Motor, cognitive and behavioural outcomes after neonatal hypoxic-ischaemic encephalopathy

INTRODUCTION

The current neurodevelopmental status of patients with neonatal hypoxic-ischaemic encephalopathy (HIE) in Spain is unknown. Recent European studies highlight a shift of severe pathology towards mild motor disorders and emotional problems. The aim of this study was to analyse neurodevelopmental outcomes in a cohort of neonates with HIE at age 3 years.

PATIENTS AND METHOD

Multicentre observational study of neonates born at 35 or more weeks of gestation with moderate to severe HIE in 2011-2013 in 12 hospitals in a large Spanish region (91 217 m2), with the recruitment extended through 2017 in the coordinating hospital. We analysed the findings of neonatal neuroimaging and neurodevelopmental test scores at 3 years (Bayley-III, Peabody Picture Vocabulary Test and Child Behavior Checklist). The sample included 79 controls with no history of perinatal asphyxia.

RESULTS

Sixty-three patients were recruited, of whom 5 (7.9%) were excluded due to other pathology and 14 (24%) died. Of the 44 survivors, 42 (95.5%) were evaluated. Of these 42, 10 (24%) had adverse outcomes (visual or hearing impairment, epilepsy, cerebral palsy or developmental delay). Other detected problems were minor neurological signs in 6 of the 42 (14%) and a higher incidence of emotional problems compared to controls: introversion (10.5% vs. 1.3%), anxiety (34.2% vs. 11.7%) and depression (28.9% vs. 7.8%) (P < .05). The severity of the lesions on neuroimaging was significantly higher in patients with motor impairment (P = .004) or who died or had an adverse outcome (P = .027).

CONCLUSION

In addition to classical sequelae, the followup of patients with neonatal HIE should include the diagnosis and treatment of minor motor disorders and social and emotional problems.

Adherence to hypothermia guidelines in newborns with hypoxic-ischemic encephalopathy

INTRODUCTION

We do not have population data in Spain on the application of therapeutic hypothermia (TH). The objective was to examine adherence to management standards during TH of infants with hypoxic-ischemic encephalopathy (HIE).

METHOD

Multicenter observational cohort study from the beginning of TH (year 2010) in 5 hospitals in a Spanish region, until year 2019.

RESULTS

133 patients were recruited, 72% diagnosed with moderate HIE and the rest of them with severe HIE. In 84% of infants, passive hypothermia was started at birth. Active TH was started at a median age of 5 h of life (IQR 3.3; 6.3), although the central targeted temperature (33-34 °C) was reached at a median age of 3.5 h (IQR 1; 6). Those born extramural, initiated active TH 3.3 h on average later than those born intramural, but without differences in the age at which the targeted temperature was reached. Sedoanalgesia was used in 97%. 100% were monitored with amplitude-integrated EEG and 59% with cerebral oxymetry. MRI was performed in 94% with moderate HIE vs. 65% with severe; P < .001. Neuron-specific enolase in cerebrospinal fluid was determined in 42%. The average duration of rewarming was median 10 h (IQR 8; 12), with no differences depending on the degree of HIE (P = .57).

CONCLUSIONS

The implementation of TH successfully met the standards. However, aspects of care that could be improved were detected. Auditing newborn care with HIE is crucial to achieving programs with a high quality of care in each region.

[Adherence to hypothermia guidelines in newborns with hypoxic-ischemic encephalopathy]

INTRODUCTION

We do not have population data in Spain on the application of therapeutic hypothermia (TH). The objective was to examine adherence to management standards during TH of infants with hypoxic-ischemic encephalopathy (HIE).

METHOD

Multicenter observational cohort study from the beginning of TH (year 2010) in 5 hospitals in a Spanish region, until year 2019.

RESULTS

133 patients were recruited, 72% diagnosed with moderate HIE and the rest of them with severe HIE. In 84% of infants, passive hypothermia was started at birth. Active TH was started at a median age of 5hours of life (IQR: 3.3-6.3), although the central targeted temperature (33-34°C) was reached at a median age of 3.5hours (IQR: 1-6). Those born extramural, initiated active TH 3.3hours on average later than those born intramural, but without differences in the age at which the targeted temperature was reached. Sedoanalgesia was used in 97%. The 100% were monitored with amplitude-integrated EEG and 59% with cerebral oxymetry. MRI was performed in 94% with moderate HIE vs. 65% with severe; P<.001. Neuron-specific enolase in cerebrospinal fluid was determined in 42%. The average duration of rewarming was median 10hours (IQR: 8-12), with no differences depending on the degree of HIE (P=.57).

CONCLUSIONS

The implementation of TH successfully met the standards. However, aspects of care that could be improved were detected. Auditing newborn care with HIE is crucial to achieving programs with a high quality of care in each region.

Usefulness of video recordings for validating neonatal encephalopathy exams: a population-based cohort study

OBJECTIVE

To determine the usefulness of video recordings for validating neonatal encephalopathy (NE) exams.

DESIGN

Population-based prospective cohort study. NE was assessed and recorded at 1, 3 and 5 hours after birth by the attending physician. Recordings were reviewed blindly after the recruitment period by two specialists. Outcome was assessed at 36 months of age.

SETTING

Twelve intensive care units in Spain.

PATIENTS

Infants of ≥35 weeks' gestational age with perinatal asphyxia.

MAIN OUTCOMES MEASURES

Weighted kappa to measure disagreement between the two specialists and between the attending physician and the specialists' classification agreed on by consensus. Regression models to test the association of disagreement on NE assessment and outcome.

