Upper GI surgery. Management of a 60yo for laparoscopic cholecystectomy. Outline basic management of liver transplant surgery

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1 Upper GI surgery Management of a 60yo for laparoscopic cholecystectomy Outline basic management of liver transplant surgery Anaesthesia with portal hypertension for shunt insertion Upper GI 3.D.8.1 James Mitchell (December 24, 2003)

2 Management of a 60yo for laparoscopic cholecystectomy. Laparoscopy Intraperitoneal insufflation with gas through a paraumbilical Veress needle Pressure mmhg Usually CO 2 used Surgery Elective, moderate risk Preoperative Assessment Routine, plus Respiratory compromise: lung disease, obesity, smoking Reflux risk, airway assessment, assess need for RSI Cardiac function Autonomic dysfunction e.g. diabetes Premedication H 2 antagonist, anxiolytic Intraoperative Monitoring Routine: SpO 2, ECG, NIBP, gas analysis Arterial line if very obese Large IV Induction Routine IV induction, balanced technique unless RSI indicated Maintenance Volatile, O 2, air or N 2 O. N 2 O may worsen complications of gas embolus Narcotic analgesia, local anaesthetic in port sites High PIP may be required during pneumoperitoneum High degree of vigilance for signs of gas embolism Complications Trocar insertion and insufflation Injury to bowel, bladder, large vessels Insufflation of CO 2 intravascularly Pneumoperitoneum CO 2 absorption Fall in cardiac output Difficulty in ventilation Usual surgical risks Haemorrhage, bile leak, damage to nearby structures Change to open procedure Emergence Routine, extubation in lateral position Postoperative Analgesia Local, oral agents, IM narcotic Consider epidural if opened Ward level of care Upper GI 3.D.8.2 James Mitchell (December 24, 2003)

3 Outline basic management of liver transplant surgery Surgery High risk, semi-urgent procedure Requires tertiary hospital with special expertise Issues Perioperative management of hepatic failure Coagulopathy and potential for haemorrhage Massive transfusion and fluid requirements Hypothermia, hyperkalaemia, acidosis Often paediatric patient Prolonged anaesthesia Preoperative Assessment Complications of liver failure Electrolyte, acid base, glucose, fluid homeostasis disordered Coagulopathy Encephalopathy Other complications of primary cause of liver failure Blood-borne virus, haemochromatosis (diabetes) Crigler-Najjar syndrome (avoid barbiturates) Budd-Chiari syndrome (may need anticoagulant prophylaxis) Drug toxicity Premedication Aspiration prophylaxis, no sedation with encephalopathy Transport May be coming from ICU Monitoring and access Emergency drugs drawn up Rapid infusor, cell saver, blood warmer, humidifier, patient warmer prepared Large bore IV access x 2, PA catheter, arterial line Thromboelastograph Induction Increased risk of aspiration with ascites, risk of haematemesis, delayed gastric emptying may require RSI or FOB Positioning Care for pressure areas, prolonged laparotomy Maintenance Relaxant GA, balanced technique Air:oxygen:isoflurane does not compromise splanchnic blood flow N 2 O avoided as it worsens bowel distension and gas emboli Increased dose requirement but prolonged action from NDB Preanhepatic phase Major risks are haemorrhage and coagulopathy Oliguria treated with adequate filling, diuretic, dopamine Anhepatic phase (hours) Portal vein, IVC, hepatic artery clamped, biliary drain Diaphragm retracted: impairs venous return, reduces lung compliance Renal venous congestion, oliguria Risk of hyperkalaemia, citrate toxicity from transfusion Calcuim, magnesium, water infused to maintain usual hyponatraemia Neohepatic phase Vascular anastomoses Immunosuppression with cyclosporin, azathioprine, prednisolone Upper GI 3.D.8.3 James Mitchell (December 24, 2003)

4 Haemorrhage, coagulopathy still risks Flushing cold hyperkalaemic fluid out of liver Treat hypothermia, hyperkalaemia, acidosis Emergence ICU transfer, intubated Risks of pneumonia, ARDS, anastomotic leaks, other infection Upper GI 3.D.8.4 James Mitchell (December 24, 2003)

5 Anaesthesia with portal hypertension for shunt insertion. Major abdominal surgery in a high-risk patient. Preoperative Assessment Complications Cardiac CO, SVR, Sv O 2, BP and HR unchanged Cardiomyopathy, arrhythmias responsiveness to α agonists renal blood flow Respiratory 2,3 DPG causing right shift of Hb-O 2 dissociation curve Vasodilators (VIP, glucagon, ferritin) cause pulmonary shunting, pulmonary vascular response to hypoxia Ascites may splint diaphragm (closing volume > FRC) colloid oncotic pressure may predispose to pulmonary oedema Haematological plasma volume, Hb (bleeding, B12 deficiency), albumen Factor deficiencies: VII, V, X, fibrinogen DIC may complicate surgery Endocrine Impaired glucose tolerance ( glucagon, GH, insulin resistance) Feminization of male patients Other Encephalopathy Renal failure (hepatorenal syndrome, ATN) Altered pharmacodynamics Varices, haemorrhage Decide whether further optimization is possible Treatment of complications Vitamin K or FFP, platelets if required Specific therapy Vasopressin: preportal vasoconstriction Also coronary, arteriolar vasoconstriction Somatostatin: glucagon, gut activity, mesenteric blood flow Propranolol: CO, splanchnic vasoconstriction, renin Rebound bleeds with discontinuation Investigation FBE, U&E, LFT, clotting, XM, ABG ECG, CXR if in failure Premedication Minimal if at risk of encephalopathy sensitivity to benzodiazepines Antacid or H 2 -blocker for reflux risk Intraoperative Monitoring and access Large bore IV access (consider multiple) Routine monitoring, plus CVC, arterial line, IDC, temperature Blood and fluid warmer available ABG, Hb and glucose measurement available Anaesthetic technique High mortality in patient in hepatic failure Upper GI 3.D.8.5 James Mitchell (December 24, 2003)

6 Surgery is the major determinant of hepatic damage, not anaesthesia General anaesthesia Rapid sequence induction if recent bleeding or full stomach suspected Avoidance of hepatotoxic drugs (e.g. halothane) Some evidence of enzymes with ketamine, thiopentone and N 2 O protein binding, so dose of bound drugs such as thiopentone Aim to maintain hepatic O 2 delivery: BP, Hb, PaO 2 Epidural analgesia Contraindicated in coagulopathy or thrombocytopenia Stress response reduces hepatic blood flow Allows minimization of other anaesthetic drugs Formation of shunt: flow from portal vein to IVC IVC flow hepatic blood flow causes release of glucagon, VIP (vasodilators) portal resistance, SVR reflex SV, CO Postoperative HDU or ICU care may be needed Epidural analgesia or judicious opioids Careful fluid management Upper GI 3.D.8.6 James Mitchell (December 24, 2003)