Heparin and infusion phlebitis: a prospective study

OBJECTIVE: To determine whether heparin sodium, when added to fluids infused through a peripheral catheter, reduces some local catheter-related problems (i.e., phlebitis, catheter obstruction, and extravasation of fluid) and extends the catheter's useful life. DESIGN: Prospective, double-blind, placebo-controlled. SETTING: Internal medicine ward of a general hospital with 400 beds. PATIENTS: Eighty-one consecutive acute collaborating patients who had a venous catheter in the forearm, inserted by nurses with more than one year of professional experience. INTERVENTION: Heparin sodium 1000 units/mL or NaCl 0.9% was added to compatible infusion fluids just before they were given to the patients. The final concentration of heparin was 1 unit/mL. MEASUREMENTS: Length of time until catheters were removed and reasons for their removal. RESULTS: The heparin group had a lower rate of local catheter-related problems than the placebo group (34.3 vs. 61.5 percent, respectively, p less than 0.05; 95 percent confidence interval for the difference 4.3 to 50.1 percent). The catheter's mean life in the heparin group was longer than that of placebo group (98.9 +/- 55.2 vs. 66.2 +/- 47.2 h, respectively, p less than 0.05; 95 percent confidence interval for the difference 9.15 to 56.25 h). This effect was mainly attributable to prevention of noninflammatory catheter-related problems (e.g., obstruction, extravasation) and to a delay in the appearance of phlebitis. CONCLUSIONS: Heparin sodium, when added to infusion fluids to a final concentration of 1 unit/mL, diminishes local intravenous catheter-related problems and extends the catheter's life.