Barrington K J, Muttitt S C
Children's Health Centre, Perinatal Research Centre, University of Alberta, Edmonton, Canada.
Acta Paediatr. 1998 Feb;87(2):191-4. doi: 10.1080/08035259850157651.
The objective of the study was to determine whether administering doxapram by infusion to the very low birthweight infant, prior to extubation during the first 3 weeks of life, would increase the incidence of successful extubation. The study patients, 56 infants of less than 1251 g birthweight and less than 30 weeks' gestation, were entered in the first 3 weeks of life when lung disease had started to improve. A randomized blinded trial was performed, with infants receiving 3.5 mg kg(-1) doxapram bolus, followed by an infusion at 1 mg kg(-1) h(-1), or placebo. Weaning from positive pressure ventilation was standardized and extubation occurred after a 12 h trial of an intermittent mandatory ventilation (IMV) rate of 6 breaths min(-1), if PCO2 < 55 mmHg, pH > 7.26, and FiO2 < 0.45. Study drug was continued for 48 h postextubation, and the infants were placed on nasopharyngeal continuous positive airway pressure (CPAP) for 72 h postextubation. Extubation failure within the first 72 h after extubation was objectively defined in terms of acidosis (pH < 7.26), hypercarbia (PCO2 > 55 mmHg), excessive oxygen requirement (FiO2 > 0.8) or frequent apnoea (more than three in 12 h, or more than two requiring face mask IMV in 24 h). No difference was noted in the frequency of successful extubation between the groups. Fifteen infants in each group were successfully extubated before the 10th day of the study. In conclusion, when given in accordance with this protocol doxapram does not increase the likelihood of successful extubation in the very low birthweight infant. Increasing successful extubations in this group of infants will require other strategies.
该研究的目的是确定在出生后前3周拔管前，对极低出生体重儿静脉输注多沙普仑是否会增加成功拔管的发生率。研究对象为56例出生体重小于1251g且胎龄小于30周的婴儿，在出生后前3周肺部疾病开始改善时纳入研究。进行了一项随机双盲试验，婴儿接受3.5mg/kg多沙普仑推注，随后以1mg/kg/h的速度输注，或接受安慰剂。从正压通气撤机过程标准化，在间歇指令通气（IMV）频率为6次/分钟、持续12小时的试验后拔管，条件为PCO2<55mmHg、pH>7.26且FiO2<0.45。拔管后研究药物持续使用48小时，婴儿拔管后接受72小时的鼻咽持续气道正压通气（CPAP）治疗。拔管后72小时内拔管失败的客观定义为酸中毒（pH<7.26）、高碳酸血症（PCO2>55mmHg）、过高的氧气需求（FiO2>0.8）或频繁呼吸暂停（12小时内超过3次，或24小时内超过2次需要面罩IMV）。两组之间成功拔管的频率没有差异。每组中有15例婴儿在研究第10天前成功拔管。总之，按照该方案给药时，多沙普仑不会增加极低出生体重儿成功拔管的可能性。提高这组婴儿的成功拔管率需要其他策略。
