Fluid and electrolyte deficit with prolonged pneumatic antishock garment application.

Abstract

When trauma victims are within 1 hour of definitive surgical care, prehospital pneumatic antishock garment (PASG) application has not improved outcome. A resuscitative role for PASG has been suggested when transport time is longer (e.g., 4 hours). We assessed the fluid and electrolyte cost of treating posthemorrhagic hypotension with the PASG in 16 anesthetized Yorkshire piglets (30 to 32 kg). Hypotension [30 mm Hg drop in carotid arterial blood pressure (CBP)] was produced by arterial line bleeding. Hemodynamics, serum electrolytes, lactate, and tissue edema (limb circumference) were monitored. In eight animals (group 1), PASG was inflated to maintain prebleed CBP for 4 hours. In group 2, the hypotension was untreated for 4 hours. After 4 hours, shed blood (over a period of 15 minutes) and normal saline (1.5 mL/kg/minute) were infused until CBP returned to normal baseline values. Shed blood alone did not restore baseline CBP. Serum K+ increased from a baseline of 3.9 to 9.1 mmol/L in group 1, with no significant change in group 2. Serum lactate rose from 1.8 to 24.1 and from 1.7 to 6.8 mmol/L in groups 1 and 2, respectively. After 4 1/2 hours, an increase in thigh circumference (6.4 +/- 1.4 vs. 1.9 +/- 1.0 mm) and intravenous fluid required after returning shed blood (626 +/- 36 vs. 324 +/- 22 mL) was greater in group 1 (means +/- SD, p < 0.05). Other serum electrolyte values were similar for the two groups. We conclude that fluid deficit, lactic acidosis, tissue edema, and hyperkalemia are all greater with prolonged PASG application when compared with the untreated hypotensive state. These findings must be considered when suggesting more prolonged PASG application.