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Objective: To evaluate the effects of 24 h partial liquid ventilation (PLV) with and without surfactant (S) treatment on gas exchange and lung injury in a newborn animal model of S deficiency., Design: A prospective, controlled, in vivo animal laboratory study., Setting: Research laboratory in a university setting., Subjects: Twenty-four pathogen-free, male piglets (mean weight 1.9 kg, age 1-3 days)., Interventions: The animals were randomised in four groups: PLV with FC-77 combined with conventional ventilation (PLV/CV) versus S + PLV/CV and PLV combined with high frequency oscillatory ventilation (PLV/HFOV) versus S + PLV/HFOV. The piglets were anaesthetised, intubated and instrumented with vascular catheters. Thirty minutes after lung injury had been induced with repeated saline lavage, S animals received natural S. Thirty minutes after surfactant substitution PLV with FC-77 was started. The oxygenation index (OI), PaO(2)/FIO(2) ratio, PaCO(2) and the ventilatory efficacy index were determined before and during PLV. After 24 h the lungs were removed for histopathological examination., Measurements and Main Results: Within 60 min after the initiation of PLV, all animals demonstrated improvements of the OI and PaO(2)/FIO(2) ratio compared to the values after lung injury. However, at 18 and 24 h of PLV, the OI and PaO(2)/FIO(2) ratio were significantly worse in the S + PLV/CV and S + PLV/HFOV groups compared to the groups without S. PaCO(2) was higher at 18 and 24 h when S was used in PLV/HFOV (p < 0.05). A semi-quantitative lung injury score revealed most severe lung damage in the S + PLV/HFOV group. CONCLUSIONS++: The combination of S and PLV with FC-77 led to an impaired gas exchange and did not further protect the animal from lung injury.

The aim of this randomized, double-blind pilot study was to evaluate the short-term efficacy of early inhalation therapy with budesonide in ventilator-dependent preterm infants. The primary outcome variable was the duration of artificial ventilation; secondary outcome variables were the need for supplemental oxygen and the release of several inflammatory mediators in the tracheobronchial aspirate fluid. The infants of the budesonide group could not be weaned earlier from the ventilator. The ventilatory parameters on day 14 of life and the need for supplemental oxygen were similar in both groups. The release of inflammatory mediators was not reduced in the budesonide group. No adverse side effects were observed in either group. In conclusion, aerosolized budesonide failed to demonstrate significant short-term pulmonary improvement in ventilator-dependent preterm infants.

Two different ventilation techniques were compared in a seven-centre, randomised trial with 181 preterm infants up to and including 32 completed weeks gestational age, who needed mechanical ventilation because of lung disease of any type. Technique A used a constant rate (60 cycles/min), inspiratory time (IT) (0.33s) and inspiratory: expiratory ratio (I:E) (1:2). The tidal and minute volume was only changed by varying peak inspiratory pressure until weaning via continuous positive airway pressure. Technique B used a lower rate (30 cycles/min) with longer IT (1.0 s). The I:E ratio could be changed from 1:1 to 2:1 in case of hypoxaemia. Chest X-rays taken at fixed intervals were evaluated by a paediatric radiologist and a neonatologist unaware of the type of ventilation used in the patients. A reduction of at least 20% in extra-alveolar air leakage (EAL) or death prior to EAL was supposed in infants ventilated by method A. A sequential design was used to test this hypothesis. The null hypothesis was rejected (P = 0.05) when the 22nd untied pair was completed. The largest reduction in EAL (-55%) was observed in the subgroup 31-32 weeks of gestation and none in the most immature group (< 28 weeks). We conclude that in preterm infants requiring mechanical ventilation for any reason of lung insufficiency, ventilation at 60 cycles/min and short IT (0.33 s) significantly reduces EAL or prior death compared with 30 cycles/min and a longer IT of 1 s. We speculate that a further increase in rate and reduction of IT would also lower the risk of barotrauma in the most immature and susceptible infants.

Successive manifestations of acute air leak phenomenona are reported in a ventilated premature infant with aspiration of amniotic fluid. The increasingly reported incidence of pulmonary interstitial emphysema is emphasized. After its first occurrence there is a serious need for careful clinical and radiological observation because of the great risk of further complications.