Diverticular Disease

Most diverticula are situated in the sigmoid colon. Perforation of mesenteric diverticula is confined to the extraperitoneum or between the leaves of the sigmoid colon mesentery, causing an abscess or a phlegmon. Intraperitoneal perforation causing purulent or fecal peritonitis is uncommon. Krukowski and Matheson ¹ found that this type of problem was seen, on an average, less than once per year at the Lahey Clinic in Boston, twice per year at the Mayo Clinic, and seven times per year at Birmingham, United Kingdom. In a prospective study of acute diverticulitis treated throughout Australia and New Zealand, 248 patients were accepted for the survey. ² Of them, 214 had peritonitis: serous in 82 (38%), purulent in 104 (49%), and fecal in 28 (13%).

Carcinoma

Perforation from carcinoma of the colon and rectum is also uncommon. It occurs in 3.3 to 9.5% ^{3 , 4} of the cases. There are two types of perforation that may develop: perforation of the carcinoma itself and, less often, perforation of the colon proximal to the carcinoma, especially the cecum, which may occur from overdistention by air.

In the series of 1,551 patients by Mandava et al, ⁴ 51 (3.3%) presented with perforation, 61% had localized perforation with abscess, and 39% had free perforation. The site of perforation was most often at the carcinoma site (82%). In the remaining patients (18%), perforation occurred proximal to the obstructed primary lesion.

Ulcerative Colitis

Free perforation resulting from ulcerative colitis without toxic megacolon is unusual and usually occurs in the course of a severe attack of colitis, often during the initial attack itself. ⁵ Among the 1,928 patients with ulcerative colitis in one study, perforation of the colon was noted in only 5 (0.3%), mostly in the sigmoid colon. ⁵

Crohn’s Colitis

Free perforation resulting from small bowel Crohn’s disease is rare. In one series, it occurred in 1 to 2% of the cases. ⁶ Free perforation in a patient with Crohn’s colitis is even more unusual. A 10-year review at the Royal Infirmary of Edinburgh identified 198 patients diagnosed as having Crohn’s disease of the colon. ⁷ Six patients (3%) developed free perforation. Out of 679 patients with large bowel Crohn’s disease in the series from Oslo, Norway, 7 (1%) had free perforations. ⁵ The locations of intra-abdominal fistulas in patients operated on for complications of Crohn’s disease are listed in ▶ Table 35.1.

Toxic Megacolon

Toxic megacolon is a serious condition in which the inflamed colon becomes dilated, causing abdominal distention and serious illness. Although it is typically associated with ulcerative colitis, Crohn’s disease, other bacterial colitides, including Clostridium difficile colitis, are emerging as important causes of toxic megacolon. Delayed operative intervention may lead to perforation. In a series of 70 patients with toxic megacolon reported by Heppell et al, ⁸ 15 (21%) had sealed or free perforation.

Angiectasia

Prompted by the reports of small cecal vascular abnormalities by other authors, ^{23 , 24} Boley et al ²⁵ set out to study the blood vessels of the right colon in 1977. They found that in patients with a clinical and angiographic diagnosis of bleeding from colonic vascular lesions, the most consistent and apparently the earliest abnormality noted in all lesions was the presence of dilated, often huge, submucosal veins. The colonic mucosa overlying the lesion was very thin, often separated from the dilated vessels by a single layer of endothelium. Boley et al ²⁵ believed that the lesions were acquired vascular ectasias, resulting from degenerative changes that accompany aging. This theory accounts both for the higher incidence in older persons and for the multiplicity of lesions.

According to the authors’ concept, the direct cause of the ectasias is chronic, partial, and intermittent low-grade obstruction of the submucosal veins, especially where these veins pierce the circular and longitudinal muscular layers of the colon. This obstruction occurs repeatedly over many years during muscular contraction and distention of the cecum and the right colon. Because of the lower pressure within the veins, they can become occluded while higher arterial pressure maintains arterial inflow. Ultimately, repeated episodes of transiently elevated pressure within a submucosal vein result in dilatation and tortuosity of these vessels and later of the venules and capillaries of the mucosal units draining into it. Finally, as the responsible rings dilate, competency of the precapillary sphincters is lost, producing a small arteriovenous communication (▶ Fig. 35.1). The latter is for the “early” filling veins. Examination of colon resected from those patients older than 60 years without a history of gastrointestinal (GI) bleeding or obstruction found submucosal vascular ectasia in 53% and mucosal ectasia in 27% of specimen. These findings support the concept that these are degenerative lesions of aging in an older population.

