Affections of cecum, colon & rectum (Veterinary)

Therapeutic approach towards large intestine diseases correction

1. Affections of Cecum, Colon & Rectum By: Girjesh Upmanyu

2. Key Words Celiotomy/ Laparotomy : incision into the abdominal cavity. Typhlotomy: an incision into the cecum. Enterotomy : an incision into the intestine. Anastmosis : surgical connection between two structures, usually that is created between tubular structures.

3. Various approaches to abdomen & structures encountered Ventral midline celiotomy- Linea alba Peritonium Ventral Paramedian approach- External sheath of rectus abdominus muscle Internal rectus sheath Peritonium Flank approach- External abdominal oblique muscle Internal abdominal oblique muscle Transversus abdominus muscle Peritonium

4. Layers of Intestine Mucosa Submucosa Muscularis propria 1) Circular layer: squeezing action 2) Longitudinal layer: propelling action Subserosa Serosa

5. CECUM

6. Anatomy (Equine) The cecum is positioned between the small intestine and the large colon and located primarily on the right side of the abdomen. It is a large cul-de-sac with an average length of 1.25 m and an average capacity of 30 L. It has a comma shaped appearance and is divided into three parts—the base, body, and apex. The base, which is the most dorsal part, is positioned in the right iliac and sublumbar region. It has a greater curvature dorsally and lesser curvature ventrally. It extends craniad to the 14 th or 15 th rib, forming a blind end pointing ventrally.

7. Contd …. The body of the cecum travels cranioventrally from the cecal base & caudally, it lies against the right flank. The cecal base is attached dorsally to the ventral surface of the right kidney, to the right lobe of the pancreas, and to a part of the abdominal wall caudal to these structures. The cecal base is attached medially to the transverse colon and the root of the mesentery. a, ileum b, base of cecum c, body of cecum d, apex of cecum e, lateral teniae f, proximal part of right ventral colon.

8. Cecal Impaction Etiopathogenesis: The etiology of cecal impaction is most likely multifactorial . include poor dentition, feeding of poor-quality roughage, decreased water intake, parturition, and parasite-induced thromboembolism . Tapeworms ( Anoplocephala perfoliata ) located at the cecocolic orifice have been associated with cecal impaction. Some of the impactions may be related to a motility dysfunction. During and after general anesthesia , motility of the gastrointestinal tract is disrupted, with the cecum taking the longest time to return to normal function. Use of nonsteroidal anti-inflammatory drugs (NSAIDs) and lack of exercise have also been associated with the development of cecal impaction. The most common pathologic condition of the cecum is cecal impaction, and it accounts for between 40% and 55% of cecal disease, 5% of all intestinal impactions, and 2% of all referral colics .

9. Clinical Signs horses with cecal impaction show only mild signs of pain , with intermittent periods of increased severity, that may continue for several days to several weeks. The mild signs of colic include lying down, looking at the flank, decreased appetite, and depression. HR -normal to slightly elevated. Borborygmi are decreased, and feces may be soft with decreased production. Horses may be presented with cecal rupture with no history of significant abdominal pain.

10. Diagnosis The diagnosis is confirmed by rectal palpation in most cases. The first indication of a cecal impaction may be increased tension in the ventral cecal band . As the impaction enlarges, the cecal body begins to fill and the sacculations in the cecal body and a rounded cecal base are palpable.

11. Medical Therapy The goal of medical therapy is to soften the ingesta to allow cecal contractions to empty the cecal contents into the right ventral colon. Feed should be withheld and the horse started on intravenous fluid therapy. Oral laxatives by nasogastric tube.-Mineral oil (5 to 10 mL /kg every 12 hours) is commonly used. Magnesium sulfate ( 1 g / kg) is a saline laxative that exerts an osmotic effect, pulling water into the intestinal lumen. Psyllium hydrophilic mucilloid (1.0 kg every 6 to 8 hours) has also been recommended for treatment of cecal impactions. Analgesics such as flunixin meglumine (0.5 to 1.1 mg/kg IV every 12 hours) is used for pain relief.

12. SURGICAL THERAPY Typhlotomy: The preferred surgical approach for a typhlotomy is through a ventral midline celiotomy. The cecum should be manipulated carefully with hands and arms placed around the body of the cecum, lifting the cecal body to allow exteriorization of the apex. An 8-12cm typhlotomy incision is made between the lateral and ventral cecal bands. The size depends on the consistency of the ingesta. A sterile tube is placed in the typhlotomy incision, and warm water is infused to aid in flushing out the cecal contents. Once the cecal contents have been evacuated, the contaminated region around the typhlotomy incision should be thoroughly rinsed with electrolyte solution. The typhlotomy incision is closed with a double-inverting suture pattern or an appositional followed by an inverting pattern using 2-0 absorbable suture material.

