Current Reviews for Nurse Anesthetists

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2 Current Reviews for Nurse Anesthetists Publisher And Editor-in-Chief FRANK MOYA, MD Coral Gables, Florida Editorial Board Advisory Board JOHN AKER, CRNA, DNAP Iowa City, Iowa MONTE LICHTIGER, MD Coral Gables, Florida CHARLES BARTON, MSN, M.Ed. FRANK T. MAZIARSKI, CRNA Akron, Ohio Seattle, Washington CHUCK BIDDLE, CRNA Ph.D Richmond, Virginia MARY JEANETTE MANNINO, CRNA, JD Laguna Niguel, California CAROL G. ELLIOTT,CRNA, MPA, PhD Kansas City, Kansas CHARLES MOSS, CRNA,MS Larkspur, CO LINDA CALLAHAN,CRNA,Ph.D MARIA GARCIA-OTERO, Klamath Falls, OR CRNA, Ph.D Coral Gables, Florida NANCY GASKEY-SPEARS CRNA,Ph.D Pittsburgh, Pennsylvania JOSEPH A. JOYCE, CRNA, BS Winston-Salem, North Carolina SANDRA OUELLETTE,CRNA, Med, FAAN Winston-Salem, North Carolina LINDA J. KOVITCH, CRNA, MSN Bedford, Massachusetts EULA M. WALTERS,CRNA JD San Francisco, California LAURA WILD-MCINTOSH, CRNA, MSN Hillsboro, NJ Associate Publishers Joan McNulty Elizabeth Moya, J.D. Assistant Editor Linda G. Williams Assistant Publisher Barbara McNulty Donna Scott Circulation Assistants Carrie Scott Tiffany Lazarich Myriam Montes Sponsor Frank Moya Continuing Education Programs, LLC Subscription Office - Editorial Office Current Reviews Frank Moya, M.D S.E. First Avenue 1450 Madruga Ave Ft. Lauderdale, FL Suite 207 Coral Gables, FL Phone: (954) Fax: (800) Accreditation This program has been prior approved by the American Association of Nurse Anesthetists for 26 CE credits; Code Number 32615; Expiration Date July 31, Approved by Frank Moya Continuing Education Programs,LLC. Provider approved by the California Board of Registered Nursing, Provider Number CEP 1754, for 26 contact hours; and Florida Board of Nursing, Provider Number FBN 2210 for 26 contact hours. In Accordance with AANA directives, you must get 80% of the answers correct to receive one credit for each lesson, and if there is a failure, there is no retaking. Disclosure Policy Frank Moya Continuing Education Programs, LLC, in accordance with the Accreditation Council for the Continuing Medical Education s ( ACCME ) Standards for Commercial Support, will disclose the existence of any relevant financial relationship a faculty member, the sponsor or anyone else who may be in a position to control the content of this Activity has with any commercial interest. BEFORE STARTING, PLEASE SEE LAST PAGE TO READ WHETHER THERE ARE ANY RELEVANT RELATIONSHIPS TO DISCLOSE AND, IF SO, THE DETAILS OF THOSE RELATIONSHIPS. Current Reviews is intended to provide its subscribers with information that is relevant to anesthesia providers. However, the information published herein reflects the opinions of its authors and does not represent the views of Current Reviews in Clinical Anesthesia, Current Reviews for Nurse Anesthetists, or Frank Moya Continuing Education Program, LLC. Anesthesia practitioners must utilize their knowledge, training and experience in their clinical practice of anesthesiology. No single publication should be relied upon as the proper way to care for patients. The information presented herein does not guarantee competency or proficiency in the performance of procedures discussed. Copyright 2013 by Current Reviews Reproduction in whole or in part prohibited except by written permission. All rights reserved. Information has been obtained from sources believed to be reliable, but its accuracy and completeness, and that of the opinions based thereon, are not guaranteed. Printed in U.S.A. Current Reviews is published biweekly by Current Reviews, 1828 S.E. First Avenue, Ft. Lauderdale, FL POSTMASTER: Send address changes to Current Reviews, 1828 S.E. First Avenue, Ft. Lauderdale, FL

3 Anesthesia and Liver Disease Terrence L. Trentman, M.D. Associate Professor Anesthesiology Department of Anesthesiology Mayo Clinic in Arizona Phoenix, Arizona LESSON OBJECTIVES Upon completion of this lesson, the reader should be able to: 1. List the common causes of acute and chronic liver failure. 2. Define cirrhosis. 3. Discuss the changes associated with cirrhosis. 4. Identify anesthetic goals for the surgical patient with cirrhosis. 5. Describe the consequences of compromised hepatic synthetic function. 6. List the sequelae of portal hypertension. 7. Explain how the MELD score is calcuulated. 8. Explain how the Child-Pugh classification and the MELD score can be used to guide surgical decision making. 