ABSTRACT
BACKGROUND: Obstetric anal sphincter injury (OASI) is a serious complication of vaginal births, resulting in possible long-term consequences such as incontinence and pain. Adequate detection and management of these injuries is vital in minimizing the impact they have on women. AIM: To assess the rates of detection, management, and outcomes of OASI before and after the implementation of a new clinical practice guideline and operative pro forma. MATERIALS AND METHODS: A 12-month audit of the incidence, management, and outcomes of OASI was conducted in 2009. An operative pro forma and practice guideline were implemented in 2010 followed by a further audit undertaken between 2010 and 2012. Statistical analysis was performed to determine any significant change in practice. RESULTS: The distribution of risk factors for OASI including primiparity, birthweight, and type of vaginal delivery was similar between the two audited groups. After implementation of the pro forma, the reported incidence of OASI increased from 1.62% to 3.1% (P=0.004). Significant changes in management included an increase in the use of recommended suture material (48% vs 80%, P=0.002), postoperative antibiotics (78% vs 99%, P=0.001), postoperative catheterization (52% vs 90%, P<0.001), and inpatient physiotherapy consultations (44% vs 97%, P=<0.001). An increase was seen in women attending their 6-week follow-up appointment (33% vs 54% P=0.058); however, this was just below the level of statistical significance. CONCLUSION: The introduction of the new pro forma and guideline resulted in an increase in the reported incidence of OASI, improved management, and follow-up of patients.
ABSTRACT
AIMS: Investigate risk factors for obstetric anal sphincter injury (OASI) and their incidence between 2006 and 2010 at a regional teaching hospital in Australia. Determine whether a correlation exists between a decrease in OASI rates and an increase in mediolateral episiotomies. MATERIALS AND METHODS: A retrospective observational study conducted at the Geelong Hospital, Barwon Health, Victoria, Australia. Every adequately documented vaginal birth from 2006 to 2010 in the hospital was included (N = 7314, cases of OASI = 239). Patient data were obtained from the Barwon Health Birth Outcomes System database. Multinomial logistic regression, Pearson's correlation coefficient and relative risk calculations were used for analysis. RESULTS: Risk factors for OASI include nulliparity (OR 2.64, 95% CI 1.95-3.57, P < 0.01), instrumental delivery (OR 2.54, 95% CI 1.82-3.55, P < 0.01) and birth weight greater than 4 kg (OR 1.56, 95% CI 1.11-2.19, P = 0.01). There was a significant correlation between increasing mediolateral episiotomy use from 12.56% to 20.10% and a reduction in OASI rates over the 5-year period (Pearson's correlation coefficient: -0.94, P = 0.02). The correlation remained when analysing normal vaginal births in isolation from instrumental (Pearson's correlation coefficient: -0.89, P = 0.04). CONCLUSIONS: Clear risk factors for OASI include nulliparity, macrosomia and instrumental delivery. There was a significant correlation between increasing mediolateral episiotomy rates from 12.56% to 20.10% and decreasing OASI.
