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19 Colonic Volvulus Michael D. Hellinger and Randolph M. Steinhagen Introduction/Historical Perspective Volvulus of the bowel refers to a twisting or torsion of the intestine about its mesentery. The term volvulus, which may involve any segment of the intestinal tract from stomach to rectum, is a Latin word for twisted used by the Romans to signify this condition.1 Volvulus of the colon usually occurs in the sigmoid or cecum, but may involve any segment of colon. In addition, synchronous volvulus of the sigmoid and cecum,2 or sigmoid and ileum may occur.3 In the United States, volvulus represents a rare cause of intestinal obstruction, encompassing less than 5% of large bowel obstructions. However, worldwide it is a much more common form of large bowel obstruction, representing more than 50% of the cases in some countries.4–6 The first record of colonic volvulus is found in the Ebers Papyrus from ancient Egypt. This record stated that either volvulus would spontaneously reduce or the segment of bowel would “rot in his belly.” The writings further document that if this condition did not resolve, the patient should be prepared for remedies to induce detorsion. As early as 1500 BC, therefore, it was recognized that detorsion was crucial for resolution of this condition. Even in ancient times, a high fiber diet was believed to be contributory to the development of volvulus. At that time, treatment was directed at symptoms and relief of the obstruction. External manipulation combined with purgatives was the treatment of the times. Hippocrates advocated use of a 10-digit long suppository and air blown into the anus with a metal worker’s bellows. This is perhaps the earliest predecessor to today’s sigmoidoscopic decompression.1,7 During subsequent years, reports concerning colonic volvulus were infrequent. It was not until the 19th century, when investigators began attempting to determine causes of disease, that this entity was discussed further. Perhaps the fact that volvulus was not recognized as a cause of colonic obstruction was accounted for by the rarity of the diagnosis before the 1800s. In 1872, Crise reported 12 cases, and in 1884 Treves reported 34 cases of colonic volvulus. In 1894, Obalinski recognized regional variations in frequency of volvulus.1,7,8 286 Throughout most of the 19th century, management was nonoperative. Operative intervention was reserved for lifethreatening situations. High mortality rates for intestinal operations in the face of obstruction were the reasons cited in avoiding surgery. With advances in anesthesia and antisepsis, surgical procedures were developed. In 1883, Atherton performed the first successful operative detorsion of a sigmoid volvulus in the United States. The next year, Treves recommended colectomy for volvulus complicated by gangrene. By 1889, in fact, all of the surgical options for volvulus, including detorsion, -pexy, and resection with or without stoma, had been described.1,7 Early in the 20th century, with improvements in early diagnosis and rapid therapy, mortality rates began to decrease and surgical therapy became the mainstay. Mortality rates decreased from 30%–60% to under 20%. Mortality for gangrenous bowel remained high (30%–40%), reflecting a delay in diagnosis and treatment. Moynihan’s statement in 1905 that a mortality of greater than 10% is the mortality of delay had been confirmed in many series.1,7 Until the mid-20th century, immediate surgical intervention was the standard of care. In 1947, Bruusgaard, from Norway, challenged the routine surgical approach, and reported a success rate of 86% for nonoperative reduction of sigmoid volvulus with proctoscopic decompression and placement of a rectal tube.9 This paved the way for today’s therapeutic algorithms in the management of colonic and specifically sigmoid volvulus.1,7 Finally, with widespread use of flexible endoscopy, many authors have reported successful detorsion and decompression of all forms of colonic volvulus using the colonoscope or flexible sigmoidoscope.10–15 Because of high recurrence rates, these endoscopic methods are currently recommended as definitive treatment only for very high-risk individuals who are too ill to undergo surgery, and as a temporizing measure until eventual surgery under more controlled conditions for all other patients.1,7,9,14–16 The differential diagnosis of colonic volvulus encompasses any cause of colonic distention. This includes all of the mechanical as well as the nonobstructive causes. Mechanical causes include colonic and extracolonic neoplasms, as well as 19. Colonic Volvulus 287 benign entities such as diverticulitis and inflammatory bowel disease. Nonobstructive causes include colonic pseudoobstruction (Ogilvie’s syndrome), and various intraabdominal processes that may result in an intestinal paralysis. In addition, Hirschsprung’s disease must also be considered.5,6,17 Cecal Volvulus Incidence and Epidemiology Worldwide, cecal volvulus accounts for 40%–60% of all colonic volvuli. Originally described in 1837 by Rokitansky, it remains, however, an uncommon cause of intestinal obstruction. The worldwide incidence is estimated at 2.8–7.1 per million people per year. Most reported cases occur in younger individuals with a predilection for females.18–20 In a review of the published literature between 1959 and 1989, Rabinovici et al.19 found a mean age of 53 years and a female to male ratio of 1.4:1. Pathogenesis/Etiology True cecal volvulus is actually an axial torsion of the cecum, terminal ileum, and ascending colon about its mesentery (Figure 19-1A). A variant, cecal bascule (Figure 19-1B), occurs when the cecum folds anteriorly over the ascending colon without an axial twist. This represents approximately 10% of cases of cecal volvulus. Review of patient characteristics indicates that there is a high rate of prior abdominal operations in patients who subsequently develop cecal volvulus, and previous surgery has been considered to be a potential causative factor. A clear prerequisite is a mobile cecum and