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Lower Gastrointestinal Haemorrhage
COMMON ABDOMINAL CONDITIONS
Vascular causes The splenic flexure is a watershed area between superior and inferior mesenteric arterial blood supply, and it is this area that is most at risk of ischaemia. Patients with ischaemic colitis frequently have atheromatous disease affecting other organs. Hypotension or dehydration often precipitates an episode of ischaemic colitis with the passage of dark blood and jelly-like clots per rectum,
Lower Gastrointestinal Haemorrhage Jon Lund Gill Tierney
Aetiology of lower gastrointestinal haemorrhage Neoplastic
Lower gastrointestinal (GI) haemorrhage is bleeding which originates at a point distal to the duodenojejunal flexure, but proximal to the anal canal. This condition occurs with a frequency of about 25/100,000 adult population. This is about 1/4 to 1/8 the rate of upper GI bleeding in the same population. The incidence of lower GI bleeding increases exponentially with age in parallel with development of diseases causing the bleeding, and is more common in men. Bleeding from the colon (excluding piles) accounts for the vast majority of cases.
Vascular
Benign: polyps (adenomas, hamartomas) Malignant: adenocarcinoma, squamous cell carcinoma Ischaemia: ischaemic colitis, anal fissure Malformation: angiodysplasia, haemangiomas Haemorrhoids
IBD: ulcerative colitis, Crohn’s disease Campylobacter, Clostridium difficile, Typhoid, E. coli 0157 HIV Iatrogenic Polypectomy Radiation proctitis/enteritis Drugs NSAIDs Anticoagulants Autoimmune Wegener’s granulomatosis Rheumatoid vasculitis Developmental Ectopic gastric mucosa in Meckel’s diverticulum Degenerative Diverticular disease Others Endometriosis Solitary rectal ulcer syndrome Inflammatory Infectious
Aetiology The causes of lower GI haemorrhage are given in Figure 1 and shown diagramatically in Figure 2. The most common causes are discussed below. Diverticular disease A diverticulum occurs at a site of weakness in the musculature of the colonic wall where it is pierced by vessels. This is postulated as the reason for the position of diverticular around the colon. Intramural branches of the marginal artery of the colon pass close to the diverticulum. The vessels are therefore easily ruptured into the diverticulum by trauma or ulceration, although the precise mechanism is unknown. This typically causes vigorous bleeding, often leading to hospital admission. Bleeding from colonic diverticula accounts for the majority of admissions for bleeding from the lower GI tract, although bleeding complicates only 3 to 5 % of cases of diverticulosis. Over 90% of bleeding from colonic diverticula will cease without further intervention, although a proportion of patients (about 10%) will require a blood transfusion. Bleeding may recur in 25–33% of cases, with most resolving spontaneously.
IBD, Inflammatory bowel disease
1
Causes of lower gastrointestinal bleeding Angiodysplasia
Carcinoma
Neoplasia It is uncommon for neoplasia of the lower GI tract to present with brisk bleeding, although smaller amounts of blood per rectum, or on, or mixed with, stool, are alarm symptoms of colorectal neoplasia. Bleeding may occur after endoscopic polypectomy or trans-anal procedures, and may present as primary or secondary haemorrhage. Significant bleeding after polypectomy has been reported in around 1 in 500 cases in one large series.
Meckel’s diverticulum
Solitary rectal ulcer
Jon Lund is a Consultant Surgeon at York Hospital, UK. He qualified in Nottingham and has done much of his surgical training there.
Diverticular disease
Haemorrhoids
Gill Tierney is a Specialist Registrar at Queen’s Medical Centre, Nottingham, UK. She qualified in Nottingham and has completed most of her training there. 2 SURGERY
54
© 2003 The Medicine Publishing Company Ltd
COMMON ABDOMINAL CONDITIONS
often with abdominal pain. Clinical, and more commonly subclinical, ischaemic colitis complicates aortic aneurysm repair. Characteristic ‘thumb printing’ of the mucosa may be seen on a plain abdominal radiograph due to mucosal oedema. The episode is often self-limiting and it is usually only the mucosa that is ischaemic. Sequelae of stricture or perforation occur in less than 10 to 15% of cases. Haemorrhoids may be the source of vigorous rectal bleeding, but only rarely.
