How does a neuron, challenged by an increase in synaptic input, display a response that is independent of the initial level of activity? Here we show that both oxytocin and vasopressin cells in the supraoptic nucleus of normal rats respond to intravenous infusions of hypertonic saline with gradual, linear increases in discharge rate. In hyponatremic rats, oxytocin and vasopressin cells also res...

OBJECTIVE Volume replacement in septic patients improves hemodynamic stability. This effect can reduce the inflammatory response. The objective of this study was to evaluate the effect of 7.5% hypertonic saline solution versus 0.9% normal saline solution for volume replacement during an inflammatory response in endotoxemic rats. METHODS We measured cytokines (serum and gut), nitrite, and lipi...

Haemorrhagic shock, a leading cause of mortality, frequently accompanies cardiac interventions. The administration of small volumes of hypertonic saline solutions and crystalloid solutions may reduce the severity and duration of shock, and result in a decrease in adverse outcomes. Under general anaesthesia, hypotension was induced in 12 healthy dogs. After 30 min, dogs received either hypertoni...

The past decade has witnessed a resurgence of interest in the use of hypertonic saline for low-volume resuscitation after trauma. Preliminary studies suggested that benefits are limited to a subgroup of trauma patients with brain injury, but a recent study of prehospital administration of hypertonic saline to patients with traumatic brain injury failed to confirm a benefit. Animal and human stu...

BACKGROUND The infusion of small volumes of hypertonic saline solution or hypertonic saline plus dextran 70 is remarkably effective in restoring adequate hemodynamic conditions after hypovolemic shock. This prospective double-blind study compares the immediate hemodynamic effects of a bolus infusion of 7.5% NaCl or 7.5% NaCl plus 6% dextran 70 (both 2400 mOsm/L) in severe hypovolemia. METHODS...

BACKGROUND Patients with brain tumour usually suffer from increased pressure in the skull due to swelling of brain tissue. A swollen brain renders surgical removal of the brain tumour difficult. To ease surgical tumour removal, measures are taken to reduce brain swelling, often referred to as brain relaxation. Brain relaxation can be achieved with intravenous fluids such as mannitol or hyperton...

Cytotoxic brain edema—swelling of nerve and glial cells—is among the very early pathophysiologic sequelae of focal cerebral ischemia. Once cell swelling has exhausted the cerebral compliance, intracranial pressure increases and, thereby, causes secondary ischemia. Hypertonic solutions, mannitol in particular, have long been used to reduce intracranial pressure. More recently, hypertonic saline ...

To determine whether or not salt loading restricted to the brain would elevate blood pressure, chronically implanted osmotic minipumps were used to infuse hypertonic sodium chloride solutions made in artificial cerebrospinal fluid into a jugular vein intravenously or the third cerebral ventricle, intracerebroventricularly, for 11 days in awake rats. During intracerebroventricular infusion of hy...