Repeated intravenous doses of human umbilical cord-derived mesenchymal stromal cells for bronchopulmonary dysplasia: results of a phase 1 clinical trial with 2-year follow-up.

BACKGROUND: Currently, there is a lack of effective treatments or preventive strategies for bronchopulmonary dysplasia (BPD). Pre-clinical studies with mesenchymal stromal cells (MSCs) have yielded encouraging results. The safety of administering repeated intravenous doses of umbilical cord tissue-derived mesenchymal stromal cells (UC-MSCs) has not yet been tested in extremely-low-gestational-age newborns (ELGANs). AIMS: to test the safety and feasibility of administering three sequential intravenous doses of UC-MSCs every 7 days to ELGANs at risk of developing BPD. METHODS: In this phase 1 clinical trial, we recruited ELGANs (birth weight ≤1250 g and ≤28 weeks in gestational age [GA]) who were on invasive mechanical ventilation (IMV) with FiO2 ≥ 0.3 at postnatal days 7-14. Three doses of 5 × 106/kg of UC-MSCs were intravenously administered at weekly intervals. Adverse effects and prematurity-related morbidities were recorded. RESULTS: From April 2019 to July 2020, 10 patients were recruited with a mean GA of 25.2 ± 0.8 weeks and a mean birth weight of 659.8 ± 153.8 g. All patients received three intravenous UC-MSC doses. The first dose was administered at a mean of 16.6 ± 2.9 postnatal days. All patients were diagnosed with BPD. All patients were discharged from the hospital. No deaths or any serious adverse events related to the infusion of UC-MSCs were observed during administration, hospital stays or at 2-year follow-up. CONCLUSIONS: The administration of repeated intravenous infusion of UC-MSCs in ELGANs at a high risk of developing BPD was feasible and safe in the short- and mid-term follow-up.

Randomised trial of dobutamine versus placebo for low superior vena cava flow in preterm infants: Long-term neurodevelopmental outcome.

AIM: Although circulatory impairment during the transitional circulation associates morbidity and mortality, its treatment remains controversial. In a pilot trial on circulatory impairment defined as low superior vena cava (SVC) flow, dobutamine (Db) versus placebo (PL) showed a trend towards improved short-term outcomes. The purpose of this study was to report on the long-term outcome of the infants who were observed for SVC flow patterns. METHODS: Among the 126 infants <31 weeks of gestation prospectively scanned from birth, 28 presented low SVC flow within the first 24 h after birth and received Db (n = 16) or PL (n = 12). Follow-up of survivors included motor assessment and Bayley Scales II or III at 2 years, and the Reynolds Intellectual Assessment Scale at 6 years. Neurodevelopmental impairment (NDI) was defined as: cerebral palsy (Gross Motor Function Classification System ≥ level 2), or a cognitive function score < -2 standard deviations; or moderate or severe hearing or visual impairment. Db group, PL group and normal-flow group were compared. RESULTS: Eighteen infants died (Db: 5; PL: 2; normal flow group: 11, P = 0.1). Follow-up in survivors was accomplished in 80% and 55% of the cohort at 2 years and 6 years, respectively. No significant difference in the combined outcome (mortality or NDI) was found between the groups (42% Db, 36% PL, 30% normal flow group). CONCLUSIONS: This exploratory analysis did not show any differences in the long-term outcome of infants according to SVC flow patterns or its treatment early after birth.

Validity of Biomarkers of Early Circulatory Impairment to Predict Outcome: A Retrospective Analysis.