RESULTS

Of the 32 325 liveborn infants, 217 met the inclusion criteria. Video-recordings were not available for 43 infants (20%). Weighted kappa statistic was 0.74 (95% CI 0.67 to 0.81) between the specialists and the attending physicians. Disagreement occurred in 93 of the 417 (22%) videos, specifically in 39 (14%), 43 (47%), 11 (34%) and 0 exams categorised as no, mild, moderate and severe NE, respectively. According to the specialist consensus assessment, there was disagreement on the therapeutic hypothermia decision in 10 infants.When there was consensus among the specialists assessing a more severe NE degree compared with the attending physicians in 170 infants, those infants had lower cognitive scores with a median of -5.33 points (95% CI -9.85 to -8.16; p=0.02).

CONCLUSIONS

This study supports the feasibility and benefit of using video recordings to identify NE in infants with perinatal asphyxia.

[Inter-observer reliability for amplitude-integrated EEG in the newborn with perinatal asphyxia]

INTRODUCTION

Amplitude integrated electroencephalography (aEEG) is a widely tool used for neuromonitoring in the critical neonate. In the patient with perinatal asphyxia, its interpretation is key to identifying candidates for therapeutic hypothermia, detecting subclinical seizures and providing pronostic information. Our aim was to analyze the concordance in the interpretation of aEEG among neonatologists with different level of experience.

MATERIAL AND METHODS

Unicenter retrospective study of newborns ≥35 weeks with perinatal asphyxia included consecutively over a two-year period and monitored with aEEG for at least 6h. The bedside neonatologist interpreted aEEG regarding background pattern, sleep-wake cycling, and seizures. The aEEG tracings were blindly reviewed by two neonatologists with different experience. The aEEG tracings were divided into periods of 0-3h and 3-6h of life, and the concordance (Cohen Kappa coefficient, k), between the two examiners and that of their consensus with the bedside neonatologist, was analyzed.

RESULTS

Seventy-five newborns were included, 5 of them were not aEEG-monitored. 132 tracings were analyzed with a very good concordance between the two examiners in the three characteristics of the aEEG. The k for the bedside neonatologist was very good for background pattern (k=0.93), moderate (k=0.52) for sleep-wake cycling, and weak (k=0.32) for seizures.

CONCLUSIONS

This study supports that background pattern is easily interpreted compared to sleep-wake cycling or crisis, improving when targeted training on aEEG is received.

Temporal Trends in the Severity and Mortality of Neonatal Hypoxic-Ischemic Encephalopathy in the Era of Hypothermia

INTRODUCTION

There is a paucity of studies examining temporal trends in the incidence and mortality of moderate-to-severe hypoxic-ischemic encephalopathy (HIE) during the last decade of therapeutic hypothermia (TH).

METHODS

Multicenter cross-sectional study of all infants ≥35 weeks gestational age diagnosed with moderate-to-severe HIE within 6 h of birth in an extensive region of Spain between 2011 and 2019, in order to detect trend changes over time in the (1) annual incidence, (2) severity of neurological and systemic organ involvement, and (3) neonatal death from HIE.

RESULTS

Annual incidence rate of moderate-to-severe HIE was 0.84 (95% confidence interval [CI] 0.7-0.97) per 1,000 births, without trend changes over time (p = 0.8), although the proportion of severe HIE infants showed an average annual decline of 0.86 points (95% CI 0.75-0.98). There were 102 (70%) infants diagnosed with moderate HIE and 44 (30%) with severe HIE. TH was offered to 139/146 (95%) infants. Infants with clinical and/or electrical seizures showed a decreasing trend from 56 to 28% (p = 0.006). Mortality showed a nonstatistically significant decline (p = 0.4), and the severity of systemic damage showed no changes (p = 0.3). Obstetric characteristics remained unchanged, while higher perinatal pH values (p = 0.03) and Apgar scores (p = 0.05), and less need for resuscitation (p = 0.07), were found over time.

CONCLUSION

The annual incidence of moderate-to-severe HIE has stabilized at around 1 per 1,000 births, with a temporal trend toward a decrease in severe HIE infants and a slight decline of mortality. No association was found between temporal trends and changes in perinatal/obstetric characteristics over time.

Lack of Variability in Cerebral Oximetry Tendency in Infants with Severe Hypoxic-Ischemic Encephalopathy Under Hypothermia

Cerebral oximetry using near-infrared spectroscopy (NIRS) provides continuous, noninvasive assessment of the degree of hemoglobin saturation of the brain tissue. Previous studies suggest that high values of regional cerebral tissue oxygen saturation (rScO₂) during the first days in neonates with significant hypoxic-ischemic encephalopathy (HIE) are correlated with an adverse neurological outcome. However, the results are not consistent among the studies. To examine the correlation of rScO₂ values and their variability over time with HIE severity, amplitude integrated electroencephalography (aEEG) background and seizure activity, neuron-specific enolase levels in cerebrospinal fluid, magnetic resonance imaging (MRI) findings, and neurological outcome. Retrospective study that included all consecutive infants with moderate-to-severe HIE born at ≥35 weeks gestational age admitted between January 2011 and December 2014. NIRS monitoring was initiated at admission and maintained during therapeutic hypothermia up to 12 hours after rewarming. To analyze rScO₂, different periods (0-6, 6-24, 24-48, 48-72, and 72-100 hours of life) and three ranges (<55%, 55-90%, >90%) were considered. Variability in each patient was considered ≤5% when changes in rScO₂ values in all periods were ≤5%. Twenty-three newborns were included. Infants who suffered from severe HIE, seizures, abnormal aEEG background, altered MRI or death, and abnormal outcome had rScO₂ values >90% and with less variability (≤5%). rScO₂ values >90% and a lack of variability over time in infants with HIE during cooling provide useful information about the severity of neurological status.