Purpose: To compare normal saline to heparinized normal saline in maintaining patency of peripheral intermittently accessed 24-gauge intravenous catheters in a neonatal population. Methods: In a prospective, double-blind study, forty-seven subjects were randomized to receive either benzyl alcohol-free normal saline (n=24) or benzyl alcohol-free heparinized normal saline (4 units heparin/ml) (n=23) as peripheral intravenous lock flush solution. Infusion devices were flushed using a positive pressure technique after each intravenous medication and every six hours. Setting: A level three Neonatal Intensive Care Unit in a Canadian university teaching hospital. Participants: The study population included neonates ranging in postconceptional age from 24 to 42 weeks with a mean of 35.1 weeks ± 5.4; average weight was 2664.3 ± 1175.6 grams with a range of 660 to 4860 grams.

Findings: Catheter longevity was significantly longer in the group that had catheters flushed with normal saline compared to those flushed with heparinized normal saline (p<.05). The incidence of phlebitis was similar in both groups. Post-conceptual age and weight did not differ significantly between the study groups.

Conclusion: The results of this clinical study support the use of saline as a flush solution in maintaining patency of peripheral intermittently accessed 24-gauge catheters. Further research with a larger sample of neonates and different flush techniques is recommended.