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Published on: October 26, 2019
Surgical sutures: coincidence or experience?
K-T von Trotha1, J Grommes2, N Butz3
1Department of Vascular and Endovascular Surgery, University Hospital of the RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany. kvontrotha@ukaachen.de.
Background:
Knotting sutures by hand is still important in daily surgical routine, especially laparotomy closure. The expectation is that hand suturing relies on the experience and subjective estimation of the surgeon. The aim of this study was to investigate whether hand suturing tension is reproducible and if surgical experience influences reproducibility.
Methods:
At the annual Congress of the German Association of Surgery, 118 surgeons performed repetitive sutures on a standardized and certified measuring device simulating the final knot of a fascial closure. Each surgeon was asked to perform five identical single knots in a row using the suture tension that each considered ideal. Tension during knotting was measured in Newtons. The surgeons were divided into five subgroups based on surgical experience: group 1, <1 year; group 2, 2-5 years; group 3, 6-10 years; group 4, 11-20 years; and group 5, >30 years.
Results:
The tension measured at the end of knotting ranged from 0.19 to 10 N. The mean suture tension at endpoint was 3.88 N for group 1 and slightly higher in the other groups, but not significantly different. The overall mean suture tension was 5.43 N and did not correlate with surgical experience. Suture tension was not reproducible.
Conclusion:
Sequential suture tension varied, even among experienced surgeons. The ideal tissue-dependent suture tension has not been defined. Measured values appear to be intuitive, relying on individual feeling rather than the level of experience.