Objectives: The definition of circulatory impairment in the premature infant is controversial. Current research suggests overdiagnosis and overtreatment. We aimed to analyse which biomarkers move clinicians to initiate cardiovascular treatment (CVT). The prognostic capacity for adverse outcome (death and/or moderate-severe brain damage by cranial ultrasound at term equivalent) of these biomarkers was evaluated. Study Design: Retrospective data analysis from preterm infants enrolled in a placebo-controlled trial on dobutamine for low superior vena cava (SVC) flow, who showed normal SVC flow within the first 24 h (not randomized). Five positive biomarkers were considered: MABP < gestational age (GA)-1 mmHg; MABP < GA-5 mmHg; lactate > 4 mmol/L; BE < -9 mmol/L; SVC flow <51 ml/kg/min. Results: Ninety eight infants formed the study cohort. Thirty six received CVT (2-95 h). Logistic regression models adjusted for gestational age showed a positive association between CVT and the risk of death or moderate-severe abnormal cranial ultrasound at term equivalent [(OR 5.2, 95%CI: 1.8-15.1) p = 0.002]. MABP < GA-1 mmHg and lactate > 4 mmol/L were the most prevalent biomarkers at start of treatment. Low BE, high serum lactate and low SVC flow at first echocardiography showed a trend toward being associated with adverse outcome, although not statistically significant. Conclusions: Low blood pressure and high lactate are the most prevalent biomarkers used for CVT prescription. Lactic acidosis and low SVC flow early after birth showed a trend toward being associated with adverse outcome. These findings support using a combination of biomarkers for inclusion in a placebo-controlled trial on CVT during transitional circulation.

Exploring clinical, echocardiographic and molecular biomarkers to predict bronchopulmonary dysplasia.

INTRODUCTION: Bronchopulmonary dysplasia (BPD) is the most common chronic lung disease in childhood, related to prematurity, and the most common cause of pulmonary hypertension (PH) secondary to pulmonary disease in children. Moderate and severe BPD have a worse outcome and relate more frequently with PH. The prediction of moderate or severe BPD development in extremely premature newborns is vital to implement preventive strategies. Starting with the hypothesis that molecular biomarkers were better than clinical and echocardiographic factors, this study aims to explore the ability of clinical, echocardiographic and analytical variables to predict moderate or severe BPD in a cohort of extremely preterm infants. PATIENTS AND METHODS: We designed a prospective longitudinal study, in which we followed a cohort of preterm newborns (gestational age <28 weeks and weight ≤ 1250 grams). In these newborns we recorded weekly clinical and echocardiographic variables as well as blood and tracheal aspirate samples, to analyze molecular biomarkers (IL-6, IL-1, IP10, uric acid, HGF, endothelin-1, VEGF, CCL5). Variables and samples were collected since birth up to week 36 (postmenstrual age), time-point at which the diagnosis of BPD is established. RESULTS: We included 50 patients with a median gestational age of 26 weeks (IQR 25-27) and weight of 871 g (SD 161,0) (range 590-1200g). Three patients were excluded due to an early death. Thirty-five patients (74.5%) developed BPD (mild n = 14, moderate n = 15, severe n = 6). We performed a logistic regression in order to identify risk factors for moderate or severe BPD. We compared two predictive models, one with two variables (mechanical ventilation and inter-ventricular septum flattening), and another-one with an additional molecular biomarker (ET-1). CONCLUSIONS: The combination of clinical and echocardiographic variables is a valuable tool for determining the risk of BPD. We find the two variable model (mechanical ventilation and echocardiographic signs of PH) more practical for clinical and research purposes. Future research on BPD prediction should be oriented to explore the potential role of ET-1.

Sevoflurane for Short Painful Procedures in the Neonatal Intensive Care Unit.

OBJECTIVE: The aim of this study is to evaluate the use and safety of a sedation protocol with sevoflurane for short painful procedures in newborns. STUDY DESIGN: This was a prospective and observational study conducted in a tertiary neonatal intensive care unit. Sevoflurane was recommended in patients undergoing an invasive procedure of short length, especially in those with spontaneous breathing or without venous access. Its safety and efficacy was assessed by continuous monitoring of respiratory and hemodynamic variables and clinical data recording. RESULTS: Sevoflurane was used for 39 procedures, the main indications were: intravitreal bevacizumab injection (12), central venous catheterization (11), and biopsy (6). The median administration length was 14 minutes (range: 5-65 minutes). The median minimum dose was 1.5% (range: 1-3%). The median maximum dose was 2.5% (range: 1-6%). An effective control of nociceptive manifestations was achieved in 35 cases (90%). No major adverse effects were noticed. Main adverse effects were hypotension (8), desaturation (4), and apnea (3). All of them were solved by decreasing (14) or discontinuing (1) the administration of sevoflurane. CONCLUSION: Sevoflurane is relatively easy to use and provides an optimal control of pain-related symptoms. Its prescription should be individualized and more long-term follow-up data are needed.