ascending colon. A congenital component involves lack of fixation of the right colon, which then assumes an intraabdominal position.4,18–20 In fact, a cadaver study revealed an 11% incidence of freely mobile right colons, and a 26% incidence of cecal mobility sufficient to allow folding. The authors concluded that 37% had cecums mobile enough to allow for volvulus.4 However, because cecal volvulus is so rare, factors other than cecal mobility must be involved. Prior abdominal surgery with colonic mobilization, recent surgical manipulation, adhesion formation, congenital bands, distal colonic obstruction, pregnancy, pelvic masses, extremes of exertion, and hyperperistalsis have all been implicated.4,18–20 During abdominal surgery, excessive mobilization or manipulation of the cecum and ascending colon or placement/withdrawal of packs may precipitate postoperative volvulus.4 Previous reports of cecal volvulus reveal that 30%–70% of patients had undergone prior surgery.19,20 In the long term, an adhesive band may act as a fulcrum for a previously mobilized ileum and right colon to rotate axially. Displacement of the cecum by an enlarged uterus or pelvic mass may also promote volvulus. In fact, several series report that 10% of patients with cecal volvulus are pregnant at the time of presentation.4,20 FIGURE 19-1. A Schematic illustration of a cecal volvulus. B Schematic illustration of a cecal bascule. Clinical Presentation Symptoms and signs of cecal volvulus are that of small bowel obstruction. The majority of patients present with abdominal 288 M.D. Hellinger and R.M. Steinhagen pain, distention, constipation, nausea, and vomiting. Abdominal distention is less marked than with more distal forms of colonic volvulus. The presentation may be that of an acute obstruction or one of an intermittent or recurrent pattern. In the intermittent pattern, because duration of symptoms is brief, diagnosis may be quite difficult. Acute volvulus results in a closed loop cecal obstruction and distal small bowel obstruction. This may progress to a more fulminant presentation when ischemia and gangrene develop. At that point, the patient will present with peritoneal signs and systemic manifestations of an acute abdominal process. Before onset of gangrene, fever and leukocytosis are unreliable factors.17–19,21 Diagnosis The diagnosis is most often made on the basis of the combination of clinical presentation and plain abdominal films or barium enema. Plain films may identify the classic coffee bean deformity directed toward the left upper quadrant (Figure 192A). If not, barium enema may reveal a “bird’s beak” or column cut-off sign in the right colon (Figure 19-2B).4,17–19 In the review by Rabinovici et al., 53% of cases were diagnosed preoperatively with clinical evaluation combined with radiologic investigation. The diagnosis was suspected in 46% of plain films, and barium enema was diagnostic in 88% of cases when obtained. However, 47% were not diagnosed until laparotomy.18 Although barium enema is of clear value when the diagnosis is in question, in obvious cases, performance of this study may needlessly delay surgical therapy. It therefore should not be routinely used.4 Treatment/Outcome Laparotomy remains the primary treatment modality for cecal volvulus. Many patients are not diagnosed until exploration, and nonoperative modalities have generally been unsuccessful. However, both radiographic and endoscopic reduction have been reported. Whereas radiographic attempts at reduction are generally believed to carry a high risk of perforation, other modalities have been used as temporizing measures.4,5,16,18 Percutaneous decompression via computed tomographic scan guidance has been reported to be effective in decompressing a massively dilated colon in otherwise inoperable candidates.22,23 Although significantly less efficacious than in the treatment of distal volvulus, colonoscopic reduction of cecal volvulus (Figure 19-3) has been reported with some success. Reasons cited for limited use of this approach include difficulty traversing the extent of unprepared bowel to reach the right colon, difficulty performing the detorsion, the relative infrequency in which the diagnosis is made before laparotomy, and the higher rate of ischemic changes in cecal volvulus than in sigmoid volvulus. In fact, several authors have condemned this approach as only unnecessarily delaying definitive surgical intervention and potentially placing the patient at risk for perforation. However, if successfully used, there may be a FIGURE 19-2. A Plain abdominal X-ray of a cecal volvulus with a “coffee bean” deformity evident in the left upper quadrant. B Barium enema study of a cecal volvulus revealing a bird’s beak deformity. 19. Colonic Volvulus FIGURE 19-3. Colonoscopic reduction of a cecal bascule. relatively low rate of recurrence and the requirement for subsequent surgery is debated.4,5,10,11,16,18,24,25 In general, the majority of individuals undergo surgical intervention with a clear diagnosis of cecal volvulus, for complete bowel obstruction, or for an acute surgical abdomen. Obviously, in the face of gangrenous or ischemic bowel, resection is mandatory. When viable bowel is encountered, although resection is the preferred option, other alternatives exist. These include detorsion alone or combined with some fixation procedure. Fixation options include cecopexy and/or cecostomy. Appendicostomy has also been reported.4,5,18,19,25,26 Generally, fixation is accomplished by cecopexy and/or cecostomy. Cecopexy is performed by elevating a lateral peritoneal flap along the entire length of the ascending colon, and suturing the flap to the serosa of the anterior colonic wall, thereby placing the ascending colon in a partially retroperitoneal location, and eliminating the excess mobility (Figure 19-4). An advantage of tube cecostomy is that it not only anchors the cecum, but also provides a vent for the distended colon. Cecostomy is relatively simple to perform, and after removal of the tube, spontaneous closure is common.4,5,18,25 In a review of the