Xavier Durrmeyer

Use of analgesic and sedative drugs in the NICU: integrating clinical trials and laboratory data.

Recent advances in neonatal intensive care include and are partly attributable to growing attention for comfort and pain control in the term and preterm infant requiring intensive care. Limitation of painful procedures is certainly possible, but most critically ill infants require unavoidable painful or stressful procedures such as intubation, mechanical ventilation, or catheterization. Many analgesics (opioids and nonsteroidal anti-inflammatory drugs) and sedatives (benzodiazepines and other anesthetic agents) are available but their use varies considerably among units. This review summarizes current experimental knowledge on the effects of sedative and analgesic drugs on brain development and reviews clinical evidence that speaks for or against the use of common analgesic and sedative drugs in the NICU but avoids any discussion of anesthesia during surgery. Risk/benefit ratios of intermittent boluses or continuous infusions for the commonly used sedative and analgesic agents are discussed in the light of clinical and experimental studies. The limitations of extrapolating experimental results from animals to humans must be considered while making practical recommendations based on the currently available evidence.

Identification of SPOCK2 as a susceptibility gene for bronchopulmonary dysplasia

RATIONALE Bronchopulmonary dysplasia is the most common chronic respiratory disease in premature infants. Genetic factors might contribute to bronchopulmonary dysplasia susceptibility. OBJECTIVES To identify genetic variants involved in bronchopulmonary dysplasia through a genome-wide association study. METHODS We prospectively evaluated 418 premature neonates (gestational age <28 wk), of whom 22% developed bronchopulmonary dysplasia. Two discovery series were created, using a DNA pooling strategy in neonates from white and African ancestry. Polymorphisms associated with the disease were confirmed in an independent replication population. Genes were then explored by fine mapping and associations were replicated in an external Finnish population of 213 neonates. Validated genes expression patterns were studied in rat lung, after air or hyperoxia exposure. MEASUREMENTS AND MAIN RESULTS SPOCK2 gene was identified by both discovery series. The most significant polymorphism (rs1245560; P = 1.66 × 10(-7)) was confirmed by individual genotyping, and in the replication population (P = 0.002). Fine mapping confirmed the association of rs1245560 with bronchopulmonary dysplasia in both white and African populations with adjusted odds ratios of 2.96 (95% confidence interval [CI], 1.37-6.40) and 4.87 (95% CI, 1.88-12.63), respectively. In white neonates, rs1049269 was also associated with the disease (odds ratio, 3.21; 95% CI, 1.51-6.82). These associations were replicated in the Finnish population. In newborn rat lungs, SPOCK2 mRNA levels markedly increased during the alveolar stage of lung development. After rat exposure to hyperoxia, SPOCK2 expression increased relative to air-exposed controls. CONCLUSIONS We identified SPOCK2 as a new possible candidate susceptibility gene for bronchopulmonary dysplasia. Its lung expression pattern points toward a potential role in alveolarization.

Pulmonary effects of keratinocyte growth factor in newborn rats exposed to hyperoxia.

Acute lung injury and compromised alveolar development characterize bronchopulmonary dysplasia (BPD) of the premature neonate. High levels of keratinocyte growth factor (KGF), a cell-cell mediator with pleiotrophic lung effects, are associated with low BPD risk. KGF decreases mortality in hyperoxia-exposed newborn rodents, a classic model of injury-induced impaired alveolarization, although the pulmonary mechanisms of this protection are poorly defined. These were explored through in vitro and in vivo approaches in the rat. Hyperoxia decreased by 30% the rate of wound closure of a monolayer of fetal alveolar epithelial cells, due to cell death, which was overcome by recombinant human KGF (100 ng/ml). In rat pups exposed to >95% O2 from birth, increased viability induced by intraperitoneal injection of KGF (2 microg/g body wt) every other day was associated with prevention of neutrophil influx in bronchoalveolar lavage (BAL), prevention of decreases in whole lung DNA content and cell proliferation rate, partial prevention of apoptosis increase, and a markedly increased proportion of surfactant protein B-immunoreactive cells in lung parenchyma. Increased lung antioxidant capacity is likely to be due in part to enhanced CAAT/enhancer binding protein alpha expression. By contrast, KGF neither corrected changes induced by hyperoxia in parameters of lung morphometry that clearly indicated impaired alveolarization nor had any significant effect on tissue or BAL surfactant phospholipids. These findings evidence KGF alveolar epithelial cell protection, enhancing effects on alveolar repair capacity, and anti-inflammatory effects in the injured neonatal lung that may account, at least in part, for its ability to reduce mortality. They argue in favor of a therapeutic potential of KGF in the injured neonatal lung.

