Nadkarni S, Hay A W, Faye S, Congdon P J
Department of Chemical Pathology, Old Medical School, Leeds General Infirmary, UK.
Ann Clin Biochem. 1988 Jul;25 ( Pt 4):408-10. doi: 10.1177/000456328802500415.
Plasma theophylline and caffeine levels were measured in neonates receiving aminophylline for apnoea. Significant levels of caffeine were present in neonates with high plasma theophylline levels and particularly in those children who had been on theophylline for 6 days, or more. Caffeine levels in plasma decreased slowly compared to theophylline. Tachycardia did not occur in any infants even at theophylline values greater than 20 mg/L. For theophylline concentrations above 10 mg/L there was no relationship between heart rate and drug level. Heart rate alone cannot be used to predict toxic drug levels, and high drug levels will not necessarily cause tachycardia.
对接受氨茶碱治疗呼吸暂停的新生儿进行了血浆茶碱和咖啡因水平的测定。血浆茶碱水平高的新生儿，尤其是那些接受茶碱治疗6天及以上的儿童，体内存在显著水平的咖啡因。与茶碱相比，血浆中的咖啡因水平下降缓慢。即使茶碱值大于20mg/L，也没有婴儿出现心动过速。对于茶碱浓度高于10mg/L的情况，心率与药物水平之间没有关系。不能仅通过心率来预测药物中毒水平，高药物水平不一定会导致心动过速。