Although aortic stenosis and GI bleeding have been noted and blamed as the cause of angiectasia, Boley et al ²⁵ believed that the low perfusion pressure from aortic stenosis might cause ischemic necrosis of the single layer of endothelium that often separates ectatic vessels from the colonic lumen. Angiectasia tends to cause slow repeated bleeding from the large bowel. Patients present with anemia or weakness. This is in sharp contrast to diverticular bleeding that is abrupt, more impressive, and less chronic. ²⁶ With increased awareness of angiectasia, more and more lesions have been recognized. Colonoscopy is a safe and effective test for making the diagnosis. ^{26 , 27}

Angiectasia can be recognized easily via colonoscopy as a distinct red mucosal patch consisting of capillaries (▶ Fig. 35.2). The size may vary from 2 mm to 1.5 cm. The histology of angiectasia shows tortuous and dilated capillaries in the lamina propria (▶ Fig. 35.3). Angiectasia discovered incidentally does not need to be treated. When angiectasias with active bleeding are found during colonoscopy in patients with massive lower gastrointestinal bleeding (LGIB), colon resection should be considered. Electrocoagulation can be performed, but the current bleeding is in the range of 40 to 50% with a significant risk of perforation. ²⁶ More than 70% of angiectasia was found in the right colon on colonoscopy, 22% in the descending and sigmoid colon, and 6% in the transverse colon in the series of 437 lesions studied by Jensen and Machicado. ²⁸

Diverticular Disease

Approximately 50% of the people older than 60 years have radiologic evidence of diverticula. Up to 20% bleed during their lifetime, and 5% have massive bleeding, which recurs in 25%, if the colon is not resected. ²⁹ Although most diverticula are in the sigmoid colon, 50 to 95% of bleeding diverticula are to the right of the splenic flexure. ^{30 , 31} Before the 1960s, it was thought that inflammation of the diverticula caused bleeding. Noer et al ³² were the first to note that most bleeding comes from noninflamed diverticula.

McGuire ³¹ studied 79 patients with severe bleeding diverticulosis and found that bleeding stopped spontaneously in 76%. Emergency operation was required in 24%. In patients who required no more than 3 units of blood transfusion on any day, 98.5% stopped spontaneously. In patients who required four or more transfusions on any day, 60% required emergency operation. In those patients who did not require operation, the recurrence rate was 38%, and in 79% of these patients, again, bleeding stopped spontaneously. Bokhari et al ³³ reported that of 115 elderly patients with a mean age of 79 years admitted to the hospital with bleeding diverticulosis and who required blood transfusion, 18% required colon resection. The postoperative mortality rate was 9%.

In the study of acute bleeding diverticulosis by Meyer et al, ³⁴ who used arteriographic and microangiographic techniques, the serial histologic sections revealed that the bleeding was the result of rupture of the vasa recta, which passed around the dome of the diverticulum. The vasa recta at the site of rupture had eccentric intimal thickening associated with thinning of the media and duplication of the internal elastic lamina. These arterial changes probably represent a nonspecific response to repeated arterial injury. The increased frequency of bleeding from the right-sided colonic diverticula remains a puzzling fact. Although the anatomic relationships of the vasa recta to diverticula are similar throughout the colon, one feature distinguishes right-sided from left-sided diverticula. Those on the right have wider necks and domes. Their vasa recta are, therefore, exposed over a greater length to any injurious factors arising from the colon. The nature of the injurious factors has not been determined yet. In addition, the true cause of the bleeding may be an unrecognized vascular ectasia. ³⁵

Carcinoma

Colonic bleeding is common with carcinoma of the colon and rectum, and ranges from a small amount of intermittent bright red rectal blood to chronic occult or gross bleeding causing anemia. The incidence of massive bleeding from a patient with colorectal carcinoma varies from series to series. In the series reported by Rossini et al, ³⁶ 311 patients with massive colonic bleeding underwent emergency colonoscopy; carcinoma caused the bleeding in 21%. Jensen and Machicado, ²⁸ using urgent colonoscopy, found that severe bleeding was caused by colorectal carcinomas and polyps in 11% of the patients. Leitman et al, ³⁵ using emergency arteriography, found carcinoma as the cause of massive bleeding in 10% of 55 patients.

Polyps

Although polyps of the colon and rectum are common, their causing massive bleeding is uncommon, with the incidence ranging from 2 to 10%. ^{28 , 35 , 36}

Ischemic Colitis

Ischemic colitis may be acute, transient, or agressive. ³⁷ The patient usually presents with bleeding per rectum, diarrhea, and abdominal pain; acute abdomen usually designates gangrene or perforation. In a series of 54 patients with massive lower GI hemorrhage who were undergoing emergency arteriography, Leitman et al ³⁵ found 3 patients with intestinal ischemia. Using urgent colonoscopy in 74 patients with severe hematochezia, Jensen and Machicado ²⁸ found no case of ischemic colitis. On the other hand, Rossini et al ³⁶ reported that 21 out of 311 patients with massive, active lower GI hemorrhage had ischemic colitis.

Inflammatory Bowel Disease

Ulcerative colitis is characterized by bloody diarrhea in more than 95% of the cases, but severe or massive hemorrhage is quite rare, occurring less commonly than other complications such as toxic megacolon, colonic perforation, or neoplastic degeneration. ³⁸ Nevertheless, massive hemorrhage occasionally represents the principal indication for emergency operation. The frequency of severe hemorrhage reported in the literature ranges from 0 to 4.5%. However, this relatively rare complication accounts for approximately 10% of all urgent colectomies for ulcerative colitis. ³⁵ In the series by Rossini et al, ³⁶ 45 of 311 patients (14%) with massive LGIB diagnosed by emergency colonoscopy had ulcerative colitis.

