Treatment of uncontrolled hemorrhagic shock by hypertonic saline and external counterpressure

The effect of an external counterpressure device (ECPD) on hypertonic saline treatment of uncontrolled hemorrhagic shock (UCHS) was studied in rats. The rats were divided into five groups. In group 1 (n = 11) UCHS induced by incision of three radicals of the ileocolic artery was treated by 5 mL/kg NaCl 0.9% (normal saline). In group 2 (n = 20), UCHS was treated by 5 mL/kg NaCl 7.5% (hypertonic saline). In group 3 (n = 6), UCHS was treated by inflation of ECPD to 50 torr. In group 4 (n = 7), UCHS was treated by ECPD and normal saline; in group 5 (n = 9), UCHS was treated by ECPD and hypertonic saline. Incision of the ileocolic artery in group 1 rats led to a fall in mean arterial pressure to 33 torr ( P < .001) followed by a spontaneous rise to 48 torr ( P < .01) with a mortality rate of 27% and a mean survival time of 161 ± 9 minutes. Infusion of hypertonic saline during UCHS was followed by a further fall in mean arterial pressure to 18.5 torr ( P < .001); mortality was 80% within 80 minutes with a mean survival time of 35.5 minutes, which was significantly lower than in group 1 ( P < .01). Inflation of ECPD during UCHS in group 3 or treatment with ECPD and normal saline in group 4 did not alter the hemodynamic response and mortality, which were similar to those of group 1. Combined treatment of UCHS by ECPD and hypertonic saline in group 5 was followed by a rise in mean arterial pressure to 73 torr ( P < .001) and maintenance of mean arterial pressure at more than 60 torr for the three hours of observation with no mortality. We conclude that treatment of UCHS with hypertonic saline led to increased intra-abdominal bleeding, fall in mean arterial pressure, and early mortality. The application of ECPD before hypertonic saline treatment converted UCHS into “controlled” hemorrhagic shock, which responded to hypertonic saline treatment with a rise in mean arterial pressure and improved survival.