Respiratory Morbidity In Infants Research Articles

PRECeDe Pilot: Prevention of neonatal respiratory distress with antenatal corticosteroids before elective caesarean section in women with diabetes - a feasibility randomised trial.

The PRECeDe Pilot Trial was designed to determine the feasibility of undertaking a multicentre, randomised controlled trial (RCT) to assess the efficacy of antenatal corticosteroids administration within 7 days before elective caesarean section (CS) in women with pre-gestational diabetes (PGDM) or gestational diabetes (GDM). Triple blind, parallel group, placebo-controlled, pilot RCT. Single-centre tertiary maternity hospital in Melbourne, Australia. Pregnant women with PGDM (type 1 or type 2 diabetes) or GDM booked for a planned CS scheduled between 35+0 and 38+6 weeks of gestation. Eligible participants were randomised to receive two injections of either betamethasone 11.4 mg or normal saline placebo, 24 hours apart within 7 days before CS scheduled between 35+0 and 38+6 weeks of gestation. The proportion of eligible women who consented and were randomised. Australian and New Zealand Clinical Trials Registry ACTRN12619001475134. Of 537 women eligible, 182 were approached and 47 (26%) were recruited. Of these, 22 were allocated to the betamethasone group and 25 were allocated to the placebo group. There were no serious adverse events related to participation. It is feasible to undertake a triple-blind, placebo-controlled RCT investigating the efficacy of antenatal corticosteroids in preventing respiratory morbidity in infants of women with PGDM or GDM who are undergoing an elective CS between 35+0 and 38+6 weeks.

Burden of Treatments for Respiratory Complications in Extremely Premature Infants: Interviews with Caregivers

Introduction: Extremely premature (EP) infants (<28 weeks gestational age) with respiratory conditions after discharge from the neonatal intensive care unit (NICU) impose a significant burden on caregivers. This study explored caregiver burden post-NICU discharge and perceptions of meaningful change in infant chronic respiratory morbidity. Methods: Adult primary caregivers of EP infants 3–14 months corrected age were recruited through patient advocacy organizations or hospital centers in the USA, Northern Ireland, Germany, and Japan and interviewed by phone. Interviews explored caregiver experiences with infants with respiratory conditions, associated treatment burden, and meaningful change in infant respiratory morbidity as measured by treatment use. Qualitative analysis of interview data was performed using MAXQDA software. Sociodemographic data were summarized using descriptive statistics. Results: Forty-five caregivers (95.6% female) of EP infants were interviewed. Respiratory morbidities post-NICU discharge included coughing (78%), breathing difficulties (76%), wheezing (58%), and bronchopulmonary dysplasia/chronic lung disease of prematurity (56%). Respiratory medications were required by 87% of infants, 80% used home respiratory technology support (e.g., supplemental oxygen), 38% were re-hospitalized, and 33% had emergency department visits. Caregivers considered visits to the emergency department to be the most burdensome treatment requirement they experienced, and reduction in the number of emergency department visits was considered the most meaningful change in treatment use. Conclusion: These findings underscore the significant burden faced by caregivers of EP infants with respiratory morbidities. Development of treatments for respiratory complications should take into consideration the concerns and preferences of caregivers in order to provide a meaningful benefit.

Colonization of the newborn respiratory tract and its association with respiratory morbidity in the first 6 months of life: A prospective cohort study

ObjectivesWe aimed to determine the association between newborn bacterial colonization and infant respiratory morbidity in the first 6 months of life. MethodsThis prospective study included healthy newborn infants. Nasopharyngeal swabs performed within 72 hours of delivery were analyzed using polymerase chain reaction. We assessed cumulative respiratory morbidity of infants at 6 months. ResultsA total of 426 mother-infant pairs were recruited. In 53.3% (n = 225) of newborns, Streptococcus pneumoniae (46%) and Staphylococcus aureus (7.3%) were isolated. None had Haemophilus influenzae nor Moraxella catarrhalis. At the age of 6 months, 50.7% of infants had experienced respiratory symptoms, 25% had unscheduled doctor visits, and 10% were treated with nebulizers. Colonization with S. pneumoniae was associated with reduced risk of any respiratory symptom (adjusted odds ratio [aOR] 0.39, 95% confidence interval [CI] 0.16, 0.50), unscheduled doctor visits (aOR 0.35; 95% CI 0.18, 0.67), and nebulizer treatment (aOR 0.23, 95% CI 0.07, 0.72) at 6 months. Pregnancy-induced hypertension was also associated with increased need for nebulizer treatment (aOR 9.11, 95% CI 1.43, 58.1). ConclusionColonization of the newborn respiratory tract occurred in 53% of infants. S. pneumoniae was the most common organism, and this was associated with a reduced risk for respiratory morbidity at 6 months of life.

