Practice guidelines

Management of the Adult Patient With Acute LowerGastrointestinal Bleeding

Gregory Zuccaro, Jr., M.D.,Department of Gastroenterology, Cleveland Clinic Foundation, Cleveland, Ohio

I. PREAMBLE

Guidelines for clinical practice are intended to suggestpreferable approaches to particular medical problems asestablished by interpretation and collation of scientificallyvalid research, derived from extensive review of publishedliterature. When data are not available that will withstandobjective scrutiny, a recommendation may be made basedon a consensus of experts. Guidelines are intended to applyto the clinical situation for all physicians without regard tospecialty. Guidelines are intended to be flexible, not neces-sarily indicating the only acceptable approach, and shouldbe distinguished from standards of care that are inflexibleand rarely violated. Given the wide range of choices in anyhealth care problem, the physician should select the coursebest suited to the individual patient and the clinical situationpresented.

These guidelines are developed under the auspices of theAmerican College of Gastroenterology and its Practice Pa-rameters Committee. These guidelines are also approved bythe governing boards of the American GastroenterologicalAssociation and the American Society for GastrointestinalEndoscopy. Expert opinion is solicited from the outset forthe document. Guidelines are reviewed in depth by theCommittee, with participation from experienced cliniciansand others in related fields. The final recommendations arebased on the data available at the time of the production ofthe document and may be updated with pertinent scientificdevelopments at a later time.

II. DEFINITIONS

In most review articles on this topic, acute lower gastro-intestinal bleeding refers to:

1. blood loss from the gastrointestinal tract of recentonset

2. emanating from a location distal to the ligament ofTreitz

3. resulting in instability of vital signs, anemia,and/or need for blood transfusion

This definition is not useful for the purpose of a practiceguideline. The source of acute gastrointestinal bleeding isnot always apparent from initial history and physical exam-ination. The acute onset of hematochezia is the most com-mon clinical presentation of acute lower gastrointestinalbleeding, necessitating hospitalization and immediate eval-uation and management. This guideline will focus on theevaluation of hematochezia associated with instability ofvital signs, anemia, and/or need for blood transfusion. Thelimitations in this definition are recognized, as the source ofbleeding in a subset of patients with hematochezia will befrom the upper gastrointestinal tract, and melena in somepatients will be due to a source distal to the ligament ofTreitz.

This guideline is not intended for patients presenting withstool that is positive for occult blood, chronic bleeding ofobscure origin, or obvious self-limited bleeding where thelikelihood of a change in vital signs or anemia is low (e.g.,anal outlet bleeding). An algorithm outlining the approachto the adult patient with acute lower gastrointestinal bleed-ing is presented in Figure 1.

III. INITIAL EVALUATION

A focused history and physical examination is essential inthe initial evaluation of the patient with acute lower gas-trointestinal bleeding. Initial laboratory testing should in-clude measurement of complete blood count, electrolytes,type and crossmatch, and coagulation profile.Historical points to be recorded include:

the nature and duration of bleeding, including stoolcolor and frequency

associated symptoms, including abdominal pain, recent

Prepared for the Practice Parameters Committee of the AmericanCollege of Gastroenterology.

Received Dec. 5, 1997; accepted Apr. 10, 1998.

THE AMERICAN JOURNAL OF GASTROENTEROLOGY Vol. 93, No. 8, 1998Copyright 1998 by Am. Coll. of Gastroenterology ISSN 0002-9270/98/$19.00Published by Elsevier Science Inc. PII S0002-9270(98)00276-7

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change in bowel habits, fever, urgency/tenesmus,weight loss

relevant past history, including previous bleeding epi-sodes, trauma, past abdominal surgeries, previous pep-tic ulcer disease, history of inflammatory bowel dis-ease, history of radiation therapy to the abdomen andpelvis, and prior history of major organ dysfunction(including cardiopulmonary, renal, and liver disease)

current/recent medications (including NSAIDs, aspirin,and anticoagulants), and allergies.

presence or absence of chest pain/palpitations, dyspneaat rest or on exertion, lightheadedness, or posturalsymptoms.