• • • •
any associated change in bowel habit weight loss loss of appetite abdominal pain. Family history of either carcinoma of the colon or IBD should be established. A full examination of the patient with specific attention to the abdomen should take place in the outpatient department. Inspection of the perineum is followed by digital rectal examination, proctoscopy and rigid sigmoidoscopy, which may reveal a source of bleeding. Further evaluation of the colon by either colonoscopy or barium enema should be arranged if clinically indicated. Some clinicians would advocate colonoscopy in preference to barium enema if the bleeding is the only symptom.
Inflammatory bowel disease (IBD) Bloody diarrhoea is often a presenting feature of IBD, especially ulcerative colitis. Persistent, severe haemorrhage is an indication for operation in up to 10% of patients having a colectomy for ulcerative colitis, but such severe haemorrhage is less frequent in Crohn’s disease. IBD is discussed by Maxwell-Armstrong/Cohen on page 34.
Acute lower GI bleeding Most acute massive lower GI bleeding will settle with no treatment other than basic resuscitation. However, 10–15% of patients require urgent diagnostic and therapeutic procedures. In such emergency patients, the priority is immediate resuscitation of the subject in accordance with Advanced Trauma Life Support (ATLS) guidelines (see www.facs.org/dept/trauma/atls). Baseline blood analyses are taken, including full blood count, clotting and crossmatch of four units. History should be taken simultaneously with resuscitation if possible. A drug history should be taken with special reference to aspirin, NSAIDs and anticoagulants. An algorithm for the management of acute lower GI bleeding is given in Figure 3.
Drug causes Anticoagulant drugs may sometimes cause significant bleeding from the lower GI tract, but usually cause lesions already present to bleed more easily and severely. The most common drugs affecting the lower GI tract are NSAIDs and aspirin, both being implicated in the increased incidence of bleeding from diverticular disease and other colonic pathology. These drugs are also associated with a more non-specific colitis with bloody diarrhoea. Radiotherapy Radiation proctitis may occur after irradiation of pelvic malignancy. Infrequently, telangectasia in the rectum produced by radiotherapy may cause severe bleeding. Topical application of 4% formalin under general anaesthesia, taking care to protect the skin around the anus, has been reported to be effective treatment for this difficult condition.
Endoscopy Upper GI bleeding is more common and more immediately lifethreatening than lower GI bleeding. Moreover, it may present as rectal blood loss or fresh melaena. Hence, upper GI endoscopy should be strongly considered as the first-line investigation, especially in elderly, haemodynamically unstable patients. Colonoscopy on actively bleeding patients is often unproductive. Urgent colonoscopy (within 24 hours of cessation of bleeding) after bowel preparation will define the source of the bleeding in 48–90% of cases. Colonoscopy can be inaccurate for angiodysplasia as lesions may be easily missed, especially if bleeding quickly. Small-bowel enteroscopy either preoperatively or ‘on-table’ can be used to identify a small-bowel source if all other investigations are negative. If the above techniques have failed to show the source of bleeding and the patient continues to bleed, radiological or isotope techniques are required (see below).
Angiodysplasia Ectatic blood vessels in the mucosa and submucosa of the bowel are known as angiodysplasias. They may occur at any point in the gut and may occur in 1–2% of colons. There is no strong evidence that they are associated with other conditions. These abnormal vessels may occasionally cause lower GI haemorrhage. Reported rates vary widely, but angiodysplasia probably accounts for less than 10% of severe colonic bleeding.
Investigation and diagnosis Presentation Bleeding per rectum presenting as an emergency may be relatively minor or severe and ongoing, such that the patient becomes haemodynamically unstable. The latter fortunately accounts for less than 10% of cases. Up to 90% of lower GI bleeding will stop without further intervention.
