Oncotic therapy of experimental cerebral oedema

A series of experiments were undertaken to compare oncotic gradients with osmotic gradients in the treatment of experimental cerebral oedema. Oedema was produced in dogs by a left parietal cold lesion. Animals were divided into three treatment groups. Group 1, the control animals, received intravenous crystalloid solutions after the cold lesion. Group 2 animals received mannitol, 1 gm/kg IV, one and four hours after the lesion. Group 3 animals received albumin, 1 gm/kg IV, one hour after the lesion, then a continuous albumin infusion. Serum osmotic and oncotic pressures were monitored hourly. Animals were sacrificed six hours after creation of the lesions. Effect of therapy was evaluated by determining water content of the lesion hemisphere and of the opposite hemisphere. Osmotic and oncotic pressures were changed little by the mannitol and albumin dosages employed. Water content in the areas of the cold lesions was significantly greater than that in the contralateral hemisphere in all three groups. Water content in the nonlesion hemisphere of dogs receiving albumin or mannitol was 1% less than in the control, nonlesion hemisphere, an insignificant reduction of water content. Further studies of the effects of oncotic gradients for cerebral dehydration are indicated.