Aiming for complete safety of first trocar insertion of laparoscopic surgery: usefulness of preoperative ultrasonography of umbilical region.

Aim: Vascular or intestinal injuries at the time of the first trocar insertion can cause serious complications during laparoscopic surgeries. In this study, we evaluate the usefulness of ultrasound scans of the umbilical region as well as intraumbilical conditions to help prevent serious complications.

Methods: The subjects included 430 cases who underwent laparoscopic gynecologic surgeries. The umbilical ultrasound scan was performed after tracheal intubation to observe the intestinal movements associated with respiration. Structures of the umbilical region as well as peristalsis and the movement of the intestinal tract were observed. Then, the thickness of the subcutaneous fat (between the umbilical skin surface and the rectus fascia) and the preperitoneal fat (between the rectus fascia and the peritoneum) were measured. The relationship between body mass index (BMI), insertion time of the first trocar and ultrasound measurements were analyzed.

Results: The anatomical structures of the umbilical region (the subcutaneous tissue and the preperitoneal fat) were clearly observed in all cases. The BMI score had a significant relationship with subcutaneous fat thickness (r = 0.547), but remarkably not with preperitoneal fat thickness (r = 0.174). There was no significant relationship between BMI and insertion time. However, insertion time of the first trocar had a significant relationship with preperitoneal fat thickness (r = 0.534).

Conclusions: Preoperative ultrasonography of the umbilical region is asimple process, and it is helpful inpreventing serious complications caused by the first trocar insertion. We have found that preperitoneal fat thickness seems to be an important factor in predicting the potential difficulty of the first trocar insertion.