literature, Rabinovici et al.19 found that detorsion, cecopexy, and cecostomy all carry similar recurrence rates of 12%–14%. Interestingly, they also noted a mortality for cecostomy triple that of either cecopexy or detorsion (32% 289 FIGURE 19-4. Colopexy and cecostomy for cecal volvulus. versus 10% and 13%, respectively). Other authors have reported recurrence rates ranging from 0% to 30%.4,5,18,25 Resection, however, carries virtually no risk of recurrence and is not associated with a higher rate of postoperative complications when compared with cecopexy alone.18,25 After resection, primary anastomosis can usually be safely performed. However, in the face of gangrenous bowel, end ileostomy may be a safer procedure. The ultimate decision regarding intestinal anastomosis is one made at the time of surgery, taking into account degree of contamination, and the patient’s overall status.4,5,18,19,25,26 Overall mortality is independent of the procedure chosen, rather it is related to whether or not the surgery is elective or emergent and the presence or absence of gangrene. Literature documents no mortality in the elective situation. If viable bowel is found at the time of an emergency operation, mortality ranges from 7% to 15%. This increases to 33%–41% in the face of gangrenous bowel.4,18,25 Transverse Colon Volvulus Incidence and Epidemiology Volvulus of the transverse colon is an exceptionally rare finding. It is estimated to represent from 1% to 4% of all forms of colonic volvulus. However, in Eastern and Scandinavian 290 countries, it may comprise 30%–40% of cases. This form of volvulus tends to occur more often in the young, with most series showing a peak incidence in the second through fourth decades of life. There is a two- to threefold female predominance.4,18,20,27–29 Pathogenesis/Etiology Although anatomic factors are key to the development of transverse colon volvulus, physiologic, rather than congenital, factors seem to have a crucial role in the development. These patients frequently have a history of chronic constipation and/or laxative abuse, previous abdominal surgery, a diet high in fiber, recurrent distal obstruction, and institutionalization. There are also reports, however, of an association with malrotation, Hirschsprung’s disease, and Chilaiditi’s syndrome. Finally, adhesive bands, frequently reported in these patients, may act as a fulcrum around which the bowel can twist. Specific factors that may increase the risk of occurrence are a redundant or elongated transverse colon with narrow mesenteric attachments, narrowed distance between the flexures, and an absence or paucity of fixation of the mesentery. These factors increase the likelihood of an axial rotation of the transverse colon about its mesentery.4,18,20,27–31 M.D. Hellinger and R.M. Steinhagen recurrence, and may therefore be best reserved for those highrisk individuals who show no signs of compromised bowel.12,14,18 However, colonoscopy may serve to confirm intestinal viability and allow for a less emergent definitive procedure to be performed.30 Operative procedures include detorsion with or without colopexy, and resection. Most authors recommend either segmental transverse colectomy or extended right colectomy as definitive treatment. Clearly, in the presence of nonviable bowel, resection is mandatory.12,14,18,30–32 As in cecal volvulus, the decision regarding primary anastomosis versus diversion is made during surgery, taking into account the severity of the disease process and the patient’s overall condition. When viable bowel is encountered, several different colopexy procedures have been reported. These include suture of the greater omentum, transverse mesocolon, or transverse colon itself to the anterior abdominal wall and/or pelvis,18,30,32 and the U colopexy reported by Mortensen.31 In this procedure, after reduction and needle decompression of the volvulus, the redundant U-shaped loop of transverse colon is sutured to the adjacent limbs of ascending and descending colon (Figure 19-5). Recurrence from either detorsion or colopexy has been reported to range from 30% to 75%, whereas resection eliminates virtually all risk of recurrence.25,32 Mortality, however, Clinical Presentation Transverse colon volvulus presents as a large bowel obstruction. Presentation may be as a subacute recurring process or may take a more fulminant course. The subacute form is associated with repetitive episodes, each with gradual onset. Although associated with significant abdominal distension, pain is mild to moderate, and vomiting is usually absent. Up to 50% of patients admit to previous episodes. The fulminant form is associated with less distension, but marked pain and vomiting. Clinical deterioration is rapid in these cases.4,17,27–29,31 Although diagnosis may be suspected on clinical presentation, plain films are rarely diagnostic. The diagnosis is therefore usually made at the time of exploration. Plain films may reveal a distended proximal colon with decompressed distal bowel and two distinct air-fluid levels representing two limbs of the volvulized transverse colon. This has been described as a bent inner-tube appearance with the apex pointing inferiorly. Barium contrast studies, if performed, will demonstrate a bird’s beak deformity at the distal transverse colon. However, awaiting these studies only leads to a delay in definitive management.4,17,27–30 Treatment/Outcome Although successful endoscopic decompression has been reported, surgical intervention is the recommended treatment modality. Based on literature from surgical detorsion, it is assumed that endoscopic treatment will lead to a high rate of FIGURE 19-5. Parallel coloplasty as described by Mortensen.31 19. Colonic Volvulus 291 from resection has been reported to be as high as 33%. This is primarily in the setting of gangrene or perforation.18,27 In these cases, mortality may be decreased by construction of an end stoma or extended resection with ileocolic anastomosis.30 Splenic Flexure Volvulus Incidence and Epidemiology Having been described in fewer than 50 patients in the English