These authors conduct a randomized prospective trial in which they prove that 100 patients in each arm is not enough to make valid claims about a secondary endpoint for which the study was not designed to evaluate. There is no difference between groups in mortality - and not even non-significant trends - but a small, significant, absolute difference in neurologic impairment, 4.9% without neurologic impairment in the control group and 13% in the intervention group.
So, another study suggesting further study is needed. If anything, it demonstrates how impossibly hard it is to evaluate treatments in the heterogenous population of out-of-hospital cardiac arrest, and to ensure internal and external validity.
"Randomised study of hypertonic saline infusion during resuscitation from
out-of-hospital cardiac arrest."