Retrospective Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Surg. Mar 27, 2016; 8(3): 246-251
Published online Mar 27, 2016. doi: 10.4240/wjgs.v8.i3.246
Changes over time in milk test results following pancreatectomy
Hideki Aoki, Masashi Utsumi, Kenta Sui, Nobuhiko Kanaya, Tomoyoshi Kunitomo, Hitoshi Takeuchi, Norihisa Takakura, Shigehiro Shiozaki, Hiroyoshi Matsukawa
Hideki Aoki, Masashi Utsumi, Kenta Sui, Nobuhiko Kanaya, Tomoyoshi Kunitomo, Hitoshi Takeuchi, Department of Surgery, Iwakuni Clinical Center, Iwakuni 7408510, Japan
Norihisa Takakura, Department of Surgery, Fukuyama City Hospital, Fukuyama 7218511, Japan
Shigehiro Shiozaki, Hiroyoshi Matsukawa, Department of Surgery, Hiroshima City Hospital, Hiroshima 7308518, Japan
Author contributions: Aoki H, Utsumi M, Sui K, Kanaya N and Kunitomo T performed operations; Takeuchi H supervised the research; Aoki H, Takakura N, Shiozaki S and Matsukawa H established milk test; Aoki H wrote this paper.
Institutional review board statement: This study was reviewed and approved by the Iwakuni Clinical Center Institutional Review Board.
Informed consent statement: Patients were not required to give informed consent to this study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: The author declares no conflicts of interest.
Data sharing statement: Participants gave informed consent for data sharing.
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:
Correspondence to: Hideki Aoki, MD, Operation Director, Department of Surgery, Iwakuni Clinical Center, 1-1-1 Atago, Iwakuni 7408510, Japan.
Telephone: +81-827-341000 Fax: +81-827-355600
Received: June 17, 2015
Peer-review started: June 17, 2015
First decision: August 24, 2015
Revised: September 5, 2015
Accepted: December 13, 2015
Article in press: December 15, 2015
Published online: March 27, 2016

AIM: To investigate changes over time in, and effects of sealing technology on, milk test results following pancreatectomy.

METHODS: From April 2008 to October 2013, 66 pancreatic resections were performed at the Iwakuni Clinical Center. The milk test has been routinely conducted at the institute whenever possible during pancreatectomy. The milk test comprises the following procedure: A nasogastric tube is inserted until the third portion of the duodenum, followed by injection of 100 mL of milk through the tube. If a chyle leak is present, the patient tests positive in this milk test based on the observation of a white milky discharge. Positive milk test rates, leakage sites, and chylous ascites incidence were examined. LigaSure™ (LS; Covidien, Dublin, Ireland), a vessel-sealing device, is routinely used in pancreatectomy. Positive milk test rates before and after use of LS, as well as drain discharge volume at the 2nd and 3rd postoperative days, were compared retrospectively. Finally, positive milk test rates and chylous ascites incidence were compared with the results of a previous report.

RESULTS: Fifty-nine milk tests were conducted during pancreatectomy. The positive milk test rate for all pancreatectomy cases was 13.6% (8 of 59 cases). One case developed postoperative chylous ascites (2.1% among the pancreatoduedenectomy cases and 1.7% among all pancreatectomies). Positive rates by procedure were 12.8% for pancreatoduodenectomy and 22.2% for distal pancreatectomy. Positive rates by disease were 17.9% for pancreatic and 5.9% for biliary diseases. When comparing results from before and after use of LS, positive milk test rates in pancreatoduodenectomy were 13.0% before and 12.5% after, while those in distal pancreatectomy were 33.3% and 0%. Drainage volume tended to decrease when LS was used on the 3rd postoperative day (volumes were 424 ± 303 mL before LS and 285 ± 185 mL after, P = 0.056). Both chylous ascites incidence and positive milk test rates decreased slightly compared with those rates from the previous study.

CONCLUSION: Positive milk test rates and chylous ascites incidence decreased over time. Sealing technology may thus play an important role in preventing postoperative chylous ascites.

Keywords: Chylous ascites, Milk test, Pancreatectomy, Surgical energy device, Drain discharge

Core tip: Chylous ascites is sometimes a severe complication of pancreatectomy. We previously reported that the milk test could serve to prevent chylous ascites following surgery. In this study, changes over time in milk test results, and effects of new energy devices on the test results, were investigated. Compared with the first report results, positive milk test rates and chylous ascites incidence were found to have decreased slightly. Use of the new energy devices also tended to result in decreased drainage volume. These findings suggest that the vessel-sealing technology could play an important role in preventing postoperative chylous ascites.