Background: It would be advantageous for the treatment of neonatal respiratory distress syndrome if effective amounts of surfactant could be delivered by nebulization. Objective: To investigate lung deposition and distribution of nebulized porcine surfactant using an investigational eFlow® neonatal nebulizer. Methods: While lying on one side, 1-day-old piglets inhaled 200 mg·kg^-1 of nebulized surfactant via mask, nasal prongs, or tracheal tube. The surfactant was diluted with normal saline to 40 mg·ml^-1 and labeled with ^99mtechnetium-labelled nanocolloid. Undiluted surfactant (80 mg·ml^-1) was instilled tracheally in a fourth group. Each group had 8 animals. Lung deposition was measured by gamma scintigraphy, and deposition values were presented as a percentage of the nebulized or instilled dose. Results: The median lung deposition of inhaled surfactant was 5% (range 3-16) via mask, 14% (2-40) via prongs, and 45% (25-56) via tracheal tube (p < 0.05). It was 88% (71-96) with instillation. In all groups, the surfactant preferentially went to the dependent lung. Deposition ratios (upper lung/both lungs) were 0.32 (0.13-0.58), 0.15 (0.05-0.58), 0.16 (0.11-0.23), and 0.08 (0.03-0.46). Conclusions: Using this nebulizer, the lung depositions of porcine surfactant were 45% via endotracheal tube and 14% via nasal-continuous positive airway pressure (prongs). These figures might be physiologically relevant, but still have to be confirmed in efficacy studies.

Background Nasal continuous positive airway pressure support (nCPAP) is the standard of care for prematurely born infants at risk of neonatal respiratory distress syndrome (nRDS). However, nasal intermittent positive pressure ventilation (NIPPV) may be an alternative to nCPAP in babies requiring surfactant, and in conjunction with surfactant nebulization, it could theoretically reduce the need for invasive mechanical ventilation. We compared lung deposition of nebulized poractant in newborn piglets supported by nCPAP or NIPPV. Methods Twenty‐five sedated newborn piglets (1.2‐2.2 kg) received either nCPAP (3 cmH2O, n = 12) or NIPPV (3 cmH2O positive end expiratory pressure+3 cmH2O inspiratory pressure, n = 13) via custom‐made nasal prongs (FiO2 0.4, Servo‐i ventilator). Piglets received 200 mg kg−1 of technetium‐99m‐surfactant mixture continuously nebulized with a customized eFlow‐Neos investigational vibrating‐membrane nebulizer system. Blood gases were taken immediately before, during, and after nebulization. The deposition was estimated by gamma scintigraphy. Results Mean surfactant deposition in the lungs was 15.9 ± 11.9% [8.3, 23.5] (mean ± SD [95% CI]) in the nCPAP group and 21.6 ± 10% [15.6, 27.6] in the NIPPV group (P = .20). Respiratory rates were similar in both groups. Minute volume was 489 ± 203 [360, 617] in the nCPAP group and 780 ± 239 [636, 924] mL kg−1 min−1 in the NIPPV group (P = .009). Blood gases were comparable in both groups. Conclusion Irrespective of the noninvasive ventilatory support mode used, relatively high lung deposition rates of surfactant were achieved with nebulization. The amounts of deposited surfactant might suffice to elicit a pulmonary function improvement in the context of nRDS.

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Early adrenaline administration does not improve circulatory recovery during resuscitation from severe asphyxia in newborn piglets.Linnér, Rikard; Werner, Olof; Perez de Sá, Valéria; Cunha Goncalves, Doris General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. (28) AbstractAim of the study: To investigate the effects of early intravenous adrenaline administration on circulatory recovery, cerebral reoxygenation, and plasma catecholamine concentrations, after severe asphyxia-induced bradycardia and hypotension.Methods: One-day-old piglets were left in apnoea until heart rate and mean arterial pressure were less than 50 min -1 and 25 mmHg, respectively. They randomly received adrenaline, 10 µg kg -1 (n=16) or placebo (n=15) and were resuscitated with air ventilation and, when needed, closed-chest cardiac massage (CCCM). Eight not asphyxiated animals served as time controls.Results: CCCM was required in 13 piglets given adrenaline and in 13 given placebo. (ns). In the time controls, the concentrations were 0.4 (0.2-0.6) nmol l -1 of adrenaline and 1.8 (1.3-2.4) nmol l -1 of noradrenaline. (28)Conclusion: The high endogenous catecholamine levels, especially those of noradrenaline, may explain why early administered adrenaline did not significantly improve resuscitation outcome.

