Journal of Obstetrics and Gynaecology
ISSN: 0144-3615 (Print) 1364-6893 (Online) Journal homepage: http://www.tandfonline.com/loi/ijog20
Management of obstetric anal sphincter injuries (OASIS) in subsequent pregnancy C. Evans, R. Archer, A. Forrest & J. Barrington To cite this article: C. Evans, R. Archer, A. Forrest & J. Barrington (2014) Management of obstetric anal sphincter injuries (OASIS) in subsequent pregnancy, Journal of Obstetrics and Gynaecology, 34:6, 486-488 To link to this article: http://dx.doi.org/10.3109/01443615.2014.911835
Published online: 06 May 2014.
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Date: 14 November 2015, At: 06:32
Journal of Obstetrics and Gynaecology, August 2014; 34: 486–488 © 2014 Informa UK, Ltd. ISSN 0144-3615 print/ISSN 1364-6893 online DOI: 10.3109/01443615.2014.911835
OBSTETRICS
Management of obstetric anal sphincter injuries (OASIS) in subsequent pregnancy C. Evans, R. Archer, A. Forrest & J. Barrington
Downloaded by [University of California, San Diego] at 06:32 14 November 2015
Department of Obstetrics and Gynaecology, Torbay Hospital, Torquay, UK
Obstetric anal sphincter injuries (OASIS) are common and may greatly affect a patient ’s quality of life. There is very little information regarding optimum management in future pregnancies. Based upon anecdotal experience, this study describes the recommendations of a cohort of consultant obstetricians in the UK, in this clinical situation. There is limited adherence to the available national guidelines due to the absence of available equipment and expertise to perform endo-anal ultrasound and manometry. Elective episiotomy is still recommended by a small number of obstetricians but the majority of patients are routinely followed-up. Caesarean section is only advised for asymptomatic patients with a previous stage 4 tear, and for any symptomatic patient with a previous stage 3 or 4 tear, irrespective of subgrade. A request for elective caesarean section is likely to be granted, irrespective of OASIS grade. The use of postpartum endoanal ultrasound would help identify those women in whom a further vaginal delivery is unlikely to exacerbate any symptoms of faecal incontinence. Keywords: Endo-anal, faecal incontinence, intrapartum care, OASIS
Introduction Obstetric anal sphincter injuries (OASIS) are common, affect approximately 1% of all vaginal deliveries (RCOG 2007) (Byrd et al. 2005) and are the most common cause of faecal incontinence in women (Dudding et al. 2008). The incidence of faecal incontinence 10 years following OASIS is 53% compared with 19% following uncomplicated vaginal birth (Samarasekara et al. 2008). With greater emphasis on reporting and as babies increase in size and birth weight, this figure is likely to increase. The consequences of an unrecognised or poorly repaired OASIS injury include anal incontinence to faeces or flatus or faecal urgency that may have a major impact on quality of life, self-esteem, confidence and also social interaction. It is therefore, imperative that these injuries are repaired by appropriately trained surgeons. However, despite adequate anatomical reconstruction, approximately 40% of women will have functional weakness and become symptomatic (Sultan and Thakar 2007), usually associated with persistent anal sphincter defects (Roos et al. 2010), and a dilemma exists as to what is the optimum management in future pregnancies. The Royal College of Obstetricians and Gynaecologists (RCOG) in the UK has produced guidelines that outlines what advice should be given
to women with previous OASIS concerning future pregnancies and mode of delivery (RCOG 2007). This guideline advises that all women who sustain an OASIS in a previous pregnancy should be counselled about the risk of developing anal incontinence or worsening symptoms with subsequent vaginal delivery and should be advised that there is no evidence to suggest the role of prophylactic episiotomy in subsequent pregnancy. All women who are symptomatic or have abnormal endo-anal ultrasonography ⫾ manometry should have the option of an elective caesarean birth. However, all these recommendations are Evidence Level 4 or ‘best practice’, based upon the clinical experience of the guideline development group, since there is a lack of systemic reviews or randomised controlled trials to suggest the best mode of delivery after OASIS (Scheer et al. 2009). It is known that the incidence of OASIS increases 3–6-fold following a previous tear (Lowder et al. 2007) and that between 17% and 24% of women will develop increased faecal symptoms after a second vaginal delivery (Fynes et al. 1999). The RCOG also recommends that all women should be followed up 6–12 weeks’ postpartum by a Consultant in obstetrics and gynaecology, preferably in a dedicated perineal clinic which has access to endo-anal ultrasonography and anal manometry to aid the decision on mode of future deliveries (Sultan and Thakar 2002). This study was therefore carried out to ascertain whether these recommendations are carried out by a body of Consultants in obstetrics and gynaecology in the UK, whether these recommended tests are readily available and if a request for elective caesarean section would be granted. We also investigated subdivisions of stage III OASIS injuries, since most recommendations consider higher degrees of OASIS injuries as a whole. We also attempted to ascertain if advice differed as to whether the patient was symptomatic or asymptomatic of any bothersome or troublesome symptoms, such as incontinence of flatus or stool.
