Study Design Summary: Single center study of 13,347 non-critically ill patients treated with either balanced crystalloid or saline in the emergency department, with a primary outcome of hospital free days.
Notes: The two groups of saline vs balanced crystalloid (lactated ringers or plasma-lyte A) were balanced in their baseline characteristics including baseline serum Cr and electrolytes. Both groups got a mean volume of fluids around 1.6 L and a median volume of 1 L. The study was patients who received at least 500cc of fluid in the ED and were admitted. The trial only included ED squid administration and did not extend to what fluids the patients got once admitted. This study also included only patients admitted to general medical wards, patients admitted to the ICU were examined separately in the SMART trial. Only 84% of the patients in the balanced crystalloid group received as compared to the 93% in the saline group.
The primary outcome was hospital free days to day 28 from randomization. For this outcome there was no difference between the groups. There were predefined secondary outcomes that mainly centered on kidney function. There were more adverse kidney events in the saline group (5.6% vs 4.7% p=0.01). In hospital was similar between the two groups.
While the study was negative and is reported as such, it is important to note that the study fluids were only the fluids administered in the ED and once the patients were admitted that fluid was no longer controlled. Also, a large percentage of the balanced crystalloid group received saline. The primary outcome of hospital free days is a complex endpoint and is not the best primary outcome for this study. If they had controlled the fluid throughout the hospital stay then this primary outcome would be more appropriate. The median and mean amount of fluid for each group was less than 2 liters. The secondary outcomes suggesting more adverse kidney events in the saline group is hypothesis generating only and does not provide any direct evidence. Also, as noted by REBEL EM, 35% of patients had an unknown baseline Cr thus a true analysis of adverse kidney events is not known as a large percentage had unknown baseline and in the study these patients were assumed to have normal Cr at baseline.
Study Conclusion: There is no difference in hospital free days among non-ICU patients treated with saline as opposed to balanced crystalloid.
Fusion Beat Bottom Line Impression: There is no difference in hospital free days in non-critically ill patients who receive saline or balanced crystalloid in the ED. This study does not support balanced crystalloid or saline as a superior resuscitation fluid when given in the ED.
A Fusion Beat 