13. Cecocolic anastomosis: This technique is performed in addition with Typhlotomy because of the poor response seen in horses with cecal impactions managed by typhlotomy only. In this technique, a cecocolic anastomosis (CCA) is performed to create an alternative route for ingesta to pass from the cecum to the right ventral colon. The cecocolic anastomosis is performed between the lateral and dorsal bands of the cecum and between the lateral and medial free bands of the right ventral colon.

14. Cecocecal or Cecocolic Intussusception Etiopathogenesis: Cecocecal and cecocolic intussusception occur when the cecal apex invaginates into the cecal body (cecocecal) or continues through the cecocolic orifice and enters the large colon (cecocolic). The etiology is unknown, but altered motility has been suggested to play a role. Dietary changes, cecal wall abscess, Salmonella, Eimeria leuckarti , Strongylus vulgaris arteritis , organophosphates, and administration of parasympathomimetic drugs have all been implicated as potential risk factors. Tapeworm infestation is often encountered in horses with cecal intussusception.

15. Clinical Signs In acute, moderate to severe pain requiring immediate surgical intervention. Subacute form (3 to 8 days) characterized by intermittent mild to moderate pain with soft feces or diarrhea. Chronic form (6 to 180 days) characterized by weight loss, scant soft feces, and mild abdominal pain. Fever is common in horses suffering from this problem over a longer period of time.

16. Diagnosis Rectal examination may be unremarkable as the intussuscepted cecal apex may not be palpable. Ultrasonography may aid in making the diagnosis. Often, the diagnosis is made at surgery.

17. Surgical reduction with partial typhlectomy The surgical approach is through a ventral midline celiotomy. During the abdominal exploration, the cecal apex is found to be intussuscepted into the body of the cecum in the case of a cecocecal intussusception, whereas the cecum is “absent” from its normal position (with a palpable mass in the right ventral colon) in the case of a cecocolic intussusception. Manual reduction is attempted first The intussusceptum is frequently vascularly compromised, necessitating a partial typhlectomy. To prepare for the partial typhlectomy, the lateral and medial cecal vessels are double- ligated with 0 absorbable suture. Intestinal clamps are placed proximal to the intended amputation site across the cecum to decrease fecal contamination, and the surgical area is draped off. After sharply resecting the compromised cecal apex and body, the cecum is closed using either an inverting or an appositional pattern, followed by an inverting suture pattern with no. 0 absorbable suture.

18. Cecal amputation through a colotomy Manual reduction of cecocolic intussusceptions is frequently not successful because of edema and adhesion formation. In these cases, reduction of the intussusception should be approached through a colotomy. Cecum intussuscepted into the right ventral colon through the cecocolic orifice

19. Contd …. The large colon should be exteriorized from the abdomen & enterotomy is made on the ventral surface of the right ventral colon centered over or immediately distal to the intussusceptum . A sterile plastic bag or a plastic enterotomy drape can be sutured to the colon before the enterotomy is made to limit contamination during the colostomy. Right ventral colostomy exposing the cecal intussusception. A sterile plastic bag or drape has been sutured to the seromuscular layer of the RVC prior to the colostomy to help contain contamination .

20. Contd …. The medial and lateral aspects of the inverted cecum are blindly ligated with two parallel transfixation sutures to occlude the cecal vessels. The invaginated cecum is then transected and the remaining cecal stump reduced using both gentle traction on the cecal body and pushing the remaining inverted cecum out. The colotomy incision is closed with a two-layer inverting pattern using 2-0 or 0 absorbable suture. Occluding mattress sutures have been placed across the inverted cecum to facilitate removal of as much of the cecum as possible. The intussusception is then amputated through the right ventral colon.

21. Contd …. The now everted cecal stump is subsequently examined for viability. If necessary, further resection of the cecum is performed . The cecum is closed with a double-inverting pattern using no. 0 absorbable suture. If the cecum cannot be reduced after partial resection within the colon, or if the remaining cecal stump is friable and necrotic, the cecal stump is left invaginated within the colon and a cecal bypass procedure is performed. After eversion of the cecal stump, the remaining compromised part of the remaining cecum is amputated.