literature, volvulus of the splenic flexure of the colon is the rarest form of colonic volvulus. It is estimated to represent 1%–2% of all cases of colonic volvulus. It seems to be more common in women and occurs at a younger age than cecal or sigmoid volvulus.4,13,25,33,34 FIGURE 19-6. Barium enema study of a chronic splenic flexure volvulus. Arrows indicate the point of rotation and bird’s beak deformity. Pathogenesis/Etiology Treatment/Outcome The infrequency of this form of volvulus is believed to be the result of multiple attachments of the splenic flexure, and the retroperitoneal position of the descending colon. Three ligaments, the gastrocolic, splenocolic, and phrenocolic, are responsible for fixation of the splenic flexure. Congenital absence, laxity, or iatrogenic disruption of these ligaments may lead to excessive mobility of the splenic flexure. In addition, an intraperitoneal descending colon and adhesive bands from previous surgery may further predispose to the development of this form of volvulus. In fact, up to twothirds of patients have had prior abdominal surgery. Finally, it has been speculated that chronic constipation may lead to redundancy of the colon and elongation of the mesentery. This may possibly create laxity of the ligamentous attachments.4,13,25,33,34 Although colonoscopic and fluoroscopic decompression have been reported, most reports have identified surgery as the primary mode of management. Surgical options include resection with or without stoma formation, or detorsion with or without colopexy. Segmental resection may be considered; however, the majority of these patients will have an associated redundant, dilated colon and a history of chronic constipation. Therefore, these patients may be better served by undergoing an extended resection with an ileosigmoid or ileorectal anastomosis. Stomas should be reserved for cases involving gangrenous bowel with perforation and peritoneal contamination, or for other high-risk cases.4,13,25,34 No mortality has been reported with either form of surgical management. The complication rate, excluding recurrence, is in the range of 10%. Resection carries a 0% recurrence rate. However, the recurrence rate after detorsion alone, whether performed surgically, endoscopically, or fluoroscopically, is approximately 20%–25%. As a result of these high recurrence rates, nonoperative decompression/detorsion should be reserved for extremely high-risk patients who are not candidates for surgical intervention, or as a temporizing measure before a semi-elective definitive resection.4,13,34 Clinical Presentation As in transverse colon volvulus, the presentation may be acute and fulminant, or a more chronic or subacute event. Many patients have a history of severe chronic constipation, with longstanding laxative abuse. At presentation, the majority of patients have significant abdominal distention and pain. Although nausea and vomiting are common, obstipation is rare. Very few patients present with strangulation, gangrene, or findings of an acute surgical abdomen.4,33,34 Four features have been described radiographically that may suggest splenic flexure volvulus. They are: 1) a markedly dilated air-filled colon with an abrupt termination at the splenic flexure; 2) two widely spaced air-fluid levels, one in the cecum and the other in the transverse colon; 3) an empty descending and sigmoid colon; and 4) a bird’s beak obstruction at the splenic flexure on contrast enema examination (Figure 19-6). An additional sign is a crescenteric gas shadow in the left upper quadrant of the abdomen.13,33 Sigmoid Volvulus Incidence and Epidemiology Although it is the most common form of volvulus seen, volvulus of the sigmoid colon is not very common in the United States and Western Europe, accounting for less than 10% of all cases of large bowel obstruction.5,6,19,35 In some regions of Asia, Africa, and other less-developed portions of the world, however, the situation is significantly different. In these areas, sigmoid volvulus accounts for 20%–50% of the 292 cases of intestinal obstruction. Overall, there is a substantial male predominance, especially in developing nations. However, sigmoid volvulus is the most common cause of intestinal obstruction in pregnancy, accounting for nearly 45% of all intestinal obstructions in this group of women.3,4,5,19 The reasons for geographic differences in incidence are thought to be primarily related to diet. In the West, relatively lower amounts of fiber are consumed, resulting in a much higher incidence of colorectal cancer and diverticular disease, which are the more common etiologies for colonic obstruction in these areas. In less-developed regions of Asia and Africa, extremely high fiber diets result in significantly elongated colons, and lead to development of sigmoid volvulus, in relatively young patients. Pathogenesis/Etiology Any condition that results in an elongated colon predisposes to the development of volvulus. In order for volvulus of any part of the intestinal tract to occur, there must be a long redundant, mobile segment, with a relatively narrow mesenteric attachment, such that the sites of fixation at each end are relatively close together. The sigmoid colon is the ideal location for this configuration: the sigmoid can be extremely redundant and mobile and the sites of fixation at the descendingsigmoid junction and the rectosigmoid junction are often in close proximity to each other.3,19 Although a single etiology has not been identified, several theories do exist. In 1849, in his Manual of Pathological Anatomy, Von Rokitansky proposed that the primary causative factor was a “congenital or acquired long, loose, and floppy mesentery.” Thirty-five years later, in his text of intestinal obstruction, Treves indicated that the loop in sigmoid volvulus “must be of considerable length, the mesocolon must be long and very narrow at its parietal attachment, so that two ends of the loop may be brought as close together as possible.”3 In the West, the typical patient with sigmoid volvulus is an elderly institutionalized male, often