[Management of the organ donor]

Brain death is associated with loss of hypothalamic, pituitary and brain stem function resulting in apnea, bradycardia and hypotension, poikilothermia, and diabetes insipidus. In order to preserve body functions mechanical ventilation is continued with the aim to maintain an arterial partial pressure of oxygen of more than 100 mmHg. Previous fluid restrictions and the application of diuretics during the treatment of high intracranial pressure frequently result in dehydration. Progressive vasodilation may induce severe hypotension and fluid replacement with cristalloids and if necessary colloids may be called for until the central venous pressure reaches 10 cm H2O. Continuous substitution of potassium and the use of hypotonic solutions such as glucose 5% may avoid hypokalaemia and hypernatraemia, respectively. Inotropic support with dopamine (5-10 micrograms/kg.min) or adrenaline (0.01-0.1 micrograms/kg.min) may be needed to maintain normal mean arterial blood pressure (65 mmHg). Polyuria (5000 ml/24 h) can be treated by continuous intravenous infusion of antidiuretic hormone (0.5-2-10 U/h). Hypothermia must be prevented by warming all fluids (37 degrees C) and covering the patient with heat saving blankets.