The SPLIT study, a double-bind, cluster randomised, double-crossover trial that was conducted in 4 ICUs and enrolled 2278 patients, aimed to answer a very practical question: what is the relationship between infusion of high-chloride fluids and acute kidney injury (AKI) in ICU patients? Unfortunately, the results do not answer the question.
Indeed, several limitations of the study were underlined by Kellum and Shaw in the accompanying editorial. The summary of these limitations is simple: potential toxicity (of chloride in this case) depends on the dose and on the susceptibility of the population exposed. With the inclusion of a majority of postoperative patients with moderate risk (mean APACHE 2 score of 14), a median exposure of 2 L of fluids during the entire ICU stay and no reporting of the serum chloride data, the issue remains unresolved!
Further large randomised clinical trials are necessary to finally hope to answer this question.
– Michael Piagnerelli