22. Anatomy (Bovine) The cecum is a large, mobile tube with the apex directed caudally. Cranially, the cecum is continuous with the proximal loop of the ascending colon (PLAC ). The main part of the cecum is situated within the supraomental recess . The cecum is attached dorsally to the PLAC by the short cecocolic fold and ventrally to the ileum by the ileocecal fold. The PLAC extends cranially from the cecum to the level of the 11th rib and then doubles back to the level of the caudal flexure of the duodenum. There, it turns from the right to the left of the mesentery and is continuous with the spiral colon.

23. Cecal dilatation & Torsion Cecal dilatation is distention of the cecum without twist. Rotation of cecum along its long axis is called cecal torsion.

24. ETIOPATHOGENESIS: Diets excessively rich in rumen-resistant starch have been implicated in the development of spontaneous cecal dilatation and dislocation (CDD), as a consequence of increased carbohydrate fermentation in the large intestine.

25. SYMPTOMS AND DIAGNOSIS Drop in milk yield, reduced appetite and amount of feces, and occasionally discrete signs of colic. Ruminal motility and small intestinal peristalsis may be reduced . The right paralumbar fossa is distended ; percussion and auscultation in the right flank are positive. The apex of the cecum reaches the pelvic cavity and can be palpated as a tense dome-shaped hollow organ with a smooth surface. Cecal torsion can be diagnosed through rectal examination. The cecal apex is directed caudad , and the tense ileocecocolonic ligament, which may have pain elicited upon palpation, is identified as a tense structure that spirals around the cecum

26. Mature white Holstein-Friesian cow with cecal dislocation. The distended cecum has resulted in two outlines of distended viscera (arrows) in the right paralumbar fossa .

27. Treatment First medical therapy is indicated if the general condition of the animal is normal or only slightly disturbed, defecation is still present, and rectal examination does not reveal any torsion. Medical treatment consists of intravenous fluid administration supplemented with potassium chloride, purgatives, and NSAIDs as needed. Bethanechol may be administered subcutaneously at 0.07 mg/kg bwt , TID for 2 days If the medical treatment is revealed as unsuccessful within 24 hours after initiation, typhlotomy is indicated. Cecal amputation is indicated only in cases devitalization of the cecal wall.

28. Typhlotomy Surgery is performed through a right flank approach, preferably in the standing animal under local anesthesia . The abdomen is opened through a 25-cm incision that starts dorsally about 8 cm below the lateral processes of the lumbar vertebrae and 8 cm cranial to the tuber coxae . The incision extending slightly oblique in a cranioventral direction parallel to the internal oblique abdominal muscle to explore abdomen thoroughly. Correction of the abnormality.

29. Cecal Intussusception Etiopathogenesis: Calves are more prone to cecal intussusception because adults have a fat-filled mesentery that maintains the relationship of the various segments of the intestine. While Calves’ mesenteric fat is usually minimal, which allows increased mobility of the slings of the intestine. In case of equines altered motility has been suggested to play a role. Dietary changes, cecal wall abscess, Salmonella, Eimeria leuckarti , Strongylus vulgaris arteritis , organophosphates, and administration of parasympathomimetic drugs have all been implicated as potential risk factors.

30. Four different types of IS involving the cecum have been seen. They include cecocecal , cecocolic , ileocecocolic , and ileocecal IS 1) Cecocecal intussusception . 2) Cecocolic intussusception.

31. Contd …. 3) Ileocecocolic intussusception. 4) Ileocecal intussusception.

32. Symptoms and Diagnosis moderate to severe depression, partial to complete anorexia, abdominal distension accentuated in the right flank, and mild signs of abdominal pain. Scant amounts of dark-red feces and mucus strands may be present. Tachycardia and dehydration may be evident. Auscultation performed simultaneous with percussion identifies variable small “pings” and superficial ”splashing sounds” of fluid-filled bowel in the right flank. Fever is common in horses suffering from this problem over a longer period of time.

33. Surgical Treatment The calf is restrained in left lateral recumbency and an exploratory celiotomy performed in the right flank under local or general anesthesia . The affected bowel is exteriorized, and the IS manually reduced if possible, if not then typhlotomy is performed.

34. COLON

35. Anatomy (Equine) The equine ascending colon begins at the cecocolic orifice and ends in the transverse colon. It measures approximately 3 to 3.7 m in length and has a capacity of 50 to 60 L. It is composed of the ventral and dorsal areas of the colon, which are connected by a short mesentery. In situ, the large colon is further folded such that four segments are designated as the right and left ventral colon and the right and left dorsal colon. The transition from the left and right ventral colons forms the sternal flexure, and the transition from the left and right dorsal colons forms the diaphragmatic flexure.