Imaging Selective mesenteric arteriography (Figure 4): this is indicated and effective if the patient is bleeding at a rate of >1 ml/minute. This technique identifies the bleeding point in 27–77% of cases. The major disadvantage with this technique is that bleeding must be occurring during contrast injection. There is an overall complication rate of 9.3% and a major complication rate of 2.9%. Angiography more commonly demonstrates right-sided diverticular bleeding than left. It may be that bleeding is more prolonged or vigorous from these diverticula rather than from the far more common left-sided disease. Angiography is therefore requested more commonly during right-sided diverticular bleeding rather than it being a more common condition per se.
Chronic lower GI bleeding This is usually encountered in the outpatient setting where the patient is haemodynamically stable. There is time to obtain a full history from the patient with specific reference to: • the presence of blood on the paper alone or mixed with the stools • the colour of the blood
SURGERY
55
© 2003 The Medicine Publishing Company Ltd
COMMON ABDOMINAL CONDITIONS
Algorithm for the management of acute lower gastrointestinal haemorrhage Acute lower gastrointestinal bleed Haemodynamically stable – bleeding stopped
Haemodynamically unstable – bleeding continues
Consider gastroscopy Prepared colonoscopy during admission
Gastroscopy
Lesion – treat as appropriate
No lesion
Bleeding stopped
Bleeding unstable
Colonoscopy within 24 hours
Mesenteric angiogram/embolization
4 Selective mesenteric angiography.
Treatment Diagnosis and therapy may be performed simultaneously. Interventional radiology Selective mesenteric angiography permits the identification of vascular abnormalities and the precise bleeding point. In the early 1970s the therapeutic use of superselective mesenteric angiography was described. This method utilizes coils or gelfoam to embolize feeding vessels, though there is a theoretical risk of ischaemic colitis. The therapeutic use of vasopressin infusion is another method. This causes vasoconstriction and has been reported to stop bleeding in 36–100% of cases. The recurrence rate after vasopressin infusion is high. Therefore it is used to temporize an acute event or stabilize a patient prior to theatre.
Bleeding persists
Resection of identified lesion or subtotal colectomy and ileostomy 3
Endoscopy Endoscopic control of colonic bleeding utilizes thermal modalities, sclerosing agents or endoscopic clips. At endoscopy, haemostasis with either injection of adrenaline solution, or diathermy can be performed. These techniques carry a risk of colonic perforation (especially in the right colon) and so must be performed only by an experienced practitioner.
Angiodysplasia can present diagnostic difficulties. Angiography may show characteristic early venous filling, vascular tufts or ectactic veins, but often does not provide any diagnostic information. Half of angiodysplastic lesions are situated in the right colon, the rest being distributed through the remaining bowel. Barium studies: these are performed after bleeding has ceased and are much less accurate then angiography; they may miss up to 41% of bleeding lesions. The authors believe there is no role for barium studies in the acutely bleeding patient.
Surgery Laparotomy and resection of a preoperatively identified source of bleeding is appropriate when other means have failed. Blind procedures and resection of either the right or total colon for an unidentified source of bleeding have high morbidity and mortality, are associated with high rates of re-bleeding and should be avoided. In the past, a ‘blind’ right hemicolectomy was advocated, as the majority of angiodysplasia was assumed to be on the right side of the colon. The procedure of choice in patients who are bleeding from an unidentified lower gastrointestinal source is subtotal colectomy and ileostomy (see Lees/Hill, page 39). This enables a previously unidentified small bowel source to become apparent in the postoperative period. u
Isotope studies: isotope-labelled red cell scans do not replace either endoscopy or angiography, but are an adjunct to these methods. The advantage of scintigraphy is the high sensitivity in low bleeding rates (i.e. 0.1 ml/minute). Scintigraphy is well tolerated and requires no patient preparation. Technetiumlabelled red cells or technetium-labelled sulphur colloid are used. Radionuclide scanning is inaccurate in 22% of cases and often requires arteriography to confirm the diagnosis. The authors do not routinely use this technique, usually favouring mesenteric angiography.
