UMEM Educational Pearls

Background: Interest in moving to balanced fluid administration has grown after publication of the SPLIT trial and SALT-ED/SMART trials, which showed respectively evidence of benefit to balanced crystalloid over normal saline on mortality and major adverse kidney events at 30 days.

Population/Intervention: The BaSICs trial is an RCT in 75 ICUs in Brazil, testing P-Lyte versus NS (with each arm getting two different infusion rates that were analyzed as a separate trial) for volume administration per protocol.

--10,520 ICU patients requiring fluid expansion, expected ICU stay >1 day, and 1 additional risk factor for AKI (age>65, hypotension, sepsis, MV, NIV, oliguria, elevated creatinine, cirrhosis, or acute liver failure).

--Exclusions: severe dysnatremia, expected RRT within 6 hours, expected death.

--Average age was 61, with a SOFA score of 4, and 48% on were elective surgical admissions.


--No difference in 90 days mortality (P-Lyte 26.4% v NS 27.2, aHR p=0.47), AKI or RRT out to 7-days, or in duration of MV, ICU LOS or hospital LOS

--Median study fluid by day 3 was 2.9L in each group

--Higher neurological SOFA score observed in P-Lyte group

--Higher mortality seen with P-Lyte in TBI subgroup (P-Lyte 31.3% vs NS 21.1%, p=0.02)


--Adds contrasting negative data to previous large positive RCTs showing benefit of balanaced fluids

--Expect further reanalysis/metanalysis of BSS versus NS trials

--Signal for harm in TBI pts with P-Lyte correlates with SMART point estimates that were not significant

--Compared to SMART trial population BaSICs had: 2x higher mortality, more planned surgery, received about 1L more study fluid in the first 3ds


--Balanced crystalloid versus normal saline debate will continue considering this large negative trial

--Signal for possible harm in TBI population with balanced crystalloids compared to normal saline



  1. BaSICs Trial. DOI: 10.1001/jama.2021.11684
  2. SMART Trial. DOI: 10.1056/NEJMoa1711584