receiving psychotropic medications, who is usually extremely constipated. Other factors that have been implicated are laxative abuse, previous abdominal surgery, and diabetes.3,5,18 In other parts of the world, the patients are significantly younger.24,36,37 Megacolon from any etiology, but especially Hirschsprung’s disease or Chagas’ disease, predisposes to volvulus.3,8,19 Gross features of the sigmoid colon include progressive widening and eventual loss of taenia coli, absence of appendices epiploicae, and a thickened narrowed fibrous mesentery. The scarring forms patches and bands coined “shrinking mesosigmoiditis” by Brusgaard, and is believed to be the result of previous episodes of volvulus.9,19,38 The rotation may be either clockwise or counterclockwise. Once the rotation has reached 360 degrees, a closed loop obstruction occurs. Hyperperistalsis and fluid secretion into the closed loop add to increased pressure and tension. Eventually, as blood flow is M.D. Hellinger and R.M. Steinhagen compromised, ischemia and necrosis develop. Additionally, the diminished blood flow may lead to arterial and venous thrombosis. Three patterns of necrosis have been described: 1) at the neck of the volvulus, 2) any location within the closed loop, and 3) in the proximal descending colon or distal rectum because of retrograde mesenteric thrombosis. Because the sigmoid loop is usually chronically thickened, it is unlikely for a perforation to occur in this location. In the face of a competent ileocecal valve, perforation is more common in the cecum.39 Clinical Presentation As previously described, the patient is typically a male nursing home resident, on psychotropic medications, with a history of chronic constipation. These patients may not complain of pain, but rather a caregiver notices an extremely long interval between bowel movements, associated with significant abdominal distension. In younger patients, constipation, distension, and abdominal pain are the predominant symptoms.38 Before arrival at the hospital, the patient may have been given enemas or laxatives, without relief. This therapy may have, in fact, made the distension worse. There is often significant delay between onset and evaluation.40,41 It has been reported that 40%–60% of patients will give a history of having had similar episodes.4,38 On presentation, the distension is often dramatic. Unlike the patient with fecal impaction, the rectal ampulla is empty. Plain abdominal films typically show massive colonic distension, with or without small bowel dilatation (depending on the competence of the ileocecal valve). The very large sigmoid loop will be orientated toward the right upper quadrant. The adjacent walls of the sigmoid will appear to be thickened, arising out of the left lower quadrant, giving the classical “bent inner tube” sign (Figure 19-7A).38 In the majority of cases, plain radiographs are sufficient to establish the diagnosis.40 In fact, plain abdominal X-rays alone are diagnostic in 60%–75% of cases.39,42 However, the massive distension may, occasionally, make the diagnosis difficult to establish with certainty. In those cases, a contrast enema should be obtained. This study will show the obstruction at the rectosigmoid junction, with the classical bird’s beak configuration (Figure 197B).5,39 The addition of barium enema to the plain abdominal X-rays may increase the diagnostic yield to near 100%.42 The major diagnosis from which sigmoid volvulus must be distinguished is colonic obstruction caused by neoplasm. Usually the abdominal X-rays can distinguish one from the other; however, in the presence of truly massive distension, differentiation may be difficult. At the time of attempted sigmoidoscopic detorsion, the obstructing neoplasm will hopefully be visualized and the true diagnosis will be apparent. The other condition that may cause clinical confusion is colonic megacolon associated with abnormal colonic motility. This condition also presents in elderly, constipated nursing home patients. The X-rays can look remarkably similar. 19. Colonic Volvulus 293 FIGURE 19-7. A Plain abdominal X-ray of a sigmoid volvulus indicating the “bent inner tube” sign. B Barium enema study of a sigmoid volvulus indicating the bird’s beak deformity and complete obstruction to retrograde flow of contrast. Because rectal tube decompression will generally rapidly and successfully relieve the distension associated with this form of megacolon, distinction from volvulus can be difficult. It is important to make the distinction, however, because this condition is also associated with a high incidence of recurrence, but will not be successfully treated by sigmoid resection. In one series, a 37% incidence of recurrent “volvulus” was seen after sigmoid resection and anastomosis. However, virtually all of these patients had megacolon-associated abnormal colonic motility.43 Treatment/Outcome The patient with sigmoid colon volvulus should be hydrated and resuscitated. Since 1947, when Bruusgaard9 reported a 90% success rate with sigmoidoscopic detorsion, the mainstay of emergency therapy has generally been detorsion and decompression. Detorsion of sigmoid volvulus has been described using several techniques, including rigid proctoscopy, flexible sigmoidoscopy or colonoscopy, blind passage of a rectal tube, and use of a column of barium during barium enema examination.7,9,10,14,15,24 Successful decompression using one of these techniques is generally reported in the range of 70%–80%.18,39–41,44 A significant concern is that the sigmoid may already be gangrenous. Several authors in Asia and Africa have noted an incidence of gangrene approaching 50%, as well as a significant incidence of double volvulus (ileosigmoid knotting) rarely seen in the West, and have therefore recommended emergency laparotomy without attempts at detorsion.36,37,45–47 If ischemic mucosa is visualized, attempts at detorsion should be immediately abandoned and operative intervention should be undertaken emergently. For this reason, we strongly recommend using only those detorsion techniques that