Miniaturized Sensors Registering the Long-Term Course of Suture Tension In Vivo under Varying Intra-Abdominal Pressure

Failure of laparotomy closure develops after up to 20 % of abdominal operations. Suture tension has an influence on the quality of tissue regeneration. No sensors are available to register suture tension dynamics. Methods: In a series of animal experiments, the effects of suture tension on the ultrastructure of the healing incision were examined. Surgeons´ ability to suture with target tension was tested. An implantable sensor and data logger were constructed and tested in sutures closing midline laparotomies in pigs. The influence of elevated intra-abdominal pressure on suture tension dynamics was evaluated. Results: High suture tension has a negative influence on the regeneration of laparotomy incisions. Running sutures for laparotomy closure lose 45 % of their initial tension during 23 hours. Intermittent elevation of intra-abdominal pressure to 30 mm Hg leads to a near total loss of suture tension after 23 hours. Conclusion: Surgeons are not able to control and reproduce suture tension. Suture tension dynamics can be measured in vivo by the sensor developed. Further research is needed to define a tissue specific suture tension optimum to reduce the incidence of complications after laparotomy. Techniques for laparotomy closure need to be modified.