The impact of the Antenatal Late Preterm Steroids trial on the administration of antenatal corticosteroids

In 2016 the Antenatal Late Preterm Steroids study was published, demonstrating that antenatal corticosteroid therapy given to women at risk of late preterm delivery reduces respiratory morbidity in infants. However, the administration of antenatal corticosteroid therapy in late-preterm infants remains controversial. Late-preterm infants do not suffer from the same rates of morbidity as early-preterm infants, and the short-term benefits of antenatal corticosteroid therapy are less pronounced; consequently, the risk of possible harm is more difficult to balance. This study aimed to evaluate the association between the publication of the Antenatal Late Preterm Steroids study or the subsequent changes in guidelines and the rates of antenatal corticosteroid therapy administration in late-preterm infants in the United States. Data analyzed were publicly available US birth certificate data from January 1, 2016 to December 31, 2018. An interrupted time series design was used to analyze the association between publication of the Antenatal Late Preterm Steroids study and changes in monthly rates of antenatal corticosteroid administration in late preterm gestation (34+0 to 36+6 weeks). Births at 28+0 to 31+6 weeks' gestation were used as a control. Antenatal corticosteroid therapy administration in women with births at 32+0 to 34+6 weeks was explored to analyze whether the intervention influenced antenatal corticosteroid therapy administration in women in the subgroup approaching 34 weeks' gestation. Antenatal corticosteroid therapy administration in women with term births (>37 weeks' gestation) was analyzed to explore if the intervention influenced the number of term babies exposed to antenatal corticosteroid therapy. Our regression model allowed analysis of both step and slope changes. February 2016 was chosen as the intervention period. Our sample size was 18,031,950 total births. Of these, 1,056,047 were births at 34+0 to 36+6 weeks' gestation, 123,788 at 28+0 to 31+6 weeks, 153,708 at 32 to 33 weeks, and 16,602,699 were term births. There were 95,708 births at <28 weeks' gestation. There was a statistically significant increase in antenatal corticosteroid therapy administration rates in late preterm births following the online publication of the Antenatal Late Preterm Steroids study (adjusted incidence rate ratio, 1.48; 95% confidence interval, 1.36-1.61; P=.00). A significant increase in antenatal corticosteroid therapy administration rates was also seen in full-term births following the online publication of the Antenatal Late Preterm Steroids study. No significant changes were seen in antenatal corticosteroid administration rates in gestational age groups of 32+0 to 33+6 weeks or 28+0 to 31+6 weeks. Online publication of the Antenatal Late Preterm Steroids study was associated with an immediate and sustained increase in the rates of antenatal corticosteroid therapy administration in late preterm births across the United States, demonstrating a swift and successful implementation of the Antenatal Late Preterm Steroids study guidance into clinical practice. However, there is an unnecessary increase in full-term infants receiving antenatal corticosteroid therapy. Given that the long-term consequences of antenatal corticosteroid therapy are yet to be elucidated, efforts should be made to minimize the number of infants unnecessarily exposed to antenatal corticosteroid therapy.

Maternal diet during pregnancy and infant respiratory morbidity: A prospective study.

Maternal diet during pregnancy may impact infant respiratory morbidity. The aim was to determine the association between antenatal maternal diet and respiratory morbidity of their infants during their first 6 months of life. This prospective cohort study included healthy motherinfant pairs. Maternal diet during the last trimester was determined with a validated food frequency questionnaire. Infant respiratory morbidity was solicited at 1, 3 and 6 months. Three hundred mother-baby pairs were recruited. Maternal consumption of milk and dairy products was associated with reduced respiratory symptoms at 1 month (aOR 0.29 [95% CI: 0.10, 0.86], p=0.03) and 3 months old (aOR 0.43 [95% CI: 0.20, 0.93], p=0.03), while intake of confectionery items was associated with increased unscheduled doctor visits at 3 months (aOR 2.01 [95% CI 1.33, 3.06], p=0.001) and increased nebuliser treatment at both 3 months (aOR 1.88 [95% CI 1.12, 3.17], p=0.02) and 6 months (aOR 1.64 [95% CI 1.05, 2.54], p=0.03). Finally, at 6 months, hypertensive disorders during pregnancy was associated with increased nebuliser treatment (aOR 17.3 [95% CI 1.50, 199], p=0.02) while exclusive breastfeeding was associated with reduced incidence of respiratory symptoms (OR 0.47 [95% CI 0.26, 0.83], p=0.01). Increased antenatal maternal consumption of milk and dairy products may reduce respiratory morbidity while increased consumption of confectionery items may increase respiratory morbidity in their infants during the first 6 months of life.

