Randomised crossover study on pulse oximeter readings from different sensors in very preterm infants.

OBJECTIVE: In extremely preterm infants, different target ranges for pulse oximeter saturation (SpO2) may affect mortality and morbidity. Thus, the impact of technical changes potentially affecting measurements should be assessed. We studied SpO2 readings from different sensors for systematic deviations. DESIGN: Single-centre, randomised, triple crossover study. SETTING: Tertiary neonatal intensive care unit. PATIENTS: 24 infants, born at <32 weeks' gestation, with current weight <1500 g and without right-to-left shunt via a patent ductus arteriosus. INTERVENTIONS: Simultaneous readings from three SpO2 sensors (Red Diamond (RD), Photoplethysmography (PPG), Low Noise Cabled Sensors (LNCS)) were logged at 0.5 Hz over 6 hour/infant and compared with LNCS as control using analysis of variance. Sensor position was randomly allocated and rotated every 2 hours. Seven different batches each were used. OUTCOMES: Primary outcome was the difference in SpO2 readings. Secondary outcomes were differences between sensors in the proportion of time within the SpO2-target range (90-95 (100)%). RESULTS: Mean gestational age at birth (±SD) was 274/7 (±23/7) weeks, postnatal age 20 (±20) days. 134 hours of recording were analysed. Mean SpO2 (±SD) was 94.0% (±3.8; LNCS) versus 92.2% (±4.0; RD; p<0.0001) and 94.5% (±3.9; PPG; p<0.0001), respectively. Mean SpO2 difference (95% CI) was -1.8% (-1.9 to -1.8; RD) and 0.5% (0.4 to 0.5; PPG). Proportion of time in target was significantly lower with RD sensors (84.8% vs 91.7%; p=0.0001) and similar with PPG sensors (91.1% vs 91.7%; p=0.63). CONCLUSION: There were systematic differences in SpO2 readings between RD sensors versus LNCS. These findings may impact mortality and morbidity of preterm infants, particularly when aiming for higher SpO2-target ranges (eg, 90-95%). TRIAL REGISTRATION NUMBER: DRKS00027285.

Catheter insertion depths in less-invasive surfactant administration.

INTRODUCTION: Less-invasive surfactant administration (LISA) under continuous positive airway pressure is increasingly used for the treatment of neonatal respiratory distress. Different procedures are described, but data on the optimal catheter insertion depth are sparse. OBJECTIVE: To generate data for recommending an optimal catheter insertion depth in LISA. METHODS: We examined 112 anterior-posterior chest X-rays from intubated infants and determined the carina's vertebral projection, whenever possible. After that, distances between the middle of cervical vertebra 4 (C4) and thoracic vertebra 2 and the middle of C4 to thoracic vertebra 3, respectively, were measured. Results were plotted against infant's weight. RESULTS: A weight-based chart and recommendations for the optimal intratracheal catheter position in infants with a body weight between 350 and 4000 g were created. CONCLUSIONS: Generated data offer standardisation and may thus help to find a balance between risk of surfactant reflux and unilateral surfactant administration.

Clinical evaluation of an application aid for less-invasive surfactant administration (LISA).

BACKGROUND: Less-invasive surfactant administration (LISA) is increasingly used. We investigated the feasibility of a new LISA-device (Neofact®) in neonates. DESIGN: Prospective observational pilot study with open-label LISA in two tertiary neonatal intensive care units. PATIENTS: 20 infants with a gestational age of ≥26+0/7 weeks and an indication for LISA (Respiratory Severity Score (RSS)≥5 or fraction of inspired oxygen (FiO2) ≥0.30). Infants with respiratory tract malformations or unavailability of an instructed neonatologist were excluded. MAIN OUTCOME MEASURES: Success of LISA, defined as laryngoscopy-confirmed intratracheal catheter position or a decrease in FiO2 by ≥0.05 or to 0.21, accompanied by an RSS decrease of ≥2; number of attempts needed for tracheal catheterisation. RESULTS: 20/57 screened infants were enrolled. Successful application occurred in 19/20 (95%). One application failed after three attempts. No device-related adverse events occurred. The median number of attempts was 2, success rate per attempt 19/31 (61%). CONCLUSION: LISA via Neofact® appears feasible.

Nasal insertion depths for neonatal intubation.

AIM: Data on the depth of nasal intubation in neonates are rare, although this is the preferred route in some countries. Therefore, recommendations on optimal nasal intubation depths based on gestational age (GA) and weight are desirable. METHODS: We determined the distances between the middle of thoracic vertebrae 2 (T2) and the tip of the endotracheal tube in 116 X-rays from nasally intubated neonates. The intubation depth (tip to nostril distance) that was documented in the digital patient's file was then corrected for this distance to reach an optimal nasal insertion depth. Results were plotted against the infant's GA and weight. RESULTS: GA-based and birthweight-based charts and formulas for the nasal intubation depth in infants with a GA between 24 and 43 weeks and body weight between 400 and 4500 g were created. CONCLUSIONS: Generated data may help in predicting optimal insertion depths for nasal intubation in neonates.