Bovine diseases of the cecum, large colon and descending colon Hawkins (1).pptx

Bovine diseases of the cecum, large colon, and descending colon Jan F. Hawkins, DVM, DACVS Professor of Large Animal Surgery Segmental volvulus of the jejunoileum Involves distal most aspect of the jejunoileummesenteric flange Range from 180-360 degrees mesenteric fat may “cushion” vessels from stra...

Bovine diseases of the cecum, large colon, and descending colon Jan F. Hawkins, DVM, DACVS Professor of Large Animal Surgery Segmental volvulus of the jejunoileum Involves distal most aspect of the jejunoileummesenteric flange Range from 180-360 degrees mesenteric fat may “cushion” vessels from strangulation strangulation leading to ischemia Occurs in cattle of all ages Pain ranges from kicking at abdomen, trying to lie down, stretching out Physical exam findings In acute stages abdomen is pear shaped Feces pass initially and then stop as distal segments empty Rectal Thick strands of mucous covered feces Multiple distended loops of small intestine Physical exam findings Tachycardia Dehydrated Hypochloremic, metabolic alkalosis Metabolic acidosis- intestinal strangulation Surgery Right flank exploratory If in good condition and a dairy cow I would do standing If cow severely ill or colicky I would do surgery in lateral recumbency Easier to correct volvulus while standing Surgery If cow standing and volvulus at mesenteric root is easy to palpate I try and untwist without exteriorizing the small intestine Use wrist and arm to swing intestine back into place If volvulus is very tight or involves a large portion of the SI the bowel must be exteriorized. Start at ileum and work proximally Surgery As you move proximally untwist the volvulus manually Check yourself by palpating mesenteric root and make sure mesentery is straight If bowel is ischemic it must be resected and anastomosis performed Same as for intussusception After correction replace SI into omental bursa and close abdominal incision Prognosis Good for uncomplicated correction Prognosis worsens for strangulated bowel and endotoxemia Volvulus of intestine around mesenteric root Involves SI, cecum, and majority of ascending colon If not corrected promptly disease is usually fatal Primary clinical sign is unrelenting pain Kick at abdominal wall Throw themselves down Roll over and stand up again Clinical signs Tachycardia Bilateral abdominal distension Multiple pinging areas over the right side Rectal multiple distended loops of SI, distension of cecum and large intesinte tight bands of mesentery Treatment IV fluids NaCl +/- hypertonic saline NSAIDs and antimicrobials Right paralumbar fossa laparotomy Mesenteric root is palpated Decompress distended segments with suction Treatment Affected segments are untwisted Find cecum and try to untwist it first Once cecum is identified it will make it easier to determine which way to manipulate the SI and large intestine Resection performed if needed Mesenteric volvulus Cecal volvulus with necrosis Prognosis Generally guarded because of large amount of intestine involved If corrected early with no bowel ischemia prognosis is favorable Some cattle die of shock following correction of the volvulus and release of endotoxins Other causes of SI obstruction Persistent vitelloumbilical , persistent round ligament of the liver, parovarianomental bands, persistent urachal remnant, remnant of the ductus deferens in steers Obstruction relieved by cutting band/remnant and removal of entangled intestine Resection and anastomosis if required Diseases of the cecum Anatomy Blind-ended sac Apex points caudally Found in omental bursa or outside the bursa Continuous with the large colon cranially- no valve Ileum empties into cecum at ileocecocolic junction Diseases of the cecum Anatomy Dorsally, cecum attached to the large colon via the cecocolic fold Ventrally, cecum attached to ileum by the ileocecal fold Diseases of the cecum Cecal dilatation and Cecal volvulus Causes are not known Secondary to other abdominal diseases Heavy concentrate feeding with increased volatile fatty acid production Physical exam- cecal dilatation Some forms of cecal dilatation are assymptomatic and found incidentally on rectal Anorexia Depression Decreased milk production Ping Extends from tuber coxae to 11th or 12th rib Physical exam- cecal dilatation Decreased fecal production Mild colic Rectal Cecal apex pointed caudally 8-12 cm in diameter Physical exam- cecal volvulus Tachycardia Tachypnea Moderate colic Ping is larger and right paralumbar fossa may be distended May succuss a fluid filled viscus on right side Scant feces Physical exam- cecal volvulus Rectal Body of cecum palpable Apex rotated away can not be palpated May palpate proximal colon as distended viscus adjacent to cecum Clinical pathology Cattle with cecal dilatation generally have normal lab values Cecal volvulus Dehydrated- elevated PCV/TP Hypochloremic, hypokalemic metabolic alkalosis may be secondary to obstruction of ileocecocolic orifice obstruction of SI outflow abomasal reflux into rumen Treatment Simple cecal dilatation may be resolved with medical therapy IV calcium IV NaCl Treat ketosis Treatment Surgery is recommended for unresponsive cecal dilatation and all cases of cecal volvulus Criteria Tachycardia Abdominal pain Scant feces Preoperative treatment Place IV catheter NaCl- fluid of choice If 8-10% dehydrated I would administer 2 liters of hypertonic saline Flunixin meglumine +/- antimicrobials Right flank laparotomy Locate the cecal apex and exteriorize Can decompress cecum with needle and suction Typhlotomy makes correction easier Small 6-8 cm incision at cecal apex Have assistant hold cecal apex Surgeon milks cecal and large colon