Methods A questionnaire was sent out to 625 Consultant Obstetricians and Gynaecologists practicing in the South of England and Wales. An OASIS injury was classified into stages, as described by Sultan and adopted by The International Consultation on Incontinence and by the RCOG (Sultan 1999). A 3rd-degree tear is defined as partial or complete disruption of the anal sphincter muscles, which may involve either or both the external (EAS) and internal anal sphincter (IAS) muscles (Table I). A 4th-degree tear is defined as a disruption of the anal sphincter muscles with a breach of
Correspondence: J. Barrington, Department of Obstetrics and Gynaecology, Torbay Hospital, Torquay TQ2 7AA, UK. E-mail: [email protected]
Management of obstetric anal sphincter injuries (OASIS) in subsequent pregnancy 487 Table I. Classification of perineal and anal sphincter trauma. 1st degree 2nd degree 3rd degree
4th degree
Injury to perineal skin only Injury to perineum involving perineal muscles but not involving the anal sphincter Injury to perineum involving the anal sphincter complex: A: Less than 50% of EAS thickness torn B: More than 50% of EAS thickness torn C: Both EAS and IAS torn Injury to perineum involving the anal sphincter complex (EAS and IAS) and anal epithelium
Downloaded by [University of California, San Diego] at 06:32 14 November 2015
the rectal mucosa. The same questions were also asked of stage 1 and 2 perineal injury, to compare results from previous studies to ensure the results were standardised.
Results A total of 401 replies (64%) were received: 77% of respondents routinely followed-up with women with OASIS injuries and 76% of these routinely counsel about the risks of developing anal incontinence at this time (Figure 1). However, only 16% routinely perform postpartum endo-anal ultrasonography and an even lower number (8%) carry out anal manometry. The results with regard to advising a future caesarean section are shown in Figure 2. For asymptomatic women most respondents would advise vaginal delivery even for previous OASIS high grade 3C,
and it is only for asymptomatic previous grade 4 tears that a comparable number would advise elective caesarean section. However, symptomatic women with any previous OASIS grade 3 or 4 would be most likely to be advised to have an elective caesarean section. The results with regard to agreeing to a request for elective caesarean section are shown in Figure 3. It would appear that a request for elective caesarean section for any previous OASIS grade 3 and 4 would likely be granted. Despite the RCOG recommendations, a small proportion of women are still advised to have an elective episiotomy, as shown in Figure 4.
Discussion This study has shown that, even in developed countries, women with previous OASIS are not being optimally managed with informed choice in subsequent pregnancies with regard to mode of delivery. All women should be offered a follow-up appointment and those units that do not offer this should be encouraged to do so. In addition, the use of elective episiotomy should be discouraged. Ideally, all women should be offered endo-anal ultrasound, which is the current ‘gold standard’ but it is apparent that few obstetric units possess such equipment and expertise. Anal manometry has been shown to be superior to digital clinical assessment, and using specified cut-off values, women may be either reassured or identified as requiring further assessment by endo-anal ultrasound and referral to tertiary centres (Roos et al. 2012). If no compromise of anal sphincter function is identified,
Figure 1. Frequency of routine follow-up and counselling following OASIS and availability of endo-anal ultrasound and anal manometry.
Figure 2. Advise caesarean section following previous OASIS.
Downloaded by [University of California, San Diego] at 06:32 14 November 2015
488
C. Evans et al.
Figure 3. Agree to caesarean section following previous OASIS.
Figure 4. Advise episiotomy following previous OASIS.
those women may be reassured that a further vaginal delivery is not associated with any significant deterioration in function or quality of life. The National Institute of Clinical Excellence (NICE) in the UK has recommended that a request for an elective caesarean section may be granted so long as a discussion regarding the pros and cons has taken place and there has been an offer of support, including perinatal mental health support for anxiety (NICE 2012). Therefore, any request following previous OASIS should be granted. However, for the majority of obstetric units in this sample, the recommendation of mode of delivery is based upon anecdotal experience. This study has shown what a cohort of peers might recommend if faced with a comparable situation where appropriate investigations are not available to facilitate a clinical decision. Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
References Byrd LM, Hobbiss J, Tasker M. 2005. Is it possible to predict or prevent third degree tears? Colorectal Disease 7:311–318. Dudding TC, Valzey CJ, Kamm MA. 2008. Obstetric anal sphincter injury: incidence, risk factors and management. Annals of Surgery 247:224–227.