The incidence of massive bleeding in patients with Crohn’s disease has been reported as 1 to 13%. ³⁹ Active bleeding caused by Crohn’s colitis is uncommon. In the series reported by Robert et al, ⁴⁰ 21 of 1,526 patients (1.3%) with Crohn’s disease developed severe GI hemorrhage. The frequency of bleeding was significantly higher among patients with colonic involvement (17 of 929, 1.9%) than among those with small bowel disease alone (4 of 597, 0.7%). Primary bleeding episodes subsided without operation in 10 of 21 patients, but 3 of the 10 patients (30%) rebled massively. By contrast, primary excisional surgery was followed by recurrent hemorrhage in only 1 of the 11 cases (9%). Although the differences in mortality and in recurrent bleeding rates were not statistically significant, they favor surgical removal of the diseased bowel at the time of the first episode of massive hemorrhage. ⁴⁰ A review of literature by Cirocco et al ⁴¹ showed that operation was necessary to prevent life-threatening hemorrhage in 30 of 33 patients (91%).

Nasogastric Suction

The most common cause of massive GI bleeding remains peptic ulcer disease. All patients with GI hemorrhage should have a nasogastric tube placed in the stomach to rule out an upper GI source. If blood returns, a gastroduodenal source is confirmed. The nasogastric return must contain bile to rule out a bleeding duodenal ulcer. A bloody nasogastric aspirate has the highest specificity for high-risk lesions. A clear nasogastric aspirate reduces the possibility significantly. ⁴³ If any doubt remains, gastroduodenoscopy should be performed.

Proctoscopy

The rectum and anal canal can be examined quickly with a proctoscope to rule out a local source of the bleeding and to confirm the presence of blood proximal to the rectum. Most of the blood can be washed out, and an adequate examination can be usually done without much difficulty. Any active bleeding from a specific source in the anorectum can be treated with electrocautery or suture ligation.

Computed Tomography Angiography

Widespread availability and recent advances in CT have led to the development and validation of CT angiography (CTA) techniques. Sixty-four-row CTA allows thinner collimation, faster scanning times, greater anatomic coverage, and better multiplanar reformatted images, greatly expanding its diagnostic role for the evaluation of intestinal bleeding. ⁴⁴ With its widespread availability, CTA has largely supplanted ^99mTc-labeled red blood cell (RBC) scanning as the initial means of evaluating most patients presenting with acute LGIB who do not have a contraindication such as renal insufficiency or allergy to contrast dye. Besides the detection of active bleeding, CTA has the added advantages of being able to localize the site of bleeding and identify any coexisting pathology. A positive CTA should prompt further therapeutic efforts, such as angiographic embolization, or if the patient is showing signs of massive hemorrhage, targeted surgical resection of the culprit segment of intestine. The rate of bleeding able to be detected by CTA has been reported to be as low as 0.3 mL/min. ⁴⁵ The sensitivity of CTA for localization of a LGIB source is 91 to 92% when active bleeding is present, though it drops to as low as 45 to 47% when bleeding is intermittent. ⁴⁶ In a prospective trial, Ren et al found that CTA had an accuracy of 90.5% in the detection of active GI bleeding, and treatment planning was correctly established on the basis of CTA findings with an accuracy of 98.4%. Another prospective study comparing the diagnostic performance of CTA with angiography, colonoscopy, and surgical findings reported a sensitivity of 100%, specificity of 96%, positive predictive value (PPV) of 95%, negative predictive value (NPV) of 100%, and accuracy of 93%. ⁴⁷ A prospective trial published by Obana et al ⁴⁸ found that the detection rate of colonic diverticular bleeding by CTA alone was only 15.4%, but jumped to 46.2% when combined with colonoscopy. Nagata et al ⁴⁹ evaluated rates of detection of an LGIB source comparing early colonoscopy following urgent CTA with early colonoscopy alone and found that the detection rate was higher with colonoscopy following CTA than with colonoscopy alone for vascular lesions (35.7 vs. 20.6%; p = 0.01), leading to more endoscopic therapies (34.9 vs. 13.4%; p < 0.01). A major advantage of CTA in the evaluation of the patient with LGIB is its ready availability and ease with which the study can be performed and rapidly interpreted, leading to earlier and more targeted therapeutic intervention. It is a noninvasive study that does not require mechanical bowel preparation and carries very little risk. The main disadvantage is the small risk of contrast nephropathy, which may limit its use in patients with renal insufficiency.

