Gastrointestinal Bleeding

Synonyms :  

Clinical features, Diagnosis, Management, Prognosis, Nutrition, Herbs,

Gastrointestinal bleeding is conveniently classified into upper (encompassing oesophagus, stomach and duodenum) and lower (small and large bowel) gastrointestinal bleeding, which have different causes but similar clinical features. 

The common causes of upper gastrointestinal bleeding are:

       Gastric and duodenal ulcer

       Acute erosions in the stomach in acute gastritis (as discussed earlier)

       Varices of the oesophagus (such as in liver cirrhosis); usually bleeding is sudden and massive (discussed later)

       Oesophageal and gastric carcinoma

       Mallory-Weiss syndrome which refers to mucosal lacerations (tears) in the distal oesophagus and proximal stomach that occur during excessive and regular vomiting, retching or hiccupping; it frequently develops in chronic alcoholics but is may be found in bulimics as well 

The usual causes of lower gastrointestinal bleeding are:

       Carcinoma of the small intestine or colon

       Diverticular disease of the colon (diverticulosis) is characterised by pouchings of the colon mucosa through the muscle layer which are especially common in the descending colon and sigmoid. As a result of stasis of faecal material diverticula may become inflamed (diverticulitis). It appears that the diverticula form as a result of increased intracolonic pressure, and dietary factors may be partly responsible (diet of low residue) since the condition is rare in developing countries (diet rich in vegetables) and more common in Western countries (processed food). Many people who develop diverticulosis are asymptomatic and experience no complications. Others may complain of mild to moderate intermittent pain frequently colicky in character or discomfort in the left lower abdomina quadrant (sigmoid in the most common site), sometimes with local tenderness. About 15% of people with diverticulosis will eventually develop acute diverticulitis, when there is more severe pain, tenderness on palpation and guarding, and this can subside spontaneously or proceed to perforation and peritonitis. Changes in bowel habit are common, with constipation alone or with intermittent episodes of diarrhoea. Mild bleeding is a very important sign, although in most cases blood is not visible in faeces on inspection.

       Angiodysplasia of the colon (dilation and tortuosity of the submucosal veins in the colon resulting from venous obstruction), which is a degenerative process occurring usually over the age of 65 and mostly affecting the right colon.

       Inflammatory bowel disease (Crohn’s disease and ulcerative colitis)

       Infectious colitis (bacterial or parasitic)

       Haemorrhoids (dilations of rectal submucosal veins that may undergo thrombosis and inflammation; haemorrhoids are idiopathic in most patients while certain precipitating factors have also been identified such as pregnancy, obesity, ascites, constipation and straining, heart failure)

Clinical features:  < BACK TO TOP >

       Upper gastrointestinal haemorrhage is recognised by haematemesis (vomiting of blood) and/or melaena (passage of altered blood in the stools, which is tarry and sticky with a characteristic odour)

       The colour of vomited blood depends on the amount of hydrochloric acid in the stomach and the duration of its contact with the blood. Thus, if vomiting occurs shortly after the onset of bleeding, the vomitus appears red, and later the appearance will be dark red, brown or black. Precipitated blood clots and acid-degraded blood in the vomitus will produce a characteristic ‘coffee grounds?appearance when vomited.

       Blood in the gastrointestinal tract causes irritation and increased motility, and in severe bleeding gastrointestinal transit may be so rapid that the blood in the rectum is bright red (not degraded to be black and sticky).

       With bleeding from the small intestine or right colon the blood may appear in form of melaena, or dark red to brown, while bleeding from the sigmoid or rectum usually presents as fresh blood (sometimes coating the formed stools). In cases of lower gastrointestinal bleeding (mainly from small intestine) blackish stool may be due to degradation of the haemoglobin in the colon by bacteria to haematin or other pigments.

       Other symptoms vary according to the severity of the bleeding; blood loss of less than 500 mL is rarely associated with systemic signs and symptoms.

       In more serious blood loos symptoms and signs of hypovolaemia (reduced total blood in the circulation) can occur such as low blood pressure (hypotension), increased heart rate (tachycardia), pale skin, sweating, weakness, fainting.

       Any gastrointestinal bleeding may present only as iron deficiency anaemia due to unnoticed chronic loss of small amounts of the blood; this is called occult bleeding, and if detected warrants further investigation (may be linked to a malignant process, especially in the middle aged and elderly).

Diagnosis:  < BACK TO TOP >

       Physical examination and blood tests are done to assess the severity of blood loss.

       In cases of upper gastrointestinal bleeding, urgent endoscopy is necessary to determine the source of the bleeding.

       The bleeding status is ascertained by passage of a nasogastric tube, which should be aspirated at half hourly intervals and the quantity and type of aspirate recorded.

       For lower gastrointestinal bleeding, rectal examination and sigmoidoscopy will detect most causes of bleeding from the ano-rectal region.

       If blood is coming from above the rectum, colonoscopy is the investigation of choice.

       Occasionally, the site of bleeding can be detected by radionuclide scanning after infusion of ^99mTc-labelled red cells (technetium is a radioactive isotope); accumulation of radioactivity in the form of an expanding patch in an area of the gastrointestinal system is detected by a gamma camera and indicates active bleeding.

       If bleeding continues, angiography of the superior and inferior mesenteric arteries can be performed to identify leakage of contrast material into the gut on X-ray, thus identifying the site of haemorrhage.

Management  < BACK TO TOP >

       If necessary, blood replacement by transfusion must be done (usually if the patient is clinically shocked, the pulse rate is consistently >100/minute, and blood pressure is <100 mm Hg and haemoglobin is <100 g/L).

       Definitive management depends on the site and cause of bleeding; sometimes bleeding will stop spontaneously without any treatment.

       Endoscopic methods are today preferred over surgery since they are much less invasive, and they include electrocoagulation, injection of sclerosant materials and laser energy applied to a bleeding lesion under endoscopic vision.

       Bleeding from oesophageal varices can be treated by balloon tamponade with special a tube placed into the oesophagus; the inflated balloon compresses the bleeding blood vessels and stops bleeding. At the same time, gastric contents can be aspirated through the tube to assess the effectiveness of haemostasis (if there is no more blood in the stomach, the bleeding has stopped).

       If these techniques can not be used, surgery is performed (e.g., excision of the bleeding gastric ulcer, suture of the duodenal ulcer, or resection of the appropriate segment of the colon).

Prognosis  < BACK TO TOP >

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Nutrition < BACK TO TOP >

Nutrition that alleviate or prevent Gastrointestinal Bleeding :-
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Herbs < BACK TO TOP >

Herbs that alleviate or prevent Gastrointestinal Bleeding :-
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