Fynes M, Donnelly V, Behan M, O’Connell PR, O’Herlihy C. 1999. The effect of second delivery on anal sphincter function and faecal incontinence: a prospective study. Lancet 354:983–986. Lowder JL, Burrows LJ, Krohn MA, Weber AM. 2007. Risk factors for primary and subsequent anal sphincter lacerations: a comparison of cohorts by parity and prior mode of delivery. American Journal of Obstetrics and Gynecology 197:688–689. NICE. 2012. Clinical guideline 132. Caesarean section. London: NICE. p 1–57. RCOG. 2007. Green-top guideline number 29: the management of third and fourth degree perineal tears. London: RCOG. p 1–11. Roos AM, Abdool Z, Thakar R, Sultan AH. 2012. Predicting anal sphincter defects: the value of clinical examination and manometry. International Urogynecology Journal 23:755–763. Roos AM, Sultan AH, Thakar R. 2010. Outcome of primary repair of obstetric anal sphincter injuries (OASIS) – does the grade of tear matter? Ultrasound in Obstetrics and Gynecology 36:368–374. Samarasekara DN, Bekhit MT, Wright Y, Lowndes RH, Stanley KP, Preston P et al. 2008. Long-term anal continence and quality of life following postpartum anal sphincter injury. Colorectal Disease 10:793–799. Scheer I, Thaker R, Sultan AH. 2009. Mode of delivery after previous obstetric anal sphincter injuries (OASIS) – a reappraisal? International Urogynecology Journal and Pelvic Floor Dysfunction 20:1095–1101. Sultan AH, Thakar R. 2002. Lower genital tract and anal sphincter trauma. Best Practice and Research Clinical Obstetrics and Gynaecology 16:99–115. Sultan AH, Thakar R. 2007. Third and fourth degree tears. In: Sultan AH, Thakar R, Fenner DE, editors. Perineal and anal sphincter trauma. London: Springer. p 35–51. Sultan AH. 1999. Obstetric perineal injury and anal incontinence. Clinical Risk 5:193–196.
ISSN: 0144-3615 (Print) 1364-6893 (Online) Journal homepage: http://www.tandfonline.com/loi/ijog20
Management of obstetric anal sphincter injuries (OASIS) in subsequent pregnancy C. Evans, R. Archer, A. Forrest & J. Barrington To cite this article: C. Evans, R. Archer, A. Forrest & J. Barrington (2014) Management of obstetric anal sphincter injuries (OASIS) in subsequent pregnancy, Journal of Obstetrics and Gynaecology, 34:6, 486-488 To link to this article: http://dx.doi.org/10.3109/01443615.2014.911835
Published online: 06 May 2014.
Submit your article to this journal
Article views: 98
View related articles
View Crossmark data
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ijog20 Download by: [University of California, San Diego]
Date: 14 November 2015, At: 06:32
Journal of Obstetrics and Gynaecology, August 2014; 34: 486–488 © 2014 Informa UK, Ltd. ISSN 0144-3615 print/ISSN 1364-6893 online DOI: 10.3109/01443615.2014.911835
OBSTETRICS
Management of obstetric anal sphincter injuries (OASIS) in subsequent pregnancy C. Evans, R. Archer, A. Forrest & J. Barrington
Downloaded by [University of California, San Diego] at 06:32 14 November 2015
Department of Obstetrics and Gynaecology, Torbay Hospital, Torquay, UK
Obstetric anal sphincter injuries (OASIS) are common and may greatly affect a patient ’s quality of life. There is very little information regarding optimum management in future pregnancies. Based upon anecdotal experience, this study describes the recommendations of a cohort of consultant obstetricians in the UK, in this clinical situation. There is limited adherence to the available national guidelines due to the absence of available equipment and expertise to perform endo-anal ultrasound and manometry. Elective episiotomy is still recommended by a small number of obstetricians but the majority of patients are routinely followed-up. Caesarean section is only advised for asymptomatic patients with a previous stage 4 tear, and for any symptomatic patient with a previous stage 3 or 4 tear, irrespective of subgrade. A request for elective caesarean section is likely to be granted, irrespective of OASIS grade. The use of postpartum endoanal ultrasound would help identify those women in whom a further vaginal delivery is unlikely to exacerbate any symptoms of faecal incontinence. Keywords: Endo-anal, faecal incontinence, intrapartum care, OASIS