Association Between Early Screening for Patent Ductus Arteriosus and In-Hospital Mortality Among Extremely Preterm Infants.

IMPORTANCE There is currently no consensus for the screening and treatment of patent ductus arteriosus (PDA) in extremely preterm infants. Less pharmacological closure and more supportive management have been observed without evidence to support these changes. OBJECTIVE To evaluate the association between early screening echocardiography for PDA and in-hospital mortality. DESIGN, SETTING, AND PARTICIPANTS Comparison of screened and not screened preterm infants enrolled in the EPIPAGE 2 national prospective population-based cohort study that included all preterm infants born at less than 29 weeks of gestation and hospitalized in 68 neonatal intensive care units in France from April through December 2011. Two main analyses were performed to adjust for potential selection bias, one using propensity score matching and one using neonatal unit preference for early screening echocardiography as an instrumental variable. EXPOSURES Early screening echocardiography before day 3 of life. MAIN OUTCOMES AND MEASURES The primary outcome was death between day 3 and discharge. The secondary outcomes were major neonatal morbidities (pulmonary hemorrhage, severe bronchopulmonary dysplasia, severe cerebral lesions, and necrotizing enterocolitis). RESULTS Among the 1513 preterm infants with data available to determine exposure, 847 were screened for PDA and 666 were not; 605 infants from each group could be paired. Exposed infants were treated for PDA more frequently during their hospitalization than nonexposed infants (55.1% vs 43.1%; odds ratio [OR], 1.62 [95% CI, 1.31 to 2.00]; absolute risk reduction [ARR] in events per 100 infants, -12.0 [95% CI, -17.3 to -6.7). Exposed infants had a lower hospital death rate (14.2% vs 18.5% ; OR, 0.73 [95% CI, 0.54 to 0.98]; ARR, 4.3 [95% CI, 0.3 to 8.3]) and a lower rate of pulmonary hemorrhage (5.6% vs 8.9%; OR, 0.60 [95% CI, 0.38 to 0.95]; ARR, 3.3 [95% CI, 0.4 to 6.3]). No differences in rates of necrotizing enterocolitis, severe bronchopulmonary dysplasia, or severe cerebral lesions were observed. In the overall cohort, instrumental variable analysis yielded an adjusted OR for in-hospital mortality of 0.62 [95% CI, 0.37 to 1.04]. CONCLUSIONS AND RELEVANCE In this national population-based cohort of extremely preterm infants, screening echocardiography before day 3 of life was associated with lower in-hospital mortality and likelihood of pulmonary hemorrhage but not with differences in necrotizing enterocolitis, severe bronchopulmonary dysplasia, or severe cerebral lesions. However, results of the instrumental variable analysis leave some ambiguity in the interpretation, and longer-term evaluation is needed to provide clarity.

Are Cytochrome P450 CYP2C8 and CYP2C9 Polymorphisms Associated with Ibuprofen Response in Very Preterm Infants

Background Patent ductus arteriosus (PDA) in extremely preterm infants remains a challenging condition with conflicting treatment strategies. Ibuprofen is currently used to treat PDA with ductal closure failure rate up to 40%. We test the hypothesis that cytochrome P450 CYP2C8/2C9 polymorphisms may predict ibuprofen response. Methodology/Principal Findings We studied extremely preterm neonates with haemodynamically significant PDA and treated with ibuprofen. One or two variant CYP2C8 and/or 2C9 alleles were found in 17% of the population, most of them were from Caucasian ethnicity (67–74%). Response to ibuprofen and clinical course of infants carrying variants CYP2C8 and CYP2C9 were similar. Comparing infants with wild type or variant CYP2C8 and CYP2C9 genotypes, response rate to ibuprofen was significantly higher in wild type than in mutated carriers in univariate analysis (73% versus 52%, p = 0.04). Comparing responders (ductus closure; n = 75) and non-responders (surgical ligation; n = 36), the only two factors significantly associated with the response to ibuprofen using multivariate analysis were higher gestational age and non Caucasian ethnicity but not CYP2C polymorphism. Conclusions CYP2C polymorphism was not associated with PDA response to ibuprofen and this factor appears not appropriate to optimize the ductal closure rate by modulating ibuprofen dosing strategy. This study points out the role for ethnicity in the interindividual variability of response to ibuprofen in extremely preterm infants.