Technetium-99 m Scintigraphy

The detection of colonic bleeding with nuclear medicine tracers depends on the intravenous infusion of technetium, which will stay within the blood pool for a reasonable period of time so that the source of the bleeding, which often is intermittent, can be detected. This procedure was first performed using sulfur colloid. However, because sulfur colloid collects in the liver and spleen, bleeding that occurs in the upper or middle abdomen such as in the stomach, duodenum, and transverse colon was often obscured. For this reason, RBCs labeled with technetium-99 m (^99m Tc) are now used. A small sample of the patient’s own RBCs is withdrawn, labeled with ^99mTc sodium pertechnetate, and reinjected. Scintigraphic images are then obtained in the hope of identifying the source of bleeding. Even if the patient is not bleeding at the moment of injection, bleeding over the next 12 or more hours can be detected by repeat scanning. With ^99mTc-labeled RBCs, bleeding at a rate of 0.1 mL/min can be detected (▶ Fig. 35.4). ³⁶ Nuclear medicine tracers are efficient for detecting bleeding that has slowed down and bleeding that is intermittent, but it requires several hours to follow the patient. RBC-tagged scanning is 30 to 90% accurate in localizing the bleeding point. ^{50 , 51} One of the major problems is that the tagged RBC study depends heavily on the technique and the radiologist. The poor results may be the result of an incorrect scanning interval because of the intermittent nature of bleeding or because the blood moves distally by peristalsis.

In the series by Nicholson et al, ⁵² the test sensitivity was as high as 97%, and the specificity was 85%. The predictive values were 94 and 92% when the scans were positive and negative, respectively. These impressive results are also shared by other authors. ^{53 , 54} Suzman et al ⁵⁴ emphasize using a delayed periodic scintigraphic imaging technique. In this technique, the images are acquired at 5-minute intervals for the first hour and at 15-minute intervals for up to 4 hours and stored in a dynamic mode. If needed, the patient is imaged every 90 minutes thereafter for up to 24 hours. Scan results demonstrating extravasation to tagged erythrocytes into the bowel lumen are read as positive. Fifty patients who required surgical intervention to control hemorrhage had a bleeding site confirmed by both clinical and pathologic examinations. Forty-eight of these patients (96%) had a bleeding site determined preoperatively. Of 37 patients with bleeding sites localized preoperatively by scintigraphy, 36 (97.3%) had correct localization based on surgical pathology. Only one patient required a subtotal colectomy solely because of nonlocalized bleeding. There was no recurrent postoperative bleeding, and there was no mortality in either operated or nonoperated patients.

Selective Mesenteric Arteriography

Selective mesenteric arteriography is an invasive method that can detect LGIB provided that the bleeding is active and brisk (0.5–1 mL/min) at the time of the test. Intermittent bleeding or minimal rates of bleeding may be missed by this method. In a patient with active bleeding, the contrast medium can be seen extravasated into the bowel lumen (▶ Fig. 35.5). Arteriography, when positive, can localize the site of the bleeding. The angiographic pattern of the vasculature may also suggest a malignancy, a diverticulum, a vascular malformation, or angiectasia. In a patient with massive and continuing bleeding, mesenteric arteriography should be used as the primary test, provided that the facilities for the technique are available and can be mobilized quickly. Another important advantage of mesenteric arteriography is its potential therapeutic applications. It is important to adequately resuscitate the patient with adequate intravenous fluid and blood transfusion to maintain good blood pressure. Once the bleeding site is detected, the transcatheter treatment using a vasopressin drip or emboli can be accomplished. ³⁵ If successful, it may convert an emergency exploratory celiotomy into an elective one, or it may avert an operation altogether (▶ Fig. 35.6). The action of vasopressin is twofold. It produces both arteriolar contraction and bowel wall contraction, which help stop the bleeding. ^{55 , 56}

However, the use of selective vasoconstrictive agent infusion is associated with high recurrence rates and complication of ischemia of the GI tract. Recently, improved microcatheters that allow selective cannulation of secondary vessels and embolization agents such as polyvinyl alcohol (PVA) and metal coils have been used with much greater success.

The incidence of ischemia has markedly decreased due to the use of larger PVA or metal coils and increased experience. Most series since 1997 reported ischemia that required resection of less than 5%. ⁵⁵

Khanna et al ⁵⁵ conducted a meta-analysis of 25 identified publications reporting the use of embolization and an unpublished series of 12 consecutive patients with LGIB from their own institution. Six published series and the authors’ series met selection criteria for the analysis. The results showed that embolization for diverticular bleeding was successful in 85% of patients (no recurrence after 30 days). In contrast, rebleeding after embolization for angioectasia and other nondiverticular bleeding occurred in 45%.

Angiographic evidence of angiectasia included clusters of small arteries frequently located along the entire mesenteric border of the cecum and ascending colon, a vascular tuft (representing the degeneration of mucosal venules), and an early filling vein (▶ Fig. 35.7). Because the natural history of ectasias is one of recurrent bleeding, Boley et al ⁵⁷ recommended that all patients who have bleeding and have an ectasia demonstrated by angiography should undergo colonic resection. It is difficult to determine the frequency of bleeding in patients with diverticular disease and angiectasia, because both occur in the elderly and often the bleeding stops during angiography or colonoscopy.

