Can transperineal ultrasound improve the diagnosis of obstetric anal sphincter injuries?

INTRODUCTION AND HYPOTHESIS: Women with missed obstetric anal sphincter injuries (OASIs) are at an increased risk of anal incontinence. Our aim was to assess the accuracy of three-dimensional (3D) transperineal ultrasound (TPUS) compared with clinical examination for detecting OASIs. METHODS: A cross-sectional study of women undergoing their first vaginal delivery. Perineal trauma was initially assessed by the doctor or midwife performing the delivery (accoucheur) and women were then re-examined by the trained research fellow (KW). A 3D TPUS was performed immediately after delivery before suturing to identify OASIs. The research fellow's clinical diagnosis was used as the reference standard. A power calculation determined that 216 women would be required for the study. RESULTS: Two hundred and sixty-four women participated and 226 (86%) delivered vaginally. Twenty-one (9%) sustained OASIs. Six (29%) of these tears were missed by the accoucheur but were identified by the research fellow. TPUS identified 19 of the 21 (90.5%) OASIs. One percent (n = 2) had sonographic appearances of an anal sphincter defect that was not seen clinically. The positive and negative predictive value of TPUS to detect OASIs was 91% and 99% respectively. TPUS identified 91% of OASIs compared with 71% detected by the accoucheur, which was not statistically significant. CONCLUSIONS: The detection rate of OASIs with TPUS and with the clinical findings of the accoucheur was similar. Given the training and financial implications needed for TPUS, attention needs to be focused on the training of midwives and doctors to identify anal sphincter injuries by clinical examination.

Is there a role for transperineal ultrasound imaging of the anal sphincter immediately after primary repair of third degree tears?

OBJECTIVE: When obstetric anal sphincter injuries are identified, it is crucial that the defects are repaired appropriately to achieve a better outcome. Although the presence of an intact anal sphincter is not the sole mechanism for maintaining continence, and not all women with an anal sphincter defect are symptomatic, there is an association between sphincter defects and anal incontinence. Our aim was to evaluate whether transperineal ultrasound (TPUS) is useful in assessing anal sphincter integrity immediately following primary repair of obstetric anal sphincter injuries (OASIs). STUDY DESIGN: This is a prospective observational study of women who sustained OASIs during their first vaginal delivery. Three dimensional (3D) TPUS was performed immediately after repair of OASIs to identify anal sphincter defects. A repeat TPUS was performed 12 weeks following repair. RESULTS: 21 women sustained OASIs of whom 20 (95%) attended follow up. Eight (40%) had a grade 3a tear and 12 (60%) a 3b tear. 8/20 (40%) women had residual external anal sphincter (EAS) defects identified by TPUS immediately after repair. Of these eight defects, six (75%) persisted at 12 weeks postpartum. No new defects were seen at follow up among the twelve women in whom no defect was seen immediately following the repair. Six residual EAS defects were found at 12 weeks postpartum. An EAS defect at 12 weeks postpartum was associated with anal incontinence (p = 0.04). Women with 3b tears were more likely to have anal incontinence (AI) and residual sonographic EAS defects when compared with 3a tears but this was not statistically significant. CONCLUSIONS: Women who had no TPUS defect detected immediately following primary repair of OASIs, remained as such at 12 weeks postpartum. Of those in whom a defect was seen immediately after repair, it persisted in 75% of cases at 12 weeks. We believe that the value of TPUS immediately after repair appears to be limited and would need to be defined if it were to be considered for routine practice. Further research on its role immediately after repair of major tears (Grade 3C/4) is needed. In addition, performing ultrasound would require widespread training of obstetricians to develop expertise. This highlights the importance of adequate training of obstetricians in OASI repair.

Are Women's and Obstetricians, Views on Mode of Delivery Following a Previous Cesarean Section Really OCEANS Apart?

