The physiological effects of hyperosmolar resuscitation: 5% vs 3% hypertonic saline

Use of 5% normal saline (NS) is gaining renewed interest. The primary aim of our study was to compare the physiological effects after the administration of different concentrations of hypertonic saline (3% vs 5%NS) in the initial resuscitation of trauma.

We performed a retrospective analysis of a prospectively collected database of all trauma patients who received hypertonic saline during initial resuscitation. Medical records were reviewed for serum electrolytes and serum osmolarity, coagulation parameters, complications, and mortality.

A total of 212 patients were included in the study, of which 170 patients received 5%NS and 42 patients received 3%NS. Both groups were similar in age (41.16 ± 19 vs 44.17 + 23.6; P = .45) and ISS score (26 [17 to 29] vs 25 [16 to 27]; P = .6). Mean serum osmolarity (316 ± 20.3 vs 294 ± 22.5; P = .02) and serum sodium levels (143 ± 8.6 vs 137 ± 10.9; P < .001) remained higher in the 5%NS group within 72 hours of admission. The pH was lower in the 5%NS group compared with the 3%NS group at 24 hours (7.29 ± .12 vs 7.33 ± .12; P = .01); however, at 48 and 72 hours (7.40 ± .07 vs 7.41 ± .07; P = .7), no difference was found. There was no difference in blood products requirement (1,734 vs 2,253 mL; P = .11) between the 2 groups.

The 5%NS has sustained higher serum osmolarity and serum sodium concentration within the first 72 hours without any increase in adverse effects in comparison with 3%NS.