Christian Wieg

Avoidance of mechanical ventilation by surfactant treatment of spontaneously breathing preterm infants (AMV): an open-label, randomised, controlled trial.

BACKGROUND Surfactant is usually given to mechanically ventilated preterm infants via an endotracheal tube to treat respiratory distress syndrome. We tested a new method of surfactant application to spontaneously breathing preterm infants to avoid mechanical ventilation. METHOD In a parallel-group, randomised controlled trial, 220 preterm infants with a gestational age between 26 and 28 weeks and a birthweight less than 1·5 kg were enrolled in 12 German neonatal intensive care units. Infants were independently randomised in a 1:1 ratio with variable block sizes, to standard treatment or intervention, and randomisation was stratified according to centre and multiple birth status. Masking was not possible. Infants were stabilised with continuous positive airway pressure and received rescue intubation if necessary. In the intervention group, infants received surfactant treatment during spontaneous breathing via a thin catheter inserted into the trachea by laryngoscopy if they needed a fraction of inspired oxygen more than 0·30. The primary endpoint was need for any mechanical ventilation, or being not ventilated but having a partial pressure of carbon dioxide more than 65 mm Hg (8·6 kPa) or a fraction of inspired oxygen more than 0·60, or both, for more than 2 h between 25 h and 72 h of age. Analysis was by intention to treat. This study is registered, number ISRCTN05025922. FINDINGS 108 infants were assigned to the intervention group and 112 infants to the standard treatment group. All infants were analysed. On day 2 or 3 after birth, 30 (28%) infants in the intervention group were mechanically ventilated versus 51 (46%) in the standard treatment group (number needed to treat 6, 95% CI 3-20, absolute risk reduction 0·18, 95% CI 0·30-0·05, p=0·008). 36 (33%) infants in the intervention group were mechanically ventilated during their stay in the hospital compared with 82 (73%) in the standard treatment group (number needed to treat: 3, 95% CI 2-4, p<0·0001). The intervention group had significantly fewer median days on mechanical ventilation, (0 days. IQR 0-3 vs 2 days, 0-5) and a lower need for oxygen therapy at 28 days (30 infants [30%] vs 49 infants [45%], p=0·032) compared with the standard treatment group. We recorded no differences between groups for mortality (seven deaths in the intervention group vs five in the standard treatment group) and serious adverse events (21 vs 28). INTERPRETATION The application of surfactant via a thin catheter to spontaneously breathing preterm infants receiving continuous positive airway pressure reduces the need for mechanical ventilation. FUNDING German Ministry of Research and Technology, University of Lübeck, and Chiesi Pharmaceuticals.

Surfactant without intubation in preterm infants with respiratory distress: first multi-center data.

BACKGROUND Recently in a report of a single center a method has been described to apply surfactant via a thin endotracheal catheter to very low birth weight infants spontaneously breathing with nasal continuous positive airway pressure. We now analyzed available multicenter data. PATIENTS AND METHODS In a multicenter study investigating genetic risk factors, clinical and outcome data and data of antenatal and postnatal treatment of infants with a birth weight below 1,500 g were prospectively recorded. The measures of infants treated with the new method of surfactant application were compared to those of infants who received standard care. The analysis was restricted to infants with a gestational age below 31 weeks (n=1,541). RESULTS 319 infants were treated with the new method and 1,222 with standard care. The need for mechanical ventilation during the first 72 h (29% vs. 53%, p<0.001), the rate of bronchopulmonary dysplasia defined as oxygen at 36 weeks of postmenstrual age (10.9 % vs. 17.5%, p=0.004) and the rate of death or bronchopulmonary dysplasia were significantly lower in the treatment group than in the standard care group. Surfactant, theophyllin, caffeine and doxapram were significantly more often and analgetics, catecholamines and dexamethasone were significantly less frequently used in the treatment group. CONCLUSIONS A new method of surfactant application was associated with a lower prevalence of mechanical ventilation and better pulmonary outcome. A prospective controlled trial is required to determine whether this approach is superior to standard care.