visualize the mucosa before detorsion. Attempts at detorsion via blind passage of a rectal tube should be avoided. Attempted detorsion of nonviable bowel will lead to a high incidence of perforation and peritonitis. The presence of nonviabilty should be suspected by the presence of signs and symptoms of compromised bowel and/or systemic sepsis, such as fever, 294 leukocytosis, and especially localized tenderness over the sigmoid loop. If these are present, decompression should not even be attempted. The patient should be taken for emergent surgery. In approximately 25% of cases, the site of the twist will be more proximal than can be reached with a rigid proctoscope.14 Use of flexible scopes can obviate this problem. The major complication associated with attempted detorsion is inadvertent perforation. This is more likely in the presence of gangrene, but can occur with viable bowel as well. Once decompression has been accomplished, there is usually forceful evacuation of flatus and stool (frequently all over the clothes and shoes of an unsuspecting novice) and visible deflation of the patient’s abdominal distension. A rectal tube should then be gently inserted into the colon to a point proximal to the site of the twist (which is usually within 20 cm of the anus). The tube should then be fixed in place, to allow continued decompression and prevention of recurrence. A plain abdominal film should be obtained to document decompression and the patient should be admitted to the hospital. Successful detorsion provides the advantage of converting a surgical emergency to an elective situation. Over the next several days, bowel function is likely to return to normal. Medical conditions (cardiac, pulmonary, renal, etc.) should be addressed, electrolyte abnormalities should be corrected, and the patient’s condition optimized. Colonoscopy, to rule out a proximal lesion, should be performed, and then a decision must be made. The rectal tube can be safely removed and the patient could be discharged from the hospital; however, it is well established that the rate of recurrent sigmoid volvulus is in excess of 25%.48,49 In fact, most authors document a recurrence rate of greater than 50%, and some report recurrences as high as 80%–90%.18,21 However, one report notes that 15 of 29 patients (52%) with sigmoid volvulus never required surgery. Twenty-three of 26 successfully decompressed patients were observed. Twelve recurred, six of whom were again decompressed and observed. Four of these patients had no further recurrence. Whereas none of the conservatively treated patients developed a complication, 43% of the surgical patients died.35 The overall condition of the patient, the ease with which the volvulus was untwisted, and whether or not there were previous episodes of volvulus, are all factors that must be considered in the decision to perform definitive surgery. The standard elective surgical procedure is sigmoid resection with primary anastomosis; however, a number of nonresective techniques have been described, including nonsurgical endoscopic sigmoidopexy with or without tube fixation,17,50,51 extraperitoneal sigmoidopexy,52 sigmoidopexy to the transverse colon and/or the parieties,17 mesosigmoplasty,53,54 colopexy with banding,55 mesenteric fixation,7 and laparoscopic fixation.56 Although several authors have reported excellent results using pexy without resection,52–54 others have reported recurrence rates in excess of 25%.38 Whereas recurrence after resection approaches zero, resection with anastomosis was historically accompanied by relatively M.D. Hellinger and R.M. Steinhagen substantial morbidity and mortality,42 prompting a number of investigators to seek less risky alternatives. Bhatnagar and Sharma52 reported a series of 84 patients treated by sigmoidopexy with extraperitonealization. They reported a mortality of 9%. Patients were followed for a mean of 6.7 years with no evidence of recurrence (48 patients were followed for more than 5 years). Salim,55 however, reported on a technique of percutaneous deflation, followed by tube detorsion and decompression, and finally intraperitoneal sigmoidopexy. He conducted a prospective, randomized trial of this nonresectional technique compared with resection and primary anastomosis. Of the initial 21 patients randomized to the decompression followed by surgical arm, six required emergency surgery. The remaining 15 were able to undergo an elective resection. Of note, he reported no recurrences and a mortality of 0% in the colopexy group as opposed to 13% in the group undergoing resection.55 Finally, the technique of mesosigmoidoplasty deserves discussion. This procedure is performed by incising the elongated sigmoid mesentery vertically along its axis. Peritoneal flaps are then created which are then approximated transversely (Figure 19-8). This procedure thereby creates a shortened, broad mesentery precluding future bowel rotation. Although one author has reported a recurrence of 28%, most report recurrences of less than 2%. Mortality ranges from 0% to 7%.53,54 Modern surgical and anesthetic techniques, including the use of surgical staplers, have reduced operative complications substantially. Resection with anastomosis, therefore, should currently be considered the standard of care for elective cases. However, in circumstances in which continence is an issue, an end stoma may be a better alternative. Colostomy via a FIGURE 19-8. Mesosigmoidoplasty. A A longitudinal peritoneal incision is made in the elongated, narrow mesentery. B The incision is then closed transversely, broadening the mesenteric base and shortening the height of the sigmoid loop. 19. Colonic Volvulus minimal left lower quadrant incision has been suggested for debilitated patients, too sick to undergo formal laparotomy.57 Laparoscopic techniques have also been applied,58–60 but in general, because the redundant distended colon obscures the working space and the incision required to deliver the specimen is also large enough to exteriorize the redundant sigmoid colon and perform an adequate resection and anastomosis, there