Retrospective Cohort Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Aug 14, 2015; 21(30): 9118-9125
Published online Aug 14, 2015. doi: 10.3748/wjg.v21.i30.9118
Diagnostic value of drain amylase for detecting intrathoracic leakage after esophagectomy
Gijs HK Berkelmans, Ewout A Kouwenhoven, Boudewijn JJ Smeets, Teus J Weijs, Luis C Silva Corten, Marc J van Det, Grard AP Nieuwenhuijzen, Misha DP Luyer
Gijs HK Berkelmans, Boudewijn JJ Smeets, Teus J Weijs, Grard AP Nieuwenhuijzen, Misha DP Luyer, Department of Surgery, Catharina Hospital, Michelangelolaan 2, 5623 EJ Eindhoven, The Netherlands
Ewout A Kouwenhoven, Luis C Silva Corten, Marc J van Det, Department of Surgery, ZGT Hospital group Twente, Zilvermeeuw 1, 7609 PP Almelo, The Netherlands
Author contributions: Berkelmans GHK, Smeets BJJ, Kouwenhoven EA and Luyer MDP designed and performed the research; Berkelmans GHK, Smeets BJJ, Kouwenhoven EA, Weijs TJ and Luyer MDP analyzed the data; Berkelmans GHK, Kouwenhoven EA, Smeets BJJ, Weijs TJ, Silva Corten LC, van Det MJ, Nieuwenhuijzen GAP and Luyer MDP wrote the manuscript.
Institutional review board statement: The Medical Ethics Committees United of the Catharina Hospital Eindhoven reviewed and approved this study.
Informed consent statement: Informed consent is given by patients preoperatively and registered in the electronic patient file. All included patients accepted the possibility to collect their patient data.
Conflict-of-interest statement: The authors declare no conflicts of interest.
Data sharing statement: Technical appendix, statistical codes, and the dataset are available from the corresponding author at misha.luyer@cze.nl. Informed consent was obtained as described above.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Misha DP Luyer, MD, PhD, Department of Surgery, Catharina Hospital, Michelangelolaan 2, 5623 EJ Eindhoven, The Netherlands. misha.luyer@cze.nl
Telephone: +31-6-40006809 Fax: +31-40-2443370
Received: February 22, 2015
Peer-review started: February 25, 2015
First decision: April 16, 2015
Revised: April 19, 2015
Accepted: June 9, 2015
Article in press: June 10, 2015
Published online: August 14, 2015
Abstract

AIM: To investigate the value of elevated drain amylase concentrations for detecting anastomotic leakage (AL) after minimally invasive Ivor-Lewis esophagectomy (MI-ILE).

METHODS: This was a retrospective analysis of prospectively collected data in two hospitals in the Netherlands. Consecutive patients undergoing MI-ILE were included. A Jackson-Pratt drain next to the dorsal side of the anastomosis and bilateral chest drains were placed at the end of the thoracoscopic procedure. Amylase levels in drain fluid were determined in all patients during at least the first four postoperative days. Contrast computed tomography scans and/or endoscopic imaging were performed in cases of a clinically suspected AL. Anastomotic leakage was defined as any sign of leakage of the esophago-gastric anastomosis on endoscopy, re-operation, radiographic investigations, post mortal examination or when gastro-intestinal contents were found in drain fluid. Receiver operator characteristic curves were used to determine the cut-off values. Sensitivity, specificity, positive predictive value, negative predictive value, risk ratio and overall test accuracy were calculated for elevated drain amylase concentrations.

RESULTS: A total of 89 patients were included between March 2013 and August 2014. No differences in group characteristics were observed between patients with and without AL, except for age. Patients with AL were older than were patients without AL (P = 0.01). One patient (1.1%) without AL died within 30 d after surgery due to pneumonia and acute respiratory distress syndrome. Anastomotic leakage that required any intervention occurred in 15 patients (16.9%). Patients with proven anastomotic leakage had higher drain amylase levels than patients without anastomotic leakage [median 384 IU/L (IQR 34-6263) vs median 37 IU/L (IQR 26-66), P = 0.003]. Optimal cut-off values on postoperative days 1, 2, and 3 were 350 IU/L, 200 IU/L and 160 IU/L, respectively. An elevated amylase level was found in 9 of the 15 patients with AL. Five of these 9 patients had early elevations of their amylase levels, with a median of 2 d (IQR 2-5) before signs and symptoms occurred.

CONCLUSION: Measurement of drain amylase levels is an inexpensive and easy tool that may be used to screen for anastomotic leakage soon after MI-ILE. However, clinical validation of this marker is necessary.

Keywords: Esophageal cancer, Esophageal surgery, Anastomotic leakage, Amylase, Drain fluid

Core tip: Intrathoracic leakage following esophagectomy is a dreaded complication that requires prompt diagnosis. However, early recognition remains difficult. Elevated drain amylase levels following other types of upper gastrointestinal surgery suggest that the amylase levels may be useful as an early marker for anastomotic leakage following esophagectomy. This study found that the drain amylase levels were higher in patients with proven anastomotic leakage than in patients without anastomotic leakage. This study demonstrates that amylase measurements in drain fluid may be a potential marker for detecting anastomotic leakage after an Ivor-Lewis esophagectomy.