Overinflation of pneumatic antishock garments in the elderly.

The hemodynamic effects of pneumatic antishock garment application in high-risk elderly patients were examined in 10 preoperative patients (mean age 66.5 +/- 6.4 years) with the pneumatic antishock garments uninflated, after 15 minutes of inflation to 50 mm Hg, and after 15 minutes of inflation to 75 mm Hg. After inflation, significant increases in right atrial pressure (89 percent), pulmonary capillary wedge pressure (34 percent), and mean pulmonary artery pressure (21 percent) were noted. Mean peripheral arterial pressure increased 11.2 percent. Depression of the cardiac index (18 percent), left ventricular stroke work (20 percent), and right ventricular stroke work (16.4 percent) with associated increases in total peripheral resistance (26 percent) and pulmonary vascular resistance (18 percent) occurred in 5 of 10 patients. Left ventricular function curves revealed a progressive decrease in ventricular function at 50 mm Hg and 75 mm Hg. We have concluded that the effect of the pneumatic antishock garment on myocardial function is variable and unpredictably dangerous in the elderly patient with diminished myocardial reserve. As no significant benefit was derived from inflation pressures greater than 50 mm Hg in these patients, the lowest combination of pressures producing the most efficacious results should be used.