is little to be gained by the use of laparoscopy.60 In fact, the entire resection and anastomosis can often be performed via a limited left lower quadrant muscle splitting incision, a very small midline incision, or via a Pfannenstiel incision. If decompression is not possible, if the patient has signs and symptoms of peritonitis or colonic ischemia, or if gangrenous mucosa is visualized during attempted decompression, the situation becomes a surgical emergency. The patient should be rehydrated, electrolyte abnormalities and anemia should be corrected, the patient should be given intravenous antibiotics, and emergency surgery should be undertaken. The patient should be explored via a midline laparotomy, the volvulus should be manually reduced if the bowel is viable, and the redundant, twisted sigmoid should be resected. However, when gangrenous bowel is encountered during laparotomy, detorsion should not be performed. Accumulated toxins and bacteria may be released into the circulation, resulting in sepsis and cardiovascular collapse. Maintenance of the volvulus is therefore paramount as one obtains early vascular control. Inspection of the proximal colon must be performed, because in the face of a competent ileocecal valve, the closed loop obstruction produces rapid cecal ischemia and perforation.21,38 Obviously, avoidance of fecal contamination is paramount. With the use of 90-mm linear staplers, even though the bowel proximal to the volvulus may be enormously dilated, resection without spillage is usually possible. Generally, an anastomosis should be avoided if the proximal colon is massively dilated and loaded with feces. Some authors have applied the technique of intraoperative colonic lavage to facilitate primary anastomosis.61 In most cases, the proximal sigmoid should be exteriorized as an end-sigmoid colostomy; the distal end can be treated with a Hartmann-type closure, or a mucus fistula. A single prospective, randomized trial comparing primary anastomosis to the Hartmann’s procedure in 14 patients with gangrenous bowel, revealed a 50% anastomotic leak rate. In addition, mortality was more than double in those patients in whom an anastomosis was performed (33% versus 13%).36 Although the colostomy can generally easily be reversed in an elective manner, it must be recognized that because of the age and infirmity of many of these patients, in actual practice, the colostomy is often permanent. Overall mortality rates for the treatment of sigmoid volvulus range from 14% to 45%. Emergency surgery without preoperative detorsion is associated with mortality rates of 20%–45%. If nonviable bowel is encountered, these rates may exceed 50%. In fact, several studies report mortality of 60%–80% in these cases.9,17,21,35,36,38–41,62 Elective surgery, 295 after detorsion, is currently associated with mortality rates below 10%, despite the fact that these are generally patients with multiple comorbidities. However, older data reveal this mortality was as high as 25%.7,9,17,21,35,36,38–41,62 Paradoxically, outcomes in developed nations tend to be far worse than those in developing countries. This is presumed to be attributable to the older age and presence of significant comorbidities of the patients in the Western nations.4,38 Ballantyne,42 in a review of 67 series of sigmoid volvulus worldwide before 1981, compared mortality of nongangrenous and gangrenous bowel in the United States as compared with the rest of the world. He noted that the overall mortality in the United States was 25% and internationally 18%. When gangrenous bowel was present, the United States mortality further exceeded the international rate (80% versus 48%). However, for the nongangrenous, elective procedures, the United States mortality was somewhat less than the worldwide rate (10.6% versus 12.6%). It has been suggested that a nonresectional approach may be safer in these ill patients. However, nonoperative decompression alone carries 0%–12% mortality. This may be related to attempted detorsion in the presence of ischemic bowel. Finally, operative detorsion with or without pexy carries a similar mortality to elective resection and anastomosis (8%–14%). Therefore, one must consider the overall risk of recurrence as well as the risk of mortality. As expected, any nonresectional procedure carries a substantial risk of recurrence. For decompression alone it ranges from 25% to 70%, whereas detorsion, with or without pexy, has been associated with recurrence rates of 23%–40%. Most authors indicate that the risk of recurrence after resection approaches zero; it has been reported to be as high as 5% in some series.17,9,21,35,36,38–41,62 This is usually attributed to concomitant megacolon and/or megarectum.48 The only prospective randomized trial comparing elective resection and primary anastomosis with mesosigmoidoplasty confirms these findings. None of the resected patients and 29% of the plastied patients experienced recurrence. However, there was no mortality in the plasty group as compared with 10% in the resection group.36 Ileosigmoid Knotting Incidence and Epidemiology Ileosigmoid knotting, also called compound volvulus, is a rare form of volvulus uncommon in the West. It is, however, comparatively more common in certain areas of Africa, Asia, and the Middle East. In particular, large series are reported from Turkey, Russia, Scandinavia, Uganda, and India. It is more common in males than females, and presents at a younger age than sigmoid volvulus. In fact, it has rarely been reported in individuals older than 50 years of age.3,63–67 The geographic distribution corresponds with regions of the world where diets high in bulk and carbohydrates are 296 consumed with large volumes of liquid. The incidence is highest in groups in which one single large meal is consumed daily. It has been reported to peak in the followers of Islam during Ramzan when a single large meal is consumed at sunset after a full day’s fast.3,63–67 Pathogenesis/Etiology Theories of the pathogenesis of ileosigmoid knotting focus on a large volume diet high in bulk and