Randomized trial comparing episiotomies with Braun-Stadler episiotomy scissors and EPISCISSORS-60(®)

Episiotomy angle is a crucial factor in causation of obstetric anal sphincter injuries (OASIS), which are the major cause of female bowel incontinence. Sutured episiotomies angled too close to the midline (<30 degree) or too far away from the midline (>60 degree) fail to unload the perineum sufficiently and predispose to OASIS. A 25-degree post-delivery episiotomy suture angle has a 10% risk of OASIS while 45-degree episiotomy is associated with 0.5% risk. To account for perineal distension at crowning, a 60-degree episiotomy incision is required to achieve 43-50 degree suture angles. We compared episiotomy suture angles with commonly used Braun-Stadler episiotomy scissors with the new fixed angle EPISCISSORS-60(®).

Ethical approval was obtained. A prospective cluster randomization design was chosen. Thirty-one patients were required in each group for a 12-degree difference with power at 90% and 5% significance. Sutured episiotomy angles and post-delivery linear distance from caudal end of the sutured episiotomy to the anus were measured with protractors and rulers. Two-tailed t-tests were used to compare the two groups.

Thirty-one nulliparae had episiotomies with EPISCISSORS-60(®), 32 with Braun-Stadler. Mean age (25 versus 24.8 years) was similar. EPISCISSORS-60(®) episiotomies were angled 12 degrees more laterally away from the anus compared to Braun-Stadler (40.6 degrees, 95% confidence interval [CI] ±2, interquartile range [IQR] 35-45 versus 28.3 degrees, 95% CI ±2, IQR 25-30, P<0.0001). The post-delivery linear distance from caudal end of the sutured episiotomy to the anus was 15 mm more with the EPISCISSORS-60(®) compared to Braun-Stadler (35 mm, 95% CI ±2.2, IQR =30-39 versus 19.5; 95% CI ±1.3, IQR =14.75-22.25 P<0.0001). EPISCISSORS-60(®) episiotomies measured longer (47 mm versus 40 mm, P<0.0001). There were no OASIS cases in the EPISCISSORS-60(®) group versus one in the Braun-Stadler group.

The EPISCISSORS-60(®) sutured episiotomies are much further away from the midline in angular and distance measures, hence at lower OASIS risk.