Thierry Debillon

Fetal lung volume in congenital diaphragmatic hernia

In a retrospective study of 22 neonates with congenital diaphragmatic hernia, fetal lung volume (FLV) measured by magnetic resonance imaging was associated with survival; the best FLV ratio cut-off to predict mortality was 30% of expected FLV. This study supports a correlation between FLV and the chances of survival.

Oxygen cost of breathing in newborn infants with long-term ventilatory support

Oxygen consumption (VO2) was measured during controlled and spontaneous ventilation with continuous positive airway pressure in newborn infants in whom chronic lung disease later developed. The oxygen cost of breathing (the difference in VO2 between spontaneous and controlled ventilation) was significantly higher in infants with chronic lung disease than in control infants (20.1% +/- 7.5% and 4.8% +/- 4.9% of VO2 during spontaneous ventilation (p < 0.05), respectively).

Calibration of respiratory inductance plethysmograph in preterm infants with different respiratory conditions

Respiratory inductance plethysmography (RIP) is a method for respiratory measurements particularly attractive in infants because it is noninvasive and it does not interfere with the airway. RIP calibration remains controversial in neonates, and is particularly difficult in infants with thoraco-abdominal asynchrony or with ventilatory assist. The objective of this study was to evaluate a new RIP calibration method in preterm infants either without respiratory disease, with thoraco-abdominal asynchrony, or with ventilatory support. This method is based on (i) a specifically adapted RIP jacket, (ii) the least squares method to estimate the volume/motion ribcage and abdominal coefficients, and (iii) an individualized filtering method that takes into account individual breathing pattern. The reference flow was recorded with a pneumotachograph. The accuracy of flow reconstruction using the new method was compared to the accuracy of three other calibration methods, with arbitrary fixed RIP coefficients or with coefficients determined according to qualitative diagnostic calibration method principle. Fifteen preterm neonates have been studied; gestational age was (mean +/- SD) 31.7 +/- 0.8 weeks; birth weight was 1,470 +/- 250 g. The respiratory flow determined with the new method had a goodness of fit at least equivalent to the other three methods in the entire group. Moreover, in unfavorable conditions--breathing asynchrony or ventilatory assist--the quality of fit was significantly higher than with the three other methods (P < 0.05, repeated measures ANOVA). Accuracy of tidal volume measurements was at least equivalent to the other methods, and the breath-by-breath differences with reference volumes were lower, although not significantly, than with the other methods. The goodness of fit of the reconstructed RIP flow with this new method--even in unfavorable respiratory conditions--provides a prerequisite for the study of flow pattern during the neonatal period.

Leading causes of preterm delivery as risk factors for intraventricular hemorrhage in very preterm infants: results of the EPIPAGE 2 cohort study

BACKGROUND: Intraventricular hemorrhage is a major risk factor for neurodevelopmental disabilities in preterm infants. However, few studies have investigated how pregnancy complications responsible for preterm delivery are related to intraventricular hemorrhage. OBJECTIVE: We sought to investigate the association between the main causes of preterm delivery and intraventricular hemorrhage in very preterm infants born in France during 2011 between 22‐31 weeks of gestation. STUDY DESIGN: The study included 3495 preterm infants from the national EPIPAGE 2 cohort study who were admitted to neonatal intensive care units and had at least 1 cranial ultrasound assessment. The primary outcome was grade I‐IV intraventricular hemorrhage according to the Papile classification. Multinomial logistic regression models were used to study the relationship between risk of intraventricular hemorrhage and the leading causes of preterm delivery: vascular placental diseases, isolated intrauterine growth retardation, placental abruption, preterm labor, and premature rupture of membranes, with or without associated maternal inflammatory syndrome. RESULTS: The overall frequency of grade IV, III, II, and I intraventricular hemorrhage was 3.8% (95% confidence interval, 3.2–4.5), 3.3% (95% confidence interval, 2.7–3.9), 12.1% (95% confidence interval, 11.0–13.3), and 17.0% (95% confidence interval, 15.7–18.4), respectively. After adjustment for gestational age, antenatal magnesium sulfate therapy, level of care in the maternity unit, antenatal corticosteroids, and chest compressions, infants born after placental abruption had a higher risk of grade IV and III intraventricular hemorrhage compared to those born under placental vascular disease conditions, with adjusted odds ratios of 4.3 (95% confidence interval, 1.1–17.0) and 4.4 (95% confidence interval, 1.1–17.6), respectively. Similarly, preterm labor with concurrent inflammatory syndrome was associated with an increased risk of grade IV intraventricular hemorrhage (adjusted odds ratio, 3.4; 95% confidence interval, 1.1–10.2]). Premature rupture of membranes did not significantly increase the risk. CONCLUSION: Relationships between the causes of preterm birth and intraventricular hemorrhage were limited to specific and rare cases involving acute hypoxia‐ischemia and/or inflammation. While the emergent nature of placental abruption would challenge any attempts to optimize management, the prenatal care offered during preterm labor could be improved.