9. Identify the classes of anesthetic drugs best minimized or avoided in cirrhotic patients. 10. Discuss three extra-hepatic syndromes associated with cirrhosis that increase perioperative risk. Current Reviews for Nurse Anesthetists designates this lesson for 1 CE contact hour in pharmacology/therapeutics. Introduction Liver disease is common, with multiple etiologies and complex effects on almost every organ system. In the United States, alcohol dependence is seen in th some 14 million adults and is the 10 most common cause of death is chronic hepatic disease. Of the 5 million Americans infected with hepatitis B or C, 20-30% will develop cirrhosis. Because of the multiple physiologic effects of liver disease, these patients can be some of the most challenging that an anesthesia provider will face. This lesson presents a basis for understanding the pathophysiology of chronic and acute liver disease and a rationale for optimizing anesthetic management. Based upon a review of current literature, discussion points in this lesson include: # What is the normal hepatic blood supply, and what are the sequelae of portal venous hypertension? # What are the common causes of hepatic disease? # What tools are available to quantify the severity of cirrhosis? # Can we correlate the severity of cirrhosis with perioperative outcome? # How do the syndromes associated with hepatic disease increase perioperative risk? # How do anesthesia choices, including techniques, drugs and hemodynamic management, influence perioperative outcome? Curr Rev Nurs Anesth 36(1):1-12,

4 Liver Functions The liver has multiple vital physiologic functions. It synthesizes proteins and clotting factors, detoxifies drugs and products of metabolism, excretes waste products, and stores and supplies energy. Medications # Acetaminophen # Vecuronium # Cisatracurium # Atracurium # Sevoflurane # Isoflurane # Desflurane # Halothane # Octreotide = Sandostatin (brand name) # Midodrine = Amatine, ProAmatine, Gutron (brand names) Table 1 Etiologies of Chronic Liver Disease # Chronic hepatitis (viral hepatitis C or B), autoimmune, alcohol # Non-alcoholic steatohepatitis (NASH) # Hemochromatosis # Wilson s disease # Primary biliary cirrhosis # Primary sclerosing cholangitis # Alpha-1 antitrypsin deficiency # Prolonged cholestasis # Toxins/drugs # Cryptogenic, hepatic venous outflow obstruction # Cystic fibrosis Hepatic Blood Supply Understanding hepatic blood flow under normal conditions and in the cirrhotic patient is essential to understanding the sequelae of chronic liver disease. Of primary importance is the fact that the cirrhotic liver is hard and nodular. This leads to changes in hepatic blood flow that affect many organ systems. Venous blood supply. The blood supply to the liver is primarily through the portal vein, which supplies approximately 70% of liver blood flow, with the remaining 30% coming from the hepatic artery. The liver receives approximately 25% of cardiac output. When the liver is cirrhotic, blood backs up into the portal venous system causing portal hypertension. This leads to many of the serious sequelae of chronic liver disease, including stomach and esophageal varices with associated bleeding and anemia, hypersplenism with thrombocytopenia and increased risk of bleeding, endocrine abnormalities including diabetes, and ascites from leakage of fluid out of the gut due to low oncotic pressure (hypoalbuminemia). Decompressive surgery. It is noteworthy that one of the older operations performed in an attempt to decompress the portal venous system was the splenorenal shunt procedure. In this large abdominal operation, a shunt was placed between the splenic vein and the left renal vein in an effort to reduce portal hypertension. This operation was associated with significant morbidity and mortality, but it also led to early efforts to gauge perioperative risk in cirrhotic patients (see Child s classification, below). Modern techniques. A current interventional radiology technique is the TIPS (Transjugular Intrahepatic Portosystemic Shunt) procedure. In the procedure, the hepatic vein is accessed via the internal jugular vein, and a shunt is deployed between the hepatic vein and the portal vein through the liver parenchyma. The TIPS procedure is used primarily to treat bleeding varices and refractory ascites by effectively bypassing the cirrhotic liver and partially decompressing the portal