PURPOSE: Most women with one previous cesarean section (CS) are suitable for either a vaginal birth after CS (VBAC) or an elective repeat CS. Previously, nurse-led prenatal education and support groups have failed to have an impact on the mode of delivery, which women opted for after one CS. A novel one-stop obstetrician-led cesarean education and antenatal sessions (OCEANS) has been developed to inform and empower women in their decision-making following one previous CS. The objective of our study was to evaluate how OCEANS influences the mode of delivery for women who have previously had one CS. STUDY DESIGN: Two-hundred and sixty-six women who had a single previous lower segment CS were invited to attend OCEANS, which is a 1-h discussion group of women between 5 and 15 in number, facilitated by an experienced obstetrician. Data were collected prospectively on women who were invited to attend OCEANS over a 12-month period commencing on the 1st January 2012. RESULTS: 188 (71 %) attended the group, while 20 (8 %) canceled their appointment and 58 (22 %) did not keep their appointment. Those who attended OCEANS were 38 % more likely to opt for a VBAC than those who did not attend. There was no difference in the rates of successful vaginal delivery between women who attended OCEANS and those who did not (56 vs. 61 %, p = 0.55). CONCLUSIONS: While nurse-led prenatal education and support groups have no impact on mode of delivery after one CS, a dedicated obstetrician-led clinic increases the rate of those opting for VBAC by 38 %. Such clinics may be a useful tool helping in empowering women in their decision-making and reduce the rate of CSs.

Mediolateral episiotomy: are trained midwives and doctors approaching it from a different angle?

OBJECTIVES: The angle at which a mediolateral episiotomy is incised is critical to the risk of obstetric anal sphincter injuries (OASIS). When a mediolateral episiotomy is incised at least 60 degrees from the midline it is protective to the anal sphincter. The objective of our study was to investigate how accoucheurs described and depicted a mediolateral episiotomy. STUDY DESIGN: One hundred doctors and midwives were invited to complete an interview-administered questionnaire in a district general hospital in the United Kingdom over a 10-month period commencing in August 2012. Accoucheurs were asked to describe the angle at which they would cut a mediolateral episiotomy, and to depict this on a pictorial representation of the perineum. The angle drawn was calculated by an investigator blinded to the participant's initial description of a mediolateral episiotomy. RESULTS: Sixty-one midwives and 39 doctors participated. Doctors and midwives stated they would perform a mediolateral episiotomy at an angle of 45 degrees from the midline, but midwives depicted episiotomies 8 degrees closer to the midline (37.3 degrees vs. 44.9 degrees, p=0.013) than they described. Seventy-six percent of accoucheurs had undergone formal training in how to perform a mediolateral episiotomy, but this had no impact on their clinical practice. Accoucheurs who had been supervised for ten episiotomies before independent practice performed them in keeping with the angle they described. CONCLUSIONS: Doctors and midwives are unaware of the appropriate angle (60 degrees) at which a mediolateral episiotomy should be incised at to minimise obstetric anal sphincter injury. The correct angle should be emphasised to accoucheurs to minimise the risk of anal sphincter damage. In addition midwives depict episiotomies that are significantly more acute than they describe. Accoucheurs should also perform at least 10 episiotomies under supervision prior to independent practice. Training programmes should be devised and validated to improve visual measurement of the episiotomy incision angle at crowning. Consideration should also be given to the development of novel surgical devices that help the accoucheur to perform a mediolateral episiotomy accurately.

Anal and urinary incontinence 4 years after a vaginal delivery.

INTRODUCTION AND HYPOTHESIS: Our purpose was to establish the incidence of anal and urinary incontinence 4 years following vaginal delivery in women with and without obstetric anal sphincter injuries (OASIS). METHODS: This was a prospective study of 241 having their first vaginal delivery who had independent verification and repair of OASIS by trained obstetricians. All obstetricians performing OASIS repairs had undergone structured hands-on training and were then directly supervised while repairing OASIS until they were deemed competent to repair independently. Patients were followed up for 4 years with validated bowel and urinary questionnaires. In order to minimise nonresponders, contact details were verified and obtained from their general practitioners, the local primary care trust and electoral roll. RESULTS: Two hundred and fifty-four women were invited, and 241 (95 %) participated. Fifty-nine (25 %) women sustained OASIS. One hundred and forty-nine were contactable 4 years later, and 86 (58 %) agreed to participate in the study at 4 years. No woman had faecal incontinence, and there was no difference in rates of flatus incontinence prior to delivery up to 4 years postpartum, regardless of whether OASIS occurred or not. Urinary incontinence was more than four times more common after vaginal birth, and this was not affected by whether OASIS occurred and resulted in a significant deterioration in quality of life. CONCLUSIONS: The previously reported higher rates of anal incontinence following OASIS can be minimised up to 4 years after delivery if repaired by trained doctors. There is a significant increase in urinary incontinence following vaginal delivery, and the mechanism for this is not linked to anal sphincter disruption.