SURGERY
56
© 2003 The Medicine Publishing Company Ltd
Vascular causes The splenic flexure is a watershed area between superior and inferior mesenteric arterial blood supply, and it is this area that is most at risk of ischaemia. Patients with ischaemic colitis frequently have atheromatous disease affecting other organs. Hypotension or dehydration often precipitates an episode of ischaemic colitis with the passage of dark blood and jelly-like clots per rectum,
Lower Gastrointestinal Haemorrhage Jon Lund Gill Tierney
Aetiology of lower gastrointestinal haemorrhage Neoplastic
Lower gastrointestinal (GI) haemorrhage is bleeding which originates at a point distal to the duodenojejunal flexure, but proximal to the anal canal. This condition occurs with a frequency of about 25/100,000 adult population. This is about 1/4 to 1/8 the rate of upper GI bleeding in the same population. The incidence of lower GI bleeding increases exponentially with age in parallel with development of diseases causing the bleeding, and is more common in men. Bleeding from the colon (excluding piles) accounts for the vast majority of cases.
Vascular
Benign: polyps (adenomas, hamartomas) Malignant: adenocarcinoma, squamous cell carcinoma Ischaemia: ischaemic colitis, anal fissure Malformation: angiodysplasia, haemangiomas Haemorrhoids
IBD: ulcerative colitis, Crohn’s disease Campylobacter, Clostridium difficile, Typhoid, E. coli 0157 HIV Iatrogenic Polypectomy Radiation proctitis/enteritis Drugs NSAIDs Anticoagulants Autoimmune Wegener’s granulomatosis Rheumatoid vasculitis Developmental Ectopic gastric mucosa in Meckel’s diverticulum Degenerative Diverticular disease Others Endometriosis Solitary rectal ulcer syndrome Inflammatory Infectious
Aetiology The causes of lower GI haemorrhage are given in Figure 1 and shown diagramatically in Figure 2. The most common causes are discussed below. Diverticular disease A diverticulum occurs at a site of weakness in the musculature of the colonic wall where it is pierced by vessels. This is postulated as the reason for the position of diverticular around the colon. Intramural branches of the marginal artery of the colon pass close to the diverticulum. The vessels are therefore easily ruptured into the diverticulum by trauma or ulceration, although the precise mechanism is unknown. This typically causes vigorous bleeding, often leading to hospital admission. Bleeding from colonic diverticula accounts for the majority of admissions for bleeding from the lower GI tract, although bleeding complicates only 3 to 5 % of cases of diverticulosis. Over 90% of bleeding from colonic diverticula will cease without further intervention, although a proportion of patients (about 10%) will require a blood transfusion. Bleeding may recur in 25–33% of cases, with most resolving spontaneously.
IBD, Inflammatory bowel disease
1
Causes of lower gastrointestinal bleeding Angiodysplasia
Carcinoma
Neoplasia It is uncommon for neoplasia of the lower GI tract to present with brisk bleeding, although smaller amounts of blood per rectum, or on, or mixed with, stool, are alarm symptoms of colorectal neoplasia. Bleeding may occur after endoscopic polypectomy or trans-anal procedures, and may present as primary or secondary haemorrhage. Significant bleeding after polypectomy has been reported in around 1 in 500 cases in one large series.
Meckel’s diverticulum
Solitary rectal ulcer
Jon Lund is a Consultant Surgeon at York Hospital, UK. He qualified in Nottingham and has done much of his surgical training there.
Diverticular disease
Haemorrhoids
Gill Tierney is a Specialist Registrar at Queen’s Medical Centre, Nottingham, UK. She qualified in Nottingham and has completed most of her training there. 2 SURGERY
54
© 2003 The Medicine Publishing Company Ltd
COMMON ABDOMINAL CONDITIONS
often with abdominal pain. Clinical, and more commonly subclinical, ischaemic colitis complicates aortic aneurysm repair. Characteristic ‘thumb printing’ of the mucosa may be seen on a plain abdominal radiograph due to mucosal oedema. The episode is often self-limiting and it is usually only the mucosa that is ischaemic. Sequelae of stricture or perforation occur in less than 10 to 15% of cases. Haemorrhoids may be the source of vigorous rectal bleeding, but only rarely.
