EMS World Magazine is the most authoritative source in the world for clinical and educational material designed to improve the delivery of prehospital emergency medical care.
Issue link: https://emsworld.epubxp.com/i/576325
32 OCTOBER 2015 | EMSWORLD.com T his month's CE article looks at cirrhosis and its complications. In an attempt to best understand the signs and symptoms and progression of this disease, we will review the anatomy, physiology and pathophysiology of the liver and cirrhosis and the clinical manifestations of the disease and its com- plications. Anatomy of the Liver The liver is the largest visceral organ in the body, and the majority of its mass is located in the upper right abdominal quadrant and extends into the upper left quadrant, lying directly below the diaphragm. It weighs about 3.3 lbs. (1.5 kg) in the average adult male. The liver is encased in a tough, fibrous capsule (Glisson's capsule) and covered by a layer of visceral peritoneum. It is held in place in the abdomen by several ligaments, including the falciform, round and coronary ligaments. The gallbladder is a small, hollow, pear-shaped muscular sac that lies on the posterior surface of the liver. While not a true part of the liver, it works closely with the liver to store and secrete bile pro- duced in the liver to aid digestion. Blood Supply The liver is the largest blood reservoir in the body, receiving about 25% of the cardiac output. It is unique in that it has a double blood supply, receiving blood from both the hepatic portal vein and hepatic arteries. The hepatic portal vein delivers approximately 66% of the liver's blood supply and carries venous blood drained from the spleen, gastrointestinal tract and other organs. 1 It supplies nutrients and other essential chemicals absorbed by the digestive tract. The hepatic arteries supply oxygenated arterial blood to the liver, accounting for the remaining 33% of its blood flow. 1 Hepatic Portal Circulation The splenic vein, gastric vein, esophageal vein, and inferior and superior mesenteric veins all feed into the portal vein and together comprise the hepatic portal circulation. Some of these blood vessels surround the esophagus and stomach, and the mesenteric veins contain products absorbed from digestion in the GI tract. The liver then performs its functions on this venous blood, processing useful products of digestion and filtering out toxins. Liver Cells The liver is divided into approximately 100,000 individual lobules, the basic functional unit of the liver. Located in the lobules are the liver cells, or hepatocytes. Each hepatocyte is in contact with at least one of the sinusoid blood vessels that run between the portal and central veins. Another type of cells found in the liver are phagocytic macrophage cells called Kupffer cells. These are located in the sinusoids and engulf cell debris, pathogens and old or damaged red blood cells. Blood f lows into the liver via the hepatic arteries and portal vein, then through the liver sinusoids and empties into the cen- tral vein of each lobule. The central veins coalesce into hepatic veins, which leave the liver and drain Cirrhosis and Its Complications Catch this liver scarring problem early, because its efects can be life-threatening By Scott R. Snyder, BS, NREMT-P, Sean M. Kivlehan, MD, MPH, NREMT-P, & Kevin T. Collopy, BA, FP-C, CCEMT-P, NREMT-P, WEMT TABLE 1: MAJOR FUNCTIONS OF THE LIVER Digestive and metabolic functions Synthesis and secretion of bile; Storage and of glycogen and lipids; Regulation of blood glucose, fatty acids and amino acids; Storage of fat-soluble vitamins and minerals; Breakdown of hormones such as insulin and estrogen; Synthesis of angiotensinogen; Inactivation and absorption of toxins. Hematologic functions Synthesis of clotting factors; Removal of damaged and/or old RBCs and pathogens from circulation; Synthesis of plasma proteins. CONTINUING EDUCATION This CE activity is approved by EMS World, an organization accredited by the Continuing Education Coordinating Board for Emergency Medical Services (CECBEMS), for 1 CEU. OBJECTIVES • Discuss the epidemiology of cirrhosis. • Explain the signs and symptoms of cirrhosis. • Discuss complications of cirrhosis. • Discuss the prehospital management of the patient with cirrhosis and its complications. CONTINUING EDUCATION To take the CE test that accompanies this article and receive 1 hour of CE credit accredited by CECBEMS, go to rapidce.com . Test costs $6.95. Questions? E-mail editor@EMSWorld.com.