Neonatal FeNO, risk factors, and respiratory morbidity in infants: A cohort study.

Respiratory symptoms in infancy are more common in premature infants. Nitric oxide (NO) is involved in prenatal and neonatal lung development. Measurement of exhaled NO is easy and well-tolerated by neonates. We investigated whether neonatal exhaled NO can be used to predict subsequent respiratory symptoms. Furthermore, we sought to determine prenatal and postnatal factors associated with increased respiratory symptom risk during the first year of life in premature and mature infants. Tidal fractional exhaled NO (FeNO) was measured in a birth cohort (n = 135) of premature and mature infants, up to six times during the first month of life. Primary outcomes were troublesome respiratory symptoms (TRS) and doctor-diagnosed asthmatic bronchitis (AB) at 1 year of age. The correlation between FeNO and TRS changed significantly in an age-dependent pattern in moderately premature infants (p = .02). Moderately premature infants with a low FeNO of 2 ppb on postnatal Day 3 had a 48% (95% confidence interval [CI]: 17%-80%) probability of TRS, compared with a probability of 12% (95% CI: 1%-64%) for otherwise similar infants with a FeNO of 11 ppb. Respiratory syncytial virus infection and parental smoking significantly increased the TRS risk in premature infants. Parental asthma and maternal antibiotic use during pregnancy significantly increased the TRS risk in mature infants. An age-specific association between neonatal FeNO and respiratory symptoms was seen in moderately premature infants. TRS risk was associated with postnatal factors in premature and prenatal factors in mature infants.

Maternal pre-pregnancy weight and early life lower respiratory tract infections in a low-income urban minority birth cohort

The prevalence of maternal obesity has increased dramatically with adverse consequences on infant health. Prior studies have reported associations between maternal obesity and childhood wheeze, asthma as well as lower respiratory tract infections (LRTI). However, studies examining the association of obesity with early-life LRTIs in low-income urban minority populations are still lacking. This is a critical gap because both obesity and infant respiratory morbidity are more prevalent and severe in these communities. We examined mother‐child dyads from the Boston Birth Cohort (BBC) to define the longitudinal association of maternal pre‐pregnancy BMI and LRTI in infancy, defined as the presence of bronchiolitis, bronchitis, or pneumonia during the first year of life (< 12 months of age). A total of 2,790 mother‐child dyads were included in our analyses. Infants born to pre-pregnancy obese mothers (n = 688, 25%) had 1.43 increased odds (adjOR = 1.43, 95% CI 1.08–1.88, p = 0.012) of developing LRTI during the first year of life when compared with newborns born to normal-weight mothers after adjusting by relevant LRTI risk factors. Notably, infants born to overweight mothers (n = 808, 29%) followed a similar trend (adjOR = 1.31, 95% CI 1.00–1.72, p = 0.048). Our study demonstrated that maternal pre-pregnancy obesity is an independent risk factor for the development of LRTI during infancy in a low-income urban minority birth cohort.

Adenovector 26 encoded prefusion conformation stabilized RSV-F protein induces long-lasting Th1-biased immunity in neonatal mice