One advantage of angiography as opposed to scintigraphy or colonoscopy for this particular patient population is that no special preparation is necessary such as labeling of erythrocytes and bowel cleansing. Even hemodynamically unstable patients can be studied while resuscitation efforts are under way, including the administration of intravenous fluids and/or blood products. It is critical that no oral contrast agents be administered before angiography because it may obscure subtle bleeding. ⁵⁸

Urgent Colonoscopy

The use of a colonic lavage (GoLytely or CoLyte) as a gut cleanser has opened a new approach to colonic bleeding. In the hands of a growing number of physicians, urgent colonoscopy has become the first choice of investigative modality in the diagnosis and therapy of massive colonic bleeding. As soon as the patient has been resuscitated and upper GI bleeding has been ruled out, GoLytely or CoLyte is rapidly instituted via the nasogastric tube or orally. The entire colon can be cleansed within 2 hours. Alternatively, oral Phospho-soda can be administered to accomplish the same goal. Colonoscopy can be performed immediately. In a series reported by Jensen and Machicado, ⁵⁹ in 80 consecutive patients with severe, ongoing rectal bleeding (mean, 6^– units of transfused blood) from an unknown source, urgent colonoscopy was performed after oral purge. In all cases, the cecum was reached. Seventy-four percent of the patients had bled from the colon (angiomas, 30%; diverticulosis, 17%; polyps or carcinomas, 11%; focal ulcers, 9%; others, 7%), 11% had upper GI lesions, and 9% had presumed small bowel lesions. In only 6% was the cause of bleeding not identified. No complications resulted from colonoscopic hemostatic procedures, although four patients had clinically significant fluid overload and early heart failure during the cleansing procedure. Rossini et al ³⁶ performed 409 emergency colonoscopies for massive colonic bleeding. The sites and causes of bleeding were found in 311 cases (76%). There was a wide range of causes of the bleeding (▶ Table 35.2). In 85% of the cases, the bleeding was in the left colon, 4% in the transverse colon, and 11% in the right colon. Only two patients had complications: one developed increasing hemorrhage from ulcerative colitis and one developed diverticulitis. There was no perforation.

One of the greatest advantages of successful colonoscopy is its providing an access to therapy. Colonoscopic hemostatic techniques can be divided into two categories: nonthermal and thermal modalities. The nonthermal techniques involve injection of vasoconstricting agents such as a dilute epinephrine solution and vasodestructive agents alone or in combination with such agents as absolute alcohol, morrhuate sodium, and sodium tetradecyl sulfate. A wide variety of thermal modalities, including electrocoagulation, laser photocoagulation, and heater probe coagulation, are available.

Urgent colonoscopy for massive colonic bleeding has emerged as a practical and efficient method to diagnose and control some causes of colonic bleeding. The GI bleeding team established at the Mayo Clinic on October 1, 1988, provides a very useful team approach to the treatment of GI bleeding. The bleeding-team contact begins within an hour of the patient’s clinical presentation. The triage team determines whether the patient should be admitted to the intensive care unit or whether the team should proceed with evaluation, deciding on the timing of colonoscopy. Emergency colonoscopy is performed after a rapid (1- to 2-hour) lavage with GoLytely or CoLyte. ⁶⁰ Several lessons can be learned from this study. A total of 417 patients were evaluated. Fifty-six percent of the patients were seen from 8 a.m. to 5:00 p.m., 34% from 5:00 p.m. to 12 a.m., and 10% from 12 a.m. to 8 a.m. Of the 417 patients, 56% developed bleeding during hospitalization. Upper GI bleeding accounted for 82%. The five most common etiologies included gastric ulcers (83 patients), duodenal ulcers (67 patients), gastric erosions (41 patients), esophageal varices (35 patients), and diverticulosis (29 patients). Nonsteroidal anti-inflammatory drugs (NSAIDs) were implicated in 53% of gastroduodenal ulcers.

Twenty-nine patients with bleeding diverticulosis involved the oldest patient group, with an average age of 77 years. Diverticula were limited to the left colon in 52% (15 patients). Eventual cessation of bleeding was commonplace and occurred in 27 patients (93%). Four patients (14%) experienced rebleeding during the hospitalization. Only one patient required operation for rebleeding.

From the Mayo Clinic study, it is unclear whether urgent colonoscopy for acute colonic bleeding will alter outcome, especially if majority of the bleeding is from diverticulosis. The very high rates of spontaneous cessation, the low relative transfusion requirements, and absent mortality argue for initial observation as an appropriate and cost-effective approach. Colonoscopy might more appropriately be performed on an elective basis.

With the better technique of RBC-tagged scan, using dynamic scanning technique, the very high accuracy of both the detection of GI bleeding and the localization of the site of bleeding has made it the choice as the primary test. ^{54 , 61} Another advantage of RBC-tagged scanning is that when the scan is negative, those patients (7.3%) rarely require operative intervention. ⁵¹ At the present time, it appears that the trend has shifted from urgent or emergent colonoscopy to an emergency RBC-tagged scan or selective mesenteric arteriography as the primary test for acute LGIB. ^{54 , 55}

Exploratory Celiotomy

Determining when to operate on patients with massive and continuous colonic bleeding requires astute clinical judgment. Generally, an exploratory celiotomy is considered seriously when a patient requires 5 units of blood transfused within 24 hours or less, if the patient’s condition deteriorates. Ironically, greater aggressiveness in deciding to operate earlier is appropriate in treating older and unfit patients. Patients who have recurrent active bleeding that has stopped spontaneously or after nonoperative treatment also should undergo an operation.

