Walther F J, Sims M E, Siassi B, Wu P Y
J Pediatr. 1986 Nov;109(5):874-6. doi: 10.1016/s0022-3476(86)80717-x.
The cardiovascular effects of theophylline were studied in 11 clinically stable preterm infants. Theophylline was given as aminophylline using a loading dose of 6.8 mg/kg and a maintenance dose of 2 mg/kg every 8 hours intravenously. Cardiac output, stroke volume, and heart rate were measured using a combination of pulsed Doppler ultrasound and M-mode echocardiography. Compared with day 0, an increase was found in both cardiac output (P less than 0.01) and stroke volume (P less than 0.02) on days 1, 2, and 3. By day 7, stroke volume was comparable to pretreatment values, whereas cardiac output was still increased. Heart rate was augmented significantly (P less than 0.01) throughout the treatment period. Mean arterial blood pressure did not change. All but one of the neonates had serum theophylline concentrations between 6 and 13 mg/L. We conclude that both inotropic and chronotropic effects are evident during the first days of theophylline therapy. The metabolic cost of the increased cardiac output in the preterm infant with theophylline therapy deserves further attention.
在11名临床状况稳定的早产婴儿中研究了茶碱的心血管效应。以氨茶碱的形式给予茶碱，静脉注射的负荷剂量为6.8毫克/千克，维持剂量为每8小时2毫克/千克。使用脉冲多普勒超声和M型超声心动图相结合的方法测量心输出量、每搏输出量和心率。与第0天相比，在第1、2和3天，心输出量（P<0.01）和每搏输出量（P<0.02）均有所增加。到第7天，每搏输出量与治疗前值相当，而心输出量仍增加。在整个治疗期间，心率显著增加（P<0.01）。平均动脉血压没有变化。除一名新生儿外，所有新生儿的血清茶碱浓度在6至13毫克/升之间。我们得出结论，在茶碱治疗的最初几天，正性肌力和变时性效应均很明显。茶碱治疗的早产婴儿心输出量增加的代谢代价值得进一步关注。
