Page 50 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

Chapter 3
muscle tissue was avoided. The conventional large tissue bites or mass closure technique was applied with tissue bites of at least 1 cm and intersuture spacing of 1 cm with USP 1 double loop PDS Plus II (Ethicon) with a 48 mm needle. In both groups, suturing was started at both ends of the incision towards the centre where an overlap of at least 2 cm of both the cranial and caudal sutures was created and both sutures were separately knotted. An additional knot from both the cranial and caudal sutures was allowed. The number of stitches was counted, wound length and length of the remaining suture measured, and ratio of suture length to wound length calculated by dividing the length of the suture used to close the fascia by the wound length. For both suture techniques, we aimed for a suture length to wound length ratio of 4:1 or higher(14). Patients were invited for follow-up at the outpatient clinic 1 month and 1 year after surgery. The 1 year follow-up visit was de ned as a follow-up visit up to month 15 after surgery. During these visits patients underwent physical examination by a medical doctor and abdominal ultrasonography by a radiologist, both of whom were masked to group allocation. Any abdominal CT done after surgery was also used to identify the presence or absence of incisional hernia. Physical examination and assessment of CT of all patients was done by two medical doctors (EBD and JJH) specially trained for this trial. Patients who did not attend the outpatient clinic received a repeated invitation or were o ered a home visit. In case of con icting observations, the observation by radiological imaging was decisive. Patients were regarded as censored observations if they underwent re-laparotomy through midline incision, were deceased, or ended follow-up. Patients remained unaware of the type of closure until completion of follow-up. All participants were asked to ll out quality of life questionnaires preoperatively and at 1, 3, 6, and 12 months postoperatively. We assessed quality of life with the Short Form-36 (SF-36) and the EuroQoL-5D (EQ-5D) questionnaires(16, 17). EQ-5D includes a visual analogue scale to rate overall health status on a scale of 0 (worst imaginable health state) to 100 (best imaginable state). Additionally, in the rst postoperative week, patients scored their pain on a visual analogue scale once a day.
Outcomes
The primary outcome was the occurrence of incisional hernia during follow-up. We used the de nition of incisional hernia from the European Hernia Society (EHS):“any abdominal wall gap with or without bulge in the area of a postoperative
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