Known Bleeding Site

A segmental resection is indicated when the site of bleeding is known, whether the knowledge comes from scintigraphic, arteriographic, or colonoscopic information. The rate of recurrent bleeding after definitive resection has ranged from 0 to 11% (average, 4%), and the reported operative mortality rate has ranged from 0 to 22% (average, 10%). ^{36 , 62 , 63 , 64 , 65 , 66}

Unknown Bleeding Site

It is not uncommon that despite all the efforts and the availability of modern technology, the site of the bleeding is still not ascertained and the bleeding continues. Under these circumstances, exploratory celiotomy should be performed. The entire GI tract must be examined carefully for abnormalities. Small bowel lesions such as leiomyoma, lymphoma, and those of Crohn’s disease are occasional sources. If they are not present, an intraoperative endoscopy should follow. A sterilized colonoscope is introduced via an enterotomy in the proximal jejunum. An alternative is to pass a clean but nonsterilized colonoscope through the mouth into the stomach and duodenum. The surgeon then guides the scope throughout the entire small bowel into the cecum. The entire small bowel mucosa is examined. At the same time, the surgeon can examine the bowel by transillumination. ^{67 , 68} Angiectasia can be recognized by its abnormal vasculature. If these are found, they can be ligated with interrupted sutures. Other abnormalities can also be effectively visualized. ⁶⁹ If colonoscopy has not been accomplished preoperatively, an intraoperative colonoscopy also should be performed.

When intraoperative endoscopy or thorough examination of the entire GI tract is negative and evidence points to colonic bleeding at an unknown site, a subtotal colectomy is performed. Some investigators have argued that blind segmental resection of the right colon may be a better surgical option than blind total colectomy, especially if there are suggestions of right-sided bleeding such as blood primarily in the right colon. This argument is strengthened by a negative preoperative examination of the left colon. Blind right hemicolectomy has had the lowest mortality (less than 5%), and the lowest frequency of rebleeding among segmental resections, and it does not incur the risk of incontinence or diarrhea, especially in elderly patients. ⁶⁶ However, the risk of rebleeding is still significant, and the author feels more confident with a total abdominal colectomy. Farner et al ⁷⁰ conducted a retrospective study comparing 50 limited colon resections to 27 total/subtotal colon resections for acute LGIB (receiving two or more units of packed RBCs). They found that recurrent bleeding after the operation was more common in the limited colon resection group (18 vs. 4%; p < 0.05).

Torrential LGIB from an unknown site should be explored as soon as possible. If there is no obvious source of bleeding in the small intestine, a total abdominal colectomy should be performed. The recurrent bleeding has ranged from 0 to 6%, and the mortality rate from 0 to 50% (average, 22%). ^{34 , 53 , 62 , 66 , 71 , 72 , 73 , 74} Because most of the high morbidity and mortality are from anastomotic leaks, ^{73 , 74 , 75} an anastomosis should not be performed in this circumstance. Another risk factor is the delay of surgery. The operation should be performed before 10 units of blood are needed. ⁷⁴ A schematic approach to massive colonic bleeding is shown in ▶ Fig. 35.8.

Bleeding

Early postoperative bleeding, which is usually the result of a technical error, is not common. The most common source is from the external hemorrhoidal area and is easily detected and controlled by placement of a suture. The suturing can be performed at bedside or in a treatment room with local anesthetic used. In other cases, the patient should be returned to the operating room, where the anorectum is examined with the patient under local, regional, or general anesthesia. Acute bleeding from the anal canal usually is from insecure suture ligation of the hemorrhoidal pedicles.

Severe Anal Pain

For most patients, the pain following anorectal operations is moderate and requires analgesics during the first 1 to 2 postoperative days. Intolerable pain despite adequate analgesics is uncommon. However, because such pain may be a sign of a perianal hematoma, inspection of the anal wound is required. Even a light dressing around the anus may aggravate the pain, and so it should be removed a few hours after the operation. Anorectal packing has no place in modern anorectal surgery. Warm heat directed toward the perineum will help relieve the pain during the first 24 hours after operation. The next day, warm sitz baths can be used as treatment. Most pain following hemorrhoidectomy comes from anal sphincter spasm. Another source of pain is the closure of the anoderm and anal verge with tension. It is better to leave the wound open than to close it with tension.

Anal dilatation does not reduce postoperative hemorrhoidal pain and risks incontinence. ⁷⁶ The use of multimodality techniques with long-acting analgesics (i.e., liposomal bupivacaine) and acetaminophen and nonsteroidal drugs as described in Chapters 5 and 6 has diminished this problem.

