Hepatobiliary System Overview PDF

HepatoBiliary – Pancreatic System: An Overview  HEPATIC SYSTEM Liver Approximately 3 lbs (1.37 kg) in an adult The largest organ in the body. Located directly beneath the diaphragm at right epigastric region Has two lobes divided by falciform ligament, right lobe larger t...

HepatoBiliary – Pancreatic System: An Overview  HEPATIC SYSTEM Liver Approximately 3 lbs (1.37 kg) in an adult The largest organ in the body. Located directly beneath the diaphragm at right epigastric region Has two lobes divided by falciform ligament, right lobe larger than the left lobe Able to repair itself and regenerate damaged tissue to a certain extent  Hepatic sinusoids: contain phagocytic cells that remove foreign particles from blood Central vein: - center of each lobule - where mixed blood flows towards - forms hepatic veins  Liver Ducts Hepatic duct: transport bile out of liver Common hepatic duct: formed from left and right hepatic duct Cystic duct: - joins common hepatic duct - from gallbladder Common bile duct: formed from common hepatic duct and cystic duct  Major Functions of the Liver: 1. Metabolic functions A. Carbohydrate metabolism: Gluconeogenesis = the process of the liver to convert amino acids and fatty acids to glucose Glycogenesis (glycogen synthesis) = conversion of glucose to glycogen Glycogenolysis (glycogen hydrolysis) = process of breaking down glycogen into glucose B. Protein metabolism Conversion of NH3 (ammonia) to urea C. Fat metabolism Synthesis of fatty acids from amino acids and glucose Breakdown of triglycerides D. Detoxification Inactivation of drugs and harmful substances 9  E. Steroid metabolism Excretion of gonadal and adrenal corticosteroid 2. Bile synthesis ○ Bile production by hepatocytes ○ Bile excretion = bile excreted by liver about 1 L/day 3. Storage ○ Glucose in the form of glycogen ○ Vitamin A, D, E, K 4. Phagocytic system ○ Breakdown of RBC, WBC, and bacteria ○ Breakdown of hemoglobin to bilirubin  Bilirubin Metabolism Bilirubin = is a waste product of the breakdown of the hemoglobin molecule. Aged RBC Hemoglobin Heme Globin Bilirubin (insoluble) Amino acids Attached to albumin New proteins Unconjugated bilirubin (indirect bilirubin) - insoluble Liver Unconjugated bilirubin combines with glucuronic acid (glucuronide) Conjugated bilirubin (direct bilirubin) – soluble Excreted in the bile Intestine (bilirubin reduced to urobilinogen and stercobilinogen by intestinal bacteria) Stercobilinogen gives brown color to stool Urobilinogen goes in systemic circulation and excreted in urine  Bilirubin Disorders Jaundice = yellow pigmentation of the skin and sclera Icterus = yellow coloration in the sclera of the eye Kernicterus = excessive accumulation of bilirubin in the brain that causes brain damage  Bilirubin Disorders CRIGLER-NAJJAR DISEASE → recessive inherited disorder characterized by the inability to conjugate bilirubin → patients display severe neurological impairments and have a life expectancy of one year or less  Biliary Tract Composed of gallbladder, common bile duct, cystic duct, and hepatic duct which is designed to drain bile. Gallbladder = is a pear-shaped sac located below the liver Function: To concentrate and store bile. It can hold approximately 40 – 70 ml of bile.  Pancreas A long, thin glandular organ that is essential for digestion and metabolism Two major types of cells: ○ Exocrine cells Acini cells = produce pancreatic enzymes ○ Endocrine cells - Islets of Langerhans Alpha cells = produce glucagon Beta cells = produce insulin Delta cells = produce somatostatin  Diagnostic Tests Liver Function Tests (LFT) ○ Albumin ○ Total and direct bilirubin ○ Alkaline phosphatase ○ Aspartate Transaminase (AST) / Serum Glutamic-Oxaloacetic Transaminase (SGOT) ○ Alanine Aminotransferase (ALT) / Serum Glutamic Pyruvic Transaminase (SGPT) ○ Liver biopsy = is used to procure a small sample of liver tissue to diagnose liver pathology; an invasive sterile procedure performed under local anesthesia Nursing Responsibilities: ○ Explaining the procedure to the patient. ○ Placing the patient on NPO for 12 hours prior to biopsy ○ Making sure prothrombin and hemoglobin result are available Potential Complications: ○ Bleeding ○ Puncture of the kidney or intestine ○ Puncture of the lungs with subsequent pneumothorax ○ Puncture of the gallbladder ○ Peritonitis  Endoscopic Retrograde Cholangiopancreatography (ERCP) - inspects the liver, gallbladder, and pancreas visually and radiographically. ○ A fiberoptic duodenoscope is inserted orally under general anesthesia into the duodenum. ○ Radiographic dye is introduced to visualize the liver, gallbladder, pancreas, and the different ducts. Potential Complications: ○ Perforation of the stomach, duodenum and other ducts ○ Pancreatitis ○ Anaphylactic reaction to the contrast dye ○ Aspiration of gastric contents ○ Reaction to anesthesia Nursing Responsibilities: ○ Checking the signed consent form ○ Patent IV line ○ X-rays are available ○ NPO for 12 hours ○ After the test: NPO until gag reflex returns