carbohydrates, associated with large volumes of concomitant liquid ingestion. This may lead to an elongated abnormally mobile small intestinal mesentery, in addition to a long narrow pedicled sigmoid mesentery. The simultaneous consumption of a large meal combined with a large volume of fluid may then initiate an acute knot formation. As the bolus empties into the jejunum, the bowel becomes hyperperistaltic, and the weight acts to pull it into the left paracolic gutter. The empty distal loops of small bowel are then displaced around a narrow-based sigmoid. Continued peristalsis leads to further rotation of the loop, internal herniation, and knot formation (Figure 19-9). The fact that this entity usually occurs in the early morning hours lends further credence to the theory that dietary and dining habits of certain populations are causative.3,63–67 M.D. Hellinger and R.M. Steinhagen Alver et al.,64 in a review of 68 cases, described four different patterns of ileosigmoid knot formation which differentiate between an active or passive segment of bowel and the direction of rotation. Usually, the ileum is the active component and wraps around the sigmoid in either a clockwise or counterclockwise manner. Alternatively, the sigmoid may wrap around a passive segment of ileum, either clockwise or counterclockwise. Clinical Presentation The presentation of ileosigmoid knotting is one of acute onset, often with a fulminant course. There is a dramatic absence of prior similar attacks that are frequently seen in other forms of volvulus. Patients usually present in shock with signs of an intraabdominal catastrophe. The patient may complain of severe colicky abdominal pain, which begins in the periumbilical region. Nausea and vomiting, as well as distension, are early findings. At surgery, gangrenous intestine is found in 70%–100% of cases. As the result of the severity of the condition at presentation, acidosis, hypovolemia, oliguria, hypotension, and tachycardia are common findings.3,63–67 Preoperative diagnosis is extremely difficult because of the confusing nature of the presentation and unfamiliarity with FIGURE 19-9. Ileosigmoid knotting: these schematic illustrations indicate the four forms of knotting. The active ileum may rotate around the sigmoid colon in either a clockwise A or counterclockwise B direction. Much more infrequently, the sigmoid colon may act as the active loop and rotate in either a clockwise C or counterclockwise D direction around the ileum. 19. Colonic Volvulus this entity. Clinically, the patient’s condition presents as a small bowel obstruction, but radiographic evaluation is more consistent with a large intestinal obstruction. In fact, X-rays are often atypical, and the diagnosis is correctly made in fewer than 20% of patients preoperatively. However, several characteristic radiographic features of ileosigmoid knotting have been identified. These include a double obstruction, with an obstructed distended sigmoid loop pulled to the right and a proximal small bowel obstruction on the left. A diagnostic triad has been proposed consisting of a clinical small bowel obstruction, a radiographic large bowel obstruction, and the inability to pass a sigmoidoscope to decompress a suspected sigmoid volvulus.3,64–67 Treatment/Outcome Because of the high incidence of ischemia and gangrene at the time of presentation, after an initial period of rapid resuscitation and antibiotic administration, patients should be taken for emergent abdominal exploration. Controversy clearly exists regarding the preferred surgical approach. Treatment recommendations have ranged from simple detorsion to double resection. Because of the high likelihood of gangrenous bowel, most authors advocate en bloc resection of both segments of intestine without attempts to untwist the bowel. They state that untying the knot may be time consuming, difficult, hazardous, and may lead to systemic release of endotoxin and propagation of shock. Finally, perforation may ensue, leading to peritoneal contamination.3,63–66 However, others have recommended detorsion if one or both segments of bowel are thought to be viable. Deflation of the torsed segments had been shown to assist in untying the knot and diminishing the risk of rupture. There are conflicting data on recurrence after detorsion alone.3,63–66 Some authors advise resection of the sigmoid in all cases because of the possibility of recurrent knotting or eventual sigmoid volvulus.62,64–66 Although most perform a primary ileoileal or ileocolic anastomosis in patients with gangrenous small bowel, a Hartmann’s procedure is usually performed when the sigmoid is found to be nonviable. When the sigmoid is viable, despite the lack of bowel preparation, some authors have reported safe colorectal anastomoses. Because of the risk of inferior mesenteric artery or superior rectal artery thrombosis, most authors also advocate resection of the sigmoid well past the areas of twisting and/or gangrene to ensure adequate blood supply.3,63–67 Overall surgical mortality generally ranges from 30% to 50%. One review of seven patients reported no mortality, despite finding gangrenous colon in all seven patients, and gangrenous ileum in three.63–67 Mortality for nongangrenous bowel is generally less than that for gangrenous bowel. Reports range from 10% to 30% for nongangrenous intestine, and 40% to 50% for gangrenous bowel.3,64–66 Alver et al.,64 however, noted a paradoxic relationship between duration of symptoms and mortality. Those patients who presented within 297 24 hours had a mortality of 42%, whereas those that presented later had a much lower mortality rate of 20%. Additionally, he noted that the rate of gangrene was 91% in the early presenters but only 57% in the late presenters. This reflects the more rapid fulminant course of the patients that present earlier.64 In addition, when extensive gangrene of the small bowel is found, leaving the patient with less than 60 cm of residual bowel, mortality has been shown to be 100%.64 References 1. Tan PY, Corman ML. 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