contents out through typhlotomy Surgery Typhlotomy closed in 2 layers First layer- simple continuous full thickness Second layer- Cushing Use 2-0 absorbable suture material Lavage cecal apex Untwist cecum and return to abdomen Make sure bowel in normal anatomical positions Close abdominal wall Aftercare Diarrhea not uncommon after surgery and should resolve in 3-5 days Continue IV fluids until cow can maintain normal hydration on their own Flunixin 2-3 days Antimicrobials 3-5 days Feed as soon as hungry Complications Recurrence rate is 10% Can perform typhlectomy for recurrent cases Severe cecal volvulus resulting in cecal ischemia requires resection of the cecum. Resection requires general anesthesia and is technically difficult Diseases of the large colon Anatomy of ascending colon- 3 parts Proximal loop extends cranially from the cecum and then doubles back and proceeds caudal just dorsal to first segment at level of caudal flexure of duodenum proximal loop goes from right to left around left side of mesentery Spiral colon 2 loops going in- centripetal Central flexure 2 loops going out- centrifugal Anatomy Distal loop Proceeds along left side of mesentery and extends cranially adjacent to proximal loop Continuous with short transverse colon Descending colon Suspended by mesocolon, continues caudally towards the rectum Surgical diseases of the large colon Obstruction of the spiral colon by extraluminal obstruction May be secondary to adhesions following previous abdominal surgery Mesenteric fat necrosis Intraperitoneal adhesions from irritating drugs through right paralumbar fossa Obstruction of small colon Clinical signs Gradual intestinal obstruction Rectal firm palpable mass in right paralumbar fossa palpable adhesions Surgery Right paralumbar fossa laparotomy Identify mass of adhesions Locate section of bowel proximal to obstruction and outer loop of spiral colon If these two segments can be located use a side-to-side anastomosis to bypass the adhesions If lesion can be bypassed the prognosis is fair Obstruction of descending colon and rectum Can be caused by intraluminal or extraluminal obstruction Causes Lipomas Fat necrosis Phytobezoars Enteroliths Neoplasia Adhesions Obstruction of descending colon and rectum Descending colon can also be obstructed by becoming incarcerated in a rent in the mesocolon Ischemic bowel must be resected Treatment Intraluminal obstructions can be removed with colotomy through a right paralumbar fossa approach Treatment Impacted feces may respond to extraluminal massage and injection of mineral oil or DSS directly into impacted segment Focal adhesions or areas of fat necrosis may be bypassed depending on access with a side-to-side anatomosis Atresia coli Most common cause of obstruction in newborn calf Usually involves the spiral colon Pathogenesis Rectal palpation of amniotic vesicle at less than 42 days of gestation Hereditary predisposition Most common breed is the Holstein Clinical signs Progressive abdominal distension and no passage of feces Calves appear normal at birth but usually within 24-48 hours calves become anorexic, develop abdominal distension, depression, and dehydration May have normal temp if peritonitis not present; elevated if intestine has ruptured Clinical signs Tachycardia Fluid balloted through abdominal wall Pings associated with gas accumulation Clinical Pathology Increased PCV, TP may be elevated if colostrum absorbed Measurement of IgG may indicate partial or complete failure of passive transfer Electrolyte disturbances Treatment Affected animals must have surgery to survive Calf should be of sufficient value to warrant expensive surgical correction Owners should be discourage from using these animals as breeding stock If abdominocentesis indicated rupture euthanasia should be considered Treatment IV fluids Antimicrobials Anti-inflammatories Plasma or whole blood transfusion if failure of passive transfer present Surgery General anesthesia Right paralumbar fossa Goals of surgery Remove meconium from proximal intestine Remove proximal blind loop to intestine of fairly normal diameter Reestablish patent GI tract Surgery Open entering abdomen distension of SI, cecum, and large colon is obvious Needle decompression of gas Exteriorize cecum and large colon Typhlotomy performed to empty meconium Close typhlotomy as described previously Locate proximal blind end Surgery Proximal blind end is located and dissected free of its mesenteric attachment Stay close to mesenteric border to avoid disrupting blood supply Resect proximal blind end to intestine of normal diameter Hand suture or staple Resection is omitted by some surgeons Surgery Insert soft rubber catheter into rectum Be careful- it is possible to perforate the descending colon Align proximal end to descending colon Perform hand sutured or staple side-to-side anatomosis 3-0 absorbable suture in simple interrupted pattern Lavage and close abdominal incision Atresia coli Atresia coli Atresia coli Atresia coli Atresia coli Atresia coli Complications Number one complication is peritonitis Second most common is anastomotic failure Can be surgeon error associated with stapling equipment Incisional infection Diarrhea Impaction at anastomosis Pneumonia Long-term complications Intestinal obstruction secondary to adhesion formation Slow growth Chronic diarrhea Incisional abscesses Chronic cecal dilatation Aftercare IV fluids until calf can maintain hydration with oral intake Oral feeding can begin within 24 hrs of surgery Antimicrobials Anti-inflammatories Prognosis Barring complications long-term survival rate of affected animals is fair to good Owners should be aware that long-term survivors may have loose feces and not grow normally