Physical examination should include (at a minimum): immediate recording of vital signs with postural

changes. A drop of .10 mm Hg or an increase of .10

beats/min in pulse is indicative of acute blood loss of.800 ml (15% of total circulatory blood volume).Marked tachycardia and tachypnea, associated withhypotension and depressed mental status is indicativeof a blood loss of .1500 ml (30% circulatory bloodvolume) (1, 2).

cardiopulmonary, abdominal and digital rectal exami-nation.

Initial laboratory studies should include:

measurement of complete blood count; it should beremembered that initial hemoglobin/hematocrit valuemay not reflect the degree of blood loss due to volumecontraction, and may fall significantly after hydration.

serum electrolytes, blood urea nitrogen, and creatinine.In upper gastrointestinal bleeding, the serum blood ureanitrogen may rise without a commensurate rise in se-

FIG. 1. Algorithm for lower GI bleeding.

AJG August 1998 MANAGEMENT OF ACUTE LOWER GI BLEEDING 1203

rum creatinine. This appears to be due to absorption ofproteins from blood in the gastrointestinal tract, andfrom dehydration (35). However, the absence of a risein blood urea nitrogen does not rule out an uppergastrointestinal source.

coagulation profile (PT/PTT), particularly if there isany history of liver disease or if the patient has beentaking anticoagulant medication

type and crossmatch electrocardiogram for patients .50 yr of age, younger

patients with risk factors for coronary artery disease orhistory of dysrhythmia, or patients with chest pain/palpitations associated with the bleeding episode

Resuscitative measures and an appropriate level of patientmonitoring must be established before diagnostic testing orspecific therapeutic intervention. Intensive monitoring andcare is appropriate for the patient with instability of vitalsigns not responding to initial resuscitative measures. Initialadmission to an intensive care unit is also appropriate forthe patient at risk for complications from comorbid illness.

The goal of resuscitation is the restoration of euvolemiaand resultant stability in vital signs. Resuscitative measuresinclude initial fluid administration via large bore intrave-nous catheters. The amount of transfusion of red blood cellsand blood products must be individualized. There are po-tential adverse effects of blood transfusion; the goal oftransfusion should be to minimize the risk of complicationsdue to red blood cell loss and/or correction of coagulopathy,and not to transfuse to an arbitrary level of hemoglobin/hematocrit.

The treating physician must consider several factors when

determining the immediate disposition of the patient (i.e.,admission to intensive care unit, monitored bed, regularhospital bed, clinical decision unit, or outpatient manage-ment). Kollef et al. stratified patients with acute upper orlower gastrointestinal bleeding into low risk and high riskfor adverse outcomes during the hospitalization. Among thecharacteristics of the group at high risk for adverse out-comes were: a greater prevalence of comorbid illness (renal,hepatic, pulmonary, hematological, neurological, or cardi-ac), a lower serum albumin, a higher prothrombin time, anda higher serum bilirubin (6). Admission to the intensive careunit or other monitored setting is appropriate for thoseindividuals not responding to initial resuscitation measures(i.e., persistent hypotension/tachycardia and need for trans-fusion). Thibault et al. reported on a total of 2693 consec-utive patients admitted to an intensive care unit. Four per-cent of admissions were for gastrointestinal hemorrhage.Patients remained in the intensive care unit for an average of3 days, and in the hospital an average of 15 days. In hospitalmortality for this group was 15%. The authors stress the roleof the intensive care unit not only for the patient requiringacute intervention, but for monitoring and the early detec-tion of clinical deterioration (7). Initial monitoring in anintensive setting is reasonable for the patient with signifi-cant comorbid illness, even if vital signs have stabilizedwith initial resuscitation.

