Evaluation of four methods of warming intravenous fluids.

OBJECTIVE

The purpose of this in vitro study was to compare four methods of warming intravenous fluid (IVF) with a control of unwarmed IVF at flow rates of 200, 400, 600, 800, and 1000 ml/hr.

DESIGN

A 5 x 5 factorial experimental design was used to evaluate the methods of warming IVF and the control at varied flow rates.

METHODS

The methods of warming IVF in this study included the following: (1) the Level 1 System 250 fluid warmer with D-60HL tubing (Level 1 Technologies, Inc., Rockland, Mass.); (2) the Level 1 System 250 fluid warmer with D-50 tubing (Level 1 Technologies, Inc.); (3) the Hotline fluid warmer with L-70 tubing (Level 1 Technologies, Inc.); and (4) the Baxter DW 1000 D blood fluid warmer with blood cuff set tubing (Baxter Healthcare Corporation, Valencia, Calif.). The IVF temperatures were measured with thermocouples at three points: (1) in the intravenous solution bag, (2) in the tubing after the infusion pump, and (3) 2 cm proximal to the end of the tubing. Ambient temperature and the temperature at the three measurement points were recorded when the temperature at the point 2 cm proximal to the end of the tubing was stable for 3 minutes.

RESULTS

With single-lumen tubing, fluids flowing at low rates (e.g., 200 ml/hr) were barely warm at the end of the tubing. In contrast, fluid warmed with triple-lumen technology was consistently kept warm throughout the tubing.