Physico-chemical stability and sterility of previously prepared saline infusion solutions for use in out-of-hospital emergencies

Objective: The topic of this research was to determine whether out-of-hospital emergency teams could make use of previously prepared saline solutions (SS). The objective was to discover the physical, chemical and sterility characteristics of previously prepared saline infusions stored in ambulances and ascertain how long they remained in optimum condition. Method: Randomised clinical trial, triple blind, where study units consisted of saline solutions prepared with an infusion system and a three-way valve. The duration of the study was 12 months. Six intervention groups were designed on the basis of time of exposure and location. Samples consisted of 672 units. Twelve microbiological cultures were made and the pH, density, viscosity and CINa concentration were determined. We compared hypotheses with four models of linear regression for the variables and a model of logistic regression for the variables. A value of P