venous system. Risks associated with the TIPS procedure include those typical of central venous catheter insertion, inadvertent puncture of the liver capsule causing hemoperitoneum, inadvertent formation of a shunt between the hepatic artery or bile ducts and the portal vein, and development or worsening of encephalopathy after the procedure. Portosystemic encephalopathy has an incidence of about 30% after TIPS. Biochemical Markers There are a number of biochemical markers used to evaluate hepatic function. Synthetic function is quantified by a number of studies, including prothrombin time, cholesterol and albumin levels. Cholestatic or infiltrative hepatic conditions are associated with elevated alkaline phosphatase. Cellular integrity is judged by transaminases, including aspartate aminotransferase (AST) and alanine aminotransferase (ALT). It is noteworthy that an AST two to three times the ALT suggests alcoholic liver disease. The liver s ability to detoxify is in part judged by the ammonia level. Excretory function is gauged by direct bilirubin. Direct bilirubin, which is water soluble, is the product of conjugation of bilirubin in the liver. If direct bilirubin is elevated, it suggests that the liver is unable to excrete (i.e., due to bile duct stones or cancer). 4 Current Reviews for Nurse Anesthetists

5 Indirect bilirubin results from breakdown of red blood cells in the spleen. Indirect or unconjugated bilirubin represents bilirubin being transported from the spleen to the liver. Indirect bilirubin is elevated if there is excess heme production (e.g., hemolysis) or cirrhosis where the liver is unable to conjugate the indirect bilirubin. In this scenario, direct bilirubin levels may be normal while total bilirubin is elevated. Cirrhosis is the common final pathway of all chronic liver disease, most notably hepatitis C and alcoholic liver disease in the United States. Cirrhosis Cirrhosis is characterized by chronic liver injury with fibrosis and regenerative nodules. In its late stages, cirrhosis is considered irreversible and only treatable with liver transplantation. Table 1 lists common causes of chronic liver disease while Table 2 lists its clinical sequelae. Decompensated cirrhosis is associated with major complications that relate to liver dysfunction and portal hypertension. These include encephalopathy, ascites, esophageal bleeding, and subacute bacterial peritonitis (SBP, infection of ascitic fluid). Other sequelae of cirrhosis result from inadequate metabolism of vasoactive substances from the gut, including nitric oxide, glucagon, prostacyclin, cytokines, endotoxins, and adenosine. Increased circulating levels of vasodilators result in peripheral and splanchnic vasodilatation and an effective reduction in central blood volume. This results in the classic physiology of chronic liver disease with low systemic vascular resistance (SVR)/high cardiac output (CO). Despite the increased cardiac output, hepatic blood flow is reduced in cirrhosis. Table 2 Clinical Sequela of Chronic Liver Disease # Jaundice # Ascites # Cutaneous findings # Encephalopathy # Portal hypertension # Pulmonary hypertension # Hepatorenal syndrome # Splenomegaly, thrombocytopenia # Bleeding tendencies # Endocrine abnormalities, diabetes # Hepatocellular carcinoma In addition to the low SVR/high CO state, patients with chronic liver disease have increased dysrhythmias, including atrial and ventricular escape beats and atrial fibrillation and flutter. Preoperative Assessment of the Patient with Liver Disease The patient with known or suspected liver disease should be evaluated first with a history and physical exam. Many patients with liver disease are asymptomatic, so risk factors such as alcohol use, a history of illicit drug use or blood transfusion should be identified. Symptoms of liver disease (such as fatigue or pruritis) may be non-specific, while signs on physical exam like palmar erythema, spider telangiectasias, gynecomastia or ascites are more suggestive of liver dysfunction. Patients with asymptomatic biochemical abnormalities present a unique challenge in the preoperative setting. The following are general guidelines: # ALT and AST are elevated but less than twice normal with normal alkaline phosphatase, bilirubin, and international normalized ratio (INR): proceed with surgery. # ALT and AST are more than twice normal and they remain elevated after repeated testing: formal