Premedication for neonatal endotracheal intubation: results from the epidemiology of procedural pain in neonates study.

Objectives: To describe the frequency and nature of premedications used prior to neonatal endotracheal intubation; to confront observed practice with current recommendations; and to identify risk factors for the absence of premedication. Design, Setting, and Patients: Data concerning intubations were collected prospectively at the bedside as part of an observational study collecting around-the-clock data on all painful or stressful procedures performed in neonates during the first 14 days of their admission to 13 tertiary care units in the region of Paris, France, between 2005 and 2006. Intervention: Observational study. Measurements and Main Results: Specific premedication prior to endotracheal intubation was assessed. Ninety one intubations carried out on the same number of patients were analyzed. The specific premedicationrate was 56% and included mostly opioids (67%) and midazolam (53%). Compared with recent guidance from the American Academy of Pediatrics, used premedications could be classified as “preferred” (12%), “acceptable” (18%), “not recommended” (27%), and “not described” (43%). In univariate analysis, infants without a specific premedication compared with others were younger at the time of intubation (median age: 0.7 vs. 2.0 days), displayed significantly more frequent spontaneous breathing at the time of intubation (31% vs. 12%) and a higher percentage of analgesia for all other painful procedures (median values: 16% vs. 6%). In multivariate analysis, no factor remained statistically significant. Conclusions: Premedication use prior to neonatal intubation was not systematically used and when used it was most frequently inconsistent with recent recommendations. No patient- or center-related independent risk factor for the absence of premedication was identified in this study.

Impact of Common Treatments Given in the Perinatal Period on the Developing Brain

Background: Over the last decades, considerable progress has been made in the perinatal management of high-risk preterm neonates, changing the landscape of pathological conditions associated with neurological impairments. Major focal destructive lesions are now less common, and the predominant neuropathological lesion is diffuse white-matter damage in the most immature infants. Similarly, over the last few years, we have observed a trend towards a decrease in neurological impairment in the absence of treatments specifically aimed at neuroprotection. Objectives: We examined whether recent changes in treatment strategies in perinatal care during the perinatal period could have had an indirect beneficial impact on the occurrence of brain lesions and their consequences. Methods: Thus, we reviewed the effects of the most common treatments administered during the perinatal period to the mother or to very preterm infants on brain damage and neurocognitive follow-up. Results: Antenatal steroids and exogenous surfactant are the two main treatments capable of leading to neuroprotection in very preterm infants. Randomized controlled trials are currently investigating the effects of inhaled nitric oxide and erythropoietin, while antenatal magnesium sulphate and caffeine are also likely to provide some neuroprotection, but this needs to be further investigated. Finally, other common treatments against pain, haemodynamic failure and patent ductus arteriosus have conflicting or no effects on the developing brain. Conclusion: While specific neuroprotective drugs are still awaited, recent advances in perinatal care have been associated with an unexpected but significant decrease in the incidence of both severe brain lesions and neurological impairment.

Epidemiology and neonatal pain management of heelsticks in intensive care units: EPIPPAIN 2, a prospective observational study

