Acid-Base Parameters for Predicting Magnetic Resonance Imaging Measures of Neurologic Outcome after Perinatal Hypoxia-Ischemia: Is the Strong Ion Gap Superior to Base Excess and Lactate?

Christian Mann; Beatrice Latal; Beth Padden; Ianina Scheer; Georg Goebel; Vera Bernet

doi:10.1055/s-0031-1300969

American Journal of Perinatology, Table of Contents

Am J Perinatol 2012; 29(05): 361-368
DOI: 10.1055/s-0031-1300969

Original Article

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Acid-Base Parameters for Predicting Magnetic Resonance Imaging Measures of Neurologic Outcome after Perinatal Hypoxia-Ischemia: Is the Strong Ion Gap Superior to Base Excess and Lactate?

Authors

Christian Mann

¹Neonatal and Pediatric Intensive Care Unit, Graubuenden Cantonal Hospital, Chur, and College for Intensive Care, Emergency and Anesthesia Nursing, University Children's Hospital Zurich, Zurich, Switzerland
Beatrice Latal

²Child Development Center, University Children's Hospital Zurich, Zurich, Switzerland
Beth Padden

³Rehabilitation Center, University Children's Hospital Zurich, Zurich, Switzerland
Ianina Scheer

⁴Department of Pediatric Radiology, University Children's Hospital Zurich, Zurich, Switzerland
Georg Goebel

⁵Department of Medical Statistics, Informatics and Health Economics, Medical University of Innsbruck, Innsbruck, Austria
Vera Bernet

⁶Department of Neonatology, University Children's Hospital Zurich, Zurich, Switzerland

Abstract

We conducted this study to compare the strong ion gap (SIG) with base excess (BE) and lactate for predicting neurologic outcome measured by magnetic resonance imaging (MRI) in newborns with hypoxic-ischemic encephalopathy (HIE). In a retrospective cohort of 39 newborns with HIE treated with whole-body surface cooling (n = 17) and no cooling (n = 22), we measured blood SIG, BE, and lactate at 4, 24, and 48 hours after birth, and determined cerebral injury severity by T1-, T2-, and diffusion-weighted MRI scores at age 5 days. Lower SIG levels correlated with better neurologic outcome. The highest correlation coefficient (0.63) was in the “no cooling” subcohort between diffusion-weighted scores and SIG levels at 24 hours; the latter also had the highest area under the receiver operating characteristic curve (AUC), 0.90, with positive and negative predictive values of 84 and 90%. SIG outperformed lactate in the “no cooling” subcohort, and vice-versa in the “cooling” subcohort. All BE AUCs were <0.6. Overall, the SIG is similar to lactate as a prognostic parameter. BE levels at 4, 24, and 48 hours after birth do not predict neurologic outcome. While not displacing lactate the SIG is an additional prognostic parameter for newborns in the first 2 days after hypoxia-ischemia.

Keywords

acidosis - asphyxia neonatorum - cerebral palsy - hypoxia-ischemia - magnetic resonance imaging - strong ion gap

Full Text

References

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