36. Contd …. The transverse colon is the continuation of the right dorsal colon. It begins at the level of the 17th or 18th thoracic vertebra where the right dorsal colon narrows significantly in diameter as it turns medially. The transverse colon is short and passes from right to left, cranial to the cranial mesenteric artery. It is connected dorsally to the pancreas, to the dorsal aspect of the abdominal cavity, and by a short transverse mesocolon to the root of the mesentery. To the left of the root of the mesentery, the transverse colon continues as the descending colon, also known as the small colon. The small colon occupies the left caudodorsal quadrant of the abdominal cavity. The small colon is approximately 3.5 m long and maintains a 7-10cm width throughout its entire length.

37. Large Colon Impaction Etiology: Risk factors include crib-biting or windsucking , increasing number of hours spent in a stable, recent change in the regular exercise program, absence of administration of ivermectin or moxidectin anthelmintic in the previous 12months, and a history of travel in the previous 24 hours. Additional factors include history of previous colic, recent (less than 4 weeks) lameness, and increasing time since last dental care.

38. Diagnosis The most common location for large colon impaction is the pelvic flexure, followed by the right dorsal and transverse colon. On physical examination, horses typically show mild to moderate abdominal pain, decreased or absent intestinal sounds, decreased or absent fecal production, and occasionally mild to moderate abdominal distention . Rectal palpation is diagnostic in cases of pelvic flexure impaction. However, impactions of the right dorsal and transverse colon can be difficult to palpate in adult horses.

39. Medical Therapy Medical treatment of large colon impaction includes fluid therapy, analgesics, cathartics, and withholding of feed until the impaction is resolved.

40. Sand Impaction Etiology: Accumulation of sand in the equine large colon can result in variable signs, including colic, diarrhea, weight loss, and poor performance. Risk factors for sand impaction include insufficient roughage in the diet, access to sand, and mineral composition of the soil.

41. Diagnosis Horses with sand impaction manifest signs similar to those of large colon impaction, unless a concurrent large colon displacement or torsion is present. clinical signs include mild to moderate abdominal pain, reduced fecal production, and decreased intestinal sounds. The sound of sand may be auscultated when the ventral abdomen is auscultated behind the xyphoid . Diagnostic procedures that are used to detect the presence of sand include observation of sand in the feces, sand obtained or palpated during abdominocentesis , abdominal auscultation, rectal palpation of a sand-filled viscus , abdominal radiography, and abdominal ultrasonography . Lateral radiographic projection of the ventral abdomen of a horse showing accumulation of sand in the ventral colon (arrows).

42. Medical Therapy Medical treatment of sand impaction includes removing the horse from access to sand, rehydration by intravenous or oral methods, and the use of laxatives. Mineral oil is usually not effective, as it will pass around the sand. Magnesium sulfate or psyllium is used to promote evacuation of sand.

43. Large Colon Enterotomy The most commonly performed procedure in the large colon is pelvic flexure enterotomy for evacuation of the large colon. Pelvic flexure enterotomy and large colon evacuation: For this procedure, the large colon is exteriorized between the hind legs. In anticipation of colonic evacuation, a lavage system should be established. A full-thickness, 8- to 12-cm incision is made on the antimesenteric border of the pelvic flexure. One hose is inserted and gently advanced into the colon, while the other is used to continuously lavage the serosal surface to prevent fecal contamination. With sterile technique, feed the hose into the colon and massage its contents. Closure of pelvic flexure enterotomies is performed using 2-0 absorbable suture material in two layers: a simple-continuous seromuscular layer followed by a Lembert or a Cushing pattern. The colon is rinsed thoroughly with sterile saline and replaced in the abdomen.

44. Enterolithiasis Etiology: Risk factors include geographic location, breed predisposition (e.g., Arabians and Arabian crosses, Morgans , American Saddlebreds , donkeys, and miniature horses), feeding alfalfa hay, and less than 50% of time spent outdoors.

45. Diagnosis Enterolithiasis can result in acute severe luminal obstruction or cause intermittent mild signs of colic, depending on the location and size of the enterolith . Those in the large colon are usually localized in the right dorsal colon and cause mild signs of intestinal discomfort. Once they migrate into the transverse or small colon, signs of acute luminal obstruction develop, with progressive abdominal distention . Although this condition causes a simple colonic obstruction, transmural pressure necrosis can occur. Rectal palpation may be normal or may reveal large colon distention . Radiographs are a useful diagnostic method for the detection of enteroliths .