assessment is indicated (ultrasonography, computed tomography, or liver biopsy) prior to elective surgery. # If the transaminases and INR are abnormal, suspect hepatobiliary dysfunction: formal assessment is indicated prior to elective surgery. # If the alkaline phosphatase is elevated with elevated transaminases, suspect biliary disease: formal assessment prior to elective surgery. Predicting Patient Risk As noted, cirrhosis is common, but predicting perioperative risk in these patients can be challenging. It is well known that morbidity and mortality is high for cirrhotic patients, especially when they undergo major surgery. As an example, alcohol-related cirrhosis carries a five-year mortality of 58-85%. When hepatic encephalopathy is diagnosed, a one-year mortality as high as 64% has been reported. After surgery, there are multiple potential etiologies of mortality in these patients (Table 3). Child s Classification One of the early efforts to correlate the relationship between liver disease and perioperative outcome was Child s classification. Child s classification divided patients into Class A, B and C with Class C being the highest risk. Bilirubin, albumin, ascites, encephalopathy and nutritional status were used as criteria to classify the patients. However, the clinical findings incorporated in Child s classification system were vague and patients often did not fit well into one category. In the 1970s, Dr. Pugh modified Curr Rev Nurs Anesth 36(1):1-12,

6 Table 3 Common Causes of Death Following Major Surgery in Patients with End-stage Liver Disease # Liver failure # Sepsis # Hemorrhage # Renal failure # Cardiac causes Child s criteria and created a point system still used today: the Child-Pugh classification system. Encephalopathy, ascites, bilirubin, albumin and prothrombin time were used in a point system that divided patients into class A, B, or C; as before, patients in class C are at the highest risk for perioperative morbidity and mortality. Subsequent studies have demonstrated mortality as high as 80% or more for patients with cirrhosis undergoing major abdominal surgery, and emergency surgery conveys an even higher risk. Model for End-Stage Liver Disease (MELD) The MELD score has been used since 2002 as a tool to predict 3-month survival in patients with liver disease (Table 4). It has become the standard for classifying most patients on the liver transplant waiting list, replacing the old unified network of organ sharing (UNOS) categories 2A, 2B and 3. The MELD is a formula that has no subjective criteria such as nutritional status or encephalopathy. Rather, it uses creatinine, bilirubin and the INR to produce a unitless number. The higher the value, the greater the risk of death within the next 3 months. Use of the MELD score to prioritize patients has been shown to decrease the number of liver failure patients dying on the transplant waiting list. Subsequent studies have demonstrated that the MELD can also be used as a predictor of perioperative mortality in cirrhotic patients undergoing major surgery, including abdominal surgery, major orthopedic and cardiovascular procedures. An internet tool to predict perioperative mortality in liver failure patients, which is based upon the MELD score, is publically available at Using the Child-Pugh Classification and MELD Score as Decision Tools Patients can be divided into those with chronic liver disease, acute liver disease, and those with asymptomatic biochemical abnormalities (Figure 1). The patient with chronic liver disease and cirrhosis can be further sub-classified based upon their Child s class and MELD score. Those with a MELD score less than 10 or Class A can proceed with surgery versus those with a MELD score of or Class B, in which case surgery should only proceed if clearly indicated. Patients with Class C or a MELD score greater than 15 should avoid surgery if at all possible and may be candidates for transplantation. As noted above, patients with acute liver disease should not undergo elective procedures. Those with fulminant hepatic failure should also be considered for possible liver transplantation. Serologies, liver ultrasound, magnetic resonance imaging or computed tomography, and hepatic biopsy (the gold standard) are studies used to diagnose cirrhosis. Modifying Perioperative Risk Unfortunately, there is no cookbook approach to the perioperative management of patients with chronic liver disease. Anesthesia providers should be aware of the risk factors and should seek to minimize them before proceeding with elective surgery. Examples include treating ascites, elevating albumin levels, use of antibiotics for infections including SBP, analyzing coagulation and electrolyte profiles, and optimizing renal and cardiac function. Encephalopathy can be treated with lactulose and oral antibiotics. Table 4 The MELD Formula MELD Score = x Log e(creatinine mg/dl) x Log (bilirubin mg/dl) x Log (INR) e e Multiply the score by 10 and round to the nearest whole number 6 Current Reviews for Nurse Anesthetists

