Remote ischemic postconditioning has a detrimental effect and remote ischemic preconditioning seems to have no effect on small intestinal anastomotic strength

Abstract

Background

The effect of remote pre- and postconditioning on anastomotic healing has been sparsely studied. The aim of our study was to investigate whether remote ischemic conditioning (RIC) applied before and after the creation of a small bowel anastomosis had an effect on anastomotic healing on postoperative day five evaluated by a tensile strength test and histological analysis.

Materials and methods

Twenty-two female piglets were randomized into two groups. The intervention group (n = 12) received RIC on the forelimbs consisting of 15 min of ischemia followed by 30 min of reperfusion before the first end-to-end ileal anastomosis was created. The RIC procedure was repeated and the second and more distal anastomosis was performed. The control group (n = 10) had two similar anastomoses with similar time intervals but without RIC. On postoperative day five, the anastomoses were subjected to macroscopic evaluation, tensile strength test and histological examination.

Results

Mean tensile strength when the first transmural rupture appeared (MATS-2) was significantly lower in the first anastomosis in the intervention group compared to the control group (11.4 N vs 14.7 N, p < .05). Similar result was found by the maximal strength (MATS-3) as defined by a drop in the load curve (12.3 N vs 15.9 N, p < .05). Histologically, a significantly higher necrosis score was found in the anastomosis in the intervention group (1.4 vs 0.8, p < .05). No other significant differences were found.

Conclusions

In conclusion, post-anastomotic remote ischemic conditioning had a detrimental effect and pre-anastomotic conditioning seems to have no effect on small intestinal anastomotic strength.

Keywords:

• Ischemic preconditioning
• ischemic postconditioning
• anastomotic healing
• tensile strength test
• anastomotic leakage

Acknowledgments

The authors are grateful to Lars Hummitzsch for sharing his knowledge and experience with the Chiu et al. grading score.

Author contributions

Mathilde Skov Nygaard and Mie Strandby Jul ensured the creation of the protocol, all necessary approvals, fund raising, the execution of the experimental study, collecting and analyzing the samples. Mathilde Skov Nygaard is the main author of this article. Birgit Debrabant guided the statistical analysis. Gunvor Iben Madsen undertook pathological analysis of the samples. Niels Qvist and Mark Bremholm Ellebæk provided guidance and assistance throughout the whole execution of this project from idea to completion. Mathilde Skov Nygaard and Mie Strandby drafted the manuscript. All authors have actively contributed to the final manuscript.

Disclosure statement

The authors report no proprietary or commercial interest in any product mentioned or concept discussed in this article.

Additional information

Funding

This work was supported by the Odense University Hospital Fund for Free Research [grant numbers A3076 − 05-12-2018], the A.P. Møller Doctors Foundation [18-L-0361 − 08-02-2019] and from the Research Unit for Surgery, Odense University Hospital.