Genetic Polymorphisms of Hemostasis Genes and Primary Outcome of Very Low Birth Weight Infants

BACKGROUND. Recent investigations have reported an influence of thrombophilic mutations and antithrombotic risk factors with development of intraventricular hemorrhage. It was our objective for this study to investigate the impact of genetic polymorphisms of hemostasis genes on the primary outcome measures of sepsis, bronchopulmonary dysplasia, intraventricular hemorrhage, and periventricular leukomalacia in a large cohort of very low birth weight infants. METHODS. There were 586 very low birth weight infants enrolled prospectively in a multicenter trial between September 2003 and July 2005, and an additional 595 very low birth weight infants, who had been recruited in a previous prospective trial, were studied. DNA samples were taken by buccal swab, and genotypes of factor V Leiden mutation, prothrombin G20210A mutation, the factor VII-323 del/ins polymorphism, and the factor XIII-Val34Leu polymorphisms were determined by polymerase chain reaction and restriction enzyme digestion. RESULTS. In contrast to data published previously, the frequency of intraventricular hemorrhage or periventricular leukomalacia was not significantly influenced by any of the genetic variants tested. Carriers of the factor XIII-Val34Leu polymorphism, however, had a higher sepsis rate and a longer period of hospital care compared with noncarriers. The factor VII-323 del/ins polymorphism was found to be a potential protective factor against bronchopulmonary dysplasia. CONCLUSIONS. We could not confirm previously reported associations of hemostasis gene variants and development of intraventricular hemorrhage in very low birth weight infants. To better understand gene-disease associations in very low birth weight infants, the prospective development of large-scale cohorts with well-defined phenotypes and corresponding DNA samples is essential.

Less invasive surfactant administration is associated with improved pulmonary outcomes in spontaneously breathing preterm infants

Providing less invasive surfactant administration (LISA) to spontaneously breathing preterm infants has been reported to reduce mechanical ventilation and bronchopulmonary dysplasia (BPD) in randomised controlled trials. This large cohort study compared these outcome measures between LISA‐treated infants and controls.

Prophylactic use of Lactobacillus acidophilus/Bifidobacterium infantis probiotics and outcome in very low birth weight infants.

OBJECTIVE To evaluate outcome data in an observational cohort of very low birth weight infants of the German Neonatal Network stratified to prophylactic use of Lactobacillus acidophilus/Bifidobacterium infantis probiotics. STUDY DESIGN Within the observational period (September 1, 2010, until December 31, 2012, n=5351 infants) study centers were categorized into 3 groups based on their choice of Lactobacillus acidophilus/Bifidobacterium infantis use: (1) no prophylactic use (12 centers); (2 a/b) change of strategy nonuser to user during observational period (13 centers); and (3) use before start of observation (21 centers). Primary outcome data of all eligible infants were determined according to center-specific strategy. RESULTS The use of probiotics was associated with a reduced risk for necrotizing enterocolitis surgery (group 1 vs group 3: 4.2 vs 2.6%, P=.028; change of strategy: 6.2 vs 4.0%, P<.001), any abdominal surgery, and hospital mortality. Infants treated with probiotics had improved weight gain/day, and probiotics had no effect on the risk of blood-culture confirmed sepsis. In a multivariable logistic regression analysis, probiotics were protective for necrotizing enterocolitis surgery (OR 0.58, 95% CI 0.37-0.91; P=.017), any abdominal surgery (OR 0.7, 95% CI 0.51-0.95; P=.02), and the combined outcome abdominal surgery and/or death (OR 0.43; 95% CI 0.33-0.56; P<.001). CONCLUSIONS Our observational data support the use of Lactobacillus acidophilus/Bifidobacterium infantis probiotics to reduce the risk for gastrointestinal morbidity but not sepsis in very low birth weight infants.

Does the enteral feeding advancement affect short-term outcomes in very low birth weight infants?