Off-label mesenchymal stromal cell treatment in two infants with severe bronchopulmonary dysplasia: clinical course and biomarkers profile.

BACKGROUND: Bronchopulmonary dysplasia (BPD) is the most prevalent sequelae of premature birth, for which therapeutic options are currently limited. Mesenchymal stromal cells (MSCs) are a potential therapy for prevention or reversal of BPD. SERIES OF CASES: We report on two infants with severe BPD in whom off-label treatment with repeated intravenous doses of allogeneic bone marrow-derived MSCs were administered. We analyzed the temporal profile of serum and tracheal cytokines and growth factors as well as safety, tolerability and clinical response. The administration of repeated intravenous doses of MSCs in two human babies with severe and advanced BPD was feasible and safe and was associated with a decrease of pro-inflammatory molecules and lung injury biomarkers. Both patients were at very advanced stages of BPD with very severe lung fibrosis and did not survive the disease. CONCLUSIONS: MSCs are a promising therapy for BPD, but they should be administered in early stages of the disease.

The economic impact of prematurity and bronchopulmonary dysplasia.

Bronchopulmonary dysplasia (BPD) is one of the most serious chronic lung diseases in infancy and one of the most important sequels of premature birth (prevalence of 15-50%). Our objective was to estimate the cost of BPD of one preterm baby, with no other major prematurity-related complications, during the first 2 years of life in Spain. Data from the Spanish Ministry of Health regarding costs of diagnosis-related group of preterm birth, hospital admissions and visits, palivizumab administration, and oxygen therapy in the year 2013 were analyzed. In 2013, 2628 preterm babies were born with a weight under 1500 g; 50.9% were males. The need for respiratory support was 2.5% needed only oxygen therapy, 39.5% required conventional mechanical ventilation, and 14.9% required high-frequency ventilation. The incidence of BPD was of 34.9%. The cost of the first 2 years of life of a preterm baby with BPD and no other major prematurity-related complications ranged between 45,049.81 € and 118,760.43 €, in Spain, depending on birth weight and gestational age. If the baby required home oxygen therapy or developed pulmonary hypertension, this cost could add up to 181,742.43 €. CONCLUSION: Prematurity and BPD have an elevated cost, even for public health care systems. This cost will probably increase in the coming years if the incidence and survival of preterm babies keeps rising. The development of new therapies and preventive strategies to decrease the incidence of BPD and other morbidities associated with prematurity should be a priority. What is known: • Bronchopulmonary dysplasia (BPD) is a serious chronic lung disease related with premature birth. • BPD is an increasing disease due to the up-rise in the number of premature births. What is new: • The economic cost of preterm birth and BPD has never before been estimated in Spain nor published with European data. • Preterm babies with BPD and a good clinical outcome carry also an important economic and social burden.

Pulmonary vein stenosis of ex-premature infants with pulmonary hypertension and bronchopulmonary dysplasia, epidemiology, and survival from a multicenter cohort.

