Neonatal and pediatric peripheral parenteral nutrition: what is a safe osmolarity?

To reach nutrition goals, peripheral parenteral nutrition (PPN) often exceeds an osmolarity (Osm) of 900 mOsm/L. Evidence suggesting PPNs with Osm > 900 mOsm/L are safe in adults. However, some pediatric data suggest the PPN Osm limit should be 500-700 mOsm/L, yet A.S.P.E.N. recommends a limit of 900 mOsm/L.

This is a retrospective cohort study from January 1, 2005, to December 31, 2007, to determine if PPNs with an Osm > 900 mOsm/L result in an increased rate of line-related events in neonatal and pediatric patients. Patients from birth to 21 years were included and grouped based on the final Osm of the PPN. The exposed group included patients with Osm > 900 mOsm/L and the nonexposed (NE) group Osm ≤ 900 mOsm/L.

Baseline demographic data were similar. The mean Osm for neonatal PPNs was 856 and 944 mOsm/L for pediatric PPNs. For neonatal PPNs, the incidence of line-related events was 50 per 100 patient days and 52 per 100 patient days for PPNs ≤ 900 and > 900 mOsm/L (RR = 1.02, 95% CI 0.88-1.18). For pediatric PPNs, the incidence of line-related events was 49.5 per 100 patient days and 42.6 per 100 patient days for PPNs ≤ 900 and > 900 mOsm/L (RR = 0.94, 95% CI 0.77-1.15).

The final Osm of PPN did not effect the rate of line-related events. Prospective studies assessing the development of line-related events, as a result of PPN Osm, are warranted to confirm the data presented in this analysis.