IV. DETERMINATION OF THE SOURCEOF BLEEDING

Some of the common etiologies for acute gastrointestinalbleeding with hematochezia are listed in Table 1. In most

TABLE 1Lesions Frequently Encountered in Evaluation of Hematochezia

Lesion Frequency(From Ref 8, 9)* Comments

Diverticular disease 1740% Stops spontaneously in 80% of patients In one series, surgery was unlikely if ,4 U red cell transfusion

given in 24 h, but required in 60% of patients receiving .4 U in24 h (10)

Colonic vascular ectasia 230% Frequency of these lesions vary widely in clinical series Acute bleeding appears to be more frequently due to lesion in

proximal colon (9)Colitis (ischemia, infectious, inflammatory bowel

disease, radiation proctopathy)921% Ischemic colitis often presents with abdominal pain and self-limited

hematochezia. Colitis is segmental, most often affecting splenicflexure (11)

Bloody diarrhea is most frequent symptom of infectious colitis andinflammatory bowel disease of the colon

Colonic neoplasia/post-polypectomy bleeding 1114% Postpolypectomy bleeding is frequency self-limited, and may occur#14 days after polypectomy (12)

Anorectal causes (including hemorrhoids, rectalvarices)

410% Anoscopy/proctoscopy should be included in the initial evaluationof these patients

Upper gastrointestinal sites (including duodenal/gastric ulcer, varices)

011% A negative nasogastric aspirate does not exclude this possibility(see text)

Small bowel sites, including Crohns ileitis, vascularectasia, Meckels diverticula, tumors

29% Frequency diagnosed by radiologic studies or enteroscopy after theacute bleeding episode has resolved

* Two recent (1997) comprehensive reviews on this topic.

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clinical series, the majority of patients presenting with he-matochezia are .60 yr. Whereas the recommendations forstructural evaluation below can be applied to most clinicalsituations, there are circumstances in which it is appropriateto alter the order of tests to focus on a highly likely cause forbleeding. For example, for the patient in the third or fourthdecade of life presenting with maroon colored stool, eval-uation for a Meckels diverticulum might be performed veryearly in the structural evaluation. A patient with hematoche-zia who had undergone colonoscopy and removal of asigmoid colon polyp 3 days previously may require nostructural evaluation if bleeding stops spontaneously.

In the patient with hematochezia, an upper gastrointestinalbleeding source must be considered. A nasogastric aspirateshowing copious amounts of bile and negative for bloodmakes an upper gastrointestinal source unlikely. Uppergastrointestinal endoscopy should be performed if the re-sults of nasogastric aspiration shows evidence of uppergastrointestinal bleeding, or is negative for blood and bile.

Patients with hematochezia most frequently bleed from acolonic source. However, when bleeding is brisk, an uppergastrointestinal source of bleeding may present as hema-tochezia. In a clinical series by Jensen and Machicado, 11%of patients initially suspected of having lower gastrointes-tinal bleeding actually had an upper gastrointestinal source(13). Placement of a nasogastric tube should be performedin patients with hematochezia. The presence of a bloodyaspirate confirms the presence of upper gastrointestinalbleeding. The absence of blood does not rule out uppergastrointestinal bleeding, as blood from a duodenal sourcemay not reflux into the stomach. Luk et al. found thatnasogastric aspiration was 98% accurate in detection ofbleeding duodenal ulcers (14). Cuellar et al. performednasogastric aspiration just before endoscopy in 62 patientswith apparent upper gastrointestinal hemorrhage. One of 18patients (6%) with a nonbloody, yellow-green aspirate hada duodenal ulcer at endoscopy (15). In the aforementionedseries from Jensen and Machicado, nasogastric aspirationwas diagnostic in the patients with upper gastrointestinalbleeding (13). Upper gastrointestinal endoscopy should beperformed if the results of nasogastric aspiration showsevidence of upper gastrointestinal bleeding, or is negativefor blood and bile. Particularly in the setting of hematoche-zia leading to hemodynamic compromise, it is reasonable to

perform upper endoscopy as the initial endoscopic evalua-tion unless a copious amount of nonbloody bile is recoveredfrom the nasogastric tube while the patient is actively pass-ing red blood per rectum.

Endoscopy (colonoscopy or sigmoidoscopy) is the test ofchoice for the structural evaluation of lower gastrointestinalbleeding. Arteriography should be reserved for those pa-tients with massive, ongoing bleeding when endoscopy is notfeasible, or with persistent/recurrent hematochezia whencolonoscopy has not revealed a source. There is no role forbarium enema in the evaluation of acute, severe hematoche-zia.

