Nasal high frequency oscillatory highflow therapy in preterm infants: A randomized crossover trial.

OBJECTIVES: To assess the clinical efficacy, safety, and potential physiological mechanisms of highflow therapy with superimposed high frequency oscillations ("osciflow"). STUDY DESIGN: In this prospective, randomized, single center crossover trial, 30 preterm infants were randomized to receive osciflow or highflow therapy first, each for 180 min. During osciflow, an oscillatory amplitude of 20 mbar and a frequency of 6 Hz were set. The flow rate was 4 L/min during both interventions. Primary outcome was the paired difference in the combined number of desaturations (SpO2 < 80%) and bradycardia (heart rate <80 beats per min) between interventions. Safety outcomes included nasal trauma, pneumothorax and treatment failure, and a pain score was assessed. In 20 infants, electrical impedance tomography (EIT) recordings were performed to evaluate oscillatory (VOsc ) and tidal volumes (VT ) at the lung level. RESULTS: Infants with a mean (SD) postnatal age of 33.1 ± 1.2 weeks were included. The median (IQR) number of episodes of desaturation and bradycardia was 19.5 (6-49) during osciflow and 26 (6-44) during highflow therapy (paired difference -2; IQR -10 to 9; p = .37). There were no differences in safety outcomes and pain scores. During osciflow, EIT recordings showed a signal at 6 Hz, which was not detectable during highflow. Corresponding mean (SD) VOsc /VT ratio was 9% (±5%). CONCLUSIONS: In preterm infants, osciflow did not reduce the number of desaturations and bradycardia compared with highflow therapy. Although VOsc were transmitted to the lung during osciflow, their magnitude was small. Osciflow was safe and well tolerated.

Tidal volumes during delivery room stabilization of (near) term infants.

BACKGROUND: We sought to assess tidal volumes in (near) term infants during delivery room stabilization. METHODS: Secondary analysis of a prospective study comparing two facemasks used for positive pressure ventilation (PPV) in newborn infants ≥ 34 weeks gestation. PPV was provided with a T-piece device with a PIP of 30 cmH2O and positive end-expiratory airway pressure of 5 cmH2O. Expired tidal volumes (Vt) were measured with a respiratory function monitor. Target range for Vt was defined to be 4 - 8 ml/kg. RESULTS: Twenty-three infants with a median (IQR) gestational age of 38.1 (36.4 - 39.0) weeks received 1828 inflations with a median Vt of 4.6 (3.3 - 6.2) ml/kg. Median Vt was in the target range in 12 infants (52%), lower in 9 (39%) and higher in 2 (9%). Thirty-six (25-27) % of the inflations were in the target rage over the duration of PPV while 42 (25 - 65) % and 10 (3 - 33) % were above and below target range. CONCLUSIONS: Variability of expiratory tidal volume delivered to term and late preterm infants was wide. Reliance on standard pressures and clinical signs may be insufficient to provide safe and effective ventilation in the delivery room. TRIAL REGISTRATION: This is a secondary analysis of a prospectively registered randomized controlled trial (ACTRN12616000768493).

The DELUX study: development of lung volumes during extubation of preterm infants.

OBJECTIVE: To measure changes in end-expiratory lung impedance (EELI) as a marker of functional residual capacity (FRC) during the entire extubation procedure of very preterm infants. METHODS: Prospective observational study in preterm infants born at 26-32 weeks gestation being extubated to non-invasive respiratory support. Changes in EELI and cardiorespiratory parameters (heart rate, oxygen saturation) were recorded at pre-specified events during the extubation procedure compared to baseline (before first handling of the infant). RESULTS: Overall, 2912 breaths were analysed in 12 infants. There was a global change in EELI during the extubation procedure (p = 0.029). EELI was lowest at the time of extubation [median (IQR) difference to baseline: -0.30 AU/kg (-0.46; -0.14), corresponding to an FRC loss of 10.2 ml/kg (4.8; 15.9), padj = 0.004]. The biggest EELI loss occurred during adhesive tape removal [median change (IQR): -0.18 AU/kg (-0.22; -0.07), padj = 0.004]. EELI changes were highly correlated with changes in the SpO2/FiO2 ratio (r = 0.48, p < 0.001). Forty per cent of FRC was re-recruited at the tenth breath after the initiation of non-invasive ventilation (p < 0.001). CONCLUSIONS: The extubation procedure is associated with significant changes in FRC. This study provides novel information for determining the optimal way of extubating a preterm infant. IMPACT: This study is the first to examine the development of lung volumes during the entire extubation procedure including the impact of associated events. The extubation procedure significantly affects functional residual capacity with a loss of approximately 10 ml/kg at the time of extubation. Removal of adhesive tape is the major contributing factor to FRC loss during the extubation procedure. Functional residual capacity is regained within the first breaths after initiation of non-invasive ventilation and is further increased after turning the infant into the prone position.

