A pilot study of evaluation of semi-rigid and flexible catheters for less invasive surfactant administration in preterm infants with respiratory distress syndrome-a randomized controlled trial.

BACKGROUND: In respiratory distress syndrome, many neonatology centers worldwide perform minimal invasive surfactant application in premature infants, using small-diameter catheters for endotracheal intubation and surfactant administration. METHODS: In this single-center, open-label, randomized-controlled trial, preterm infants requiring surfactant administration after birth, using a standardized minimal invasive protocol, were randomized to two different modes of endotracheal catheterization: Flexible charrière-4 feeding tube inserted using Magill forceps (group 1) and semi-rigid catheter (group 2). Primary outcome was duration of laryngoscopy. Secondary outcomes were complication rate (intraventricular hemorrhage, soft-tissue damage in first week of life) and vital parameters during laryngoscopy. Between 2019 and 2020, 31 infants were included in the study. Prior to in-vivo testing, laryngoscopy durations were studied on a neonatal airway mannequin in students, nurses and doctors. RESULTS: Mean gestational age and birth weight were 27 + 6/7 weeks and 1009 g; and 28 + 0/7 weeks and 1127 g for group 1 and 2, respectively. Length of laryngoscopy was similar in both groups (61.1 s and 64.9 s) overall (p.77) and adjusted for weight (p.70) or gestational age (p.95). Laryngoscopy failed seven times in group 1 (43.8%) and four times (26.7%) in group 2 (p.46). Longer laryngoscopy was associated with lower oxygen saturation with lowest levels occurring after failed laryngoscopy attempts. Secondary outcomes were similar in both groups. In vitro data on 40 students, 40 nurses and 12 neonatologists showed significant faster laryngoscopy in students and nurses group 2 (p < .0001) unlike in neonatologists (p.13). CONCLUSION: This study showed no difference in laryngoscopy duration in endotracheal catheterization when comparing semi-rigid and flexible catheters for minimal invasive surfactant application in preterm infants. In accordance with preliminary data and in contrast to published in-vitro trials, experienced neonatologists were able to perform endotracheal catheterization using both semi-rigid and flexible catheters at similar rates and ease, in vitro and in vivo. TRIAL REGISTRATION: ClinicalTrials.gov. NCT05024435 Registered 27 August 2021-Retrospectively registered.

Breath-dependent pressure fluctuations in various constant- and variable-flow neonatal CPAP devices.

OBJECTIVE: In continuous positive airway pressure (CPAP) devices, pressure can be generated by two different mechanisms: either via an expiratory valve or by one or more jets. Valved CPAP devices are referred to as constant-flow devices, and jet devices are called variable-flow devices. Constant-flow CPAP devices are said to reduce the imposed work of breathing due to lower breath-dependent pressure fluctuations. The present study investigates the performance of various constant- and variable-flow CPAP devices in relation to breath-dependent pressure fluctuations. DESIGN: Experimental study comparing the pressure fluctuations incurred by seven neonatal CPAP devices attached to an active neonatal lung model. METHODOLOGY: Spontaneous breathing was simulated using a tidal volume of 6 ml at pressure levels of 5, 7, and 9 mbar. The main outcomes were respiratory pressure fluctuations, tidal volume, and end-expiratory pressure. RESULTS: All CPAP devices tested showed respiratory pressure fluctuations, varying from 0.631 to 3.466 mbar. The generated tidal volume correlated significantly with the pressure fluctuations (r = -0.947; p = 0.001) and varied between 5.550 and 6.316 ml. CPAP devices with jets showed no advantage over CPAP devices with expiratory valves. End-expiratory pressure in the nose deviated from the set pressure between -1.305 and 0.644 mbar and varied depending on whether the pressure was measured in the device or in the tube extending to the nose. CONCLUSION: During standard spontaneous breathing, breath-dependent pressure fluctuations in constant- and variable-flow devices are comparable. Pressure measurements taken in the tubing system can lead to a considerable deviation of the applied pressure.

When synchronized isn't synchronous- an experimental benchmarking study on the efficiency of SIMV in very-low-birth weight premature infants.

BACKGROUND: Synchronized ventilation promotes a patient's ability to breathe spontaneously by providing intermittent, mechanical-controlled respiration that is synchronized with the patient's own efforts. In "synchronized-intermittent-mandatory-ventilation" SIMV, assisted ventilation is regulated by frequency settings which dictate the interval at which the ventilator becomes sensitive to respiratory efforts and responds with an assisted breath. SIMV has become one of the most widely used modes of ventilation in neonates. Using a neonatal-active-lung-model (NALM), this in-vitro benchmark study investigated how well synchronization works in SIMV with several ventilators. METHODS: The competence of eight ventilators was tested using a NALM simulator representing a preterm infant weighing approximately 1500 grams. Two conditions were explored: first, the ventilators were set to a constant ventilation rate, while the NALM was adjusted to frequencies equal to and below this ventilation rate. The second condition varied the ventilators' rates while the NALM frequency was held constant. Correctly triggered breaths were counted and displayed as a percentage (%) of the total potential triggerable breaths. RESULTS: Performance among devices significantly differed, ranging from a low 38.9% competency to a max of 71.7% under the first condition, and 70.7% to 100% under the second condition. CONCLUSIONS: At high SIMV frequencies, synchronization between the patient and ventilator becomes increasingly limited. Despite their identical ventilator functions, SIMV algorithms of the various manufacturers and models tested, deliver ventilation rates with significantly different degrees of synchronization; not only in comparison to each other, but also in their own ability to continuously and effectively synchronize breaths under variable conditions, typical of preterm lungs.

Introduction and feeding practices of solid food in preterm infants born in Salzburg!

BACKGROUND: It is shown that meeting the increased nutritional demand of preterm infants from birth is not only important for survival but essentially contributes to the infants` overall development and long-term health. While there are established guidelines for weaning term infants, evidence regarding preterm infants is scarce and less precise. The aim of this study was to identify the current practices on introducing solids to preterm infants amongst caregivers in Salzburg and determine potential reasons for early weaning. METHODS: Altogether 68 infants born between 24 0/7 and 36 6/7 weeks were recruited and detailed structured interviews with the caregivers were conducted at 17 weeks corrected age. Weight, height and head circumference were collected. RESULTS: 52% of the study group received solids before the recommended 17 weeks corrected age. For this group the mean age being 13.77 ± 1.11 weeks corrected age. Premature introduction of solids significantly correlates with exclusively and early formula-feeding. 34% were weaned due to recommendation by their paediatrician. 23% of the preterm infants even received solids before 12 weeks corrected age, putting them at risks for developing obesity, celiac disease and diabetes. CONCLUSIONS: This study shows the necessity for clear guidelines regarding the introduction of complementary feeding in preterm infants as well as the importance of their implementation. Caregivers should receive information on this topic early enough and they should fully understand the difference between chronological and corrected age.