Anesthesia for Liver diseased and renal disease

1. Anesthesia for Liver diseased and renal disease Dr. Bundit Chintanapramote

2. Anatomy : Liver : wt 1500 gm (2% of BW) : Blood flow 150 ml/100 gm/min (1500 ml/min, 25% of cardiac output) : Portal blood flow 75% (Oxygenation 50%) : Hepatic artery blood flow 25% (Oxygenation 50%)

3. Functions of the Liver • Metabolic • Glucose metabolism • Protein metabolism • Lipid metabolism • Protein synthesis • Coagulation factors II V VII X • Albumin • Pseudo cholinesterase

4. Functions of the Liver 3. Drug metabolism • reduce albumin • increase volume of distribution • impair phase I reaction 4. Bilirubin formation and excretion • Hyperbilirubinemia (renal dysfunction replace binding site for drugs)

5. Preoperative evaluation • Respiration system • Cardiovascular system • Gastrointestinal system • Renal system • CNS system • Hematological system • Metabolic and electrolyte

6. Preoperative assessment • CVS • 70% develop hyperdynamic circulation • increase cardiac output (CI and HR) • decrease SVR • normal or low BP (BP = COXSVR) • rhythm disturbance from electrolyte imbalance

7. Preoperative assessment 1. CVS • increase heart rate • down regulation of adrenergic receptors • down regulation of baroreceptors • Alcoholic cardiomyopathy

8. Preoperative assessment 2. Respiratory system • Restrictive lung disease from ascites or pleural effusions frequently responds to fluid removal • Intrapulmonary shunts (hypatopulmonary syndrome (HPS) hypoxia occurring in the absence of ascites or intrinsic lung disease • Ventilation – perfusion (V/Q) abnormalities

9. Preoperative assessment 3. Renal system • Salt retention due to secondary hyperaldosteronism Decrease effective circulatory volume Decrease renal blood flow Increase aldosterone Na retention, K depletion, metabolic acidosis

10. Preoperative assessment • Hepatorenal syndrome : severe liver disease : diminish effective circulatory volume : neurohumonal factors : normal histology : urine Na < 10 mEg/L • Acute tubular necrosis • Prerenal azotemic

11. Hepatorenal syndrome Major criteria • Chronic or acute hepatic disease and liver failure with portal hypertension • Serum creatinine level > 1.5 mg/dl or 24 hr cretinine clearance < 40 ml/min • Absence of shock, ongoing bacterial infection, recent use of nephrotoxic drugs, excessive fluid or blood loss • No sustained improvement in renal function after volume expansion with 1.5 L isotonic saline solution • Proteinuria < 500 mg/day and no ultrasonograhic evidence of renal tract or parenchyma disease

12. Hepatorenal syndrome Minor criteria • Urine Volume < 500 ml/day • Urine Sodium < 10 mEg/L • Urine Osmolality greater than plasma osmolality • Urine red blood cell count < 50 per high power field • Serum sodium < 130 mEg/L

13. Factor that care precipitate • Use of nephrotoxic medication (eg.) nonsteroidal anti-inflammatory drugs) • Acute gastrointestinal bleeding • Excessive diuresis • Excessive large – volume paracentesis • Infection (eg, spontaneous bacterial peritonitis sepsis

14. Preoperative assessment 4. Hematologic system 1.1 anemia ; reduce synthesis – intake, macrocytic anemia ; reduce life span – MAHA – hypersplenism ; increase loss – esophageal varices

15. Preoperative assessment 1.2 coagulopathy ; platelet quantitative and qualitative platelet defects (splenic sequestration, low levees of thrombopoietin from liver, sepsis bone marrow suppression, DIC (consumption) ; Vit K deficiency ; reduce synthesis of coagulation factors (check PT, PTT), factor VII (T½ 4-8 hr) ; 10% and 20% of patients with end-stage liver disease show baseline enhanced fibrinolysis

16. Preoperative assessment 5. CNS ; hepatic encephalopathy ; ammonia level ; 90 % mortality ; GABA receptor ; cerebral edema

17. Drug handling in liver disease 1. Biotransformation ; phase I reaction – oxidation reduction from water soluble substance (halogenated inhalation, BZP, narcotics) ; phase II reaction – conjugation to glucoronide (propofol, morphine, lorazepam, oxazepam) 2. Protein binding ; reduce albumin 3. Volume of distribution (vd) ; pancuronium

18. Surgical risk assessment: Child’s classification as modified by Pugh PT = prothrombin time. INR = international normalised ratio.

19. Effects of anesthesia on the liver • Liver blood flow  Ventilation ; spontaneous, IPPV, PEEP  Hypoxia ; vasoconstrict, sympathetic stimulation  Carbon dioxide ; normocarbia  Surgery  Drugs ; Volatile anesthetics ; IV anesthetic ; regional block

20. Effects of anesthesia on the liver 2. Liver blood flow  Volatile anesthetic ; halothane hepatitis  IV anesthetic agents ; no effect

21. Anesthetic agents 1. Premedication  short acting benzodiazepine : lorazepam, midazolam  avoid sedative in severe ascites encephalopathy 2. Induction  normal dose except hepatic encephalopathy  rapid sequence induction

22. Anesthetic agents 3. NMB  Prolong effect pancuronium, vecuronium, rocuronium  Suxamethonium  Suitable for tracium, cisatracurium 4. Opioids  avoid morphine alfentanyl

23. Anesthetic agents 5. Inhalation agent  avoid N2o in severe ascites  halothane reduce liver blood flow causing halothane hepatitis  Isoflurane, sevoflurane, desflurane can be used safely

24. Anesthetic drugs in liver failure a Halothane has been rarely reported to cause hepatitis (see p143).

25. Causes of postoperative liver dysfunction or jaundice

26. Renal diseaseSign and Symptoms of TURP syndrome • Cardiopulmonary Hypertension Bradycardia Dysrhythmia Respiratory distress Cyanosis Hypotension Shock Death

27. Hematologic and renal Hyperglycinemia Hyperammonemia Hyponatremia Hypoosmolality Hemolysis / anemia Acute renal failure Death

28. Central nervous system (CNS) Nausea / vomiting Confusion / restlessness Blindness Twitches / seizures Lethargy / paralysis Dilated / non reactive pupils Coma Death

29. Sign and Symptoms of acute hyponatrcmia

30. Risk factors for perioperative ARF

31. Anesthetic drugs in chronic renal failure