46. Foreign Body Obstructions The obstructing objects include rubberized, fencing and nylon tires, rope, disposable plastic sleeves, feed sacks, and cloth material. Clinical signs & Diagnosis: getting up and down, stretching, anorexia, and scant passage of feces, walking backward and dog sitting

47. Surgical Treatment Small colon enterotomy is indicated to remove intraluminal obstruction of the small colon, such as fecal impactions, enteroliths , fecaliths , and foreign bodies. a ventral midline celiotomy is performed to provide access to the small colon. However, in fecalith or foreign body, a flank incision may provide adequate access to the lesion. The preferred location for the enterotomy is a longitudinal incision on the antimesenteric teniae .

48. Contd …. The segment of small colon where the enterotomy is to be performed is exteriorized and draped separately from the abdomen and the rest of the gastrointestinal tract. Intestinal clamps are placed proximal and distal to the enterotomy site to prevent spillage of fecal material during the enterotomy . The incision is made sharply with a #10 scalpel blade. A two layer closure is performed using a full-thickness simple continuous pattern followed by a seromuscular inverting pattern with 2-0 absorbable suture material, taking care to invert a minimal amount of tissue.

49. Anatomy (Bovine) The colon consists of the ascending, transverse, and descending parts. The ascending colon is divided into three sections: proximal loop, spiral colon, and distal loop. The proximal loop of the ascending colon (PLAC) communicates orally with the cecum on the lateral side of the mesenteric root and aborally with the spiral colon on the medial side. The distal loop of the ascending colon represents the communication between the spiral and transverse colon.

50. Contd …. The descending colon courses in a caudal direction and is continuous with the longer peritoneal and shorter retroperitoneal part of the rectum.

51. Obstruction of the Spiral Colon ETIOPATHOGENESIS: Obstruction of the spiral colon is either a consequence of dysmotility , sequelae of cecal dilatation/dislocation, or caused by lesions extrinsic to the bowel. Calves with severe diarrhea may slough their intestinal mucosa. This may result in a fibrinous cast that can obstruct the spiral colon

52. CLINICAL SIGNS AND DIAGNOSIS Reduced milk yield, appetite, and fecal output. Adhesions may be palpated at rectal examination and visualized by ultrasonographic examination through the right paralumbar fossa . abdominal distension, progressive depression, and decreased appetite

53. Surgical Treatment Exploratory celiotomy through a right paralumbar fossa reveals distension oral to the obstruction. The obstruction is felt as a firm object within the lumen of the spiral colon. Afterward enterotomy is made along the longitudinal axis of the affected segment of spiral colon. The intraluminal obstruction is removed and the longitudinal enterotomy is closed.

54. Atresia Coli Intestinal atresia is the complete absence of a portion of the intestinal lumen. Atresia of the colon is most frequently located in the mid spiral loop of the ascending colon. The cause of atresia coli in calves is not well understood and represents a matter of scientific controversy.

55. Surgical Treatment Surgery is performed under local or general anesthesia through the right paralumbar fossa with the calf in left lateral recumbency . Digesta are removed from the intestine proximal to the site of atresia through an enterotomy at the apex of the cecum or through the dissected proximal blind end of the colon. Anastomosis is achieved by a single layer of apposing simple interrupted sutures.

56. RECTUM

57. Anatomy (Equine) The rectum is approximately 30 cm long in an adult horse and extends from the pelvic inlet to the anus. The peritoneal part of the rectum is attached dorsally by the mesorectum , which is a continuation of the mesocolon . The retroperitoneal part of the rectum forms a dilation called the rectal ampulla , which has thick longitudinal muscle bundles

58. RECTAL PROLAPSE (Equine) Etiology: Causes of rectal prolapse are straining from diarrhea, dystocia , intestinal parasitism, colic, proctitis , rectal tumor, and rectal foreign body. The condition is more common in females than in males and may affect any age group

59. Classification In a type I rectal prolapse, only the rectal mucosa and submucosa project through the anus. A type II lesion represents a complete prolapse of the full thickness of all or part of the rectal ampulla . Type I and II prolapses are the most common. In a type III prolapse, a variable amount of small colon intussuscepts into the rectum in addition to a type II Prolapse. In a type IV prolapse, the peritoneal rectum and a variable length of the small colon form an intussusception through the anus. This type of prolapse is seen with dystocia in mares

