Intraoperative assessment of colorectal anastomotic integrity: a systematic review.
BACKGROUND
Surgeons have attempted to minimize postoperative anastomotic complications by employing intraoperative tests and manoeuvres to assess colorectal anastomotic integrity. These have evolved over time with improvement in operative technology and techniques. This systematic review aims to examine the impact of such intraoperative assessments.


METHODS
A systematic review of studies assessing intraoperative anastomotic assessments and their impact on postoperative anastomotic complications was performed. Intraoperative measures undertaken as a result of intraoperative assessments and postoperative anastomotic complications were analysed.


RESULTS
37 Studies were identified. 13 studies evaluated basic mechanical patency tests, ten studies evaluated endoscopic visualisation techniques and 14 studies evaluated microperfusion techniques. Postoperative anastomotic complications were significantly lower in patients tested with basic mechanical patency tests compared to those untested (non-RCT: 4.1 vs. 8.1 %, p = 0.03, RCTs: 5.8 vs. 16.0 %, p = 0.024). There were no differences in postoperative anastomotic complications between tested and non-tested cohorts in non-randomised cohort studies evaluating endoscopic visualisation techniques. However, intraoperative measures taken after abnormal intraoperative tests may have reduced the number of postoperative complications. Perfusion analysis techniques are not in routine widespread clinical practice as yet, but newer techniques such as fluorescent dyes and imaging under near infrared light show technical feasibility.


CONCLUSIONS
Intraoperative colorectal anastomotic assessment has evolved together with advancement of technology in the surgical setting. Moderate benefit in terms of lower postoperative anastomotic complications has been shown with basic mechanical patency testing and more recently with intraoperative endoscopic visualisation of colorectal anastomoses. The next advance and possible introduction into routine practice may include the use of microperfusion techniques. The latest in this group of techniques, which utilise autofluorescent dyes such as Indocyanine green, hold great potential. Well-planned controlled studies or ideally, randomised controlled trials need to be conducted to further assess the benefit of these latest techniques.
Surgical Epidemiology, Trials and Outcome Centre (SETOC), St Mark's Hospital and Academic Institute, Harrow, Middlesex, HA1 3UJ, UK, s.nachiappan12@imperial.ac.uk.
Subramanian
S
Nachiappan
Alan
A
Askari
Andrew
A
Currie
Robin H
RH
Kennedy
Omar
O
Faiz
D000714:Anastomosis, Surgical / Q000379:methods; D003106:Colon / Q000601:surgery*; D004396:Coloring Agents / Q000737:chemistry; D006801:Humans; D007208:Indocyanine Green / Q000737:chemistry; D016343:Monitoring, Intraoperative / Q000379:methods; D011183:Postoperative Complications / Q000453:epidemiology / Q000517:prevention & control*; D012007:Rectum / Q000601:surgery*
D004396:Coloring Agents; D007208:Indocyanine Green