• • • •
any associated change in bowel habit weight loss loss of appetite abdominal pain. Family history of either carcinoma of the colon or IBD should be established. A full examination of the patient with specific attention to the abdomen should take place in the outpatient department. Inspection of the perineum is followed by digital rectal examination, proctoscopy and rigid sigmoidoscopy, which may reveal a source of bleeding. Further evaluation of the colon by either colonoscopy or barium enema should be arranged if clinically indicated. Some clinicians would advocate colonoscopy in preference to barium enema if the bleeding is the only symptom.
Inflammatory bowel disease (IBD) Bloody diarrhoea is often a presenting feature of IBD, especially ulcerative colitis. Persistent, severe haemorrhage is an indication for operation in up to 10% of patients having a colectomy for ulcerative colitis, but such severe haemorrhage is less frequent in Crohn’s disease. IBD is discussed by Maxwell-Armstrong/Cohen on page 34.
Acute lower GI bleeding Most acute massive lower GI bleeding will settle with no treatment other than basic resuscitation. However, 10–15% of patients require urgent diagnostic and therapeutic procedures. In such emergency patients, the priority is immediate resuscitation of the subject in accordance with Advanced Trauma Life Support (ATLS) guidelines (see www.facs.org/dept/trauma/atls). Baseline blood analyses are taken, including full blood count, clotting and crossmatch of four units. History should be taken simultaneously with resuscitation if possible. A drug history should be taken with special reference to aspirin, NSAIDs and anticoagulants. An algorithm for the management of acute lower GI bleeding is given in Figure 3.
Drug causes Anticoagulant drugs may sometimes cause significant bleeding from the lower GI tract, but usually cause lesions already present to bleed more easily and severely. The most common drugs affecting the lower GI tract are NSAIDs and aspirin, both being implicated in the increased incidence of bleeding from diverticular disease and other colonic pathology. These drugs are also associated with a more non-specific colitis with bloody diarrhoea. Radiotherapy Radiation proctitis may occur after irradiation of pelvic malignancy. Infrequently, telangectasia in the rectum produced by radiotherapy may cause severe bleeding. Topical application of 4% formalin under general anaesthesia, taking care to protect the skin around the anus, has been reported to be effective treatment for this difficult condition.
Endoscopy Upper GI bleeding is more common and more immediately lifethreatening than lower GI bleeding. Moreover, it may present as rectal blood loss or fresh melaena. Hence, upper GI endoscopy should be strongly considered as the first-line investigation, especially in elderly, haemodynamically unstable patients. Colonoscopy on actively bleeding patients is often unproductive. Urgent colonoscopy (within 24 hours of cessation of bleeding) after bowel preparation will define the source of the bleeding in 48–90% of cases. Colonoscopy can be inaccurate for angiodysplasia as lesions may be easily missed, especially if bleeding quickly. Small-bowel enteroscopy either preoperatively or ‘on-table’ can be used to identify a small-bowel source if all other investigations are negative. If the above techniques have failed to show the source of bleeding and the patient continues to bleed, radiological or isotope techniques are required (see below).
Angiodysplasia Ectatic blood vessels in the mucosa and submucosa of the bowel are known as angiodysplasias. They may occur at any point in the gut and may occur in 1–2% of colons. There is no strong evidence that they are associated with other conditions. These abnormal vessels may occasionally cause lower GI haemorrhage. Reported rates vary widely, but angiodysplasia probably accounts for less than 10% of severe colonic bleeding.
Investigation and diagnosis Presentation Bleeding per rectum presenting as an emergency may be relatively minor or severe and ongoing, such that the patient becomes haemodynamically unstable. The latter fortunately accounts for less than 10% of cases. Up to 90% of lower GI bleeding will stop without further intervention.