While RSV is a major cause of respiratory morbidity in infants, vaccine development is hindered by the immaturity and Th2-bias of the infant immune system and the legacy of enhanced respiratory disease (ERD) after RSV infection following immunization with formalin inactivated (FI)-RSV vaccine in earlier clinical trials. Preclinical studies have demonstrated that an adenoviral vector-based RSV F vaccine candidate (Ad26.RSV.FA2) induces Th1-biased protective immune responses, without signs of ERD upon subsequent RSV challenge. We here developed an Ad26 vector encoding the RSV F protein stabilized in its prefusion conformation (Ad26.RSV.preF). In adult mice, Ad26.RSV.preF induced superior, Th1-biased IgG2a-dominated humoral responses as compared to Ad26.RSV.FA2, while maintaining the strong Th1-biased cellular responses. Similar to adult mice, Ad26.RSV.preF induced robust and durable humoral immunity in neonatal mice, again characterized by IgG2a-dominated RSV F-binding antibodies, and high and stable virus-neutralizing titers. In addition, vaccine-elicited cellular immune responses were durable and characterized by IFN-γ-producing CD4+ and CD8+ T cells, with a profound Th1 bias. In contrast, immunization of neonatal mice with FI-RSV resulted in IgG1 RSV F-binding antibodies associated with a Th2 phenotype, no detectable virus-neutralizing antibodies, and a Th2-biased cellular response. These results are supportive for the clinical development of Ad26.RSV.preF for use in infants.

Azithromycin administered for acute bronchiolitis may have a protective effect on subsequent wheezing.

ABSTRACTObjectiveA significant proportion of the infants developed recurrent wheezing after an acute bronchiolitis (AB) event. Recent studies have demonstrated protection for recurrent wheeze and lower respiratory morbidity in infants treated with azithromycin during an acute respiratory wheezing. The aim of the present study was to test the hypothesis that administration of azithromycin during an AB event reduces subsequent wheezing and hospital re-admissions.MethodsThis is a secondary analysis of a randomized, double-blinded, placebo-controlled trial, including unpublished data of wheezing and hospitalizations during the initial 6 months following admission for acute viral bronchiolitis. The study was performed in a tertiary University hospital. Infants (<12 months of age) hospitalized with AB were randomized to receive either azithromycin or placebo, administered orally, for 7 days. Families were contacted by telephone at 3 and 6 months after the initial acute event and answered to a standardized questionnaire in order to identify recurrent wheezing and hospital readmissions.ResultsOne hundred and four patients were included (Azithromycin group, n= 50; placebo group, n=54). Considering the total of patients contacted 3 months after hospitalization (n=70), the recurrence rate of wheezing in the azithromycin group was significantly lower than in the placebo group (RR = 0.48; CI = 0.24-0.98; p = 0.038).ConclusionAzithromycin significantly reduces the risk of subsequent wheezing between 0 and 3 months after hospital admission due to acute bronchiolitis irrespective of the presence of respiratory syncytial virus.

531: Neonatal outcomes following administration of antenatal corticosteroids in the late preterm period

The objective of this study was to determine the incidence of neonatal respiratory morbidity in infants born at 34-36 weeks gestation since the implementation of late preterm corticosteroid administration. A retrospective cohort study was performed on patients who delivered between 1/1/2015 and 4/24/2018 at a single institution. The study group included women who received 2 doses of 12 mg IM betamethasone 24 hours apart between 34/0 and 36/6 weeks. A historical cohort consisted of patients who delivered between 34/0 and 36/6 who did not receive betamethasone. Primary outcomes included a composite of respiratory treatment (rates of neonates requiring respiratory support in first 72 hours after delivery including continuous positive airway pressure (CPAP) or nasal cannula for at least 2 hours, supplemental oxygen with fraction of inspired oxygen of at least 0.30 for at least 4 hours, mechanical ventilation) and the rates of neonatal hypoglycemia (<44 mg/dL). A total of 376 patients were included – 121 patients who received late preterm steroids and 255 patients who served as a historical control. Preliminary data demonstrates no statistically significant differences in maternal demographics. A statistically significant difference in birthweight was initially noted between the groups (p < 0.001) however when controlled for there was no difference (p = 0.206). Initially, there was no statistically significant difference between the groups of neonates requiring respiratory treatment in the first 72 hours (p = 0.069), however, results became statistically significant when birthweight was controlled (p = 0.045). Neonates within the betamethasone group had higher rates of hypoglycemia compared to the control group (p = 0.012). The significance was retained even after controlling for the birthweight (p = 0.007). Administration of late preterm antenatal steroids was associated with lower rates of neonatal respiratory treatment. Exposed neonates had higher rates of hypoglycemia and need for supplemental treatment, in addition, the percentage observed were substantially higher than previous reports. Our results support past investigations.

Gender Differences in Respiratory Morbidity and Mortality of Preterm Neonates.

