Angela Kribs

IMPORTANCE: Treatment of respiratory distress syndrome in premature infants with continuous positive airway pressure (CPAP) preserves surfactant and keeps the lung open but is insufficient in severe surfactant deficiency. Traditional surfactant administration is related to short periods of positive pressure ventilation and implies the risk of lung injury. CPAP with surfactant but without any positive pressure ventilation may work synergistically. This randomized trial investigated a less invasive surfactant application protocol (LISA). OBJECTIVE: To test the hypothesis that LISA increases survival without bronchopulmonary dysplasia (BPD) at 36 weeks' gestational age in extremely preterm infants. DESIGN, SETTING, AND PARTICIPANTS: The Nonintubated Surfactant Application trial was a multicenter, randomized, clinical, parallel-group study conducted between April 15, 2009, and March 25, 2012, in 13 level III neonatal intensive care units in Germany. The final follow-up date was June 21, 2012. Participants included 211 of 558 eligible (37.8%) spontaneously breathing preterm infants born between 23.0 and 26.8 weeks' gestational age with signs of respiratory distress syndrome. In an intention-to-treat design, infants were randomly assigned to receive surfactant either via a thin endotracheal catheter during CPAP-assisted spontaneous breathing (intervention group) or after conventional endotracheal intubation during mechanical ventilation (control group). Analysis was conducted from September 6, 2012, to June 20, 2013. INTERVENTION: LISA via a thin catheter. MAIN OUTCOMES AND MEASURES: Survival without BPD at 36 weeks' gestational age. RESULTS: Of 211 infants who were randomized, 104 were randomized to the control group and 107 to the LISA group. Of the infants who received LISA, 72 (67.3%) survived without BPD compared with 61 (58.7%) of those in the control group. The reduction in absolute risk was 8.6% (95% CI, -5.0% to 21.9%; P = .20). Intervention group infants were less frequently intubated (80 infants [74.8%] vs 103 [99.0%]; P < .001) and required fewer days of mechanical ventilation. Significant reductions were seen in pneumothorax (5 of 105 intervention group infants [4.8%] vs 13 of 103 12.6%]; P = .04) and severe intraventricular hemorrhage (11 infants [10.3%] vs 23 [22.1%]; P = .02), and the combined survival without severe adverse events was increased in the intervention group (54 infants [50.5%] vs 37 [35.6%]; P = .02; absolute risk reduction, 14.9; 95% CI, 1.4 to 28.2). CONCLUSIONS AND RELEVANCE: LISA did not increase survival without BPD but was associated with increased survival without major complications. Because major complications are related to lifelong disabilities, LISA may be a promising therapy for extremely preterm infants. TRIAL REGISTRATION: isrctn.org Identifier: ISRCTN64011614.

BACKGROUND: Targeted therapies to stabilize the clinical manifestations and prolong pregnancy in preeclampsia do not exist. Soluble fms-like tyrosine kinase 1 (sFlt-1), an alternatively spliced variant of the vascular endothelial growth factor receptor 1, induces a preeclampsia-like phenotype in experimental models and circulates at elevated levels in human preeclampsia. Removing sFlt-1 may benefit women with very preterm (<32 weeks) preeclampsia. METHODS AND RESULTS: We first show that negatively charged dextran sulfate cellulose columns adsorb sFlt-1 in vitro. In 5 women with very preterm preeclampsia and elevated circulating sFlt-1 levels, we next demonstrate that a single dextran sulfate cellulose apheresis treatment reduces circulating sFlt-1 levels in a dose-dependent fashion. Finally, we performed multiple apheresis treatments in 3 additional women with very preterm (gestational age at admission 28, 30, and 27+4 weeks) preeclampsia and elevated circulating sFlt-1 levels. Dextran sulfate apheresis lowered circulating sFlt-1, reduced proteinuria, and stabilized blood pressure without apparent adverse events to mother and fetus. Pregnancy lasted for 15 and 19 days in women treated twice and 23 days in a woman treated 4 times. In each, there was evidence of fetal growth. CONCLUSIONS: This pilot study supports the hypothesis that extracorporeal apheresis can lower circulating sFlt-1 in very preterm preeclampsia. Further studies are warranted to determine whether this intervention safely and effectively prolongs pregnancy and improves maternal and fetal outcomes in this setting.

Preeclampsia is a devastating complication of pregnancy. Soluble Fms-like tyrosine kinase-1 (sFlt-1) is an antiangiogenic protein believed to mediate the signs and symptoms of preeclampsia. We conducted an open pilot study to evaluate the safety and potential efficacy of therapeutic apheresis with a plasma-specific dextran sulfate column to remove circulating sFlt-1 in 11 pregnant women (20-38 years of age) with very preterm preeclampsia (23-32 weeks of gestation, systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg, new onset protein/creatinine ratio >0.30 g/g, and sFlt-1/placental growth factor ratio >85). We evaluated the extent of sFlt-1 removal, proteinuria reduction, pregnancy continuation, and neonatal and fetal safety of apheresis after one (n=6), two (n=4), or three (n=1) apheresis treatments. Mean sFlt-1 levels were reduced by 18% (range 7%-28%) with concomitant reductions of 44% in protein/creatinine ratios. Pregnancy continued for 8 days (range 2-11) and 15 days (range 11-21) in women treated once and multiple times, respectively, compared with 3 days (range 0-14) in untreated contemporaneous preeclampsia controls (n=22). Transient maternal BP reduction during apheresis was managed by withholding pre-apheresis antihypertensive therapy, saline prehydration, and reducing blood flow through the apheresis column. Compared with infants born prematurely to untreated women with and without preeclampsia (n=22 per group), no adverse effects of apheresis were observed. In conclusion, therapeutic apheresis reduced circulating sFlt-1 and proteinuria in women with very preterm preeclampsia and appeared to prolong pregnancy without major adverse maternal or fetal consequences. A controlled trial is warranted to confirm these findings.

BACKGROUND: Spontaneous breathing supported by nasal continuous positive airway pressure (nCPAP) is thought to have some advantages compared with mechanical ventilation in extremely premature infants. In addition, early or prophylactic surfactant administration has been shown to be superior to delayed use. A strategy to combine these two principles was tested in our neonatal intensive care unit (NICU). The aim of this feasibility study was to describe the procedure and compare short-term results with a historical control. METHODS: The study took place in a level III NICU. In the observational period all extremely premature infants with clinical signs of moderate to severe respiratory distress syndrome despite nCPAP received 100 mg.kg(-1) of a natural surfactant preparation via an intratracheal catheter during spontaneous breathing. In the historical control period those infants were intubated and ventilated to receive surfactant. RESULTS: Twenty-nine of 42 infants fulfilled the criteria and were treated with the new approach. In five cases ventilation with manual bag was necessary after administration of surfactant but all infants could be retransferred to nCPAP within a few minutes. Ten infants were intubated later during the first 3 days. Mortality was 7% in the group of infants treated in this way and 12% in all infants treated during the observational period. Mortality was 35% in the historical control period. Morbidity was within ranges reported by other authors. CONCLUSIONS: Surfactant administration during nCPAP is feasible. First results indicate that early complications are rare. This warrants a prospective randomized trial.