The combined effect of small volume hypertonic saline and normal saline solutions in uncontrolled hemorrhagic shock

Abstract

Recently, small volume hypertonic saline solution (HTS) has been suggested for treatment of trauma casualties. Previously, we reported that small volume HTS treatment of uncontrolled hemorrhagic shock (UCHS) leads to increased bleeding, hemodynamic deterioration and early mortality. In the present study, large volume normal saline solution (NS) combined with small volume HTS was used to treat UCHS in rats. The rats were randomly assorted into four groups. Group 1 (n = 9) included rats in which UCHS induced by 12 per cent resection of the tail was untreated; group 2 (n = 8) consisted of those in which UCHS was treated after 15 minutes with 41.5 milliliters per kilogram of sodium chloride, 0.9 per cent (NS); group 3 (n = 7) included rats in which UCHS was treated with 5 milliliters per kilogram sodium chloride, 7.5 per cent (HTS); and group 4 (n = 9) included rats in which UCHS was treated by a combination of HTS and NS. In group 1, resection of the tail was followed by bleeding of 4.9 +/- 0.3 milliliters in 15 minutes, a decrease in mean arterial pressure (MAP) from 105 +/- 5 to 51 +/- 3 torr (p less than 0.001) and pulse rate from 377 +/- 9 to 305 +/- 22 beats per minute (p less than 0.05). Further loss of blood after 30 minutes was 0.5 +/- 0.2 milliliters, MAP rose to 58 +/- 6 torr (p less than 0.05) with the death of two rats. Infusion of NS in group 2 was followed by further bleeding of 3.3 +/- 1.0 milliliters (p less than 0.01) and rise in MAP to 76 +/- 9 after 30 minutes. Infusion of HTS in group 3 was followed by bleeding of 1.9 +/- 0.3 milliliters (p less than 0.05) and fall in MAP to 57 +/- 14 torr (p less than 0.05). Continued loss of blood in this group resulted in further fall in MAP to 36 +/- 11 torr (p less than 0.01) with death of 71 per cent (p less than 0.01) of the rats in four hours. Combined HTS and NS infusion in group 4 was followed by bleeding of 2.0 +/- 0.4 milliliters (p less than 0.05) and an increase in MAP to 93.0 +/- 3.0 torr (p less than 0.005) after 30 minutes with the death of only one animal in four hours. Total loss of blood in the three treated groups was similar and significantly higher than in the untreated group.(ABSTRACT TRUNCATED AT 400 WORDS)