Heparin in Peripheral IVs
Benefit and risk of heparin for maintaining peripheral venous catheters in neonates: A placebo-controlled trial. Klenner AF, Fusch C, Rakow A, et al. J Pediatr 2003; 143: 741-5.
Objectives
Heparin addition to infusion fluids is used to prolong catheter patency in
newborns. Heparin may also induce adverse effects such as bleeding
complications and immune-mediated heparin-induced thrombocytopenia (HIT). One
objective was peripheral venous catheter patency with heparinization of
continuous infusions (0.5 IU/mL). Secondary objectives were incidences of
bleeding, clinically manifest HIT, HIT antibodies, and catheter-related
complications.
Study design Inclusion criteria were anticipated need for intravenous
peripheral infusion (
5
days for HIT-related endpoints) and postnatal age <28 days at study entry.
Exclusion criteria were bodyweight <1000 g, congenital malformation, need for
therapeutic anticoagulation or mechanical ventilation, and severe bleeding.
HIT antibodies were assessed by enzyme-linked immunosorbent assay.
Results A total of 145 infants received heparin, and 151 infants
received saline. Patient characteristics, number of additional drugs, duration
of treatment, and location and size of catheters did not differ. Patency of
catheters was 7.4 hours longer in the heparin group (33.8 hours vs 26.4 hours,
P<.0001), but the total numbers of catheters did not differ (565 vs
692, P=.3). No infant developed HIT antibodies. Incidences of bleeding
complications and thrombocytopenia were comparable between groups.
Conclusions Balancing the benefits against the risks of heparin
addition and the rare complication of HIT, we will not use 0.5 IU/mL heparin
addition to parenteral fluids.
Comments:
Adding heparin to
peripheral IV solutions in neonates extends catheter patency by an average
of 7 hours. This result, while highly significant statistically, has little
clinical significance since the total number of catheters needed was no
different between groups. In view of the significant potential for serious
medication errors involving heparin in neonates, I agree with the authors
that the risks of this practice outweigh the benefits. Similar results were
found for “heparin locks” in neonates, and I suspect that most of us now
flush these catheters with normal saline rather than heparin. What about
umbilical lines and central venous catheters? Should we re-think adding
heparin to these? ABK