be implemented. In our current healthcare climate where hospitals are pressured to do more with less, it is important that we reduce hospital length of stay safely and responsibly. It is just as important to recognize that with increasing amount of patients being discharged early, readmissions will be necessary to manage patients who develop late postoperative complications. What our study shows is that a low POD 1 drain amylase level has a very strong predictive value for absence of fistula, and therefore allows for risk profiling of patients after pancreaticoduodenectomy for safe early discharges. Of the remaining patients, some will continue with a high drain amylase through their hospital course, and by definition, have a fistula. Most of those with an initial high amylase that subsequently normalizes will go on to have an uneventful course, but some will have delayed presentation of a fistula, and the clinician should be aware of this.