For the past century, researchers have underscored the “disadvantage” observed in respiratory morbidity and mortality of male newborns. In this contemporary review, we examine gender differences in preterm infant respiratory morbidity and mortality specifically appraising differences in the very low birth weight (VLBW) population as well as the late preterm (LPT) population. In the era of postnatal surfactant and antenatal corticosteroids, the gender gap in neonatal outcomes has not narrowed. Structural, physiologic, and hormonal sex differences may be at the root of this disparity. Further exploration into the origin of gender differences in respiratory morbidity and neonatal mortality will shape future therapies. These therapies may need to be gender specific to close the gender gap.

Effect of Prophylactic Corticosteroid Therapy on Respiratory Morbidity in Infants Borne at Term by Elective Cesarean Section at Omdurman Maternity Hospital

Objectives: A study done in Omdurman Maternity Hospital (OMH) during 2013, to study the effect of corticosteroid administration two days before an elective caesarean section to reduce the respiratory morbidity in infants born. Methodology: It is a randomized control trial study comparing prophylactic antenatal corticosteroids with no treatment given before elective caesarean section C/S. Results: A total of 560 patients of 5421 who underwent elective caesarean section C/S in 2013, were randomly selected, 281 (50.2%) were treated by 12 mg dexamethasone, two doses 12 hours apart, and 279 (49.8%) were in the control group. 26 infants were admitted to nursery there were 8 new-borns from the treatment group, and 18 from control group, with regards to indication of admission; those who had Respiratory distress (RDS) in the control group were 6 (2.2%),and in the treatment group were 2(0.7%), Transient tachypnea of the newborn( TTN) in the control group were 12 (4.3%), in the treatment group were 6(2.2%), (P value 0.00), (RR: 0.6 for TTN & 0.25 for RDS). Stay in special babies care unit (SBCU)<24 hours were 6 (2.2%) in control group and 8 (2.8%) in the treatment group, stay>24 hours were 12 (4.3%) in the control group and zero in the treatment, (P value was 0.026). 3 (1.1%) needed assisted ventilation, one death found in the control group (0.4%). Conclusion: Giving dexamethasone, two before elective C/S had a significant reduction in the respiratory morbidity and decrease hospital study. It has no adverse effect and can be safely used.

Rhinovirus Infections and Associated Respiratory Morbidity in Infants: A Prospective Cohort Study.

Risk factors promoting rhinovirus (RV) infections are inadequately described in healthy populations, especially infants. To determine the frequency of symptomatic and asymptomatic RV infections and identify possible risk factors from host and environment among otherwise healthy infants. In a prospective birth cohort, respiratory health was assessed in 41 term-born infants by weekly telephonic interviews during the first year of life, and weekly nasal swabs were collected to determine RV prevalence. In a multilevel logistic regression model, associations between prevalence and respiratory symptoms during RV infections and host/environmental factors were determined. Twenty-seven percent of nasal swabs in 41 infants tested positive for RVs. Risk factors for RV prevalence were autumn months [odds ratio (OR) = 1.71, P = 0.01, 95% confidence interval (CI): 1.13-2.61], outdoor temperatures between 5 and 10°C (OR = 2.33, P = 0.001, 95% CI: 1.41-3.86), older siblings (OR = 2.60, P = 0.001, 95% CI: 1.50-4.51) and childcare attendance (OR = 1.53, P = 0.07, 95% CI: 0.96-2.44). Fifty-one percent of RV-positive samples were asymptomatic. Respiratory symptoms during RV infections were less likely during the first 3 months of life (OR = 0.34, P = 0.003, 95% CI: 0.17-0.69) and in infants with atopic mothers (OR = 0.44, P = 0.008, 95% CI: 0.24-0.80). Increased tidal volume (OR = 1.67, P = 0.03, 95% CI: 1.04-2.68) and outdoor temperatures between 2 and 5°C (OR = 2.79, P = 0.02, 95% CI: 1.17-6.61) were associated with more symptoms. RVs are highly prevalent during the first year of life, and most infections are asymptomatic. Frequency of RV infections is associated with environmental factors, while respiratory symptoms during RV infections are linked to host determinants like infant age, maternal atopy or premorbid lung function.