Background and Objectives: Controversy exists regarding the optimal enteral feeding regimen of very low birth weight infants (VLBW). Rapid advancement of enteral feeding has been associated with an increased rate of necrotizing enterocolitis. In contrast, delaying enteral feeding may have unfavorable effects on nutrition, growth, and neurodevelopment. The aim is to compare the short-term outcomes of VLBW infants in tertiary care centers according to their enteral feeding advancement. Patients and Methods: We prospectively studied the influence of center-specific enteral feeding advancement in 1430 VLBW infants recruited from 13 tertiary neonatal intensive care units in Germany on short-term outcome parameters. The centers were post hoc stratified to “rapid advancement to full enteral feeds” (median duration of advancement to full enteral feeds ≤12.5 days; 6 centers), that is, rapid advancement (RA), or “slow advancement to full enteral feeds” (median duration of advancement to full enteral feeds >12.5 days; 7 centers), that is, slow advancement (SA). Results: VLBW infants born in centers with SA (n = 713) had a significantly higher rate of sepsis compared with VLBW infants born in centers with RA (n = 717), which was particularly evident for late-onset sepsis (14.0% vs 20.4%; P = 0.002). Furthermore, more central venous lines (48.6% vs 31.1%, P < 0.001) and antibiotics (92.4% vs 77.7%, P < 0.001) were used in centers with SA. Conclusions: Center differences in enteral feeding advancement occur and may have a significant impact on short-term outcomes such as nosocomial sepsis. Large, multicenter, prospective trials are required to further elucidate the optimal feeding strategy for VLBW infants.

Risk for late-onset blood-culture proven sepsis in very-low-birth weight infants born small for gestational age: a large multicenter study from the German Neonatal Network.

Background: It was the aim of this study to assess whether very-low-birth-weight (VLBW) infants born small for gestational age (SGA; birth weight less than 10th percentile) are at increased risk for late-onset sepsis. Methods: This was a prospective, multicenter study of the German Neonatal Network including VLBW infants from 23 to < 32 weeks post menstrual age born 2009–2011. Outcomes were compared between VLBW infants born SGA (birth weight less than tenth percentile according to gestational age and gender) and non-SGA infants. The main outcome measure was at least 1 episode of late-onset sepsis defined as blood-culture–confirmed clinical sepsis occurring at ≥72 hours of age. Results: 5886 VLBW infants were included. In SGA infants (n = 692), an increased incidence of late-onset sepsis was noted compared with non-SGA infants (20.1% vs. 14.3 %, P < 0.001). This difference was only observed among infants with a gestational age of 27 to < 32 weeks and attributed to sepsis episodes with coagulase-negative staphylococci (12.8% vs. 8.3%, P < 0.001). Different treatment modalities (eg more frequent use of central venous lines) and longer duration of invasive therapies (parenteral nutrition, mechanical ventilation, hospitalization) may account for the increased sepsis risk with coagulase-negative staphylococci in our SGA cohort. In a multivariate logistic regression analysis, higher gestational age [per week; odds ratio (OR): 0.75, 95% confidence interval (CI): 0.72–0.78, P< 0.0001], treatment with antenatal steroids (OR: 0.7, 95% CI: 0.53–0.92, P = 0.01), German descendance (OR: 0.76, 95% CI: 0.63–0.91, P = 0.003) and prophylaxis with glycopeptide antibiotics (OR: 0.64, 95% CI: 0.47–0.87, P = 0.005) were shown to be protective against late-onset sepsis. In contrast, longer duration of parenteral nutrition (per day; OR: 1.016, 95% CI: 1.011–1.021, P < 0.0001) and SGA were found to be risk factors (OR: 1.31, 95% CI: 1.02–1.68, P= 0.03). Conclusions: SGA contributes to the risk of late-onset sepsis in VLBW infants. Future studies are needed to investigate the underlying pathophysiology to guide individualized preventive measures in this vulnerable subgroup.

Short-term outcome of very-low-birthweight infants with arterial hypotension in the first 24 h of life

