The Clinic Pathophysiological Research On The Treatment Of Acute Cerebrovascular Lesioninduced Intracranial Hypertension With Hypertonic Saline Solution

Objective:Intracranial hypertension occurs in the acute cerebrovascular diseases and is one of their common complications. The management of intracranial pressure (ICP) determines the outcome of diseases, and reducing intracranial hypertension is important to decrease mortality in acute cerebrovascular diseases. But current strategies, which have been applied to control ICP, are unsatisfactory. Hypertonic saline solution has an osmotic effect on the cerebral interstitium. As a new hyperosmolar agent in the experimental models of traumatic brain injury and traumatic brain injuried patients, recent studies demonstrated that hypertonic saline can decrease intracranial hypertension and inhibit cerebral edema. However, hypertonic saline solution therapy requires further investigation in reducing intracranial hypertension induced by acute cerebrovascular diseases. Therefore, The aim of this study was to determine the effects of hypertonic saline solution on intracranial hypertension in patients with acute cerebrovascular diseases and its side effects on circulatory function, renal function, electrolyte and water metabolisms, and to evaluate its differences from 20% mannital when used in the same disease.MethodsThe experiment included three parts:Firstly, 20 comatose patients with cerebral hemorrhage and indications to the use of lateral ventricular puncture were treated with 23.4% hypertonic saline solution during 46 episodes of intracranial hypertention. Intracranial pressure (ICP), mean arterial pressure (MAP), central venous pressure (CVP), cerebral perfusion pressure(CPP) and plasma electrolytes were continuously monitoredbefore the treatment and during the following 6 hours.Secondly, other 15 patients with cerebral hemorrhage and indications to the use of lateral ventricular puncture were divided into 2 groups at random, and were administered intravenously with 30 mL 23.4% hypertonic saline or 250 mL 20% mannitol, respectively. Indices mentioned above plus osmotic pressure were tested repeatedly before the intervention or during the following 6 hours.Thirdly, 30 patients with acute cerebrovascular diseases were randomized as 2 groups, and were treated with 40 mL of 10% hypertonic saline solution or 250 mL of 20% mannitol twice a day for 5 days, respectively. Plasma electrolytes, osmotic pressure and renal function were tested before or in the first, third, and seventh day of administration. In addition, grading of cerebral function was conducted before and 14 days after the intervention.Results1. Effect of 23.4% hypertonic saline salution on intracranial hypertention, circulatory function and plasma electrolytes.ICP reduced from (4.1 + 1.5) kPa to (1.6+0.7) kPa in (28.8+20.7) minutes after administration of hypertonic saline solution, and came back to the former level (4.5 + 1.4 ) hours after treatment. Significant reduction of MAP and rise in CPP were found. CVP, electrolytes and osmotic pressure were relatively stable throughout the experimentation.2. The difference between 23.4% hypertonic saline salution and 20% mannitol in the effects on intracranial hypertention, circulatory function and plasma electrolytes.Hypertonic saline caused a reduction of (2.5+1.1) kPa in ICP (28+20) min after treatment with 23.4% hypertonic saline (P<0.01), and the effect lasted 3 hours. Whereas 20% mannitol produced a decrease of (2.0 ±1.3) kPa in ICP (49 + 25) min after treatment, and the effect lasted only 1 hour. No significant differences in CVP, electrolytes or osmotic pressure at 2, 4, 6 h after treatmentwere found between 2 groups.3. The difference between hypertonic saline salution and mannitol in the effects on grading of cerebral function, renal function, plasma electrolytes, and osmotic pressure.Cerebral function was remarkably improved after treatment in both groups. No statistically significant rise in plasma sodium, chloride, and osmotic pressure was detected on the first, third, and seventh day after hypertonic saline administration. Renal function kept stable in the group accepting hypertonic saline treatment, but administration of 20% mannitol caused a damage of renal function.Conclusion:Hypertonic saline solution is more effective and has a longer duration of action than 20% mannitol in the treatment of intracranial hypertension in patients with acute cerebrovascular diseases, and it can be safely used in those diseases.