Neonatal respiratory morbidity in late-preterm births in pregnancies with and without gestational diabetes mellitus

Objective: To evaluate neonatal respiratory morbidity in infants born late-preterm to mothers with or without gestational diabetes mellitus (GDM). Methods: Analysis of a population-based cohort of all live-born singletons, born at 34 0/7 to 36 6/7 weeks to mothers with and without GDM, focusing on transient tachypnea of the newborn (TTN) and respiratory distress syndrome (RDS).Results: The study group comprised 363 (4.7%) singletons born to mothers with GDM and the controls were 7400 born to mothers without GDM. Mothers with GDM were older (31.4 ± 5.1 versus 29.5 ± 5.1 years, p < 0.001) and were more likely to be hypertensive (OR 1.5, 95% CI 1.1–2.1). Neonates of GDM mothers were heavier at birth (2769 ± 539 versus 2636 ± 473 g, p < 0.001). We found a similar incidence of RDS and TTN in both groups. The multiple regression analysis showed cesarean delivery and lower gestational age were independently associated with RDS and TTN.Conclusion: GDM, per se, is not a major contributor to RDS in late pre-term infants. Rather, the combination of prematurity and cesarean birth act independently to increase the risk of respiratory morbidity.

Factors Associated With Elevated Exhaled Nitric Oxide Fraction in Infants With Recurrent Respiratory Symptoms

A Kotaniemi-Syrjanen, LP Malmberg, K Malmstrom, AS Pelkonen, MJ Makela. Eur Respir J. 2013;41(1):189–194 To evaluate the relationship between exhaled nitric oxide fraction (FeNO) and increased airway responsiveness, and to clarify whether there are any associations between these measures and risk factors for respiratory morbidity in infants with recurrent lower respiratory tract symptoms. Studied subjects were 444 children aged <3years with recurrent lower respiratory tract symptoms including wheeze, dry or productive cough, and/or shortness of breath. Subjects were assessed for FeNO, lung function tests, and the …

57: Effect of antenatal corticosteroids on respiratory morbidity in infants of women with diabetes

57: Effect of antenatal corticosteroids on respiratory morbidity in infants of women with diabetes

Respiratory outcomes in early childhood following antenatal vitamin C and E supplementation

BackgroundPrenatal antioxidant supplementation might influence fetal lung growth and development and reduce infant respiratory morbidity. The aim of this study was to test the hypothesis that infants of mothers at...

Mode of delivery and infant respiratory morbidity among infants born to HIV-1-infected women.

To estimate risk of infant respiratory morbidity associated with cesarean delivery before labor and ruptured membranes among HIV-1-infected women. In a prospective cohort study of HIV-1-infected women and their infants, mode of delivery was determined by clinicians at the participating sites. For this analysis, "elective cesarean delivery" was defined as any cesarean delivery, regardless of gestational age, without labor and with duration of ruptured membranes of less than 5 minutes. Nonelective cesarean deliveries were those performed after the onset of labor, rupture of membranes, or both. Vaginal delivery included normal spontaneous and instrument deliveries. Associations between mode of delivery and infant respiratory morbidity were assessed using chi or Fisher's exact test. Adjusted odds of respiratory distress syndrome by delivery mode were assessed using multivariable logistic regression. Among 1,194 mother-infant pairs, there were significant differences according to mode of delivery in median gestational age (weeks) at delivery (vaginal, n=566, median=38.8; nonelective cesarean, n=216, median=38.0; and elective cesarean, n=412, median 38.1; P<.001) and incidence of respiratory distress syndrome (vaginal, n=9, 1.6%, reference; nonelective cesarean, n=16, 7.4%; elective cesarean, n=18; 4.4%; (P<.001). In analyses adjusted for gestational age and birth weight, mode of delivery was not statistically significantly associated with infant respiratory distress syndrome (P=.10), although a trend toward an increased risk of respiratory distress syndrome among infants delivered by cesarean was suggested (nonelective cesarean adjusted odds ratio [OR] 2.32, 95% confidence interval [CI] 0.95-5.67; elective cesarean OR 2.56, 95% CI 1.01-6.48). Respiratory distress syndrome rates associated with elective cesarean delivery among HIV-1-infected women are low, comparable with published rates among uninfected women. There is minimal neonatal respiratory morbidity risk in near-term infants born by elective cesarean delivery to HIV-1-infected women. II.

