Post on 22-Dec-2015
description
PATHOPHYSIOLOGYDISEASES OF THE DIGESTIVE SYSTEM
Manukau Institute of Technology
BN3-S1-2012
Common Manifestations of GIT Diseases
Pain/heartburn/discomfort Difficulty in swallowing Loss of appetite Nausea Vomiting Gaseous distension Diarrhoea Constipation Bleeding
Simple Classification
ITIT
Simple Classification
Infection Viral Bacterial fungal
Traumatic Inflammatory Tumour
Benign Malignant
Diseases of the Mouth
Infection: herpes simplex, thrush
Trauma: injuries, accidental biting, burns
(hot drinks)
Inflammation: aphthus ulcer
Tumour: lip cancer, tongue cancer
Dysphagia
Difficulty in swallowing
Dys: Bad
Phagia: eating/swallowing
Anorexia
Loss of appetite a: without orexe: appetite ia: state or act
Causes Psychosocial Side effects of drugs Diseases
Treatment Treat the underlying cause
Nausea
Unpleasant sensation Preceded by loss of appetite Usually followed by vomiting Usually associated with:
Sweating Pallor Tachycardia (increased heart rate) Salivation Vasoconstriction
Vomiting (emesis)
Forceful oral expulsion (throwing out)
of stomach and portions of small
intestine contents• Protective mechanism
• Usually preceded by nausea
• Can lead to complications (alkalosis,
dehydration, etc.)
Vomiting
The vomiting centre receives impulses from:
GIT
Cerebral cortex
Vestibular apparatus : motion sickness
Other factors:
Drugs and toxins
Hypoxia
Vomiting
Treatment of Nausea and Vomiting
Supportive measures
reassurance
avoidance of triggering factors
bed rest if necessary
rehydration, IV fluids
Treat the underlying cause
Gastroesophageal Reflux
The “return” movement of stomach contents
Can cause heartburn Usually mild If persists, can cause
GastroEsophageal Reflux Disease (GERD) which can lead to severe heartburns and may interfere with some activities
Diarrhoea
The (frequent) passage of loose stoolTypes: Acute or chronic Watery or bloody Osmotic diarrhoea
– Non-absorbable substances (fibre) draw excess water into the intestinal lumen from the vascular component (lactase deficiency)
Secretory diarrhoea– Mucosa of the gut secretes excessive amounts
of water and electrolytes into interstitial lumen in response to irritation (bacteria, inflammation)
GIT Bleeding
Manifests as blood in vomit or blood in stool Haematemesis:
Blood in the stomach is an irritant and causes vomiting. May be bright red or ‘ground coffee’ coloured
Haematochezia:Red blood (fresh looking) in stool usually indicates bleeding in lower bowel, below the cecum. May often be the result of bleeding hemorrhoids.
Melaena:Dark blood usually indicates bleeding above the cecum.
Occult:Hidden blood can only be detected in a lab (stool sample)
Diseases of the Stomach
GastritisInflammation of the gastric mucosaTypes: Acute
Extreme stress Drugs:
Aspirin NSAI Corticosteroid Alcohol
Infection: H. Pylori Chronic
Peptic Ulcer
A group of ulcerative disorders of the upper GIT that are exposed to acid-pepsin secretions.
Most common peptic ulcers:
• Gastric
• Duodenal
Peptic Ulcer
Lesions that do not extend through the mucosal lining are called erosions.
Causes:• Helicobacter pylori• Aspirin and other NSAIDs• Exposure to irritants (cigarette smoke, alcohol, caffeine)• Physiological stress: major operations, extensive burns,
severe diseases.
