DOES NEBULIZED DEXAMETHASONE IMPROVE PULMONARY FUNCTION IN NEONATES?

这项随机、双盲、安慰剂对照研究的具体目的是：1)测量吸入性地塞米松的相对全身利用度，并评估吸入性地塞米松一个疗程期间全身吸收的一致性；2)评估和比较接受7天吸入性地塞米松或静脉注射地塞米松的呼吸机依赖早产儿的呼吸机支持(通气率)、最大吸气压和吸入氧气分数的变化；3)确定全身药物暴露与静脉和吸入地塞米松后呼吸机参数的改善和不良反应之间的关系。已有20名患者参加了这项研究，但结果尚未分析。一个重要的治疗目标是确定正在评估的一种或其他形式的治疗是否可以通过将呼吸机引起的气压创伤和氧毒性降至最低来降低支气管肺发育不良的严重性和并发症。以前的研究表明，静脉注射地塞米松的益处不是盲目的，因此治疗组和未治疗组的管理可能并不相同。尽管雾化类固醇在减少全身类固醇暴露方面有明显的优势，但在新生儿中进行的研究并未比较吸入类固醇的疗效、不良反应或全身吸收，并将结果与更常用的静脉注射地塞米松进行比较。如果吸入类固醇可以改善肺功能，与声称静脉注射类固醇的结果相当，风险-收益比显然有利于吸入治疗。该议定书将解决早产儿护理中的这一非常重要的问题。

The specific aims of this randomized, double-blinded, placebo-controlled study are to: 1) measure the relative systemic availability of inhaled dexamethasone and assess the consistency of systemic absorption during a course of inhaled dexamethasone; 2) evaluate and compare changes in ventilatory support (rate of ventilation), peak inspiratory pressure, and fractional inspired oxygen in ventilator-dependent premature neonates receiving a 7-day course of inhaled dexamethasone or intravenous dexamethasone and; 3) define relationships between systemic drug exposure and improvements in ventilatory parameters and adverse effects after both intravenous and inhaled dexamethasone. Twenty patients have been enrolled on this study, but results have not yet been analyzed. An important treatment objective is to determine if one or the other forms of therapy being evaluated will reduce the severity and complications of bronchopulmonary dysplasia by minimizing ventilator-induced barotrauma and oxygen toxicity. Previous studies suggesting benefit from intravenous dexamethasone infusions were not blinded, and thus management may not have been equal between treated and untreated groups. Despite the apparent advantage of aerosolized steroids in minimizing systemic steroid exposure, studies conducted in neonates have not compared efficacy, adverse effects, or systemic absorption of inhaled steroids, and compared the outcome to more commonly administered intravenous dexamethasone. If inhaled steroids result in improved pulmonary function comparable to that claimed for intravenous steroids, the risk-benefit ratio would clearly favor treatment by inhalation. This protocol will address this very important issue in the care of premature neonates.