Hypocarbia and adverse outcome in neonatal hypoxic-ischemic encephalopathy.


Journal Article

OBJECTIVE: To evaluate the association between early hypocarbia and 18- to 22-month outcome among neonates with hypoxic-ischemic encephalopathy. STUDY DESIGN: Data from the National Institute of Child Health and Human Development Neonatal Research Network randomized, controlled trial of whole-body hypothermia for neonatal hypoxic-ischemic encephalopathy were used for this secondary observational study. Infants (n = 204) had multiple blood gases recorded from birth to 12 hours of study intervention (hypothermia versus intensive care alone). The relationship between hypocarbia and outcome (death/disability at 18 to 22 months) was evaluated by unadjusted and adjusted analyses examining minimum PCO(2) and cumulative exposure to PCO(2) <35 mm Hg. The relationship between cumulative PCO(2) <35 mm Hg (calculated as the difference between 35 mm Hg and the sampled PCO(2) multiplied by the duration of time spent <35 mm Hg) and outcome was evaluated by level of exposure (none-high) using a multiple logistic regression analysis with adjustments for pH, level of encephalopathy, treatment group (± hypothermia), and time to spontaneous respiration and ventilator days; results were expressed as odds ratios and 95% confidence intervals. Alternative models of CO(2) concentration were explored to account for fluctuations in CO(2). RESULTS: Both minimum PCO(2) and cumulative PCO(2) <35 mm Hg were associated with poor outcome (P < .05). Moreover, death/disability increased with greater cumulative exposure to PCO(2) <35 mm Hg. CONCLUSIONS: Hypocarbia is associated with poor outcome after hypoxic-ischemic encephalopathy.

Full Text

Duke Authors

Cited Authors

  • Pappas, A; Shankaran, S; Laptook, AR; Langer, JC; Bara, R; Ehrenkranz, RA; Goldberg, RN; Das, A; Higgins, RD; Tyson, JE; Walsh, MC; Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network,

Published Date

  • May 2011

Published In

Volume / Issue

  • 158 / 5

Start / End Page

  • 752 - 758.e1

PubMed ID

  • 21146184

Pubmed Central ID

  • 21146184

Electronic International Standard Serial Number (EISSN)

  • 1097-6833

Digital Object Identifier (DOI)

  • 10.1016/j.jpeds.2010.10.019


  • eng

Conference Location

  • United States