60. Rectal Prolapse (Bovine) OCCURENCE: Any breed, sex, or age can be affected. however, rectal prolapse occurs most commonly in feedlot cattle from 6 months to 2 years of age. In a type I prolapse, only the rectal mucosa projects through the anus. A type II prolapse is a complete prolapse of all layers of the rectum. In a type III prolapse, a variable amount of descending colon intussuscepts into the rectum in addition to a type II lesion. In a type IV prolapse, variable lengths of the peritoneal rectum and/or descending colon form an intussusception through the anus. Types I and II are much more common than types III and IV.

61. CLINICAL SIGNS AND DIAGNOSIS The usual presentation of a prolapse is a mucosal mass protruding beyond the anus with a variable amount of edema, inflammation, and necrosis. On manual palpation, types I to III are continuous with the mucocutaneous junction of the anus, whereas type IV represents a protrusion with a palpable trench inside the rectum.

62. MANAGEMENT Elimination of predisposing factors Soothing of the irritated mucosa Elimination of straining Resolving the prolapse. For type IV prolapse, celiotomy, resection of the affected tissue, and end-to-end anastomosis would be indicated.

63. REPLACEMENT AND PURSE-STRING SUTURE This technique is indicated for treatment of salvageable rectal prolapses . After caudal epidural anesthesia is performed and the mucosa is cleaned, the edema is reduced by temporary topical application of a hyperosmotic solution, such as a sugar solution. Lidocaine jelly is applied, and the tissue is manipulated back into its normal position. A purse-string suture is applied to the perirectal tissue with 0.2 to 0.5 cm umbilical tape. The rectal opening is tightened to two-to-three fingers’ width to prevent recurrence of the prolapse while allowing passage of fecal material.

64. SUBMUCOSAL RESECTION Submucosal resection is the preferred technique if the prolapsed mucosa is necrotic, ulcerated, or traumatized, but the underlying tissue is healthy.

65. Contd …. A piece of flexible tubing of appropriate diameter is inserted into the lumen of the prolapse and cross-pin fixation performed to control movement of the prolapse during surgery.

66. Contd …. Two circumferential incisions are made through the mucosa on either side of the tissue to be removed. The collar of affected tissue is removed in the healthy submucosal plane by using blunt dissection.

67. Contd …. The mucosa is aligned with four simple interrupted sutures that are placed equidistant around the circumference of the prolapse

68. Contd …. The four quadrants are apposed separately with one simple continuous suture pattern for each quadrant.

69. STAIRSTEP AMPUTATION When the prolapsed tissue is severely damaged, amputation may be the only alternative. A circumferential incision is made just cranial to the necrotic area. All tissues except the inner mucosa are incised.

70. Contd …. With blunt dissection, a plane is created towards the caudal aspect of the prolapse within the inner submucosa between the inner and outer segment.

71. Contd …. The outer segment is pulled forward, and the inner segment amputated 2 to 3cm more distal than the outer segment.

72. Contd …. Suture pattern and material for adaptation of the mucosal layers are identical as described for submucosal resection.

73. Atresia Ani (Et Recti ) fistula formation between the rectum and the reproductive tract, and abnormalities of the urinary tract may accompany atresia ani . In females, the rectum may communicate with the vagina, in males with the urethra or the bladder.

74. CLINICAL SIGNS AND DIAGNOSIS Affected calves show signs within the first day of life because they are unable to pass feces. An exception to this is the affected female with a rectovaginal fistula that passes some feces through the fistula. They exhibit progressive abdominal distention , straining, signs of abdominal pain, depression, and weakness. If only the anus is involved, the rectum usually bulges subcutaneously in the normal region of the anus during straining and when the abdomen is manually compressed.

75. Surgical Treatment For surgical correction, 1 ml of 1% lidocaine solution is injected epidurally , and the hind part of the calf is directed toward the edge of the surgery table in sternal recumbency with the hind feet pulled slightly craniad . After routine aseptic preparation of the surgical field, a 1-cm diameter circular incision is made through the skin and subcutaneous tissue at the site where the anus would normally be located. Careful blunt dissection in a cranial direction is used to identify the rectal pouch, which is gently pulled caudad with a pair of tissue forceps. The rectal pouch is incised, and the rectal mucosa is sutured to the skin using a broken simple continuous or interrupted suture pattern.

76. Thank You