اندیکاسیون سزارین از دیدگاه پروکتولوژیست دکتر رسول عزیزی جراح کولورکتال، دانشیار گروه جراحی دانشکده پزشکی دانشگاه علوم پزشکی ایران مجتمع رسول اکرم، بخش جراحی

Anatomy & physiology of continence introduction The ability to retain a bodily discharge voluntarily”. The word has its origins from the Latin continere or tenere, which means “to hold”. The anorectum is the caudal end of the gastrointestinal tract, and is responsible for fecal continence and defecation. In humans, defecation is a viscero somatic reflex that is often preceded by several attempts to preserve continence

Mechanisms of Continence and Defecation

Risk Factors in Fecal Incontinence Obstetric Events *Sphincteric Injury *Pudental Nerve Injury *Secondary Rectal Sensorimotor Dysfunction

KAMM MA (1994) OBSTETRIC DAMAGE AND FECAL INCONTINENCE. LANCET 344:730 BHARUCHA AE (2003) FECAL INCONTINENCE. GASTROENTEROLOGY 124: There is now clear recognition, supported by a considerable body of evidence, that Obstetric trauma is, by far, the major risk factor for the development of acquired fecal incontinence in women

In a frequently referenced study by Sultan and colleagues in 1993,ultasound at 6 weeks postpartum revealed sphincter injuries in 35% of primiparous women and 44% of multiparous women. Sultan AH, Kamm MA, Hudson CN et al (1993) Anal sphincter disruption during vaginal delivery. N Eng J Med 329:1905–1911

THE PREVALENCE OF SYMPTOMS OF FECAL INCONTINENCE POSTPARTUM IN STUDIES INVOLVING >130 SUBJECTS AND SHOWS THAT GREATER THAN 10% OF WOMEN WILL COMPLAIN OF BOWEL SYMPTOMS IN THE FIRST FEW MONTHS FOLLOWING CHILDBIRTH 1-Chaliha C, Kalia V, Stanton SL et al (1999) Antenata prediction of postpartum urinary and fecal incontinence Obstet Gynecol 94: MacArthur C, Glazener CM, Wilson PD, et al(2001) Obstetric practice and faecal incontinence three months after delivery. BJOG 108: MacArthur C, Bick DE, Keighley MR (1997) Faecal incontinence after childbirth. Br J Obstet Gynaeco104:46-50 –

Oberwalder and colleagues performed a meta-analysis of 717 vaginal deliveries has three notable results: First, the incidence of anal sphincter defects in primiparous women was 26.9%. Second, multiparous women had an 8.5% incidence of new sphincter defects. Third, the calculated probability that postpartum fecal incontinence was due to a sphincter defect was 76.8–82.8%. Oberwalder M, Connor J, Wexner SD (2003) Metaanalysis to determine the incidence of obstetric anal sphincter damage. Br J Surg 90:1333–1337

Episiotomy was at one time believed to be protective to the perineum during childbirth and was used to prevent the occurrence of third- and fourth-degree tears. There is now evidence that episiotomy not only fails to protect the perineum but has been associated with increased tearing and anal sphincter injury 1-Thacker SB, Banta HD (1983) Benefits and risks of episiotomy: an interpretive review of the English language literature. Obstet Gynecol Surv 38:322–338 2-Klein MC, Gauthier RJ, Robbins JM et al (1994) Relationship of episiotomy to perineal trauma and morbidity, sexual dysfunction, and pelvic floor relaxation. Am J Obstet Gynecol 171:591–598

Many papers have been published regarding obstetric lesions as they relate to incontinence. However, it is difficult to accurately quantify the prevalence of obstetric injury and its effect on the incidence of incontinence.

In addition to direct trauma to the sphincter muscle, pudendal neuropathy is another consequence of vaginal delivery, which contributes to fecal incontinence. The pudendal nerve is believed to be damaged by the fetal head, which compresses the nerve, causing ischemia or stretching its branches repeated pregnancies and deliveries add to the damage, the neuropathy progresses as the woman ages, and the worsening over time causes significant fecal incontinence that presents between 50 and 60 years of age

Cesarean section has been advocated as an option to protect the pelvic floor and reduce the incidence of postpartum fecal incontinence; however, this issue is controversial. Cesarean section performed after cervical dilation, especially if performed late in the second stage of labor, is not entirely protective against direct sphincter trauma or pudendal neuropathy At this time, the best practice seems to be evaluation of a woman’s risk factors, informed consent regarding her risk of pelvic floor trauma from vaginal delivery, proper recognition of injury at the time of delivery, and effective postpartum evaluation

Nelson et al. covering 15 studies encompassing 3,010 Caesarean section and 11,440 vaginal deliveries showed no difference between the rate of either fecal or flatus incontinence between the two different modes of delivery. The implication of both of these studies is that it is pregnancy itself, perhaps in relation to connective tissue properties or perhaps an inherited susceptibility, that can lead to pelvic floor disorders. Nelson RL, Westercamp M, Furner SE (2006)A systematic review of the efficacy of Cesarean section in the preservation of anal continence. Dis Colon Rectum49:

Risk Factors Anorectal Anomalies Spina Bifida Isolated Sacral Agenesis Hirschprung’s Disease Cerebrovascular Accidents Parkinson's Disease Multiple Sclerosis Spinal Cord Injury Diabetes Mellitus Ageing Inflammatory Bowel Disease Irritable Bowel Syndrome Anal Surgery Rectal Resection Rectal Evacuatory Disorder Rectal prolapse