Urinary Retention

To minimize urinary retention, a preoperative assessment with good history taking will identify patient with voiding problems such as prostatic hypertrophy and urethral stricture. These should be corrected prior to embarking on an elective rectal procedure. Urinary retention after hemorrhoidectomy is common, but it is unusual following fistulotomy and lateral internal sphincterotomy. Following hemorrhoidectomy, urinary retention has been reported to be as low as 3.5 to 10% if the patient is given a limited amount of intravenous fluid during the operation. ^{77 , 78} A retrospective review of 1,026 patients who underwent anal operative care over a 5-year period at the Mayo Clinic revealed a urinary retention rate of 34% for hemorrhoidectomy, 4% for internal sphincterotomy, 5% for incision and drainage of perianal abscesses, and 2% for fistulotomy. ⁷⁹ Anorectal surgery may dull the sacral parasympathetic nerve fibers controlling contraction of the detrusor muscle of the bladder. Pain from surgery may stimulate the sympathetic nerve to the urethral sphincter, causing spasms. ⁸⁰

The rationale of fluid restriction is to avoid distention of the bladder for as long as possible because many patients are unable to void for several hours after anorectal operations. Friend and Medwell ⁸¹ have shown that for hemorrhoidectomy in an outpatient setting, urinary retention is uncommon (1%) and that it is not related to the amount of the fluid given during the procedure. The type of anesthesia does not seem to affect urinary retention. The reason for the low incidence of urinary retention in the outpatient setting is unclear, but could involve the psychological effect of the home or hotel environment. The authors believe that if the incisions are not beyond the anorectal ring, urinary retention is uncommon. The rare urinary retention is observed in a transsphincteric fistulotomy in which pain is significant, whereas the frequent urinary retention is observed in a transanal excision of low rectum in which there is almost no pain.

Avoiding catheterization, unless the bladder is markedly distended, is the goal. However, excessive bladder distention may cause damage. A single episode of overdistention of the bladder produces chronic changes of irreversible damage to the detrusor muscle. ⁸² Avoidance of acute bladder overdistention by the judicious use of sterile intermittent catheterization in the postoperative period would appear to involve a low risk of inducing bacteremia and may prevent bladder decompensation. ⁸³ Using bethanechol chloride (Urecholine) to stimulate the detrusor muscle does not help prevent or correct urinary retention after hemorrhoidectomy. ^{84 , 85} Similarly, using prazosin, an alpha-adrenergic blocker, to release the bladder neck spasm is also not effective. ⁸⁶

For practicality, all patients should void just before undergoing operation. The intravenous fluid during surgery as well as the first few hours after the operation should be limited to 300 mL. Patients should not be pushed or rushed to void, which may cause anxiety. Anal dressing should be removed and a pad used instead.

Infection

It is common for a patient to have a transient low-grade fever after anorectal operations, particularly hemorrhoidectomy, during the first 1 to 2 days as a response to the anal wound. Despite an unprepared bowel and the fecal load, abscess formation following anorectal operations is rare. In a series of 500 closed hemorrhoidectomies reported on by Buls and Goldberg, ⁷⁸ there were no abscesses recorded. In a study by Bonardi et al, ⁸⁷ 36 patients had serial blood drawn every 6 hours for 24 hours after hemorrhoidectomy; 39% of the patients developed a fever above 99 °F (37.2 °C) in the first 6 hours, 67% between 99 °F (37.2 °C) and 101 °F (38.3 °C), and one patient had a temperature higher than 101 °F (38.3 °C). Three patients (8%) had positive blood cultures in the immediate postoperative samples but none in the subsequent samples. The significance of fever and bacteremia after hemorrhoidectomy is probably trivial because none of the patients developed further septic complications.

In patients with high fever, other signs of sepsis such as chills, leukocytosis, malaise, and jaundice may be signs of serious complications. Parikh et al ⁸⁸ reported that two cases of liver abscesses occurred within 1 week after an uncomplicated hemorrhoidectomy. In both cases, the diagnosis was confirmed by CT scan of the abdomen and both were successfully treated with CT-guided percutaneous drainage and antibiotics. The bacteria found were Streptococcus viridans, Peptostreptococcus, and Klebsiella pneumoniae. Pyogenic liver abscess after hemorrhoidectomy is extremely rare. Only four cases have been reported. It is important to be aware of the possibility, because the mortality rate of undrained liver abscesses is between 94 and 100%. Even with treatment, the mortality rate reached 20%.

Delayed complications are defined as those that occur more than 1 week after the operation. These include bleeding, fecal impaction, wound abscess, incontinence, stricture, skin tags, ectropion, mucosal prolapse, and the unhealed wound. Most patients would have been discharged from the hospital by the time they present.