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8 Table 5 Causes of Acute Liver Failure # Viral hepatitis # Drugs including acetaminophen # Vascular # Acute Budd-Chiari syndrome # Ischemia # Metabolic # Reye syndrome # Acute Wilson s Disease cryoprecipitate and platelets should be based upon the patient s baseline coagulation status plus the location and magnitude of the planned surgery. Acute Liver Disease Acute liver failure is characterized by compromised liver synthetic function and encephalopathy (in the context of severe liver injury). Hepatitis viruses, toxins (e.g., drugs such as acetaminophen), vascular events (e.g., hepatic vein thrombosis = Budd-Chiari syndrome) and metabolic derangements (e.g., acute Wilson s disease) account for most of the etiologies of acute liver failure. Acute viral hepatitis causes about 2000 deaths per year in the United States (Table 5). Elective surgery is contraindicated in acute liver disease. Studies and long experience have shown that the morbidity and mortality in this patient population are prohibitively high. Contraindications to Elective Surgery in Patients with Liver Disease To summarize the concepts noted above, patients with acute viral or alcoholic hepatitis, Child s Class C cirrhosis or a MELD score greater than 15, fulminant hepatic failure, severe coagulopathy, or severe extra-hepatic complications such as cardiomyopathy, hypoxemia or acute renal failure should not undergo elective surgery. Extra-Hepatic Syndromes Associated with Chronic Liver Disease The physiologic consequences of cirrhosis can present outside of the portal venous system. The following syndromes are variably seen with chronic liver disease but add considerable perioperative risk to the patient. Hepatopulmonary Syndrome (HPS) In the presence of the hyperdynamic state of liver failure, loss of pulmonary vascular tone may occur with associated capillary dilatation and arteriovenous communications. Up to a third of end-stage liver failure patients will manifest HPS, with shunting and hypoxemia. Patients may demonstrate orthodeoxia, which is desaturation when moving from the supine to the standing position. Also seen is platypnea, shortness of breath when the patient is in the upright position. Fortunately, these patients typically respond to supplemental oxygen and in many, liver transplantation will normalize oxygenation. Portopulmonary Hypertension Pulmonary hypertension associated with cirrhosis (portopulmonary hypertension) is present in up to 20% patients with end-stage liver disease and represents a major risk factor for perioperative mortality. It may not be reversed even with liver transplantation. Indeed, severe pulmonary hypertension is a contraindication to liver transplantation. Severe pulmonary hypertension is defined as a mean pulmonary artery pressure (PAP) greater than 50 mmhg or a mean PAP greater than 35 mmhg with a cardiac output of less than 6 liters per minute. In terms of long-term outcome, retrospective data suggest that general anesthesia does not increase mortality in cirrhotic patients compared to patients receiving monitored anesthesia care or regional anesthesia. Hepatorenal Syndrome (HRS) Hepatorenal syndrome is characterized by a reduced glomerular filtration rate (GFR) and renal vasoconstriction. Table 6 summarizes the criteria, which include GFR, creatinine, creatinine clearance, and proteinuria. Table 6 Hepatorenal Syndrome (HRS) # Low glomerular filtration rate # Creatinine greater than 1.5 mg/dl or creatinine clearance less than 40 ml/min # Absence of shock, bacterial infection, fluid loss, or nephrotoxic drugs # No improvement after cessation of diuretics and a fluid load # Proteinuria less than 500 mg/day # No obstructive uropathy or parenchymal renal disease 8 Current Reviews for Nurse Anesthetists