Secondary adrenal insufficiency in the acute phase of pediatric traumatic brain injury

PurposeA high incidence of secondary adrenal insufficiency (AI) has been reported several months after a traumatic brain injury (TBI) in pediatric patients. Data from studies in adults suggest that AI may occur during the acute phase of TBI, with potential negative effects in the management of these vulnerable patients. The aim of this study was to describe the prevalence and the characteristics of AI in the acute phase of pediatric TBI.MethodsAdrenal function was systematically evaluated in patients admitted to the pediatric intensive care unit following a TBI. Serial measurements of cortisol (9 samples) and adrenocorticotropic hormone (ACTH) were drawn from the second morning to the third morning post admission. Secondary AI was defined as all cortisols <200xa0nmol/l (6xa0μg/dl) with ACTH <12xa0pmol/l.ResultsTwenty-eight patients (2–15xa0years old) were evaluated. Secondary AI occurred in ten (36%) patients. AI was more frequent in patients with intracranial hypertension (pxa0<xa00.05). Patients with AI required longer mechanical ventilation (pxa0<xa00.05), and a non-significant trend for a higher Pediatric Logistic Organ Dysfunction score (pxa0=xa00.09) and greater norepinephrine dose (pxa0=xa00.11) was observed.ConclusionsSecondary AI is frequent during the acute phase of pediatric TBI, particularly when intracranial hypertension is present. Systematic assessment of pituitary function after TBI appears to be essential. A randomized clinical trial is warranted to evaluate the benefits of hormonal replacement therapy in TBI patients with AI.

Variability of end-expiratory lung volume in premature infants.

Background: Analysis of breath-to-breath variability of respiratory characteristics provides information on the respiratory control. In infants, the control of end-expiratory lung volume (EELV) is active and complex, and it can be altered by respiratory disease. The pattern of EELV variability may reflect the behavior of this regulatory system. Objectives: We aimed to characterize EELV variability in premature infants, and to evaluate variability pattern changes associated with respiratory distress and ventilatory support. Methods: EELV variations were recorded using inductance plethysmography in 18 infants (gestational age 30–33 weeks) during the first 10 days of life. An autocorrelation analysis was conducted to evaluate the ‘EELV memory’, i.e. the impact of the characteristics of one breath on the following breaths. Results: In infants without respiratory symptoms, EELV variability was high, with large standard deviations of EELV. Autocorrelation was found to be significant until a median lag of 7 (interquartiles: 4–8) breaths. Autocorrelation was markedly prolonged in patients with respiratory distress or ventilatory support, with a higher number of breath lags with significant autocorrelation (p < 0.01) and higher autocorrelation coefficients (p < 0.05). Conventional assisted ventilation does not re-establish a healthy EELV profile and is associated with lower respiratory variability. Conclusions: In premature infants, EELV variability pattern is modified by respiratory distress with a prolonged ‘EELV memory’, which suggests a greater instability of the control of EELV.