The results of the largest clinical series using colonos-copy in the evaluation of acute lower gastrointestinal bleed-ing are summarized in Table 2. The overall yield of colonos-copy ranged from 6980% (13, 1618). The standardmethod of evaluation in these series was to perform ano-scopy or retroflexed view of the distal rectum to exclude ananorectal bleeding source, then proceeding proximally untilthe lesion responsible for bleeding was encountered. In thelargest clinical series by Rossini et al., total colonoscopywas necessary in only 133 of 409 cases (33%); a bleedinglesion distal to the cecum was encountered in the othercases. The most common site of bleeding was the left colon,and the most commonly encountered lesions were ulceratedcarcinomas and diverticular disease (16). It must be remem-bered that visualization of a nonbleeding potential bleedingsite (e.g., nonbleeding hemorrhoids or diverticulum) doesnot exclude the presence of more proximal pathology.

Colonoscopy is generally safe in the setting of acutelower gastrointestinal bleeding, as long as the patient hasbeen sufficiently resuscitated before the procedure. Of the549 colonoscopic examinations summarized in Table 2,only one endoscopic complication (perforation of a diver-ticulum) was reported. In two of these four clinical series, acolonic purge was administered before endoscopic exami-nation; in the other two series, colonoscopy was performedwithout prior preparation. The colonic purge used in theseclinical series was polyethylene glycol solution over $2 h,until the effluent was clear. A nasogastric tube can be usedto administer this solution if the patient is unable to tolerateit by mouth. There are no data to suggest that a colonicpurge will reactivate or increase the rate of bleeding. Thereare no studies indicating the exact optimum timing of

TABLE 2Colonoscopy in the Evaluation of Lower GI Bleeding

Series No. of Patients Average Age Colonic Purge DiagnosticYield (%)Most Common

Bleeding Lesion

Rossini (16) 409 NR No 76 Ulcerated cancerJensen (13) 80 65 Yes 74 Vascular ectasiaCaos (17) 35 NR Yes 69 Diverticular diseaseForde (18) 25 NR No 80 Diverticular disease

NR 5 not reported.

AJG August 1998 MANAGEMENT OF ACUTE LOWER GI BLEEDING 1205

colonoscopy in the setting of acute hematochezia. In thosepatients who have bled and apparently stopped, it is reason-able to administer the prep and perform the examination onan elective or semielective basis. For those patients withcontinued hematochezia, the examination should be per-formed as soon as possible.

Endoscopic therapy includes the use of thermal coagula-tion (including heater probe, bipolar/multipolar coagulation,and laser therapy), and injection of vasoconstrictors and/orsclerosants. All of these methods appear effective in con-trolling bleeding. In the absence of comparative studies, nospecific recommendations can be offered as to which endo-scopic treatment method is preferable. Laser therapy is theleast practical, as these examinations are frequently per-formed at the patients bedside, making the Nd-YAG laserunavailable. In addition, complications of treatment of vas-cular ectasia with Nd-YAG laser may be more frequent thanwith other methods of therapy; Rutgeerts et al. reported a10% complication rate in their series (19). Endoscopic treat-ment can clearly be provided for vascular lesions, bleedingfrom polypectomy sites, and some colonic ulcers (2023).Recently techniques of coagulation of arteries within bleed-ing diverticula have been described (23).

Arteriography may also be performed in the patient withacute lower gastrointestinal hemorrhage. The results of thelargest clinical series using arteriography in the evaluationof acute lower gastrointestinal bleeding are summarized inTable 3. The overall yield of arteriography was 4078%(2428). When a source of active bleeding is identified,surgery may be performed, or arteriographic techniques toprovide hemostasis (including injection of intraarterial va-sopressin, or superselective embolization with materialssuch as gelatins or oxidized cellulose) employed. Gomes etal. compared vasopressin to embolization with gelatin-sponge particles in patients with active bleeding, and foundinitial success rates of approximately 70% in both catego-ries. Four of 16 patients treated with vasopressin rebledduring or after the infusion (29). Guy et al. report a successrate of 90% in controlling acute bleeding with use of su-perselective embolization with polyvinyl alcohol particles(30).