9 Patients who have marked renal vasoconstriction may suffer renal failure. Ten percent of patients who are hospitalized with ascites develop HRS, which is classified into Type 1 and Type 2. Type 1 has a rapid and progressive course with a creatinine clearance reduction of 50% or more in 2 weeks. Type 2 HRS is a reduction of GFR that is moderate and stable. Treatment of HRS includes plasma expansion, possible TIPS procedure, the use of octreotide and the alpha-agonist midodrine, and liver transplantation. Summary Hepatic disease is common and often undiagnosed. End-stage liver disease negatively impacts almost all organ systems. Understanding the pathophysiology of cirrhosis is the basis of risk assessment. Tools such as the MELD score and the Child-Pugh classification can quantify perioperative risk and guide decision making. Preoperatively minimizing risk factors and intraoperatively avoiding harmful drugs and hemodynamic perturbations will contribute to the best possible outcome for these challenging patients. Terrence L. Trentman, M.D., Associate Professor Anesthesiology, Department of Anesthesiology, Mayo Clinic in Arizona, Phoenix, AZ trentman.terrence@mayo.edu Bibliography Cheung RC, McAuley RJ, Pollard JB: High mortality rate in patients with advanced liver disease independent of exposure to general anesthesia. J Clin Anesth 17:172-6, (Retrospective; suggests general anesthesia does not put cirrhotic patients at greater risk) Gin es P, Arroyo V: Hepatorenal syndrome. J Am Soc Nephrol 10: , (Excellent review) Jepsen P et al.: Clinical course of alcoholic liver cirrhosis: a Danish population-based cohort study. Hepatology. 51: , (64% 1-year mortality in alcoholic cirrhotic patients diagnosed with encephalopathy) Kamath P et al.: A model to predict survival in patients with end-stage liver disease. Hepatology 33:464-70, (Seminal paper on the MELD score) Keegan MT, Plevak DJ: Preoperative assessment of the patient with liver disease. Am J Gastroenterol 100: , (Good review of preoperative evaluation) Mansour A et al.: Abdominal operations in patients with cirrhosis: still a major surgical challenge. Surgery 122:730-5, (Reviews outcomes of patients with cirrhosis after abdominal operations) Ostapowicz G, et al.: Results of a prospective study of acute liver failure at 17 tertiary care centers in the United States. Ann Intern Med 137:947-54, (Describes the features, causes, and outcomes of acute liver failure) Rothenberg DM, O Connor CJ, Tuman KJ: Anesthesia and the hepatobiliary system. In Miller s Anesthesia, R Miller (ed.), Churchill Livingstone, Philadelphia, (Comprehensive summary) Teh SH et al.: Risk factors for mortality after surgery in patients with cirrhosis. Gastroenterology 132:1261-9, (Basis for use of MELD to predict postoperative risk) Ziser A et al.: Morbidity and mortality in cirrhotic patients undergoing anesthesia and surgery. Anesthesiology 90:42-53, (Enumerates risk factors for postoperative complications) Terrence L. Trentman, M.D. Dr. Trentman graduated from Tulane University School of Medicine and completed an internship, anesthesiology residency and pain fellowship at Mayo Clinic, Rochester, MN. He now practices at the Mayo Clinic in Arizona and is a member of the liver transplant team. Dr. Trentman divides his time between the general operating room, including ultrasound-guided regional anesthesia, and the chronic pain clinic. Curr Rev Nurs Anesth 36(1):1-12,

10 Tips for your Clinical Practice: Key Points # The TIPS procedure, used primarily to control bleeding esophageal varices and ascites, has a 30% incidence of encephalopathy. # Liver disease may be asymptomatic or the symptoms may be non-specific. However, the clinical signs such as palmar erythema, spider telangiectasia, gynecomastia and ascites are strongly suggestive of liver dysfunction. # The mortality of cirrhotic patients undergoing major abdominal surgery is up to 80% or greater. # Patients with acute liver disease should not undergo elective surgical procedures, while those with fulminant hepatic failure should be considered for liver transplantation. # Anesthetists should keep in mind that any factor(s) that decrease hepatic blood flow may exacerbate liver dysfunction, regardless of the anesthetic technique used. # Drugs that are eliminated by hepatic metabolism or renal excretion should be avoided when possible; propofol and succinylcholine are acceptable for rapid sequence induction. # Severe pulmonary