Neonatal electroencephalogram does not predict cognitive and academic achievement scores at early school age in survivors of neonatal extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation is an effective rescue treatment for severe cardiorespiratory failure in term or near-term neonates, although a wide range of neurologic sequelae have been noted in a substantial minority of survivors. The objective of the present study was to determine the value of the neonatal electroencephalogram (EEG) for predicting Wechler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R), Wide Range Achievement Test, and Wide Range Assessment of Memory and Language scores at early school age in 66 testable survivors of extracorporeal membrane oxygenation who were not severely brain damaged. Technically satisfactory EEG recordings were obtained at least twice following admission to our nursery and prior to discharge. The EEGs were classified and graded according to standard criteria. The developmental test results of those who had only normal or mildly abnormal neonatal EEGs (group 1, n = 9) were compared with those who had at least one moderately or markedly abnormal recording (group 2, n = 57). School-age test and subtest scores were not statistically significantly worse in group 2 versus group 1 infants. No child in group 1 and five children in group 2 had WPPSI-R Full-Scale IQ scores of less than 70. Of the nine children in group 2 who had at least one markedly abnormal neonatal EEG recording (graded as burst suppression or as electrographic seizure), only two had abnormally low WPPSI-R Full-Scale IQ scores. We conclude that EEG recordings obtained during the neonatal course of neonates treated with extracorporeal membrane oxygenation do not predict cognitive and academic achievement test results in survivors at early school age who were testable and not severely brain damaged.

Five-year follow-up of neonates with reconstructed right common carotid arteries after extracorporeal membrane oxygenation.

OBJECTIVE: Serial Doppler ultrasonography and long-term neurodevelopmental follow-up outcomes were evaluated prospectively in neonates whose right common carotid artery (RCCA) was reconstructed after extracorporeal membrane oxygenation (ECMO). METHODS: Children with RCCA reconstruction (n = 34) were monitored for 3.5 to 4.5 years by Doppler ultrasonography for arterial patency, and 28 had IQ testing by 5 years. A comparison group consisted of 35 infants who had RCCA ligation after ECMO. Neonatal electroencephalograms and computed tomography/magnetic resonance imaging scans were also compared. RESULTS: Reconstructions were successful (<50% RCCA stenosis by Doppler ultrasonography) in 26 (76%) of 34 children, 3 (9%) had >/=50% stenosis, and 5 (15%) had occlusion. No significant differences were seen between reconstructed and ligated groups in neonatal complications or ECMO courses. Occurrence of marked neonatal electroencephalographic abnormalities did not differ between groups. Abnormalities on computed tomography/magnetic resonance imaging scans (4 of 31 vs 11 of 29, P =.025) and cerebral palsy (0 of 34 vs 5 of 35, P =.054) were more common in infants with RCCA ligation. No differences were seen in developmental or IQ scores between the 2 groups, and 4 in each group had cognitive handicaps (at least 1 IQ score <70). CONCLUSIONS: Most RCCA reconstructions remained patent, with 24% showing significant stenosis or occlusion. Compared with a historical control group, patients with RCCA reconstruction had fewer brain scan abnormalities and tended to be less likely to have cerebral palsy. RCCA reconstruction after venoarterial ECMO may improve outcome.

Cerebrovascular complications and neurodevelopmental sequelae of neonatal ECMO.

