Ingemarsson I, Arulkumaran S, Ratnam S S
Am J Obstet Gynecol. 1985 Dec 15;153(8):859-65. doi: 10.1016/0002-9378(85)90690-8.
Thirty-three patients with prolonged fetal bradycardia (fetal heart rate baseline less than 100 bpm for a minimum of 3 minutes or less than 80 bpm for at least 2 minutes) in labor were studied. They were treated with a bolus injection of terbutaline if the bradycardia persisted at less than 80 bpm for 2 minutes and other efforts to improve the fetal heart rate (oxygen, positional changes) had failed. After the bolus injection a scalp blood pH (or a cord arterial pH in abdominal deliveries) was obtained within 30 minutes. Fetal acidosis was common if the bradycardia lasted 10 minutes or more, particularly if the rate was less than 80 bpm with a flat baseline for 4 minutes or more. The fetal heart rate improved after injection in 30 cases; 23 patients had vaginal delivery of infants in good condition. Ten underwent cesarean section: three for no improvement in fetal heart rate, two for cord prolapse, four for later ominous fetal heart rate, and one for failure to progress. These results suggest that tocolysis in selected cases can be of benefit for the fetus with prolonged bradycardia. In cases with an ominous fetal heart rate pattern preceding the bradycardia and in abruptio placentae immediate operative intervention without delay is probably better. Administration of terbutaline should be regarded as a temporary measure until it is apparent that the fetal heart rate has recovered. Preparation for emergency delivery should be made while a recovery is awaited.
对33例分娩时出现胎儿心动过缓延长（胎儿心率基线低于100次/分钟至少3分钟或低于80次/分钟至少2分钟）的患者进行了研究。如果心动过缓持续低于80次/分钟达2分钟且其他改善胎儿心率的措施（吸氧、改变体位）无效，则给予患者静脉推注特布他林。推注后30分钟内获取头皮血pH值（或剖宫产时的脐动脉pH值）。如果心动过缓持续10分钟或更长时间，尤其是心率低于80次/分钟且基线平坦达4分钟或更长时间，则胎儿酸中毒很常见。注射后30例患者的胎儿心率有所改善；23例患者经阴道分娩出状况良好的婴儿。10例患者接受了剖宫产：3例因胎儿心率无改善，2例因脐带脱垂，4例因随后出现不祥的胎儿心率，1例因产程无进展。这些结果表明，在某些情况下，宫缩抑制剂对延长心动过缓的胎儿可能有益。对于心动过缓之前出现不祥胎儿心率模式的病例以及胎盘早剥，立即进行手术干预可能更好。在胎儿心率明显恢复之前，特布他林的使用应被视为一种临时措施。在等待恢复的同时应做好紧急分娩的准备。
