Balanced Crystalloid Solution Versus Normal Saline on Biochemical Outcomes in Acute Medical and Surgical Patients

Abstract

Background: Concerns have been raised regarding the use of various intravenous fluids resulting in hyperchloremic acidosis and associated acute kidney injury; however, this has primarily been in the context of resuscitation and critical care, and not ward-based medical or surgical patients who receive lower volumes of infusion fluid. We aimed to determine whether normal saline use is more likely to produce hyperchloremic metabolic acidosis than compound sodium lactate, in acute general medical and surgical patients. Methods: This was a retrospective study, conducted in 2015 in a metropolitan hospital in Melbourne, Australia, and of 1,158 sequentially admitted general medical and surgical patients receiving either intravenous normal saline or compound sodium lactate. Demographics, admission diagnosis, comorbidities, and medications were compared. Serum biochemistry results 24 - 48 h post-infusion were analyzed. Primary outcome was incidence of serum hyperchloremia post-infusion. In addition, mean shift in serum chloride concentration as well as mean normalized chloride concentration (mmol/L per day per L of infusion) were calculated. Acute kidney injuries and deaths during admission were also reported. Results: A total of 221 patients (169 medical and 52 surgical patients) were included for analysis (mean age 71.6 years, 72% female), with 174 normal saline and 61 compound sodium lactate infusions. No difference in hyperchloremia rate was found (normal saline vs. compound sodium lactate; n = 8 (4.6%) vs. n = 2 (3.3%), P = 1.0). Post-infusion serum chloride concentration was also not significantly different (99.0 ± 5.1 mmol/L vs. 100.0 ± 3.4 mmol/L, P = 0.1700) between infusion groups. Normal saline infusions resulted in an increase of mean normalized chloride concentration compared to compound sodium lactate (1.2 ± 4.0 mmol/L per day/L vs. -0.3 ± 1.5, P = 0.0121). Conclusions: We conclude that 2 - 3 L normal saline infusions in this population do not appear to be associated with hyperchloremic acidosis more frequently than compound sodium lactate infusions, allaying concerns of normal saline use in wards. World J Nephrol Urol. 2018;7(2):39-44 doi: https://doi.org/10.14740/wjnu339w