Hemodynamic effects of sodium bicarbonate administration.

OBJECTIVE

To describe the hemodynamic changes that occur with sodium bicarbonate (NaHCO) administration in premature neonates.

STUDY DESIGN

This retrospective study included premature neonates 23 to 31+6 weeks of gestational age who underwent continuous cardiac and cerebral monitoring as participants in prospective trials at our institution, and who received NaHCO infused over 30 min in the first 24 h of life. Blood pressure (BP), heart rate, cardiac output (CO), SpO and cerebral oximetry (StO) were captured every 2 s. A baseline was established for all continuous data and averaged over the 10 min before NaHCO administration. Baseline was compared with measurements over 10 min epochs until 80 min after administration. Arterial blood gases before and within 1 h of administration were also compared. Significance was set at P<0.05.

RESULTS

A total of 36 subjects received NaHCO (1.3±0.3 mEq kg) in the first 24 h (14±8.5 h) of life. NaHCO administration increased pH (7.23 vs 7.28, P<0.01) and decreased base deficit (-8.9 vs -6.8, P<0.01) and PaCO (45 vs 43 mm Hg, P<0.05). There was a transient but significant (P<0.05) decrease in systemic BP coinciding with an increase in cerebral oxygenation without an increase in oxygen extraction. CO did not change.

CONCLUSION

Early postnatal NaHCO administration does not acutely improve CO but does cause transient fluctuations in cerebral and cardiovascular hemodynamics in extremely premature infants.