BACKGROUND: Earlier attempts to deliver effective lung doses of surfactant by aerosolization were unsuccessful, mostly because of technical shortcomings. We aimed at quantifying the lung deposition of poractant alfa with a new supraglottic delivery system for surfactant atomization in an experimental neonatal model. METHODS: The method involved six sedated 1-day-old piglets lying in the lateral decubitus, spontaneously breathing on nasalmask continuous positive airway pressure (nCPAP). A pharyngeal cannula housing a multi-channel air-blasting atomization catheter was placed through the mouth with its tip above the glottis entrance. In all, 200 mg kg −1 of a 99m Tc-surfactant mixture was atomized through the catheter synchronously with inspiration. Six intubated control piglets received an equal amount of intratracheally instilled 99m Tc-surfactant mixture. The percentage of the 99m Tc-surfactant mixture deposited in the lungs was estimated by scintigraphy. RESULTS: Median (range) deposition in the lungs was 40% (24-68%) after atomization and 87% (55-95%) after instillation (p < 0.001). Overall, almost 80% of the deposited surfactant was in the dependent lung. Effective atomization time (atomizer on) was 28 (17-52) min, yielding an output rate of 0.1-0.2 mL min −1 . CONCLUSIONS: Without endotracheal intubation, in spontaneously breathing newborn piglets, this new supraglottic atomizer delivery system attained a median lung deposition of 40% of the nominal dose of surfactant.

IntroductionCentral venous catheterisation is a common procedure in intensive care therapy and the use of central venous catheters is essential for treatment of many medical disorders. Although rare, central venous catheterisation is associated with mechanical complications that can be life-threatening if untreated. Real-time ultrasound guidance reduces the incidence of mechanical complications when compared with the anatomic landmark method. The purpose of this study is to determine the incidence of and potential risk factors associated with early mechanical complications of central venous catheterisation in an era where real-time ultrasound guidance has become clinical practice.Methods and analysisThis is a prospective, controlled, multicentre, observational study. All participating hospitals follow the same clinical guidelines for central venous catheterisation. Each central venous catheter insertion will be recorded in the common electronic chart system according to a recently revised template. An automated script-based search will identify all recorded central venous catheter insertion templates during the study period and relevant variables will be extracted. Outcome measures and independent variables are pre-defined in this study protocol. Multivariable and univariable logistic regression analysis will be used to determine associations and risk factors of mechanical complications.Ethics and disseminationThe Regional Ethical Review Board in Lund, Sweden has approved this study. The results will be submitted for publication in peer-reviewed medical journals and presented at national and international scientific meetings.Trial registration number NCT03782324.

<b><i>Introduction:</i></b> The ideal body position during surfactant nebulization is not known. <b><i>Objective:</i></b> The aim of this study was to determine whether body positioning during surfactant nebulization influences surfactant distribution and deposition in the lungs. <b><i>Methods:</i></b> Twenty-four 12- to 36-h-old full-term<b><i></i></b>piglets (1.3–2.2 kg) on nasal continuous positive airway pressure (nCPAP) were randomized into four groups: lateral decubitus with right or left side up, prone or supine positions (<i>n</i> = 6 each). All animals received 200 mg kg^–1 of poractant alfa mixed with 200 MBq of ^99mtechnetium-nanocolloid via a customized eFlow-Neos investigational vibrating-membrane nebulizer. Surfactant deposition (percentage of the administered dose) was measured by gamma scintigraphy. <b><i>Results:</i></b> Comparing all groups, the mean total lung surfactant deposition was significantly higher in the prone position (32.4 ± 7.7%, <i>p</i> = 0.03). The deposition in this group was higher in the right lung (21.0 ± 8.6 vs. 11.3 ± 5.7%, <i>p</i> = 0.04). When nebulization was performed in the lateral decubitus, most of the surfactant was found in the dependent lung, regardless of which side the piglet lay on (right side up 15.3 ± 1.0 vs. 3.4 ± 1.0%, <i>p</i> = 0.06, and left side up 11.2 ± 9.8 vs. 1.8 ± 0.7%, <i>p</i> = 0.04). <b><i>Conclusions:</i></b> In spontaneously breathing animals on nCPAP, the prone position yielded the highest lung dose. Higher deposition rates in the dependent lung while on lateral decubitus indicates that deposition was also influenced by gravity.

The cardioprotective effect of levosimendan on ischemic metabolism with a reduction in the myocardial lactate/pyruvate ratio, less glycerol accumulation, and better preserved glucose concentration does not seem to be prevented by beta-1 adrenergic receptor antagonism with metoprolol.