Introduction Obstetric anal sphincter injuries (OASIS) are common, affect approximately 1% of all vaginal deliveries (RCOG 2007) (Byrd et al. 2005) and are the most common cause of faecal incontinence in women (Dudding et al. 2008). The incidence of faecal incontinence 10 years following OASIS is 53% compared with 19% following uncomplicated vaginal birth (Samarasekara et al. 2008). With greater emphasis on reporting and as babies increase in size and birth weight, this figure is likely to increase. The consequences of an unrecognised or poorly repaired OASIS injury include anal incontinence to faeces or flatus or faecal urgency that may have a major impact on quality of life, self-esteem, confidence and also social interaction. It is therefore, imperative that these injuries are repaired by appropriately trained surgeons. However, despite adequate anatomical reconstruction, approximately 40% of women will have functional weakness and become symptomatic (Sultan and Thakar 2007), usually associated with persistent anal sphincter defects (Roos et al. 2010), and a dilemma exists as to what is the optimum management in future pregnancies. The Royal College of Obstetricians and Gynaecologists (RCOG) in the UK has produced guidelines that outlines what advice should be given
to women with previous OASIS concerning future pregnancies and mode of delivery (RCOG 2007). This guideline advises that all women who sustain an OASIS in a previous pregnancy should be counselled about the risk of developing anal incontinence or worsening symptoms with subsequent vaginal delivery and should be advised that there is no evidence to suggest the role of prophylactic episiotomy in subsequent pregnancy. All women who are symptomatic or have abnormal endo-anal ultrasonography ⫾ manometry should have the option of an elective caesarean birth. However, all these recommendations are Evidence Level 4 or ‘best practice’, based upon the clinical experience of the guideline development group, since there is a lack of systemic reviews or randomised controlled trials to suggest the best mode of delivery after OASIS (Scheer et al. 2009). It is known that the incidence of OASIS increases 3–6-fold following a previous tear (Lowder et al. 2007) and that between 17% and 24% of women will develop increased faecal symptoms after a second vaginal delivery (Fynes et al. 1999). The RCOG also recommends that all women should be followed up 6–12 weeks’ postpartum by a Consultant in obstetrics and gynaecology, preferably in a dedicated perineal clinic which has access to endo-anal ultrasonography and anal manometry to aid the decision on mode of future deliveries (Sultan and Thakar 2002). This study was therefore carried out to ascertain whether these recommendations are carried out by a body of Consultants in obstetrics and gynaecology in the UK, whether these recommended tests are readily available and if a request for elective caesarean section would be granted. We also investigated subdivisions of stage III OASIS injuries, since most recommendations consider higher degrees of OASIS injuries as a whole. We also attempted to ascertain if advice differed as to whether the patient was symptomatic or asymptomatic of any bothersome or troublesome symptoms, such as incontinence of flatus or stool.
Methods A questionnaire was sent out to 625 Consultant Obstetricians and Gynaecologists practicing in the South of England and Wales. An OASIS injury was classified into stages, as described by Sultan and adopted by The International Consultation on Incontinence and by the RCOG (Sultan 1999). A 3rd-degree tear is defined as partial or complete disruption of the anal sphincter muscles, which may involve either or both the external (EAS) and internal anal sphincter (IAS) muscles (Table I). A 4th-degree tear is defined as a disruption of the anal sphincter muscles with a breach of
Correspondence: J. Barrington, Department of Obstetrics and Gynaecology, Torbay Hospital, Torquay TQ2 7AA, UK. E-mail: [email protected]
Management of obstetric anal sphincter injuries (OASIS) in subsequent pregnancy 487 Table I. Classification of perineal and anal sphincter trauma. 1st degree 2nd degree 3rd degree
4th degree
Injury to perineal skin only Injury to perineum involving perineal muscles but not involving the anal sphincter Injury to perineum involving the anal sphincter complex: A: Less than 50% of EAS thickness torn B: More than 50% of EAS thickness torn C: Both EAS and IAS torn Injury to perineum involving the anal sphincter complex (EAS and IAS) and anal epithelium
Downloaded by [University of California, San Diego] at 06:32 14 November 2015
the rectal mucosa. The same questions were also asked of stage 1 and 2 perineal injury, to compare results from previous studies to ensure the results were standardised.
