Similar outcomes between lactated Ringer’s and normal saline for hospitalized patients

1. Among randomized hospitalized patients in this trial, routine use of lactated Ringer’s (LR) solution did not reduce the risk of death or re-hospitalization compared to normal saline (NS).

2. No serious adverse events associated with either intervention were reported.

Evidence Rating Level: 1 (Excellent)

Study Rundown: Crystalloid fluids, most commonly LR and NS, are a first-line intervention for hospitalized patients to treat hemodynamic instability and maintain balanced fluid status. LR and other balanced crystalloids contain less chloride than saline and carry less risk of hyperchloremic acidosis. However, evidence is conflicting regarding the impact of balanced crystalloids versus NS on the risk of mortality and renal adverse events in both critical and non-critical settings. This cluster-randomized trial compared LR against NS as the primary crystalloid fluid for hospital-wide use among admitted patients. Following two 12-week sequences of either LR-then-NS or NS-then-LS, interspersed by a washout period, no significant difference was found in the composite and individual risks of death or readmission within 90 days of the index admission. There was also no difference in hospital length of stay, dialysis initiation, re-presentation to the emergency department, or discharge to destinations other than home. No serious adverse events were associated with either intervention. Overall, these results suggested that routine use of LR, compared to NS, among admitted patients did not impact the incidence of death or readmission within 90 days.

Click here to read the study in NEJM

Relevant Reading: Balanced Multielectrolyte Solution versus Saline in Critically Ill Adults

In-Depth [randomized controlled trial]: This was an open-label, two-period, two-sequence, cluster-randomized, crossover trial conducted at seven hospitals in Ontario, Canada, comparing hospital-wide LR or NS use for admitted patients. Eligible hospitals admitted at least 1,500 patients per trial period and had level II or III ICU capacity. All patients with an index admission during the trial period were eligible for inclusion, defined as a patient’s first hospitalization within the preceding 90 days. Exclusion criteria included age less than one month, missing a birth date, or admission not meeting the definition of an index admission, or admission during the run-in and wash-out periods. The trial included 43,626 eligible patients from seven hospitals. Hospitals (clusters) were randomly assigned to implement a hospital-wide policy of using either lactated Ringer’s solution or normal saline for 12 weeks, after which they switched to the other fluid for a second 12-week period. The primary outcome was a composite of death or hospital readmission within 90 days after the index admission. The mean (±SD) incidence of death or 90-day readmission was 20.3±3.5% in the LR group and 21.4±3.3% in the NS group (adjusted difference -0.53 percentage points, 95% Confidence Interval [CI], -1.85 to 0.79; p=0.35). Similarly, the adjusted mean difference was -0.26 percentage points (95% CI -0.95 to 0.43) for death within 90 days, -0.12 percentage points (95% CI -0.34 to 0.11), and -0.12 percentage points (95% CI -0.34 to 0.11). No significant differences were observed in other secondary outcomes either. No serious adverse events related to the administration of either trial fluid were reported. In summary, these results showed that routine use of LR, compared to NS, among admitted patients did not significantly impact the risk of death or risk of readmission within 90 days.

Image: PD

©2025 2 Minute Medicine, Inc. All rights reserved. No works may be reproduced without expressed written consent from 2 Minute Medicine, Inc. Inquire about licensing here. No article should be construed as medical advice and is not intended as such by the authors or by 2 Minute Medicine, Inc.