RESUMEN
Importance: Compared with normothermia, hypothermia has been shown to reduce death or disability in neonatal hypoxic ischemic encephalopathy but data on seizures during rewarming and associated outcomes are scarce. Objective: To determine whether electrographic seizures are more likely to occur during rewarming compared with the preceding period and whether they are associated with abnormal outcomes in asphyxiated neonates receiving hypothermia therapy. Design, Setting, and Participants: This prespecified nested cohort study of infants enrolled in the Optimizing Cooling (OC) multicenter Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Neonatal Research Network trial from December 2011 to December 2013 with 2 years' follow-up randomized infants to either 72 hours of cooling (group A) or 120 hours (group B). The main trial included 364 infants. Of these, 194 were screened, 10 declined consent, and 120 met all predefined inclusion criteria. A total of 112 (90%) had complete data for death or disability. Data were analyzed from January 2018 to January 2020. Interventions: Serial amplitude electroencephalography recordings were compared in the 12 hours prior and 12 hours during rewarming for evidence of electrographic seizure activity by 2 central amplitude-integrated electroencephalography readers blinded to treatment arm and rewarming epoch. Odds ratios and 95% CIs were evaluated following adjustment for center, prior seizures, depth of cooling, and encephalopathy severity. Main Outcomes and Measures: The primary outcome was the occurrence of electrographic seizures during rewarming initiated at 72 or 120 hours compared with the preceding 12-hour epoch. Secondary outcomes included death or moderate or severe disability at age 18 to 22 months. The hypothesis was that seizures during rewarming were associated with higher odds of abnormal neurodevelopmental outcomes. Results: A total of 120 newborns (70 male [58%]) were enrolled (66 in group A and 54 in group B). The mean (SD) gestational age was 39 (1) weeks. There was excellent interrater agreement (κ, 0.99) in detection of seizures. More infants had electrographic seizures during the rewarming epoch compared with the preceding epoch (group A, 27% vs 14%; P = .001; group B, 21% vs 10%; P = .03). Adjusted odd ratios (95% CIs) for seizure frequency during rewarming were 2.7 (1.0-7.5) for group A and 3.2 (0.9-11.6) for group B. The composite death or moderate to severe disability outcome at 2 years was significantly higher in infants with electrographic seizures during rewarming (relative risk [95% CI], 1.7 [1.25-2.37]) after adjusting for baseline clinical encephalopathy and seizures as well as center. Conclusions and Relevance: Findings that higher odds of electrographic seizures during rewarming are associated with death or disability at 2 years highlight the necessity of electroencephalography monitoring during rewarming in infants at risk. Trial Registration: ClinicalTrials.gov Identifier: NCT01192776.
Asunto(s)
Hipotermia Inducida , Hipoxia-Isquemia Encefálica/complicaciones , Hipoxia-Isquemia Encefálica/terapia , Recalentamiento , Convulsiones/etiología , Asfixia Neonatal/complicaciones , Estudios de Casos y Controles , Electroencefalografía , Femenino , Humanos , Recién Nacido , MasculinoRESUMEN
OBJECTIVE: To determine mean arterial pressure values during the first 24 hours for "stable" and "unstable" extremely low birth weight (ELBW) infants and to ascertain its association with perinatal factors. BACKGROUND: In ELBW infants, hypotension is diagnosed by nonspecific clinical signs together with reference arterial pressure values extrapolated from regression models or from scarce actual observations. DESIGN: Retrospective cohort study. METHODS: 101 ELBW (< or = 600 g) infants born in our medical center (1989-2000). Considered stable were 36 infants with umbilical cord hemoglobin > or = 14 g/dl who, although mechanically ventilated, had normal acid-base balance, no patent ductus arteriosus, had not received indomethacin, steroids, muscle relaxants, narcotics, were never treated for hypotension and survived at least 7 days. The remaining 65 infants constituted the unstable group. Arterial pressures were determined by oscillometry (OBP) and direct transducer readings through an umbilical line (MAP). All admission and 10% of the readings were by OBP; the remaining 1877 measurements were by MAP. RESULTS: Stable and unstable infants were similar in birth weight, demographics, history of chorioamnionitis, antepartum steroids, low Apgar scores, administration of epinephrine during resuscitation, and sepsis. Stable infants were different from unstable in gestational age (27+/-2 vs 25+/-2 weeks' gestational age [w GA]), history of preterm labor, preeclampsia, and neonatal mortality (22 vs 68%). Admission OBP (30+/-7 vs 29+/-10 Torr) were similar and 1-hour MAP were different (30+/-6 vs 27+/-7 Torr) between both groups. MAP for stable infants was higher throughout the 24 hours. Greater differences were noted between 3 and 6 hours when 34 of 65 unstable infants were treated for hypotension. Mean MAP and 10 percentile values for stable infants at 1, 3, 6, 12, and 24 hours were 30 (22), 31 (24), 32 (25), 34 (24), and 35 (28) Torr, respectively. MAPs did not correlate with birth weight, but they were lower among 19 stable infants < or = 26 w GA than among 17 stable infants > or = 27 w GA. History of preeclampsia, antenatal steroids, intratracheal epinephrine and cord hemoglobin did not influence MAP. Low 1-minute Apgar score and intracranial hemorrhage were associated with low MAP during the first day. CONCLUSION: There is a wide variation of GA among ELBW infants. MAPs increase with GA and with postnatal age. Shortly after birth, arterial pressures are similar for stable and unstable infants. Failure to increase MAP between 3 and 6 hours of life should create concern. MAP < or = 28 Torr at 3 hours of life is a reasonable, but not absolute, predictor of the need for hypotension treatment.
Asunto(s)
Recién Nacido de muy Bajo Peso/fisiología , Puntaje de Apgar , Peso al Nacer , Determinación de la Presión Sanguínea , Estudios de Cohortes , Femenino , Edad Gestacional , Humanos , Hipotensión/diagnóstico , Recién Nacido , Masculino , Estudios RetrospectivosRESUMEN
BACKGROUND: Feeding difficulties and gastroesophageal reflux (GER) are common problems in neonates. The authors hypothesize that GER could be influenced by feeding mechanics by evaluating the effects of feeding volumes, feeding durations, feeding flow rates, and caloric density on the chemical composition and clearance of GER in dysphagic neonates. METHODS: Symptomatic dysphagic neonates (n = 35) underwent evaluation for suspected GER using pH-impedance methods. RESULTS: The proportions of acid and nonacid GER were different during the first, second, and third postprandial hours (P < .0001). Prolonged feeding duration was significantly associated with decreased total, nonacid GER and BCT (P < .03). Significant positive correlations (P < .05) were detected between feeding flow rate vs frequency of total, nonacid GER and BCT. Significant positive correlation (P = .002) was noted between feeding volume and BCT. BCT decreased with each hourly interval (analysis of variance [ANOVA] P < .05); however, ACT increased with each hourly interval (ANOVA P = .05). Comparison between BCT and ACT at each postprandial hour is remarkable for longer ACT during the second and third hours after the initiation of feed (P ≤ .001). No significant correlation was noted between the milk types (breast milk or formula) or caloric density with regard to the GER characteristics. Oral-fed infants had more GER events than gavage-fed infants. CONCLUSIONS: Prolonged feeding durations and slower flow rates are associated with decreased frequency of GER. Modification of feeding duration and flow rate can be a useful adjunct to ameliorate GER in dysphagic neonates.