BACKGROUND: Pulmonary vein stenosis is emerging as an important clinical problem in ex-premature infants. METHODS: We sought to describe the epidemiology of pulmonary vein stenosis affecting ex-premature infants by a multicenter retrospective cohort study of patients from seven children's hospitals diagnosed between 2000-2014. RESULTS: We identified 39 ex-premature patients (26 males, median gestational age 28 weeks range 22-36 weeks, birth weight 1.1 kg range 433-2645-g) with pulmonary vein stenosis. Median age at diagnosis was 6.5 months (1 month-6 years). Presentation with pulmonary hypertension occurred in 26/39 (67%) and 29/39 (74%) had bronchopulmonary dysplasia, 15 (39%) were born of twin pregnancies with unaffected twin siblings. A median of 5 (range 1-25) echocardiograms was performed prior to diagnosis. The diagnosis was made using echocardiography in 22/39 (56%), by multi-detector contrast computed tomography scan (CT) in 8/39 (21%), cardiac catheterization in 6/39 (15%) patients, magnetic resonance imaging in 3/39 (8%). Freedom from death or re-stenosis was 73% at 1-year, 55% at 2, 5, and 10 years. Factors associated with shorter survival or re-stenosis were stenosis of ≥3 pulmonary veins (P < 0.01), bilateral pulmonary vein stenosis (P < 0.01) small for gestational age (P = 0.05), aged <6 months at diagnosis (P < 0.01). CONCLUSION: Pulmonary vein stenosis of ex-premature infants is a complex problem with poor survival, delayed diagnosis, and unsatisfactory treatment. The lack of concordance in twins suggests epigenetic or environmental factors may play a role in the development of pulmonary vein stenosis. In ex-premature infants with pulmonary hypertension and bronchopulmonary dysplasia a focused echocardiographic assessment of the pulmonary veins is required with further imaging if the echocardiogram is inconclusive.

The SafeBoosC phase II clinical trial: an analysis of the interventions related with the oximeter readings.

BACKGROUND: The SafeBoosC phase II randomised clinical trial recently demonstrated the benefits of a combination of cerebral regional tissue oxygen saturation (rStO2) by near-infrared spectroscopy (NIRS) and a treatment guideline to reduce the oxygen imbalance in extremely preterm infants. AIMS: To analyse rStO2-alarm-related clinical decisions and their heterogeneity in the NIRS experimental group (NIRS monitoring visible) and their impact on rStO2 and SpO2. METHODS: Continuous data from NIRS devices and the alarms (area under the curve of the rStO2 out of range had accumulated 0.2%h during 10 min), clinical data at discrete time points and interventions prompted by the alarms were recorded. RESULTS: Sixty-seven infants had data that fulfilled the requirements for this analysis. 1107 alarm episodes were analysed. The alarm triggered a treatment guideline intervention in 25% of the cases; the type of intervention chosen varied among clinical sites. More than 55% of alarms were not followed by an intervention ('No action'); additionally, in 5% of alarms the rStO2 value apparently was considered non-reliable and the sensor was repositioned. The percentage of unresolved alarms at 30 min after 'No action' almost doubled the treatment guideline intervention (p<0.001). Changes in peripheral oxygen saturation (SpO2), were observed only after treatment guideline interventions. CONCLUSIONS: This study shows that 25% of rStO2 alarms were followed by a clinical intervention determined by the treatment guideline. However, the rStO2 and SpO2 returned to normal ranges after the intervention, supporting the notion that decisions taken by the clinicians were appropriate. TRIAL REGISTRATION NUMBER: ClinicalTrial.gov NCT01590316.

Randomized, Placebo-Controlled Trial of Dobutamine for Low Superior Vena Cava Flow in Infants.

OBJECTIVE: To gather information for a future confirmatory trial of dobutamine (DB) for circulatory impairment (ie, low superior vena cava [SVC] flow). STUDY DESIGN: A total of 127 infants born at < 31 weeks gestational age were serially scanned from birth to 96 hours after birth. The infants were randomly assigned to 2 groups and were treated with DB (stepwise dose increase, 5-10-15-20 µg/kg/min) or placebo if they had an SVC flow < 41 mL/kg/min within the first 24 hours after birth. The primary outcome measures were the achievement and maintenance of an SVC flow ≥ 41 mL/kg/min. Secondary outcome measures were the short-term evolution of clinical and biochemical variables, near-infrared spectroscopy, cranial Doppler ultrasound, and clinical outcomes. RESULTS: SVC flow increased throughout the first 96 hours for the entire cohort. All of the randomized infants (n = 28) except 2 achieved and maintained an SVC flow ≥ 41 mL/kg/min after intervention; however, the infants treated with DB (n = 16) showed a higher heart rate and improved base excess compared with those treated with placebo (n = 12). Low SVC flow was associated with low gestational age (P = .02) and poor condition at birth (P = .02). Low SVC flow significantly increased the risk of severe ischemic events (OR, 13; 95% CI, 2.4-69.2; P < .01). CONCLUSION: This exploratory trial demonstrates a tendency toward improved short-term clinical and biochemical perfusion variable outcomes in infants with low SVC flow treated with DB. TRIAL REGISTRATION: ClinicalTrials.gov (NCT01605279) and the European Clinical Trials Database (EurodraCT 2009-010901-35).