As noted in Table 3, the reported complication rate fordiagnostic arteriography in acute gastrointestinal bleeding isapproximately 24%. Potential complications of this tech-

nique include contrast allergy, contrast induced renal fail-ure, bleeding from arterial puncture, or embolism fromdislodged thrombus. There are additional potential compli-cations of arteriographic therapy for acute bleeding. In thepreviously mentioned series from Gomes et al., complica-tions of vasopressin occurred in eight of 23 patients (35%),and in four of 24 (17%) of patients treated with emboliza-tion. Many of these complications were minor and self-limited, but major complications included gangrene of thetoes in one patient, infarction of bowel in one patient, andformation of a duodenocolic fistula in one patient (29).Myocardial ischemia is another potential side effect of in-traarterial vasopressin infusion. Given the overall lowerdiagnostic yield of arteriography compared with colonos-copy, the need to transport the patient to the radiology suite,and the apparently larger complication rate of arteriographycompared with colonoscopy, it is reasonable to recommendcolonoscopy over arteriography as the test of choice forstructural evaluation of the patient with acute lower gastro-intestinal bleeding. Arteriography should be reserved forthose patients with massive, ongoing bleeding where endos-copy is not feasible, or with persistent/recurrent hematoche-zia where colonoscopy has not revealed a source.

There are a variety of nuclear medicine scans that can beused for the evaluation of the patient with gastrointestinalbleeding. A commonly utilized scan currently is the 99mTc-pertechnetate labeled RBC scan. Although during arteriog-raphy the rate of bleeding necessary to detect extravasationinto the bowel from the bleeding site is estimated to be 11.5ml/min, bleeding rates as low as 0.1 to 0.4 ml/min arereportedly detectable with this technique (31). In a numberof clinical series, the likelihood of a positive scan performedin the evaluation of acute lower gastrointestinal bleedingranges from 26% to 72% (3237). There is considerablediscrepancy in the literature with respect to the accuracy ofa positive scan in detecting the true anatomic site of bleed-ing. Suzman et al. found that of 37 patients undergoingsurgery for persistent lower gastrointestinal bleeding with apositive nuclear medicine scan preoperatively, 36/37 (97%)bleeding sites were accurately localized by the scan (32).However, Hunter and Pezim found a localization error of25% in patients undergoing technetium 99m-labeled red cellscans in the evaluation of lower gastrointestinal bleeding(37). Given the overall lower diagnostic yield of nuclear

TABLE 3Arteriography in the Evaluation of Lower GI Bleeding

Series Number ofPatientsAverage

AgeDiagnosticYield (%)

ComplicationRate (%)

Most CommonBleeding Lesion

Colacchio (24) 98 64 41 4 Diverticular diseaseLeitman (25) 68 63 40 NR Diverticular diseaseKoval (26) 63 58 78 2 Vascular ectasiaBrowder (27) 50 67 72 NR Diverticular diseaseBritt (28) 40 64 58 NR Diverticular disease

NR 5 not reported.

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medicine scanning compared with colonoscopy, the need totransport the patient to the radiology suite, and the possibleinaccurate localization of the site of bleeding, it is reason-able to recommend colonoscopy over nuclear medicinescanning as the test of choice for structural evaluation of thepatient with acute lower gastrointestinal bleeding. One pos-sible role for this technique is as a screening test immedi-ately before arteriography, as patients with a negative bleed-ing scan will generally have a negative arteriogram at thatpoint in time (37). However, a potential limitation to thisapproach is that in the time required to perform the nuclearmedicine scan, the patient may stop actively bleeding, elim-inating the opportunity for arteriography to have definitivelylocalized the bleeding source. No randomized trials comparethe efficacy of arteriography alone to arteriography pre-ceded by nuclear medicine scanning in the patient withactive lower gastrointestinal bleeding.