hypertension (mean PAP > 50 mmhg or > 35 mmhg with cardiac output < 6 L) is a contraindication to liver transplantation. Robert R. Kirby, M.D. Professor Emeritus of Anesthesiology University of Florida, College of Medicine FRANK MOYA CONTINUING EDUCATION PROGRAMS, INC. & FACULTY DISCLOSURE THIS AUTHOR S AND FMCEP S SPECIFIC DISCLOSURES: The author / faculty has indicated that there is no relevant financial interest or relationship with any commercial interest. The author / faculty has indicated that, as appropriate, he/she has disclosed that a product is not labeled for the use under discussion, or is still under investigation. As a matter of policy, FMCEP does not have any relevant financial interest or relationship with any commercial interest. In addition, all members of the staff, Governing Board, Editorial Board and CME Committee who may have a role in planning this activity have indicated that there is no relevant financial interest or relationship with any commercial interest. Current Reviews is intended to provide its subscribers with information that is relevant to anesthesia providers. However, the information published herein reflects the opinions of its authors. Anesthesia practitioners must utilize their knowledge, training and experience in their clinical practice of anesthesiology. No single publication should be relied upon as the proper way to care for patients. DESIGNATON OF SPECIFIC CONTENT AREAS: Current Reviews for Nurse Anesthetists (CRNA) is designed to meet the standards and criteria of the American Association of Nurse Anesthetists (AANA) for the prior-approved continuing medical education activity, Provider-Directed Independent Study, also known as home study. CRNA is an approved program provider. CRNA has designated the lessons which meet specific content areas such as pharmacology, HIV/AIDS, etc. However, only the Board of Nursing of an individual State is the final authority in the determination of whether or not these lessons meet the State s licensure requirements. 10 Current Reviews for Nurse Anesthetists

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12 MARK ONLY THE ONE BEST ANSWER PER QUESTION ON YOUR ANSWER CARD. MARK THIS PAGE AND KEEP FOR YOUR RECORDS. 1 In accordance with AANA directives, you must get 80% of the answers correct to receive one credit for each lesson, and if there is a failure, there is no retaking. POST-STUDY QUESTIONS 1. The primary blood supply to the liver is: G A. The hepatic artery. G B. The hepatic vein. G C. The portal vein. G D. The celiac artery. 2. The BEST marker of hepatic synthetic function is: G A. Indirect bilirubin. G B. Cholesterol. G C. Ammonia. G D. Direct bilirubin. 3. Elevated direct bilirubin suggests: G A. Compromised excretory function. G B. Hemolysis. G C. Hepatic synthetic failure. G D. Portal hypertension. 4. Cirrhosis is characteriezed by: G A. Hepatitis C infection. G B. Portal hypertension. G C. Liver injury with fibrosis and regenerative nodules. G D. Alcohol overuse. 5. The MELD formula includes all of the following EXCEPT: G A. Creatinine. G B. Alkaline phosphatase. G C. Bilirubin. G D. INR. 6. The LEAST desirable volatile anesthetic agent in liver failure is: G A. Halothane. G B. G C. G D. Isoflurane. Desflurane. Sevoflurane. 7. Hepatopulmonary syndrome (HPS) is associated with platypnea, which is defined as: G A. Desaturation when moving from the supine to sitting position. G B. Pulmonary emboli from the hepatic veins. G C. Rapid desaturation upon induction of anesthesia. G D. Shortness of breath when upright. 8. Hepatorenal syndrome (HRS) criteria include: G A. Low creatinine. G B. Proteinuria > 500 mg/day. G C. Increased GFR. G D. Low creatinine clearance. 9. For hepatic failure patients, the BEST muscle relaxant is: G A. Cisatracurium. G B. Vecuronium. G C. Rocuronium. G D. Pancuronium. 10. In terms of anesthetic technique: G A. General anesthesia is acceptable only if volatile agents are avoided. G B. General anesthesia should only be used as a last resort. G C. MAC or regional anesthesia are uniformly better than general anesthesia. G D. General anesthesia does not increase mortality compared to MAC or regional anesthesia. Moving? Please notify us at least six weeks before you move to your new address, so you won t miss any issues of your subscription. The post office will not forward your subscription to Current Reviews for Nurse Anesthetists. Phone: (954) Fax: (954) or (800)