Bleeding

Delayed massive bleeding occurs in 0.8 to 4% of patients after hemorrhoidectomy, usually between 4 and 14 days. ^{78 , 89 , 90} The rate of occurrence is much lower for other anorectal procedures. It has been speculated that the bleeding is caused by the breakdown of the granulating wound during defecation or by infection disrupting the blood vessels and the pedicle of the wound in the anal canal. The patient should be admitted to the hospital and given appropriate intravenous fluids. Patients may be hypotensive, and some may require blood transfusions. ⁹⁰ Of note is that one-third of patients with post-hemorrhoidectomy bleeding were being anticoagulated with medication such as acetylsalicylic acid (ASA), NSAIDs, or warfarin (Coumadin) in the series reported by Rosen et al. ⁹⁰

Most bleeding stops after bed rest. If bleeding continues, some surgeons have used a 30-mL balloon bladder catheter to create a tamponade of the anal canal. ⁹¹ However, this method is crude and may cause severe anorectal pain. Rosen et al ⁹⁰ successfully treated delayed post-hemorrhoidectomy bleeding with packing in 20 of 20 patients. They used a rolled, slightly moistened absorbable gelatin sponge (Gelfoam) packing in the anal canal. However, late complications requiring reoperation developed in 15%.

Another option is taking the patient to the operating room, where the anal canal can be explored with the patient under local, regional, or general anesthesia. Hemostasis is controlled with 3–0 Vicryl or Dexon sutures. Frequently, after all blood clots have been removed, the bleeding point cannot be identified except for a friable anal wound. In these situations, a deep stick-tie should be placed at the pedicle of the anal wound; if oozing blood is noted, the suture line should be redone. Besides providing an immediate control of bleeding, cleaning the anorectum stops the patients from passing old blood, which often makes it difficult to tell whether the bleeding has stopped.

High-risk patients for postoperative bleeding include those on chronic hemodialysis or anticoagulants. Sheikh et al ⁹² performed these anorectal procedures in 18 patients with chronic renal failure, who were undergoing hemodialysis. Two patients developed postoperative hemorrhage. Only one of them required surgical hemostasis in the operating room on the third postoperative day. None of the patients had delayed wound healing. The authors recommend certain measures to minimize the problems. The final preoperative dialysis should be performed within 24 hours. The bleeding diathesis in patients with chronic renal failure is due to a platelet defect that is corrected by dialysis. They recommend a template bleeding time assessment in addition to standard prothrombin time and partial thromboplastin time testing. Profound anemia (average, 6.1 g/dL in this series) is generally well tolerated by these patients. Preoperative transfusions to raise the hemoglobin level are usually unnecessary and even inadvisable, because transfusion subjects the patient to risk of potassium administration, congestive heart failure, and hepatitis. Intraoperative fluid administration should be severely restricted, and solutions containing potassium avoided. Arteriovenous fistula thrombosis is a frequent and troublesome complication requiring careful positioning of the involved area during surgery. Infusion or measuring blood pressure in that arm should be avoided. It is desirable to delay hemodialysis in the immediate postoperative period because heparin is required for the extracorporeal circuit. ⁹²

Fecal Impaction

Many patients develop constipation after anorectal procedures, particularly hemorrhoidectomy, partly because of the fear of pain and the lack of the urge to defecate. Patients who require a large amount of analgesics, particularly morphine, are also prone to constipation. Codeine is contraindicated in anorectal surgery because it severely disturbs the motility of the GI tract. Prevention of constipation is the best treatment. Eating plenty of fruits and vegetables along with other high roughage foods is ideal advice. Psyllium seed preparations may not prove beneficial for all patients, especially if such preparations have not been prescribed preoperatively. Laxatives should be given early usually on the first postoperative day, and the dosage should be increased gradually to the maximum until the patient has a good bowel movement. Polyethylene glycol (17 g orally once or twice a day in fluid) assists in keeping the stool soft.

Fecal impaction may be difficult to diagnose in the postoperative period. Usual symptoms are increasing pain or pressure in the perineum and sometimes diarrhea from overflow of stool around the impaction. Pain out of proportion is a good indication of fecal impaction. Digital rectal examination will reveal a fecal bolus in the anorectum. If the pain is severe, the surgeon may use a small cotton swab lubricated with KY jelly instead of the finger. If the patient has fecal impaction, and laxatives and enemas have failed to work, it may be necessary to evacuate the impaction in the operating room with the patient under anesthesia. Tap water or other kinds of enemas often do not work in that situation because water cannot be passed into the rectum.

Fecal impaction is a serious complication following anorectal operations. Fortunately, it is uncommon. Impaction occurs in only 0.4% of patients, usually after hemorrhoidectomy. ⁷⁸ The low incidence should be credited to careful attention to bowel movements after anorectal operations, a common practice among colorectal surgeons.

Anal Wound Abscess

Despite continuing fecal contamination after operation, abscess in the anal wound is rare. In a report on 500 patients who underwent closed hemorrhoidectomy, Buls and Goldberg ⁷⁸ recorded no abscesses. Walker et al ⁹³ reported a perianal abscess in 2% of 306 patients, following internal sphincterotomy for anal fissure and anal stenosis.

Fecal Incontinence

Most patients experience some degree of incontinence, particularly of gas and liquid stool, after anorectal procedures for anal fissure, fistula-in-ano, and hemorrhoids. Anal sensation is partially impaired, leading to some degree of incontinence in up to 50% of patients after hemorrhoidectomy, but it usually resolves within 6 weeks. ⁹⁴ Persistent incontinence after operation for a transsphincteric or extrasphincteric fistulotomy may be improved by a sphincteroplasty (see Chapter 14).