The effects of inflation of antishock trousers on hemodynamics in normovolemic subjects.
Antishock trousers may maintain mean arterial pressure in trauma patients by increasing central blood volume and cardiac output. Hemodynamics, end-diastolic volume, stroke volume, cardiac output, and blood pressure were recorded in eight supine, healthy men in antishock trousers using two-dimensional echocardiography. Two inflation protocols were used. The antishock trousers were inflated to 50 and 100 mm Hg in a random fashion and inflation was maintained for 30 minutes before deflation. End-diastolic volume and blood pressure rose significantly (p less than 0.05) after antishock trouser inflation of 50 and 100 mm Hg. With the 50 mm Hg inflation, the stroke volume and end-diastolic volume fell below baseline over time. This did not occur with the 100 mm Hg inflation. After suit deflation, the stroke volume, end-diastolic volume, and cardiac output increased with 50 mm Hg inflation. The study shows that the antishock trousers alter several hemodynamic parameters. With lower inflation pressures, antishock trousers cause an increase in arterial pressure by increasing peripheral resistance. At higher inflation pressures, the antishock trousers increase cardiac output and as the cardiovascular system adjusts, maintain the pressure by increasing peripheral resistance.
D000005:Abdomen; D000328:Adult; D001810:Blood Volume; D004452:Echocardiography; D006439:Hemodynamics; D006801:Humans; D007866:Leg; D008297:Male; D011312:Pressure; D011481:Protective Clothing; D012016:Reference Values; D012769:Shock / Q000503:physiopathology / Q000517:prevention & control*; D013997:Time Factors