Prevention of incisional hernia with retrorectus synthetic mesh versus biological mesh following loop ileostomy closure (Preloop trial)

BACKGROUND

The rate of incisional hernia after closure of a temporary loop ileostomy is significant. Synthetic meshes are still commonly avoided in contaminated wounds. The Preloop trial was a multicentre RCT designed to evaluate the benefits of synthetic mesh in incisional hernia prevention, and its safety for use in a contaminated surgical site compared with biological mesh.

METHODS

Study patients who underwent closure of a loop ileostomy after anterior resection for rectal cancer were assigned to receive either retrorectus synthetic or biological mesh to prevent incisional hernia. The primary outcomes were surgical-site infections within 30 days, and clinical or radiological incisional hernia incidence at 10 months. Secondary outcomes were reoperation rate, operating time, duration of hospital stay, other complications within 30 days of surgery, 5-year quality of life measured by RAND-36, and incisional hernia incidence within 5 years of follow-up.

RESULTS

Between November 2018 and September 2021, 102 patients were randomised, of whom 97 received the intended allocation. At 10-month follow-up, 90 patients had undergone clinical evaluation and 88 radiological evaluation. One patient in each group (2 per cent) had a clinical diagnosis of incisional hernia (P = 0.950) and one further patient in each group had a CT-confirmed incisional hernia (P = 0.949). The number of other complications, reoperation rate, operating time, and duration of hospital stay did not differ between the study groups.

CONCLUSION

Synthetic mesh appeared comparable to biological mesh in efficacy and safety for incisional hernia prevention at the time of loop ileostomy closure.

REGISTRATION NUMBER

NCT03445936 (http://www.clinicaltrials.gov).

Synthetic mesh versus biological mesh to prevent incisional hernia after loop-ileostomy closure: a randomized feasibility trial

BACKGROUND

Incisional hernia is a frequent complication after loop-ileostomy closure, rationalizing hernia prevention. Biological meshes have been widely used in contaminated surgical sites instead of synthetic meshes in fear of mesh related complications. However, previous studies on meshes does not support this practice. The aim of Preloop trial was to study the safety and efficacy of synthetic mesh compared to a biological mesh in incisional hernia prevention after loop-ileostomy closure.

METHODS

The Preloop randomized, feasibility trial was conducted from April 2018 until November 2021 in four hospitals in Finland. The trial enrolled 102 patients with temporary loop-ileostomy after anterior resection for rectal cancer. The study patients were randomized 1:1 to receive either a light-weight synthetic polypropylene mesh (Parietene Macro™, Medtronic) (SM) or a biological mesh (Permacol™, Medtronic) (BM) to the retrorectus space at ileostomy closure. The primary end points were rate of surgical site infections (SSI) at 30-day follow-up and incisional hernia rate during 10 months' follow-up period.

RESULTS

Of 102 patients randomized, 97 received the intended allocation. At 30-day follow-up, 94 (97%) patients were evaluated. In the SM group, 1/46 (2%) had SSI. Uneventful recovery was reported in 38/46 (86%) in SM group. In the BM group, 2/48 (4%) had SSI (p > 0.90) and in 43/48 (90%) uneventful recovery was reported. The mesh was removed from one patient in both groups (p > 0.90).

CONCLUSIONS

Both a synthetic mesh and biological mesh were safe in terms of SSI after loop-ileostomy closure. Hernia prevention efficacy will be published after the study patients have completed the 10 months' follow-up.

Sphincter rupture and anal incontinence after first vaginal delivery

BACKGROUND

The aim of this prospective study was to establish the incidence of anal incontinence and sphincter defects after first vaginal delivery.

METHODS

A total of 99 nulliparous and pregnant women were examined prospectively 4 weeks (mean) before delivery and 4 months (mean) after delivery. Of the study population, 75 (76%) women had vaginal delivery and 24 (24%) had cesarean section. Vacuum extraction was necessary in 20 (20%) cases. The symptoms of anal incontinence were asked about using a standard questionnaire. Clinical examination, endoanal ultrasound (EAUS) and anal manometry were performed before and after delivery.

RESULTS

The symptoms of mild anal incontinence, mainly gas incontinence, increased after vaginal delivery more than after cesarean section (P < 0.032). Occult anal sphincter defects were noted in 17 (23%) of the 75 women after vaginal delivery by using EAUS. After vacuum extraction, anal sphincter defects were noted in nine (45%) out of 20 women. No new sphincter defects were found in the cesarean section group. The maximal squeezing pressures were significantly decreased in the patients with external anal sphincter (EAS) defects (P = 0.0025). Vacuum extraction leads to more sphincter defects but does not significantly increase anal incontinence or decrease mean anal sphincter pressures.

CONCLUSIONS

The first vaginal delivery can result in occult sphincter defects and the use of vacuum extraction increases the risk.

Primary sphincter repair: are the results of the operation good enough?

PURPOSE

This study was designed to evaluate the clinical outcome of primary anal sphincter repair caused by obstetric tears and to analyze possible risk factors associated with sphincter rupture during vaginal delivery.

METHODS

A total of 52 females with a third-degree or fourth-degree perineal laceration during vaginal delivery were examined. The symptoms of anal incontinence were obtained by a standard questionnaire. In addition to a clinical examination, endoanal ultrasound, anal manometry, and pudendal nerve terminal motor latency examinations were performed. A control group consisted of 51 primiparous females with no clinically detectable perineal laceration after vaginal delivery.

RESULTS

After primary sphincter repair, 31 females (61 percent) had symptoms of anal incontinence. Fecal incontinence occurred in 10 females (20 percent). According to Hardcastle and Parks' and Jorge and Wexner's classifications, the study group had more severe symptoms of anal incontinence than the control group (P<0.001 in both classification groups). In endoanal ultrasound examination, a persistent defect of the external anal sphincter was found in 39 females (75 percent) in the rupture group compared with 10 females (20 percent) in the control group (P<0.001). Anal sphincter pressures were significantly lower in the rupture group than in the control group. An abnormal presentation was the only risk factor for anal sphincter rupture during vaginal delivery.

CONCLUSIONS

After primary sphincter repair, persistent external anal sphincter defect and symptoms of anal incontinence are common in females who have had a primary sphincter repair after vaginal delivery. The means of improving the results of primary repair should be studied further.