Digestive system(gastrointestinal tract/alimentary canal)Digestive system(gastrointestinal tract/alimentary canal)

It consist of mouth, oral cavity,pharynx, esophagus, stomach , small & large intestine. Salivary glands, liver, gallbladder and pancreas which secrete digestive enzymes

Function:

Ingestion, peristalsis, digestion, absorption, elimination/defecation.

Hunger: craving for food

Starvation: decrease in food intake

Appetite: desire for specific food

Hypothalamus : control centre located in brain

Oral Cavity: cheeks, lips, hard palate, soft palate, rugae, tongue, tonsils, gums, teeth(32) i.e central incisor, lateral incisor, canine, first premolar, second premolar, first/second & third molar(wisdom tooth)

Surfaces of teeth: labial,buccal,occlusal, incisal

A tooth consist of Crown, root, enamel,dentin, cementum, pulp & periodontal membrane.

There are three pairs of salivary gland parotid, submandibular & sublingual gland, there function is to secrete saliva.

Pharynx or throat is a muscular tube located in the posterior part of mouth

mouth

Oral cavity

Pathological conditions of oral cavity & teeth

• Ankyloglossia/ tongue tie: not able to protude tongue out of cavity• Apthous ulcer/stomatitis/canker: inflammation of mouth with small

ulcer.types are major & minor apthaie• Gingivitis: inflammation of gums• Dental caries: tooth decay, because of acids, pulp infection, RCT• Periodonitis: acute inflammation of gums, teeth & bone• Leukoplakia:whitish coloration of mucous membrane, it is a

precancerous condition• Erythroplakia:reddish coloration• Melanoplakia: blackish coloration• Herpetic stomatitis: HSV inflammation of the mouth• Oral Thrush/Candidiasis: Fungal infection of mouth. antifungal• Mucositis: infection of mouth by bacteria, virus, fungal, radiation

Treatment consist of oral care, control of pain with analgesics, antibiotics

Anatomy of esophagus/stomach/SI/LI

(Bile)

Function of pancreas:

Pancreatic juices (amylase/lipase)

Insulin

Duodenum: recives juice from pancreas & bile

Jejunum

IlleumCecum

Appendix

Pathology of Digestive system• Achlorhydria: lack of HCL in stomach, e.g. chronic gastritis/gastric ca.• Anorexia: loss of apetite, e.g anorexia nervosa/liver disease• Ascites:abnormal collection of fluid in peritoneum due to cirrhosis,CCF• Belching: gas expelled thru mouth• Colic: acute abdominal pain because of aerophagia/lactose allergy• Constipation:unable to defecate due to dry & hard stools• Diarrhoea:loose watery stools• Dysphagia: painful/difficulty in swallowing• Flatus: gas expelled thru anus• Gastroesophageal reflux(GERD):regurgitation of stomach contents• Heartburn: substernal, midchest burning because of GERD• Haematochezia: bright red blood from rectum e.g piles, ulcerative colitis• Melena:Black dark brown stool containg blood• Nausea: discomfort preceding vomiting• Steatorrhea: fat in the feaces• Jaundice:yellow discoloration of skin & other tissues secondary to high

bilrubin.Due to cirrhosis of liver, obstruction of bile/destruction of cells

Disease of GI tract• Peptic ulcer• Achlasia;failure of lower spinchter to relax• Anal fistula: a tube like passage connected with rectum• Peritonitis• Appendicitis• Diverticulitis• Bulimia• Colitis/enteritis: infection of colon & rectum• Botulism: food poisioning due to clostridium botulinium• Dysentry:painful inflamed intestines• Esophageal varices: swollen, twisted vein at distal end• Colonic polyposis• Crohns disease:chronic inflammation of intestine• Hernia:protusion of organ or part thru the muscle normally containing it• Irritable bowel syndrome:constipation, lower abdominal pain & bloating• Volvulus:twisting of intestine upon itself• Intussusceptions: telescoping of intestine

Test for digestive system

• Stool analysis; stool culture, microscopy• Xray abdomen for gas under diaphram• Barium swallow• Barium meal• CT scan, MRI & PET abdomen• USGProcedure:GastroscopyEsophagoscopyDuodenoscopyColonoscopySigmoidscopyProctoscopyNasogastric intubation ParacentesisColostomy

Liver

• Anatomy:

Site

division• Histology

lobules made up of hepatic cells

Bile juice

Function:

Formation of bile juice

Blood proteins used for blood clotting

Removal of RBC, WBC & some bacteria

Detoxification: removal of harmful products

Removal of glucose from blood and storage as glucagon in liver cells

Storage of vitamins and activation of vitamins

Pancreas & Gall Bladder

• Histology:

exocrine:pancreatic juiceendocrine:

glucagon, insulin & stomatostatin

Pathological conditions of pancreas, liver & GB• Panreatitis: inflammation of pancreas• Cirrhosis:chronic degeneration of liver cells• Hepatitis:inflammation of liver caused by virus

Type A transmitted by food & infected water Type B by blood, body fluids like tear, saliva Type C by blood or blood productsGallstones(cholelithaisis): hard collection of bile in gallbladderLab Test:LFT: SGOT, SGPT, S. Bilrubin, Alkaline phosphataseCT scan AbdomenERCP: endoscopic retrograde cholangiopancreatiographyLiver scanAbbreviations:BM: bowel movementGI: gastrointestinal TPN: total parentral nutritionIBD: inflammatory bowel disease PUD: peptic ulcer diseaseNG Tube:nasogastric tube BE: barium enemaNBM:nil by mouth

Drugs associated with GIT• Antacids• Antisecretories/PPI (proton pump inhibitor)

omeparazole, esmeperazole, rabeprazole,pantaprozole, ranitidine, famotidine

• Antispasmodics:diclomine, mefmanic acid,trenaxmic acid, atropine, belladona

• Digestants:Pancreatic enzyme, lipase• Antiemitics: metachlorpramide,

domperidon,odansteron, granisteron• Cathartics and

laxatives:bisacodyl,phenolphalein,psyllium husk