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Donor Management Somchai Limsrichamrern, M.D. Department of Surgery Faculty of Medicine, Siriraj Hospital Pathophysiology of brain death Cushing’s response Autonomic storm Decreased hepatic perfusion due to intrahepatic shunt Neurogenic pulmonary edema Catecholamine decreased to below baseline in 15 minute Pathophysiology of brain death Abolished vagal tone Decreased carbon dioxide production Arterial and venous vasomotor collapse Activation of proinflammaory and immunoregulatory pathway Routine care and monitoring Arterial line CVP Temperature Hourly urine output Frequent laboratory tests Swan-Ganz catheter Goal of management Organ viability and function after transplantation correlates with donor care To increase usability of organs To optimize organ perfusion and tissue oxygen delivery Goal of management Systolic blood pressure: 100-120 mmHg Central venous pressure: 8-10 mmHg Urine output: 100-300 ml/hr Core temperature: > 35º c Arterial oxygen pressure: 80-100 mmHg Oxygen saturation: > 95% pH: 7.35-7.45 Hematocrit: 30-35% Cardiovascular support Hypertension Hypotension Hypovolemia Decreased vascular resistance Cause of hypotension Hypovolemia Hypothermia Cardiac dysfunction Arrhythmia Acidosis Hypoxemia Excessive PEEP Congestive heart failure Myocardial sequelae of autonomic storm Cause of hypotension Cardiac dysfunction Cardiac injury Preexisting cardiac disease Hypophosphatemia Hypocalcemia Drug side effect or overdose (beta blocker, calcium channel blocker) Hypovolemia Arterial and venous vasomotor collapse Dehydration (fluid restriction) Insufficient resuscitation Polyuria (Osmotic diuresis, diabetes insipidus, hypothermia) Third space loss Decreased intravascular oncotic pressure Cardiovascular support Optimize volume status Dopamine is the drug of choice Try to avoid α-adrenergic agonist Urine output not reliable Respiratory support Frequent endotrachial suctioning Use low level of PEEP Tidal volume 10-15 ml/kg Maintain PaO2 greater than 100 mmHg Avoid using high PEEP Increase FiO2 non-lung donor Renal function Maintain adequate perfusion Maintain adequate urine output Minimize use of vasopressor Polyuria (DI, osmotic diuresis) Diabetes insipidus found in 80% Central diabetes insipidus Urine output > 500 ml/hr Serum sodium > 155 mEq/L Urine specific gravity < 1.005 Serum osmolarity > 305 mOsm/L Effect of hypernatremia Hypernatremia was associated postoperative graft dysfunction Graft loss in up to 33% Correction of hypernatremia Keep final serum sodium level < 155 mEq/L Liver Transpl Surg - 1999 Sep; 5(5): 421-8 Treatment of DI Hypotonic solution (D5W, .45NaCl) Desmopressin 1-2 µg IV every 8-12 hr Vasopressin infusion 1.2 unit/hr Endocrine therapy Low T3 level: routine use not recommended Steroid: may decrease proinflammatory reaction, routine use not recommended Insulin: use to treat hyperglycemia, increase hepatic glycogen storage Prevention of hypothermia Brain dead donors are poikilothermic Maintain temperature > 35ºc Prevent heat loss Rewarm Organ preservation To preserve the viability of organ for as long as possible Hypothermia slows metabolism Cooling organs from 37 to 0 degree Celsius slows metabolism by a factor of 12-13 Ischemia causes cell swelling Organ preservation Collin’s solution University of Wisconsin solution Both are high in potassium UW solution contain impermeants which help reduce cell swelling Ideal cadaver donor Young adult with no significant medical problem Brain death due to closed head injury No extracerebral trauma Brief hospitalization Normal blood pressure and heart rate without vasopressor Excellent organ function Contraindication Unknown cause of death Extracranial malignancy HIV + Uncontrolled sepsis especially fungal Relative contraindication Extreme age Intracranial malignancy HCV + or HB core antibody + Bacteremia Procurement injury Preexisting medical problem ขั้นตอนการขอรับบริจาค พบผูป ้ ่ วยที่อาจเป็ นผูบ้ ริ จาคอวัยวะ ยืนยันภาวะสมองตาย แพทย์แจ้งข่าวสมองตายแก่ญาติ ผูป ้ ระสานงานขอบริ จาคจากญาติ แจ้งศูนย์รับบริ จาคอวัยวะสภากาชาดไทย ตรวจยืนยันภาวะสมองตายและความเหมาะสมใน การเป็ นผูบ้ ริ จาค Pitfall Care of potential donor Diagnosis of brain death Documentation of brain death Consent form Preparation for organ retrieval Operative injury Packaging Diagnosis of brain dead Drug Hypothermia Decorticate Decerebrate Spinal cord injury Documentation of brain death Thank you.
