Organ Retrieval
Terminology
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DBD: Donation after Brain Death:
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At least 2 physicians NOT involved in organ procurement must declare brain death in accordance with the American Academy of Neurology guidelines; the anesthesiologist is NOT involved in this process
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DCD: Donation after Cardiac Death:
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A DCD donor does not meet the strict criteria for brain death but has suffered a severe non-recoverable brain insult & the family has decided to withdraw life support
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Upon withdrawal of life support, the DCD donor’s death is declared based on cardiopulmonary criteria
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After death is declared, 5 minutes must pass before organ procurement begins
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Considerations for DBD
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Confirm the diagnosis of brain death & confirm wishes of patient & family:
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Declared by 2 physicians not involved with transplant
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Minimum clinical criteria for brain death met (see guidelines)
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Physiologic consequences of brain death:
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Hemodynamic instability (myocardial dysfunction, vasomotor tone, hypovolemia)
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Pulmonary dysfunction with ARDS & hypoxemia (neurogenic pulmonary edema, VAP, CHF, etc)
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Neuroendocrine dysfunction
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Diabetes insipidus (70%), hypernatremia, hypokalemia
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Hypothyroid
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Hypocortisolemia
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Hyperglycemia
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Coagulopathy/DIC (brain release of thromboplastin)
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Poikilothermia secondary to hypothalamic dysfunction
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Etiology of brain death & secondary injuries
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Trauma (potential for multi-organ involvement, pulmonary/cardiac contusions)
Goals for DBD
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Cardiac:
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Ensure adequate intravascular volume
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Use vasopressors to maintain adequate organ perfusion
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Vasopressin as 1st line agent as it treats BP & diabetes insipidus (dose = 0.01-0.04 IU/min)
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Norepinehrine & dopamine also reasonable agents
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Avoid high doses of vasopressors
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Hemodynamic goals are SBP >100 mmHg, MAP >70 mmHg, HR 60-120
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Respiratory:
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Lung protective ventilatory strategy: TV 6-8cc/kg, PEEP 8-10, avoid fluid overload, FiO2 <40% for lung retrieval
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Endocrine:
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Thyroid replacement: tetraiodothyronine 20 mcg IV bolus, then 10mcg/hr infusion
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Vasopressin 1 U IV bolues, then 0.01-0.04 U/hr infusion
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Methylprednisolone 15mg/kg IV q24h
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Keep serum glucose <8 mMol/L
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MSK: paralytics should be given during procurement to optimize surgical conditions & stop somatic response to surgical stimulus mediated by spinal cord reflexes
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Hematologic:
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Keep Hgb ~100
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Platelets & FFP if clinical bleeding, do NOT simply correct abnormal coagulation tests
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