A pilot, randomized, blinded, multi-centre, feasibility, safety and biochemical and physiological study of normal saline versus plasmalyte in intensive therapy

The administration of intravenous fluid is a common intervention in acutely unwell patients. Although normal saline has been the dominant crystalloid fluid worldwide for more than century, at present, intensive care specialists in Australia and New Zealand (ANZ) broadly regard all intravenous crystalloid solutions, including normal saline and plasmalyte as equivalent. They will administer one of these two fluids for resuscitation or rehydration according to personal preference or clinical judgment in the absence of evidence that one is superior to the other in terms of clinical outcomes. Before definitive multicenter double-blind randomized controlled trials can be performed, pilot studies are necessary to guide their optimal execution. Such pilot work makes it possible to assess the following crucial aspects of trial execution: feasibility of study design, degree of biochemical and physiological separation achieved with study interventions, safety of study approach, likely recruitment rate, likely effects, likely amounts of fluids used per patient, and power calculations. Accordingly, we propose to perform a pilot multicenter randomized double-blind controlled trial to compare the feasibility, safety, biochemical and physiological effects of treating patients requiring fluid resuscitation with either normal saline or plasmalyte. On the basis of previous comparative data, we plan to study 60 patients (30 treated with saline vs. 30 treated with plasmalyte) and to use base excess during the first 4 days (when most of fluid administration takes place) in ICU as the primary outcome measure.