Effects on cerebral hemodynamics of resuscitation from endotoxic shock with hypertonic saline versus lactated Ringer's solution

This study was carried out to determine whether 7.5% hypertonic saline (HSS) and lactated Ringer's solution restore cerebral hemodynamics comparably when used for resuscitation from endotoxic shock. Endotoxic shock was produced in 13 dogs by the iv administration of 1.5 mg/kg Escherichia coli endotoxin. After 90 min of shock, seven animals were resuscitated with lactated Ringer's solution, 60 ml/kg iv, and six with 7.5% HSS, 6 ml/kg iv. Both solutions increased cardiac output and mean arterial pressure. With HSS, intracranial pressure was lower immediately after resuscitation (p < .001) and one hour later (p < .01). However, cerebral blood flow was not increased by either fluid and, due to hemodilution, cerebral oxygen transport decreased during resuscitation in both groups of animals. Thus, HSS restored systemic hemodynamics and maintained a lower intracranial pressure during resuscitation from endotoxic shock, but failed, as did lactated Ringer's solution, to restore cerebral blood flow and oxygen transport.