Eisa Lara, Passi Yuvesh, Lerman Jerrold, Raczka Michelle, Heard Christopher
Department of Anesthesiology, Women and Children's Hospital of Buffalo, Buffalo, New York, USA.
Department of Anesthesiology, Women and Children's Hospital of Buffalo, Buffalo, New York, USA University of Rochester, Rochester, New York, USA.
Arch Dis Child. 2015 Jul;100(7):684-8. doi: 10.1136/archdischild-2014-307868. Epub 2015 Mar 11.
To determine the heart rate response to atropine (<0.1 mg) in anaesthetised young infants.
Prospective, observational and controlled.
Elective surgery.
Sixty unpremedicated healthy infants less than 15 kg were enrolled. Standard monitoring was applied. Anaesthesia was induced by mask with nitrous oxide (66%) and oxygen (33%) followed by sevoflurane (8%).
Intravenous (IV) atropine (5 µg/kg) was flushed into a fast flowing IV. The ECG was recorded continuously from 30 s before the atropine until 5 min afterwards.
The incidence of bradycardia and arrhythmias was determined from the ECGs by a blinded observer.
The median (IQR) age was 6.5 (4-12) months and the mean (95% CI) weight was 8.6 (8.1 to 9.1) kg. The mean (95% CI) dose of atropine was 40.9 (37.3 to 44) µg. Bradycardia did not occur. Two infants developed premature atrial contractions and one developed a premature ventricular contraction. When compared with baseline values, heart rate increased by 7% 30 s after atropine, 14% 1 min after atropine and 25% 5 min after atropine. Twenty-nine infants (48%) experienced tachycardia (>20% above baseline rate) after atropine lasting 222.7 s (range 27.9-286). The change in heart rate 5 min after atropine was inversely related to the baseline heart rate.
The upper 95% CI for the occurrence of bradycardia in the entire population of infants based on a zero incidence in this study is 5%. These results rebut the notion that atropine <0.1 mg IV causes bradycardia in young infants.
ClinicalTrials.gov #NCT01819064.
确定麻醉状态下的幼儿对阿托品（<0.1毫克）的心率反应。
前瞻性、观察性且有对照。
择期手术。
纳入60名未使用术前药的健康婴儿，体重小于15千克。采用标准监测。通过面罩吸入氧化亚氮（66%）和氧气（33%）诱导麻醉，随后吸入七氟醚（8%）。
将静脉注射（IV）阿托品（5微克/千克）注入快速流动的静脉输液管。在注射阿托品前30秒至注射后5分钟持续记录心电图。
由一名不知情的观察者根据心电图确定心动过缓和心律失常的发生率。
年龄中位数（四分位间距）为6.5（4 - 12）个月，平均（95%置信区间）体重为8.6（8.1至9.1）千克。阿托品的平均（95%置信区间）剂量为40.9（37.3至44）微克。未发生心动过缓。两名婴儿出现房性早搏，一名出现室性早搏。与基线值相比，注射阿托品后30秒心率增加7%，1分钟后增加14%，5分钟后增加25%。29名婴儿（48%）在注射阿托品后出现心动过速（高于基线心率20%以上），持续222.7秒（范围27.9 - 286秒）。注射阿托品后5分钟时心率变化与基线心率呈负相关。
基于本研究中零发生率，整个婴儿群体心动过缓发生率的95%置信区间上限为5%。这些结果反驳了静脉注射<0.1毫克阿托品会导致幼儿心动过缓的观点。
ClinicalTrials.gov #NCT01819064。