Impact of Latency Duration on the Prognosis of Preterm Infants after Preterm Premature Rupture of Membranes at 24 to 32 Weeks' Gestation: A National Population-Based Cohort Study

Objective To assess the impact of latency duration on survival, survival without severe morbidity, and early‐onset sepsis in infants born after preterm premature rupture of membranes (PPROM) at 24‐32 weeks gestation. Study design This study was based on the prospective national population‐based Etude Épidémiologique sur les Petits Âges Gestationnels 2 cohort of preterm births and included 702 singletons delivered in France after PPROM at 24‐32 weeks gestation. Latency duration was defined as the time from spontaneous rupture of membranes to delivery, divided into 4 periods (12 hours to 2 days [reference], 3‐7 days, 8‐14 days, and >14 days). Multivariable logistic regression was used to assess the relationship between latency duration and survival, survival without severe morbidity at discharge, or early‐onset sepsis. Results Latency duration ranged from 12 hours to 2 days (18%), 3‐7 days (38%), 8‐14 days (24%), and >14 days (20%). Rates of survival, survival without severe morbidity, and early‐onset sepsis were 93.5% (95% CI 91.8‐94.8), 85.4% (82.4‐87.9), and 3.4% (2.0‐5.7), respectively. A crude association found between prolonged latency duration and improved survival disappeared on adjusting for gestational age at birth (aOR 1.0 [reference], 1.6 [95% CI 0.8‐3.2], 1.2 [0.5‐2.9], and 1.0 [0.3‐3.2] for latency durations from 12 hours to 2 days, 3‐7 days, 8‐14 days, and >14 days, respectively). Prolonged latency duration was not associated with survival without severe morbidity or early‐onset sepsis. Conclusion For a given gestational age at birth, prolonged latency duration after PPROM does not worsen neonatal prognosis.

Sound levels in a neonatal intensive care unit significantly exceeded recommendations, especially inside incubators

This study measured sound levels in a 2008 built French neonatal intensive care unit (NICU) and compared them to the 2007 American Academy of Pediatrics (AAP) recommendations. The ultimate aim was to identify factors that could influence noise levels.

Faut-il réaliser une sédation analgésie du nouveau-né pour l’intubation en salle de naissance ? « Le contre »

Depuis vingt ans, l’analgesie du nouveau-ne est devenue une preoccupation majeure des soignants en neonatologie. Des moyens fiables existent pour reconnaitre la douleur aigue ou prolongee et de nombreux travaux permettent de guider les neonatologues pour la prescription de medicaments antalgiques ou sedatifs. Limiter la douleur aigue lors des gestes techniques est necessaire, en particulier lors de l’intubation. Mais l’intubation en salle de naissance constitue une situation particuliere pour le nouveau-ne, conduisant a s’interroger sur la pertinence de l’administration d’antalgiques ou de sedatifs. En salle de naissance, l’enfant est en pleine phase d’adaptation a la vie extra-uterine avec parfois une grande instabilite physiologique, qui ne doit pas etre aggravee par les effets secondaires de ces medicaments. La prise en charge du syndrome de detresse respiratoire du nouveau-ne, pour lequel l’enfant est le plus souvent intube, comporte maintenant une extubation rapide, qui ne doit pas etre genee par l’effet depresseur respiratoire des antalgiques. Enfin, aucune recommandation precise et fondee sur un solide niveau de preuve n’existe pour cette situation particuliere. Elle ne peut donc etre abordee en respectant les exigences de l’Evidence Based Medicine. Tous ces arguments sont developpes dans ce chapitre, conduisant a ne pas recommander l’utilisation de ces medicaments pour l’intubation urgente en salle de naissance. En dehors de l’urgence vitale, le clinicien doit plutot s’orienter vers un transfert de l’enfant en neonatologie, afin d’effectuer une intubation reglee et differee en service de soins, qui pourra etre encadree d’une prescription d’antalgiques ou de sedatifs.

La sensorialité tactile du grand prématuré

Des etudes recentes montrent que les nouveau-nes a terme sont capables de discriminer des objets de poids, de forme ou de texture differentes en les explorant avec leur main. Ils sont egalement capables de transferer des informations concernant la forme ou la texture d’un objet d’une main a l’autre, ainsi que de reconnaitre visuellement la forme et la texture d’un objet prealablement explore tactilement (transfert intermodal d’information).