Patients with persistent or recurrent lower gastrointestinalbleeding may require surgery. Accurate presurgical local-ization of the bleeding site improves postoperative morbid-ity and mortality.

In a review by McGuire, 82 of 108 episodes (76%) ofacute lower gastrointestinal bleeding due to diverticulardisease stopped spontaneously. Virtually all patients requir-ing ,4 U of blood transfusion in a 24-h period spontane-ously stopped bleeding. However, for patients requiring .4U of blood in that time period, the likelihood of surgery was60%. In those patients in whom the bleeding site was iden-tified preoperatively, only 4% of patients subsequently ex-perienced recurrent bleeding from another colonic divertic-ulum. However, in seven patients without preoperativelocalization undergoing colectomy and ileoproctostomy,four developed anastomotic leaks, with a mortality of 29%(10). Other series have noted significant morbidity andmortality with subtotal blind colectomy for treatment ofmassive bleeding where preoperative localization of thebleeding site was unsuccessful (38, 39). Uden et al. alsofound that preoperative studies localizing the site of colonicbleeding allowed limited resection, with reduced mortality(40). Use of endoscopic and radiologic studies in an attemptto localize the site of bleeding should be performed in allcases of lower gastrointestinal bleeding, with the very rareexception of exsanguinating colonic bleeding, where imme-diate surgery (and usually subtotal colectomy) must beperformed.

In cases of lower gastrointestinal bleeding where noplausible colonic source is identified, evaluation of thesmall bowel may be necessary. Evaluation for a Meckelsdiverticulum should be performed in younger patients withacute lower gastrointestinal bleeding. Enteroscopy andsmall bowel radiography may also be performed in thepatient in whom active bleeding has ceased.

There are circumstances in which an upper gastrointesti-nal source of bleeding has been ruled out, and colonoscopy

reveals no plausible source of bleeding from the colon. Asmall bowel bleeding source should be sought. Furtherevaluation depends upon the clinical situation. In circum-stances of continued or recurrent hematochezia, arteriogra-phy (with or without antecedent nuclear medicine scanning)may localize the bleeding site. In some circumstances inwhich bleeding is ongoing and the aforementioned studiesare negative, laparotomy and intraoperative endoscopy maybe indicated.

In circumstances where hematochezia has ceased andvital signs have clearly stabilized, other structural studies ofthe small intestine may be undertaken. Endoscopic evalua-tion of the small intestine is frequently accomplished withpush enteroscopy, where a long colonoscope or dedicatedendoscope (insertion tube length 160300 cm) is advancedper os into the small intestine. Push enteroscopy confers theadvantage of biopsy of mass lesions or therapy for bleeding.In a clinical series by Foutch et al., 38% of patients withobscure bleeding had a lesion identified in the distal duo-denum or proximal jejunum on push enteroscopy. Vascularectasias were most common (41). There are no data on theuse of this technique in the evaluation of acute, hemody-namically significant lower gastrointestinal bleeding. Sondeenteroscopy involves passive migration of a small diameterendoscope through the small intestine; examination occursas the endoscope is withdrawn. A sonde enteroscope maymigrate further into the small intestine; however, this tech-nique offers a limited view of the luminal surface due to alack of tip deflection, and no therapy or biopsy can beperformed. Again, most clinical experience with this tech-nique is for the evaluation of obscure bleeding.

Meckels diverticulum should always be considered inyounger patients with lower gastrointestinal bleeding. Thereported sensitivity and specificity rates for nuclear medi-cine scanning for Meckels diverticulum are 85% and 95%respectively (4244). These lesions, as well as some otherstructural lesions of the small intestine including mass le-sions, ulcers, and Crohns disease, may be detected bybarium contrast studies of the small intestine. The literaturesuggests that small bowel enema techniques (enteroclysis)may have an increased diagnostic yield over standard smallbowel follow-through series (45, 46).

Reprint requests and correspondence: Gregory Zuccaro, Jr., M.D., De-partment of Gastroenterology Desk S-40, Cleveland Clinic Foundation,9500 Euclid Avenue, Cleveland, OH 44195.

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