A total of 355 infants have been treated with ECMO at our hospital between 1985 and 1996, 271 of whom have been enrolled in an ongoing prospective study; of the 271 infants enrolled, 223 (82%) survived, and most function within the normal range of development. Nevertheless, handicapping sequelae, including spastic forms of CP, hearing loss, and cognitive deficiencies at school age, have been noted in a significant minority of ECMO-treated survivors. The need for RCCA cannulation during venoarterial ECMO may increase the risk of a cerebrovascular injury, and lateralized CBF abnormalities have been noted on CDI and pulsed Doppler ultrasound studies during and after venoarterial bypass; however, post-ECMO CT scans, HUS, MR images, or clinical evaluations have not indicated selective or greater injury to the right, compared with the left, cerebral hemisphere in our survivors, nor was there a significant predilection for right, rather than left, cerebral hemispheric EEG abnormalities during or following venoarterial bypass. Although we routinely repair the RCCA following venoarterial ECMO, the long-term consequences of a permanently ligated artery have not as yet been demonstrated. We have noted the ominous predictive value of two or more recordings that disclose ES and BS EEG abnormalities before or during venoarterial ECMO and found that the need for vigorous CPR before or during RCCA cannulation significantly increased the risk of these two markedly abnormal bioelectric patterns. Because 85% of infants with severe respiratory failure have moderate to marked EEG abnormalities (including 23% who have BS or ES patterns) before ECMO, we believe that fetal and neonatal complications related to the occurrence and treatment of severe cardiorespiratory failure are responsible in large part for the neurologic sequelae in ECMO survivors. The risk for CP was significantly increased in survivors of neonatal venoarterial ECMO treated at our hospital who required CPR or who independently had a systolic BP below 39 mm Hg before or during ECMO. We also noted that the risk for hearing loss was increased significantly in surviving neonates who had a PaCO2 below 14 mm Hg before ECMO. The possibility that undetected confounding variables were, in part, responsible for the neurologic, audiologic, and cognitive sequelae in ECMO survivors could not be excluded entirely by our data analyses. Although the pathogenesis of severe brain damage has not been defined fully in neonates treated with ECMO, focal, multifocal, or diffuse cerebral ischemia is the most likely final common pathway; thrombosis, infarction, or hemorrhage may follow and contribute to the brain injury. The cause of isolated SNHL is unknown in most affected ECMO survivors, but in some very likely is associated with the complications and treatment of severe cardiorespiratory failure, including profound hypocarbia prior to ECMO. The results of our studies to date are consistent with the following conclusions: (1) hypotension before or during ECMO and the need for CPR before ECMO contribute to the pathogenesis of CP, probably through the mechanism of cerebral ischemia; (2) profound hypocarbia before ECMO and delayed ECMO treatment are associated with a significantly increased risk of hearing loss; (3) hypoxemia without hypotension does not result in CP; (4) the type and severity of neurologic and cognitive sequelae in ECMO survivors depends, in part, on the primary cause of the neonatal cardiorespiratory failure; (5) early neurodevelopment, except for severe deficits, may not predict school-age performance; and (6) abnormally low or borderline WPPSI-R IQ scores and academic deficiencies at early school age, without evidence of a congenital abnormality of brain or CP or SNHL, remain unexplained. The criteria for initiating ECMO in the neonate with severe cardiorespiratory failure include decreasing oxygenation despite mechanical hyperventilation with 100% oxygen. (ABSTRACT TRUNCATED)

Clinical antecedents of neurologic and audiologic abnormalities in survivors of neonatal extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation is an effective rescue treatment for severe cardiorespiratory failure in term or near term neonates, although cerebral palsy, mental retardation, and sensorineural hearing loss are observed in 10 to 20% of survivors. The objective of the present study was to identify potential risk factors that may explain the neurologic and audiologic sequelae noted in 19% of 181 survivors of neonatal extracorporeal membrane oxygenation from our hospital. Our results suggest the following findings in survivors of severe cardiorespiratory failure treated with neonatal extracorporeal membrane oxygenation: (1) hypotension or the need for cardiopulmonary resuscitation before extracorporeal membrane oxygenation significantly increases the risk of spastic cerebral palsy, (2) profound hypocarbia before extracorporeal membrane oxygenation is associated with a significantly increased risk of hearing loss, (3) mental retardation in the absence of spastic cerebral palsy is unexplained except when due to abnormal fetal brain development, and (4) hypoxemia in the absence of hypotension does not increase the risk of neurologic or audiologic sequelae.