Asunto(s)

RESUMEN

Extremely preterm infants often develop chronic lung disease (CLD) characterized by heterogeneous aeration; poorly supported, floppy airways; and air trapping. High-frequency jet ventilation (HFJV) with high end-expiratory pressure (optimal lung volume strategy [OLVS]) may improve airway patency, lead to better gas distribution, improve gas exchange, and facilitate extubation. In a pilot trial, this study sought to explore the effect of HFJV on oxygenation, ventilation, and ease of extubation in preterm infants with evolving CLD and refractory respiratory failure (RRF). From September 2002 to October 2004, 12 episodes of RRF developed in 10 ventilated extremely immature infants with evolving CLD (10 on conventional and two on high-frequency oscillation). Chorioamnionitis was confirmed in all infants, patent ductus arteriosus was ligated in five patients, and UREAPLASMA UREALYTICUM was cultured from trachea in four patients. HFJV with OLVS was initiated when oxygenation index (OI) > 10 or exhaled tidal volume (V TE) >or= 7 mL/kg were required to maintain partial pressure of carbon dioxide, arterial (Pa CO2) < 60 mm Hg. Inspiratory time (0.02/s) and frequency (310 to 420/min) were set initially with adjustment of pressure amplitude to keep Pa CO2 between 45 and 55 mm Hg. Ventilatory stabilization and weaning from mechanical ventilation with extubation to nasal continuous positive airway pressure (CPAP) were the goals of this approach. Gas exchange data were analyzed by Analysis of variance for repeated measures. Ten patients on 11 occasions of RRF were extubated to nasal CPAP successfully in a median of 15.5 days. Nine of 10 patients survived (one died of pentalogy of Cantrell), all required supplemental O2 at 36 weeks. Pa CO2 decreased within 1 hour after the initiation of HFJV, and OI decreased by 24 hours. Both remained significantly lower until successful extubation ( P < 0.02). Compared with conventional ventilation or high-frequency oscillatory ventilation, HFJV used with OLVS appears to improve gas exchange and may facilitate weaning from mechanical ventilation (MV) in extremely immature infants with evolving CLD. These encouraging pilot data need to be confirmed in a larger clinical trial.

Asunto(s)

Asunto(s)

RESUMEN

OBJECTIVE: To compare the effectiveness and safety of very early high-frequency oscillatory ventilation (HFOV) with conventional mechanical ventilation (CMV) in treatment of the respiratory distress syndrome (RDS) and to evaluate their impact on the incidence of chronic pulmonary disease and early and late morbidity of very low-birthweight neonates. DESIGN: A prospective randomized clinical trial. SETTING: Tertiary neonatal intensive care unit in the Perinatology Center in Prague. PATIENTS: 43 premature newborns, delivered in the Department of Obstetrics in the Perinatology Center, were randomly divided into two groups (HFOV and CMV) immediately after delivery; 2 patients in each group died, 2 fulfilled crossover criteria from CMV to HFOV, and 2 were excluded because of congenital malformations. Nineteen patients treated with HFOV were therefore compared with 18 infants in the CMV group. METHODS: The two contrasting modes of ventilation were introduced immediately after intubation. Maintenance of optimal lung volume in HFOV to optimize oxygenation and the therapeutic administration of surfactant after fulfilling defined criteria are important points of the strategy and design of the study. MEASUREMENTS AND MAIN RESULTS: Except for a higher proportion of males in the HFOV group (p<0.02), the basic clinical characteristics (gestational age, birthweight, Apgar score at 5 min, umbilical arterial pH), the two groups were similar. In the acute stage of RDS, infants treated with HFOV had higher proximal airway distending pressure with HFOV for 6 h after delivery (p<0.05). For a period of 12 h after delivery lower values for the alveolar-arterial oxygen difference (p<0.03) were noted. The number of patients who did not require surfactant treatment was higher in the HFOV group (11 vs. 1, p<0.001). In the HFOV group the authors found a lower roentgenographic score at 30 days of age (p<0.03) and a lower clinical score in the 36th postconceptional week (p<0.05), using these two scoring systems for assessing chronic lung disease according to Toce scale. The incidence of pneumothorax, pulmonary interstitial emphysema, intraventricular hemorrhage and retinopathy of prematurity in both groups was the same. CONCLUSIONS: HFOV, when applied early and when the clinical strategy of maintenance of optimal lung volume is used, improves oxygenation in the acute stage of RDS, reduces the need of surfactant administration, and can decrease the injury to lung tissue even in extremely immature newborns to whom surfactant is administered therapeutically.

Asunto(s)

RESUMEN

UNLABELLED: Extremely immature neonates are threatened during the first days after delivery by many conditions which are due to incomplete development.--A key role is played during the first days of extrauterine life by the incidence and degree of the respiratory distress syndrome (RDS). Its incidence in neonates born before the completed 32nd week of gestation is very common. Causal treatment of RDS is not known. To overcome it the neonatologist must use in the majority of infants invasive techniques of controlled ventilation which are associated with the risk of further complications such as barotrauma, retinopathy and later the development of bronchopulmonary dysplasia. Attempts to influence intrauterine maturation of the lungs were started in the fifties. As a routine procedure nowadays corticoids are administered antenatally. Their limited effect divert the attention of perinatologists to other substances which could enhance maturation of pulmonary tissue. In human medicine ambroxol was introduced, in animals opiates are tested as well as beta-mimetics, aminophylline. The greatest hopes were aroused by trials with the use of T-hormones. T-hormones have a maturating regulating function in the foetal organism. They have an affinity for pneumocytes and in animal experiments they have a positive effect on surfactant formation. Moreover they act synergically when combined with corticoids. OBJECTIVE OF STUDY: a) to evaluate the safety of the method from the aspect of undesirable side-effects of hormone administration to the mother b) evaluation of hormone levels: TSH, total T4, total T3, TRH and prolactin in maternal serum.

Asunto(s)

RESUMEN

The authors submit suggestions for the differential diagnostic procedure in dilatation of the calico-pelvic system in children involving consecutive application of non-invasive methods to methods pretentious for the patient. In the second part they present a review of recent findings regarding visualization techniques of the hollow renal system.

Asunto(s)