Outcome of obstetric anal sphincter injuries (OASIS)--role of structured management.

INTRODUCTION AND HYPOTHESIS: Prospective studies up to 1 year after repair of obstetric anal sphincter injuries (OASIS) report anal incontinence in 33% of women and up to 92% have a sonographic sphincter defect. The aim of this study is to determine the outcome of repair by doctors who have undergone structured training using a standardized protocol. METHODS: Doctors repaired OASIS after attending a training workshop. The external anal sphincter was repaired by the end-to-end technique when partially divided and the overlap method when completely divided. Endoanal ultrasound was performed prior to suturing and 7 weeks later. A validated bowel symptom questionnaire was completed prior to delivery, at 7 weeks postpartum, and at 1 year postpartum. RESULTS: Fifty-nine women sustained OASIS. At 7 weeks, six (10%) had a defect on ultrasound. There was no significant deterioration in symptoms of fecal urgency, incontinence, or quality of life at 1 year after delivery. CONCLUSIONS: The 1-year outcome after repair of OASIS appears to be good when repaired by doctors after structured training.

Structured hands-on training in repair of obstetric anal sphincter injuries (OASIS): an audit of clinical practice.

We conducted an audit to evaluate how effective a structured course in the management of obstetric anal sphincter injuries (OASIS) was at imparting knowledge. Training was undertaken using models and cadaveric pig's anal sphincters. An anonymous questionnaire was completed prior to and 8 weeks after the course. Four hundred and ninety seven completed the questionnaire before and 63% returned it after the course. Prior to the course, participants performed on average 14 OASIS repairs independently. Only 13% were satisfied with their level of experience prior to performing their first unsupervised repair. After the course, participants classified OASIS more accurately and changed to evidence-based practice. Particularly, there was a change in identifying (60% vs. 90%; P < 0.0001) and repairing the internal sphincter (60% vs. 90%; P < 0.0001). This audit demonstrated that training in the management of OASIS is suboptimal. Structured training may be effective in changing clinical practice and should be an adjunct to surgical training.

Urinary incontinence after obstetric anal sphincter injuries (OASIS)--is there a relationship?

This study aimed to compare urinary symptoms and its impact on women's quality of life after obstetric anal sphincter injuries (OASIS) with a matched control group in the short term. The study group consisted of 100 primiparous women with OASIS and 104 controls who sustained a second-degree tear or had a mediolateral episiotomy performed. All women completed a validated International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF) questionnaire 10 weeks after delivery. Compared to controls, significantly more women with OASIS reported overall urinary incontinence (21.2 vs 38%, p = 0.005) and had significantly worse quality of life score (incontinence score: 2.42 vs 1.2; p = 0.008). Significantly more women with OASIS suffered from stress urinary incontinence (33 vs 14%; p = 0.002; OR 3.06; CI = 1.54-6.07) than controls. Logistic regression analysis revealed that OASIS and a prolonged (>50 min) second stage of labour were independent risk factors for the development of stress urinary incontinence. This study highlights the importance of inquiring about urinary incontinence in women with OASIS.

Evaluation of postpartum perineal pain and dyspareunia--a prospective study.

OBJECTIVE: Postpartum perineal pain and dyspareunia have been reported to affect 42% of women within the first 2 weeks after their first vaginal delivery. We aimed to determine the prevalence of dyspareunia and perineal pain using validated pain scores following accurate classification of perineal trauma according to the guidelines of the Royal College of Obstetricians and Gynaecologists. STUDY DESIGN: Prospective study of women having their first vaginal delivery. All women had a perineal and rectal examination. Pain was assessed with a 4-point Verbal Rating Score and an 11-point visual analogue scale on day 1, day 5 and 2 months after delivery. RESULTS: Two hundred and fifty-four women were invited and 95% participated. Ninety-two percent experienced perineal pain on day one, resolving in 88% (p<0.001) at 2 months. Compared to an intact perineum or first degree tear significantly more women experienced perineal pain after a second, third or fourth degree tear. Forty percent resumed coitus within 2 months regardless of whether perineal trauma occurred or not. Five days after delivery, uncomplicated episiotomies resulted in more perineal pain than second degree tears. CONCLUSIONS: Although perineal pain affected 92% of mothers, it resolved in the majority within 2 months of delivery. Obstetric anal sphincter injury is associated with more perineal pain than other perineal trauma. Spontaneous second degree tears cause less perineal pain than episiotomies. The 11-point visual analogue scale may be more sensitive than the 4-point Verbal Rating Score.