Imaging Selective mesenteric arteriography (Figure 4): this is indicated and effective if the patient is bleeding at a rate of >1 ml/minute. This technique identifies the bleeding point in 27–77% of cases. The major disadvantage with this technique is that bleeding must be occurring during contrast injection. There is an overall complication rate of 9.3% and a major complication rate of 2.9%. Angiography more commonly demonstrates right-sided diverticular bleeding than left. It may be that bleeding is more prolonged or vigorous from these diverticula rather than from the far more common left-sided disease. Angiography is therefore requested more commonly during right-sided diverticular bleeding rather than it being a more common condition per se.
Chronic lower GI bleeding This is usually encountered in the outpatient setting where the patient is haemodynamically stable. There is time to obtain a full history from the patient with specific reference to: • the presence of blood on the paper alone or mixed with the stools • the colour of the blood
SURGERY
55
© 2003 The Medicine Publishing Company Ltd
COMMON ABDOMINAL CONDITIONS
Algorithm for the management of acute lower gastrointestinal haemorrhage Acute lower gastrointestinal bleed Haemodynamically stable – bleeding stopped
Haemodynamically unstable – bleeding continues
Consider gastroscopy Prepared colonoscopy during admission
Gastroscopy
Lesion – treat as appropriate
No lesion
Bleeding stopped
Bleeding unstable
Colonoscopy within 24 hours
Mesenteric angiogram/embolization
4 Selective mesenteric angiography.
Treatment Diagnosis and therapy may be performed simultaneously. Interventional radiology Selective mesenteric angiography permits the identification of vascular abnormalities and the precise bleeding point. In the early 1970s the therapeutic use of superselective mesenteric angiography was described. This method utilizes coils or gelfoam to embolize feeding vessels, though there is a theoretical risk of ischaemic colitis. The therapeutic use of vasopressin infusion is another method. This causes vasoconstriction and has been reported to stop bleeding in 36–100% of cases. The recurrence rate after vasopressin infusion is high. Therefore it is used to temporize an acute event or stabilize a patient prior to theatre.
Bleeding persists
Resection of identified lesion or subtotal colectomy and ileostomy 3
Endoscopy Endoscopic control of colonic bleeding utilizes thermal modalities, sclerosing agents or endoscopic clips. At endoscopy, haemostasis with either injection of adrenaline solution, or diathermy can be performed. These techniques carry a risk of colonic perforation (especially in the right colon) and so must be performed only by an experienced practitioner.
Angiodysplasia can present diagnostic difficulties. Angiography may show characteristic early venous filling, vascular tufts or ectactic veins, but often does not provide any diagnostic information. Half of angiodysplastic lesions are situated in the right colon, the rest being distributed through the remaining bowel. Barium studies: these are performed after bleeding has ceased and are much less accurate then angiography; they may miss up to 41% of bleeding lesions. The authors believe there is no role for barium studies in the acutely bleeding patient.
Surgery Laparotomy and resection of a preoperatively identified source of bleeding is appropriate when other means have failed. Blind procedures and resection of either the right or total colon for an unidentified source of bleeding have high morbidity and mortality, are associated with high rates of re-bleeding and should be avoided. In the past, a ‘blind’ right hemicolectomy was advocated, as the majority of angiodysplasia was assumed to be on the right side of the colon. The procedure of choice in patients who are bleeding from an unidentified lower gastrointestinal source is subtotal colectomy and ileostomy (see Lees/Hill, page 39). This enables a previously unidentified small bowel source to become apparent in the postoperative period. u
Isotope studies: isotope-labelled red cell scans do not replace either endoscopy or angiography, but are an adjunct to these methods. The advantage of scintigraphy is the high sensitivity in low bleeding rates (i.e. 0.1 ml/minute). Scintigraphy is well tolerated and requires no patient preparation. Technetiumlabelled red cells or technetium-labelled sulphur colloid are used. Radionuclide scanning is inaccurate in 22% of cases and often requires arteriography to confirm the diagnosis. The authors do not routinely use this technique, usually favouring mesenteric angiography.
SURGERY
56
© 2003 The Medicine Publishing Company Ltd