Page 332 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

Chapter 17
Since the research of Jenkins, it has been known that force distributions on the healing abdominal fascia play an important role in the development of IH(8). In patients that received an end colostomy during midline laparotomy, an increased prevalence of IH in those with parastomal hernia (PSH) was found after a mean follow-up of four years. A possible cause for this could be damage to the innervation of the abdominal wall during colostomy creation, leading in turn to atrophy of the abdominal rectus muscle. Furthermore, a non-symmetrical force distribution on the midline laparotomy wound occurs through the creation of a colostomy on the left side of the abdomen. The presence of PSH can increase the risk of the development of IH through both mechanisms.
Unfortunately, optimizing all techniques for closing a midline laparotomy does not reduce the IH rate to zero; in high-risk patients, other interventions might be needed to further reduce its incidence. Prevention of the development of IH with the use of a prophylactic mesh has been investigated for this group. Patients with an abdominal aneurysm or obesity have been found to bene t from prophylactic mesh augmentation; the incidence of IH in these patients was signi cantly reduced, with an odds ratio of 0.25(9, 10). It is not clear if mesh augmentation in an onlay or sublay position is superior in the prevention of IH in high-risk patients. An RCT (PRIMA trial) was initiated to study the best mesh position for preventing IH in high-risk patients(11). Short-term results showed that primary mesh augmentation is safe, with an increase in seroma formation only, after onlay mesh augmentation, and without any increased risk in surgical site infection(12). The results on the incidence of IH after 2 years follow-up are expected in the near future. Since PSH is also a risk factor for IH, prevention of PSH will also reduce the incidence of IH. Another RCT (PREVENT trial) was initiated to investigate the use of a prophylactic mesh reinforcement of a colostomy on the incidence of PSH(13). In this trial, a retromuscular polypropylene mesh was put in place during colostomy creation. The results of 1-year follow-up show a signi cant reduction in the incidence of PSH – from 24 to 4.5% – and no adverse events were found(14). Using prophylactic mesh augmentation of the abdominal wall during laparotomy or colostomy creation seems a safe and e ective means of preventing hernias.
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