Risk factors for obstetric anal sphincter injury: a prospective study.

BACKGROUND: Anal incontinence is an embarrassing condition that is largely underreported. Obstetric anal sphincter injuries are the major etiological factor. Recognition of risk factors may minimize the development of sphincter injuries. The objective of this study was to identify risk factors for sphincter injuries and measure dimensions of mediolateral episiotomies. METHODS: Women expecting their first vaginal delivery were invited to participate, and an experienced research fellow performed a perineal and rectal examination and classified tears according to the new international classification. Dimensions of episiotomies were measured and obstetric variables recorded prospectively. RESULTS: Of the 241 women recruited, 59 (25%) sustained sphincter injuries. Univariate analysis revealed that forceps delivery OR 4.03 (1.63-9.92), vacuum extraction OR 2.64 (1.25-5.54), gestation > 40 weeks OR 3.18 (2.35-4.29), and mediolateral episiotomy OR 5.0 (2.64-9.44) were associated with these injuries. In addition, compared with women who had no injuries, sphincter injuries were more common with higher birthweight (3.51 vs 3.17 kg, p < 0.01), larger head circumference (34.3 vs 33.3 cm, p < 0.01), and longer second stage of labor (76 vs 51 min, p < 0.01). Multiple logistic regression revealed higher birthweight and mediolateral episiotomy OR 4.04 (1.71-9.56) as independent risk factors. Episiotomies angled closer to the midline were significantly associated with such injuries (26 vs 37 degrees, p = 0.01). No midwife and only 13 (22%) doctors performed truly mediolateral episiotomies. CONCLUSIONS: Mediolateral episiotomy is an independent risk factor for anal sphincter injuries. Although a liberal policy of mediolateral episiotomy does not appear to reduce the risk of such injuries, it may be related to inappropriate technique. A concerted approach to educate trainees in appropriate episiotomy technique and identification of sphincter injuries is imperative to enable reexamination of the true merits or disadvantages of mediolateral episiotomy.

Occult anal sphincter injuries--myth or reality?

OBJECTIVES: To establish the true prevalence of clinically recognisable and occult obstetric anal sphincter injuries (OASIS). DESIGN: Prospective interventional study. SETTING: Busy district general hospital. SAMPLE: Two hundred and fifty-four women having their first vaginal delivery over a 12-month period were invited. Two hundred and forty-one (95%) participated and 208 (86%) attended follow up. METHODS: Women had a clinical examination at delivery by the accoucheur and repeated by an experienced research fellow immediately after delivery. All identified OASIS were verified and repaired by the duty specialist registrar or consultant. Endoanal ultrasound was performed immediately postpartum prior to suturing and repeated seven weeks later. MAIN OUTCOME MEASURES: Prevalence of recognised and occult anal sphincter injuries. RESULTS: Fifty-nine (24.5%) women sustained OASIS. The prevalence of OASIS increased significantly from 11% to 24.5% when women were re-examined. Of these, 30 occurred in deliveries by midwives who missed 26 (87%) and 29 following deliveries by doctors who missed 8 (28%) injuries. All clinically apparent OASIS were also identified on endoanal ultrasound. In addition, three (1.2%) women had an occult anal sphincter injury. Two of these occult sphincter injuries were isolated to the internal anal sphincter (IAS) and would not usually be clinically detectable. CONCLUSIONS: OASIS occur more frequently than previously reported. Many remain undiagnosed and are subsequently classified as occult when identified on anal endosonography. Genuine occult injuries are rare. Training in perineal anatomy and recognition of OASIS needs to be enhanced in order to increase detection of OASIS and minimise the risk of consequent anal incontinence.

Are mediolateral episiotomies actually mediolateral?

This study investigated potential differences in the cutting of mediolateral episiotomy between doctors and midwives. Depth, length, distance from midline and shortest distance from the midpoint of the anal canal to the episiotomy were measured in a sample of primigravid women. The angle subtended from the sagittal or parasagittal plane was calculated. Two hundred and forty-one women participated of whom 98 (41%) had a mediolateral episiotomy. Doctors performed episiotomies that were significantly deeper, longer and more obtuse than those by midwives. No midwife and only 13 (22%) doctors performed truly mediolateral episiotomies. It appears that the majority of episiotomies are not truly mediolateral but closer to the midline. More focused training in mediolateral episiotomy technique is required.