Medicina neonatal y pediátrica

Abstracto

Cerebral Oxygenation Using Near-infrared Spectroscopy (NIRS) before, during and after Therapeutic Hypothermia: A Comparison of Cerebral Saturations between those Infants on Sedatives and Anti-Epileptics and those who are not, all of whom are Undergoing Cooling

Dixon CM and Rais-Bahrami K

Objectives: The aims of this study include the following: to determine the effect of therapeutic hypothermia (Cooling) on cerebral saturations using Near Infrared Spectroscopy (NIRS) before, during and after therapeutic hypothermia; to compare these values between infants receiving sedative and anti-epileptic medications and those who do not.

Methods: This study is a retrospective chart review of patients from Children’s National Medical Center (CNMC) Neonatal Intensive Care Unit (NICU) who underwent therapeutic hypothermia with NIRS monitoring from July 2009- December 2014. Cerebral tissue saturations (StO2) using NIRS tissue oximeter (FORE-SIGHT, CAS Medical Systems, Branford, CT, USA) were assessed during the cooling period. StO2 were periodically recorded during 3 phases: before cooling was started, during cooling, and after cooling (30 minutes of rewarming) and averaged to a composite value for each event. Data was then compared based on whether the patient received sedatives and/or anti-epileptic medications.

Results: Complete data sets were obtained for 57 subjects, weighting 1.8 kg-4.9 kg, 1-7 days old and gestational age 35.6-42.0 weeks. Cerebral tissue saturations were significantly higher during cooling (paired t-test). Those on Phenobarbital and/or Versed had significantly higher saturations compared to those on no medications. Those on only Phenobarbital also had significantly higher saturations, but to a lesser degree. Subjects where StO2 failed to rise during cooling had a higher chance of dying, perhaps due to critical brain tissue damage from lack of oxygen during birth asphyxia, or failure to recover thereafter.

Conclusions: Data from this study suggests that cerebral tissue saturations increase during therapeutic hypothermia, likely due to suppressed cerebral metabolism. Those on anti-seizures medications