Cochrane review: Chest physiotherapy for reducing respiratory morbidity in infants requiring ventilatory support

AbstractBackgroundChest physiotherapy (CPT) has been used in many neonatal nurseries around the world to improve airway clearance and treat lung collapse; however, the evidence to support its use has been conflicting. Despite the large number of studies there is very little evidence of sufficiently good quality on which to base current practice.ObjectivesTo assess the effects of active CPT techniques, such as percussion and vibration followed by suction compared with suction alone, on the respiratory system in infants receiving mechanical ventilation. Additionally, differences between types of active CPT techniques were assessed.Search strategyOur search included The Cochrane Library (Issue 2, 2007), MEDLINE (1966 to 2007), EMBASE (1988 to 2007), CINAHL, Science Citation Index, previous reviews including cross‐references, abstracts, conference proceedings and grey literature.Selection criteriaTrials in which ventilated newborn infants up to four weeks of age were randomly or quasi‐randomly assigned to receive active CPT or suction alone. Infants receiving CPT for the extubation period were excluded.Data collection and analysisTwo review authors independently conducted quality assessments and data extraction for included trials. We analysed data for individual trial results using relative risk (RR) and mean difference (MD). Results are presented with 95% confidence intervals (CI). Due to insufficient data, we could not undertake meta‐analysis.Main resultsThree trials involving 106 infants were included in this review. In one trial (n = 20) CPT was no better than standard care in clearing secretions. No increase in the risk of intraventricular haemorrhage was noted. Two trials compared different types of active CPT. One trial (n = 56) showed that non‐resolved atelectasis was reduced in more neonates receiving the lung squeezing technique (LST) when compared to postural drainage, percussion and vibration (PDPV) (RR 0.25; 95% CI 0.11 to 0.57). No difference in secretion clearance or in the rate of intraventricular haemorrhage or periventricular leucomalacia was demonstrated. The other trial (n = 30) showed that the use of percussion or 'cupping' resulted in an increased incidence of hypoxaemia (RR 0.53; 95% CI 0.28 to 0.99) and increased oxygen requirements (MD ‐9.68; 95% CI ‐14.16 to ‐5.20) when compared with contact heel percussion. There was insufficient information to adequately assess important short and longer‐term outcomes, including adverse effects.Authors' conclusionsThe results of this review do not provide sufficient evidence on which to base clinical practice. There is a need for larger randomised controlled trials to address these issues.Plain Language SummaryChest physiotherapy for reducing respiratory morbidity in infants requiring ventilatory supportThere is not enough evidence to determine whether active chest physiotherapy is of benefit to neonates on mechanical ventilation. Babies who require mechanical ventilation are at risk of lung collapse from increased secretions. Chest physiotherapy (patting or vibrating the chest) is used to improve clearance of secretions from the airway to try to prevent lung collapse. This review found no clear overall benefit or harm from chest physiotherapy. Some individual chest physiotherapy techniques were more beneficial than others in resolving atelectasis and maintaining oxygenation. These results do not support one technique over another. Due to the limited number, poor quality and age of trials in this review, there is not enough evidence to determine whether or not chest physiotherapy is beneficial or harmful in the treatment of infants being ventilated in today's intensive care units. Further good quality trials are needed to address this issue.

Genomewide Association Analysis of Respiratory Syncytial Virus Infection in Mice

Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infection in infants, with about half being infected in their first year of life. Yet only 2 to 3% of infants are hospitalized for RSV infection, suggesting that individual susceptibility contributes to disease severity. Previously, we determined that AKR/J (susceptible) mice developed high lung RSV titers and showed delayed weight recovery, whereas C57BL/6J (resistant) mice demonstrated low lung RSV titers and rapid weight recovery. In addition, we have reported that gene-targeted mice lacking the cystic fibrosis transmembrane conductance regulator (Cftr; ATP-binding cassette subfamily C, member 7) are susceptible to RSV infection. For this report, recombinant backcross and F2 progeny derived from C57BL/6J and AKR/J mice were infected with RSV, their lung titers were measured, and quantitative trait locus (QTL) analysis was performed. A major QTL, designated Rsvs1, was identified on proximal mouse chromosome 6 in both recombinant populations. Microarray analysis comparing lung transcripts of the parental strains during infection identified several candidate genes that mapped to the Rsvs1 interval, including Cftr. These findings add to our understanding of individual RSV susceptibility and strongly support a modifier role for CFTR in RSV infection, a significant cause of respiratory morbidity in infants with cystic fibrosis.