Surfactant Nebulization to Prevent Intubation in Preterm Infants: A Systematic Review and Meta-analysis.

CONTEXT: Surfactant nebulization (SN) may offer a safe alternative for surfactant administration in respiratory distress syndrome of preterm infants. OBJECTIVE: To evaluate the efficacy of SN for the prevention of early intubation. DATA SOURCES: Medline, Embase, The Cochrane Library, clinicaltrials.gov, published abstracts, and references of relevant articles were searched through March 23, 2021. STUDY SELECTION: Randomized clinical trials of preterm infants <37 weeks' gestation comparing SN with noninvasive respiratory support or intratracheal surfactant application. DATA EXTRACTION: Two reviewers extracted data and assessed risk of bias from included studies separately and blinded. Data were pooled by using a fixed-effects model. Subgroups (gestational age, type of nebulizer, surfactant type, and dosage) were evaluated. Primary outcome was intubation rate at 72 hours after birth. RESULTS: Nine studies recruiting 1095 infants met inclusion criteria. SN compared with standard care significantly reduced intubation rate at 72 hours after birth (226 of 565 infants [40.0%] vs 231 of 434 infants [53.2%]; risk ratio [RR]: 0.73, 95% confidence interval [CI]: 0.63-0.84; number needed to treat: 8; 95% CI: 5-14]). Prespecified subgroup analysis identified important heterogeneity: SN was most effective in infants ≥28 weeks' gestation (RR: 0.70, 95% CI: 0.60-0.82), with a pneumatically driven nebulizer (RR: 0.52, 95% CI: 0.40-0.68) and in infants receiving ≥200 mg/kg and animal-derived surfactant (RR: 0.63, 95% CI: 0.52-0.75). No differences in neonatal morbidities or mortality were identified. LIMITATIONS: Quality of evidence was low owing to risk of bias and imprecision. CONCLUSIONS: SN reduced the intubation rate in preterm infants with a higher efficacy for specific subgroups. There was no difference in relevant neonatal morbidities or mortality.

Psychomotor vigilance task demonstrates impaired vigilance in disorders with excessive daytime sleepiness.

STUDY OBJECTIVE: The Psychomotor Vigilance Task (PVT) is one of the leading assays of sustained vigilant attention in sleep research and highly sensitive to the effects of sleep loss. Even though PVT is widely used in sleep deprivation studies, little is known about PVT performance in patients suffering from sleep-wake disorders. We aimed to quantify the impact of sleep-wake disorders on PVT outcome measures and examine whether PVT can distinguish between healthy controls and patients with sleep-wake disorders and whether PVT can distinguish between three different disorders that express excessive daytime sleepiness. METHODS: We compared PVT data of 143 patients and 67 age- and gender-matched healthy controls. Patients were diagnosed with one of the following sleep-wake disorders: narcolepsy with cataplexy (n = 20), insufficient sleep syndrome (ISS, n = 67) and hypersomnia (HS, n = 56). Several PVT outcomes were analyzed: reciprocal mean reaction time, response variability, number of lapses, number of false reaction time, slowest and fastest 10% of reaction time, and duration of lapses. RESULTS: PVT performance was generally better in healthy controls than in patients with any of the sleep-wake disorders analyzed. Patients with narcolepsy and HS performed worse on PVT than subjects with ISS. In controls, but not in patients, older subjects had slower reactions times and higher response variability in PVT. CONCLUSIONS: PVT performance shows different patterns in patients with different sleep-wake disorders and control subjects and may add useful information to the diagnostic work-up of sleep-wake disorders.

Pharmacovigilance in pregnancy: adverse drug reactions associated with fetal disorders.

OBJECTIVE: To provide the first update on drug safety profiles and adverse drug reactions (ADRs) associated with fetal disorders from the Swiss national ADR database. METHODS: We conducted a retrospective study using data from 202 pharmacovigilance reports on drug-associated fetal disorders from the Swiss national ADR database from 1990 to 2009. Evaluated aspects included administrative information on the report, drug exposure, and disorders. RESULTS: The ADR reporting frequency on the topic of fetal disorders has increased during the last 20 years, from only 1 report in 1991 to a maximum of 31 reports in 2008. Nervous system drugs were the most frequently reported drug group (40.2%) above all antidepressants and antiepileptics. The highest level of overall drug intake could be observed for the 1st trimester (85.4%), especially for the first 6 weeks of pregnancy. The most frequently reported types of fetal disorders were malformations (68.8%), especially those of the musculoskeletal and circulatory systems. A positive association was discovered between antiepileptics and malformations in general and in particular of the circulatory system and the eye, ear, face, and neck. CONCLUSIONS: The results suggest that the nervous system drug group bears an especially high risk for malformations. The most commonly identified drug exposures can help focus pharmacoepidemiologic efforts in drug-induced birth defects.