New time-frequency method for cerebral autoregulation in newborns: predictive capacity for clinical outcomes.

OBJECTIVE: To describe an alternative analysis in the frequency-domain of the temporal relationship between 2 biological signals and evaluate the method's predictive capacity for classifying infants at risk for an adverse outcome. STUDY DESIGN: We studied 54 infants (mean gestational age 27 weeks) with invasive mean arterial blood pressure monitoring. The bivariate autoregressive spectral coherence (BiAR-COH) method and the spectral coherence methods were used to analyze the relationship between spontaneous changes in mean arterial blood pressure and the near-infrared tissue oxygenation index. RESULTS: The mean postnatal age at the beginning and end of the autoregulation study was 6.0 (3.0) and 29.0 (7.5) hours, respectively. The BiAR-COH was superior to the spectral coherence in predicting low superior vena cava (SVC) flow (≤ 41 mL/kg per minute), with an area under the receiver operating characteristic curve of 0.84 (95% CI, 0.77-0.90; P < .001). The BiAR-COH threshold for identifying low SVC flow was 0.577, with 0.8 sensitivity and 0.76 specificity. After adjusting for the repeated measures effect (multiple epochs) in a given patient, the averaged BiAR-COH per patient and averaged COH per patient were calculated as the average value per patient. The pBiAR-COH (but not the pCOH) was associated with intraventricular hemorrhage grades 3 and 4 and predicted mortality. CONCLUSIONS: The BiAR-COH classifier identifies low SVC flow infants who are at risk for brain hypoperfusion. The BiAR-COH is superior to frequency domain methods in predicting adverse outcomes in infants.

Phase 1 study of two inodilators in neonates undergoing cardiovascular surgery.

BACKGROUND: Inodilators are routinely used in cardiovascular surgery with cardiopulmonary bypass (CPB). Information regarding safety and tolerability of the novel molecule, levosimendan (LEVO), in newborns is anecdotal; no pharmacokinetic data in this population are available. METHODS: This was a phase I, randomized, and blinded study. Neonates undergoing surgical repair for congenital heart defects received stepwise dose increases of milrinone (MR; 0.5-1 µg/kg/min, n = 9) or LEVO (0.1-0.2 µg/kg/min, n = 11) as an i.v. continuous infusion, starting before CPB. Infants had continuous, time-locked, physiological, and near-infrared spectroscopy (NIRS) (cerebral and peripheral) recordings during the first 24 h, and at 48 and 96 h postsurgery. Serial biochemistry and pharmacokinetic studies were performed. RESULTS: During the first 24 h postsurgery, patients showed time-related, group-independent increased cerebral tissue oxygenation and decreased diastolic blood pressure; in addition, group-dependent differences in heart rate and peripheral perfusion were found. Early postsurgery, MR-treated infants showed lower pH, higher glycemia, and higher inotrope score. The groups differed in cerebral NIRS-derived variables from 24 to 96 h. Study drug withdrawal at 96 h was more frequent with LEVO. LEVO intermediate metabolites were detected in plasma at day 14 after surgery. CONCLUSION: LEVO is well tolerated in critically ill neonates. LEVO may have advantages over MR in terms of the dosing regimen.