BACKGROUND Heelstick is the most frequently performed skin-breaking procedure in the neonatal intensive care units (NICUs). There are no large multicenter studies describing the frequency and analgesic approaches used for heelsticks performed in NICUs. OBJECTIVES To describe the frequency of heelsticks and their analgesic management in newborns in the NICU. To determine the factors associated with the lack of specific preprocedural analgesia for this procedure. DESIGN EPIPPAIN 2 (Epidemiology of Procedural PAin In Neonates) is a descriptive prospective epidemiologic study. SETTING All 16 NICUs in the Paris region in France. PARTICIPANTS All newborns in the NICU with a maximum corrected age of 44 weeks +6 days of gestation on admission who had at least one heelstick during the study period were eligible for the study. The study included 562 newborns. METHODS Data on all heelsticks and their corresponding analgesic therapies were prospectively collected. The inclusion period lasted six weeks, from June 2, 2011 to July 12, 2011. Newborns were followed from their admission to the 14th day of their NICU stay or discharge, whichever occurred first. RESULTS The mean (SD) gestational age was 33.3 (4.4) weeks and duration of participation was 7.5 (4.4) days. The mean (SD; range) of heelsticks per neonate was 16.0 (14.4; 1-86) during the study period. Of the 8995 heelsticks studied, 2379 (26.4%) were performed with continuous analgesia, 5236 (58.2%) with specific preprocedural analgesia. Overall, 6764 (75.2%) heelsticks were performed with analgesia (continuous and/or specific). In a multivariate model, the increased lack of preprocedural analgesia was associated with female sex, term birth, high illness severity, tracheal or noninvasive ventilation, parental absence and use of continuous sedation/analgesia. CONCLUSIONS Heelstick was very frequently performed in NICUs. Although, most heelsticks were performed with analgesia, this was not systematic. The high frequency of this procedure and the known adverse effects of repetitive pain in neonates should encourage the search of safe and effective strategies to reduce their number.

Two-year outcomes of a randomized controlled trial of inhaled nitric oxide in premature infants.

BACKGROUND AND OBJECTIVES The European Union Nitric Oxide trial was designed to assess the potential benefits of inhaled nitric oxide (iNO) compared with placebo in infants with respiratory failure. This follow-up study evaluated respiratory, neurodevelopmental, and other outcomes for infants entered into the European Union Nitric Oxide trial to age 2 years. METHODS: In a multicenter, randomized, double-blind study, preterm infants born at <29 weeks’ gestation with moderate respiratory failure were allocated to receive iNO (5 ppm) or placebo for 7 to 21 days. Subjects underwent assessments at 1 and 2 years corrected for prematurity. RESULTS: At 36 weeks’ postmenstrual age, 696 of 792 infants were alive; 4 in the iNO arm subsequently died before age 2 years compared with 7 in the control arm. We evaluated 95% of the survivors at 12 months and 90% at 2 years. In the iNO arm, 244 of 363 (67.2%) infants had survived without disability at age 2 years compared with 270 of 374 (72.2%) who received placebo (P = .094). Mean (SD) cognitive composite scores (Bayley Scales of Infant and Toddler Development, third edition) were 94 (13) in the iNO group and 95 (14) in the placebo group; in the iNO group, 19% scored <85 and 9.5% developed cerebral palsy compared with 13.3% and 9%, respectively. There were no significant differences in hospitalizations overall or due to respiratory illness in use of home oxygen therapy or respiratory medications, in growth, or in other health outcomes. CONCLUSIONS: At 2 years of age, low-dose (5 ppm) iNO started early (<24 hours after birth) for a median of 20 days did not affect neurodevelopmental or other health outcomes.

Delivery room deaths of extremely preterm babies: an observational study

Objective Many extremely preterm neonates die in the delivery room (DR) after decisions to withhold or withdraw life-sustaining treatments or after failed resuscitation. Specific palliative care is then recommended but sparse data exist about the actual management of these dying babies. The objective of this study was to describe the clinical course and management of neonates born between 22 and 26 weeks of gestation who died in the DR in France. Design, setting, patients Prospective study including neonates, who were liveborn between 22+0 and 26+6 weeks of gestation and died in the DR in 2011, among infants included in the EPIPAGE-2 study at the 18 centres participating in this substudy of extremely preterm neonates. Data were collected by a questionnaire completed by the professional caring for each baby. Results The study included 73 children, with a median (IQR) gestational age of 24 (23–24) weeks. Median (IQR) duration of life was 53 (20–82) min. All but one were both wrapped and warmed. Pain was assessed for 72%, although without using any scale. Gasping was described for 66%. Comfort medications were administered to 35 children (50%), significantly more frequently to babies with gasping (p=0.001). Mother–child contact was reported for 78%, and psychological support offered to parents of 92%. Conclusions Non-pharmacological comfort care and parental support were routinely given. Comfort medication was given much more frequently than previously reported in other DRs. These data should encourage work on the indications for comfort medication and the interpretation of gasping.