Results A total of 401 replies (64%) were received: 77% of respondents routinely followed-up with women with OASIS injuries and 76% of these routinely counsel about the risks of developing anal incontinence at this time (Figure 1). However, only 16% routinely perform postpartum endo-anal ultrasonography and an even lower number (8%) carry out anal manometry. The results with regard to advising a future caesarean section are shown in Figure 2. For asymptomatic women most respondents would advise vaginal delivery even for previous OASIS high grade 3C,
and it is only for asymptomatic previous grade 4 tears that a comparable number would advise elective caesarean section. However, symptomatic women with any previous OASIS grade 3 or 4 would be most likely to be advised to have an elective caesarean section. The results with regard to agreeing to a request for elective caesarean section are shown in Figure 3. It would appear that a request for elective caesarean section for any previous OASIS grade 3 and 4 would likely be granted. Despite the RCOG recommendations, a small proportion of women are still advised to have an elective episiotomy, as shown in Figure 4.
Discussion This study has shown that, even in developed countries, women with previous OASIS are not being optimally managed with informed choice in subsequent pregnancies with regard to mode of delivery. All women should be offered a follow-up appointment and those units that do not offer this should be encouraged to do so. In addition, the use of elective episiotomy should be discouraged. Ideally, all women should be offered endo-anal ultrasound, which is the current ‘gold standard’ but it is apparent that few obstetric units possess such equipment and expertise. Anal manometry has been shown to be superior to digital clinical assessment, and using specified cut-off values, women may be either reassured or identified as requiring further assessment by endo-anal ultrasound and referral to tertiary centres (Roos et al. 2012). If no compromise of anal sphincter function is identified,
Figure 1. Frequency of routine follow-up and counselling following OASIS and availability of endo-anal ultrasound and anal manometry.
Figure 2. Advise caesarean section following previous OASIS.
Downloaded by [University of California, San Diego] at 06:32 14 November 2015
488
C. Evans et al.
Figure 3. Agree to caesarean section following previous OASIS.
Figure 4. Advise episiotomy following previous OASIS.
those women may be reassured that a further vaginal delivery is not associated with any significant deterioration in function or quality of life. The National Institute of Clinical Excellence (NICE) in the UK has recommended that a request for an elective caesarean section may be granted so long as a discussion regarding the pros and cons has taken place and there has been an offer of support, including perinatal mental health support for anxiety (NICE 2012). Therefore, any request following previous OASIS should be granted. However, for the majority of obstetric units in this sample, the recommendation of mode of delivery is based upon anecdotal experience. This study has shown what a cohort of peers might recommend if faced with a comparable situation where appropriate investigations are not available to facilitate a clinical decision. Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
References Byrd LM, Hobbiss J, Tasker M. 2005. Is it possible to predict or prevent third degree tears? Colorectal Disease 7:311–318. Dudding TC, Valzey CJ, Kamm MA. 2008. Obstetric anal sphincter injury: incidence, risk factors and management. Annals of Surgery 247:224–227.
Fynes M, Donnelly V, Behan M, O’Connell PR, O’Herlihy C. 1999. The effect of second delivery on anal sphincter function and faecal incontinence: a prospective study. Lancet 354:983–986. Lowder JL, Burrows LJ, Krohn MA, Weber AM. 2007. Risk factors for primary and subsequent anal sphincter lacerations: a comparison of cohorts by parity and prior mode of delivery. American Journal of Obstetrics and Gynecology 197:688–689. NICE. 2012. Clinical guideline 132. Caesarean section. London: NICE. p 1–57. RCOG. 2007. Green-top guideline number 29: the management of third and fourth degree perineal tears. London: RCOG. p 1–11. Roos AM, Abdool Z, Thakar R, Sultan AH. 2012. Predicting anal sphincter defects: the value of clinical examination and manometry. International Urogynecology Journal 23:755–763. Roos AM, Sultan AH, Thakar R. 2010. Outcome of primary repair of obstetric anal sphincter injuries (OASIS) – does the grade of tear matter? Ultrasound in Obstetrics and Gynecology 36:368–374. Samarasekara DN, Bekhit MT, Wright Y, Lowndes RH, Stanley KP, Preston P et al. 2008. Long-term anal continence and quality of life following postpartum anal sphincter injury. Colorectal Disease 10:793–799. Scheer I, Thaker R, Sultan AH. 2009. Mode of delivery after previous obstetric anal sphincter injuries (OASIS) – a reappraisal? International Urogynecology Journal and Pelvic Floor Dysfunction 20:1095–1101. Sultan AH, Thakar R. 2002. Lower genital tract and anal sphincter trauma. Best Practice and Research Clinical Obstetrics and Gynaecology 16:99–115. Sultan AH, Thakar R. 2007. Third and fourth degree tears. In: Sultan AH, Thakar R, Fenner DE, editors. Perineal and anal sphincter trauma. London: Springer. p 35–51. Sultan AH. 1999. Obstetric perineal injury and anal incontinence. Clinical Risk 5:193–196.