Objective To evaluate lowest mean arterial blood pressure during the first 24 h of life (minMAP24) in very-low-birthweight (VLBW) infants and to identify associations between hypotension and short-term outcome. Design Retrospective cohort analysis of the minMAP24 of 4907 VLBW infants with a gestational age <32 weeks in correlation with clinical data. Hypotension was defined as minMAP24 being lower than the median value of all patients of the same gestational age. Results MinMAP24 values correlated with gestational age. Median minMAP24 values of VLBW infants ≤29 weeks’ gestation were 1–2 mm Hg lower than gestational age in completed weeks. Hypotensive infants had a higher rate of intraventricular haemorrhage (IVH, 20.3% vs 15.9%, p<0.001), bronchopulmonary dysplasia (BPD, 19.2% vs 15.1%, p<0.001) and death (5.2% vs 3.0%, p<0.001). Multivariate logistic regression analyses, including potential confounders, confirmed these data. MinMAP24 was an independent risk factor for IVH (OR 0.97/mm Hg, 95% CI 0.96 to 0.99, p=0.003), BPD (OR 0.96/mm Hg, 95% CI 0.94 to 0.98, p<0.001) and mortality (OR 0.94/mm Hg, 95% CI 0.90 to 0.98, p=0.003). Conclusions Hypotension during the first 24 h of life is associated with adverse outcomes in VLBW infants. This underlines the need for randomised controlled trials on the use of vasoactive drugs in this vulnerable patient cohort.

Epidemic Microclusters of Blood-Culture Proven Sepsis in Very-Low-Birth Weight Infants: Experience of the German Neonatal Network

Introduction We evaluated blood culture-proven sepsis episodes occurring in microclusters in very-low-birth-weight infants born in the German Neonatal Network (GNN) during 2009–2010. Methods Thirty-seven centers participated in GNN; 23 centers enrolled ≥50 VLBW infants in the study period. Data quality was approved by on-site monitoring. Microclusters of sepsis were defined as occurrence of at least two blood-culture proven sepsis events in different patients of one center within 3 months with the same bacterial species. For microcluster analysis, we selected sepsis episodes with typically cross-transmitted bacteria of high clinical significance including gram-negative rods and Enterococcus spp. Results In our cohort, 12/2110 (0.6%) infants were documented with an early-onset sepsis and 235 late-onset sepsis episodes (≥72 h of age) occurred in 203/2110 (9.6%) VLBW infants. In 182/235 (77.4%) late-onset sepsis episodes gram-positive bacteria were documented, while coagulase negative staphylococci were found to be the most predominant pathogens (48.5%, 95%CI: 42.01–55.01). Candida spp. and gram-negative bacilli caused 10/235 (4.3%, 95%CI: 1.68% –6.83%) and 43/235 (18.5%) late-onset sepsis episodes, respectively. Eleven microclusters of blood-culture proven sepsis were detected in 7 hospitals involving a total 26 infants. 16/26 cluster patients suffered from Klebsiella spp. sepsis. The median time interval between the first patient’s Klebsiella spp. sepsis and cluster cases was 14.1 days (interquartile range: 1–27 days). First patients in the cluster, their linked cases and sporadic sepsis events did not show significant differences in short term outcome parameters. Discussion Microclusters of infection are an important phenomenon for late-onset sepsis. Most gram-negative cluster infections occur within 30 days after the first patient was diagnosed and Klebsiella spp. play a major role. It is essential to monitor epidemic microclusters of sepsis in surveillance networks to adapt clinical practice, inform policy and further improve quality of care.

Polymorphisms in the Renin-Angiotensin System and Outcome of Very-Low-Birthweight Infants

Background: The insertion/deletion polymorphism of the angiotensin-converting enzyme (ACE-ins/del) and the angiotensin II type 1 receptor 1166A/C polymorphism (ATR1166A/C) were reported to be associated with several unfavorable outcome parameters in preterm infants like bronchopulmonary dysplasia, persistent ductus arteriosus and impaired insulin sensitivity. Objective: To confirm the above-mentioned associations in a large cohort of very-low-birthweight (VLBW) infants. Method: Clinical data of VLBW infants were prospectively recorded. The ACE-ins/del polymorphism and the ATR1166A/C polymorphism were determined by polymerase chain reaction in 1,209 and 1,168 infants, respectively. Results: There was no significant association between ACE-ins/del or ATR1166A/C genotype and outcome parameters (death, intraventricular hemorrhage, sepsis, bronchopulmonary dysplasia, ventilation, supplemental oxygen at discharge, postnatal treatment with insulin, surgery for intestinal perforation/necrotizing enterocolitis/retinopathy of prematurity/persistent ductus arteriosus. Conclusion: Both known functional polymorphisms of the renin-angiotensin system do not seem to be associated with the outcome of VLBW infants.