Peptic Ulcer
Diseases of the Small and Large Intestine
Infection Trauma Inflammatory Bowel Disease (IBD)
Crohn Disease Ulcerative Colitis
Tumour Others:
Irritable Bowel Syndrome (IBS) Diverticular Disease Intestinal Obstruction Malabsorption
Irritable Bowel SyndromeClick on the black area to watch the video
http://www.youtube.com/watch?v=eInvmxGhsko
Inflammatory Bowel Diseasehttp://www.youtube.com/watch?v=TSLKKzZ04Dk
Diseases of the Liver and Hepatobiliry System
Common Manifestations
Pain/heaviness/discomfort Nausea Vomiting Diarrhoea Jaundice Oedema and ascites Bleeding tendency Hepatomegaly (liver enlargement)
Other Manifestations
Telangiectasia
Spider nevi
Palmar erythema
Caput medusae
Fetor hepaticus
Muscle wasting
Gynaecomastia
Caput Medusae
Jaundice
Yellowish discolouration of sclera and mucous membrane due to increased serum bilirubin.
Causes: Pre-hepatic:
haemolytic anaemia Hepatic:
Infection Cirrhosis Cancer
Post-hepatic Gall bladder stones
Diseases of the Liver
Viral Hepatitis A B C D E
Liver cirrhosis Portal hypertension Hepatic cancer
Liver Damage
Alcoholic Liver Disease
Chronic Excess Alcohol Consumption
Hepatocellular Carcinoma
Infection Hepatic Encephalopathy
Liver Failure G.I. Bleeds
-Liver decreases the formation andrelease of lipoproteins
-Lipid accumulates in liver-Over time fat cells become surrounded by fibrous tissue
-Liver becomes firm and nodules form-The liver eventually shrinks and nodules become
surrounded by connective tissue
-Liver necrosis begins-Mallory's Bodies lead to fibrosis around cells and veins
-Hepatocytes become infiltrated with WBCs-Liver enlarges
-Scar tissue develops
Alcoholic Steatosis
Alcoholic Hepatitis
Alcoholic Cirrhosis
DEATH due to....
Liver Failure
Portal Hypertension
High pressure in the portal vein and its branches
Causes• Prehepatic: Blockage occurs in bloodflow to
the liver– Portal vein thrombosis
• Intrahepatic: Blockage occurs in bloodflow within liver– Cirrhosis
• Post hepatic: Increased pressure in inferior vena cava– Right heart failure
Portal Hypertension
• The vessels most susceptible to high portal
pressures are:
– Esophageal
• Veins bulge and protrude into the lumen of the esophagus.
Vessels may haemorrhage causing exsanguination and death
– Haemorrhoidal
• Causes haemorrhoids which may also rupture into the rectum
Cholelithiasis
Gall Stones
(chole) = bile
(lithia) = stone
(sis) = process
Caused by the precipitation of substances
contained in bile – particularly
cholesterol and bilirubin
Cholelithiasis
Factors that contribute to the formation of gallstones include: Excessive excretion of cholesterol from the
liver into bile obesity, pregnancy, oral contraceptive use,
drugs that lower serum cholesterol The presence of gallbladder “sludge”
pregnancy, starvation and rapid weight loss Malabsorption of bile salts
intestinal bypass surgery, ileal disease Inflammation of the gall bladder
Cholelithiasis
Most people experience no symptoms except when the stones obstruct the bile flow
Small stones can pass into the common bile duct causing symptoms of indigestion and bilary colic (a severe pain in the upper right section of the abdomen)
Large stones are more likely to obstruct flow and cause jaundice
References
Brown, D. & Edwards, H. (Eds). (2008). Lewis’s medical-surgical nursing: Assessment & management of clinical problems (2nd ed). Sydney, Australia: Elsevier-Mosby.
Craft, J., Gordon, L., & Tiziani, A. (2011). Understanding pathophysiology. Sydney, Australia: Elsevier-Mosby
Johnstone, C., Farley, A., & Hendry, C. (2006). Nurse’s role in nutritional assessment and screening – Part one of a two-part series. Nursing Times 102 (49), 28-29
Johnstone, C., Farley, A., & Hendry, C. (2006). Nurse’s role in nutritional assessment and screening – Second of a two-part series. Nursing Times 102 (50), 28-29
Mark A. Marinella. (2008) Umbilical Complications of Malignancy. Journal of Gastrointestinal Cancer 39:1-4, 37-41