Extracorporeal Membrane Oxygenation for Neonates With Congenital Diaphragmatic Hernia: Prevalence of Seizures and Outcomes

OBJECTIVES

We aimed to determine the prevalence of electrographic seizures and associated odds of adverse outcomes of electrographic seizures in neonates with congenital diaphragmatic hernia (CDH) receiving extracorporeal membrane oxygenation (ECMO).

DESIGN

Retrospective, descriptive case series.

SETTING

Neonatal ICU (NICU) in a quaternary care institution.

PATIENTS

All neonates with CDH receiving ECMO undergoing continuous electroencephalographic monitoring (CEEG) and follow-up between January 2012 and December 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

All eligible neonates with CDH receiving ECMO underwent CEEG (n = 75). Electrographic seizures occurred in 14 of 75 (19%): they were exclusively electrographic-only in nine of 14, both electrographic-only and electroclinical in three of 14, and electroclinical only in two of 14. Two neonates developed status epilepticus. We identified an association between presence of seizures, rather than not, and longer duration of initial session of CEEG monitoring (55.7 hr [48.2-87.3 hr] vs 48.0 hr [43.0-48.3 hr]; p = 0.001). We also found an association between presence of seizures, rather than not, and greater odds of use of a second CEEG monitoring (12/14 vs 21/61; odds ratio [OR], 11.43 [95% CI, 2.34-55.90; p = 0.0026). Most neonates with seizures (10/14), experienced their onset of seizures more than 96 hours after the start of ECMO. Overall, the presence of electrographic seizures, compared with not, was associated with lower odds of survival to NICU discharge (4/14 vs 49/61; OR 0.10 [95% CI 0.03 to 0.37], p = 0.0006). Also, the presence of seizures-rather than not-was associated with greater odds of a composite of death and all abnormal outcomes on follow-up (13/14 vs 26/61; OR, 17.5; 95% CI, 2.15-142.39; p = 0.0074).

CONCLUSIONS

Nearly one in five neonates with CDH receiving ECMO developed seizures during the ECMO course. Seizures were predominantly electrographic-only and when present were associated with great odds of adverse outcomes. The current study provides evidence to support standardized CEEG in this population.

Erythropoietin and cord blood haemoglobin in the regulation of human fetal erythropoiesis

Erythropoietin was estimated by radioimmunoassay in serum from 78 cord blood samples, collected in the second and third trimesters in 72 pregnancies. In 43 samples obtained during or after normal pregnancy (from 19 to 42 weeks gestation) erythropoietin levels increased with gestation. Cord blood haemoglobin also increased with gestation, but the rate of increase was less during the last weeks of pregnancy. Erythropoietin levels were similar in the cord blood of infants of the same gestation, whether born vaginally or by caesarean section. The fetus can respond to severe anaemia or hypoxia with increased erythropoietin levels as early as 24 weeks gestation. Elevated erythropoietin levels were found in two out of eight infants born after labour in which there was 'acute' fetal distress, suggesting the presence of unrecognized chronic fetal hypoxia in these pregnancies.

Changes in serum immunoreactive erythropoietin during the menstrual cycle and normal pregnancy

Immunoreactive erythropoietin was estimated in samples of serum collected during the follicular and luteal phases of the menstrual cycle in seven women and in sera collected sequentially throughout normal pregnancy in these and three other women. Estimates of serum erythropoietin during the follicular and luteal phases of the menstrual cycle were almost identical. During pregnancy in all 10 subjects serum erythropoietin increased at some time after 8 weeks gestation. These changes were not related to other endocrine values, to indicators of haematological and renal function or to infant birthweight except that changes in serum erythropoietin and placental lactogen were related (P less than 0.00001). In one other woman treated over 17 weeks of pregnancy with continuous intravenous infusion of salbutamol, erythropoietin levels were within the range found in normal pregnancies.