6.
Background: Although a positive inotropic effect of hypertonic saline has been demonstrated in isolated cardiac tissue as well as in animal preparations, no information exists about a possible positive inotropic action of hypertonic saline in humans. The aim of this investigation was to determine whether a clinically relevant positive inotropic effect can be demonstrated in humans.
Methods: Twenty-six patients without cardiovascular disease were randomized to receive 4 ml/kg of either 7.2% hypertonic saline/6% hetastarch or 6% hetastarch (control) at a rate of 1 ml *symbol* kg sup -1 *symbol* min sup -1 while under general endotracheal anesthesia. Transesophageal echocardiography was used to evaluate left ventricular function. Arterial pressure, heart rate, and left ventricular end-systolic and end-diastolic diameter, area, and wall thickness were measured immediately before and after administration of either solution. Fractional area change, end-systolic wall stress, and the area under the end-systolic pressure-length relationship curve (ESPLRarea) were calculated. ESPLRarea was used to assess left ventricular contractility.
Results: Administration of hypertonic saline/hetastarch resulted in a significant decrease of mean arterial pressure and end-systolic wall stress from 77 plus/minus 14 (mean plus/minus SD) to 64 plus/minus 17 mmHg (P < 0.01) and from 52 plus/minus 14 to 32 plus/minus 11 103 dyne/cm2 (P > 0.01), respectively. End-diastolic area and fractional area change increased from 16.5 plus/minus 2.9 to 21.7 plus/minus 3.3 cm2 (P < 0.01) and from 0.53 plus/minus 0.07 to 0.70 plus/minus 0.06 (P < 0.01), respectively, whereas there was only a minor change of ESPLRarea from 38 plus/minus 13 to 44 plus/minus 13 mmHg.cm (P < 0.05). 相似文献