Simons F E, Roberts J R, Gu X, Simons K J
Department of Pediatrics and Child Health, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.
J Allergy Clin Immunol. 1998 Jan;101(1 Pt 1):33-7. doi: 10.1016/S0091-6749(98)70190-3.
Prompt injection of epinephrine is the cornerstone of systemic anaphylaxis treatment. The rate of epinephrine absorption has not been reported previously in allergic children.
Our objective was to study the clinical pharmacology of epinephrine in this population.
We performed a prospective, randomized, blinded, parallel-group study in 17 children with a history of anaphylaxis to food, Hymenoptera venom, or other substances. We injected 0.01 ml/kg epinephrine solution (maximum 0.3 ml [0.3 mg]) subcutaneously, or 0.3 mg epinephrine intramuscularly from an autoinjector. Plasma epinephrine concentrations, heart rate, blood pressure, and adverse effects were monitored.
In nine children who received epinephrine subcutaneously, the mean maximum plasma epinephrine concentration (+/- SEM) was 1802 +/- 214 pg/ml, achieved at a mean time of 34 +/- 14 minutes (range, 5 to 120 minutes). Only two of the nine children achieved maximum plasma concentrations by 5 minutes. In eight children who received epinephrine intramuscularly, the mean maximum plasma concentration was 2136 +/- 351 pg/ml, achieved at a mean time of 8 +/- 2 minutes, which was significantly faster than the mean time at which maximum plasma concentrations were achieved after subcutaneous epinephrine injection (p < 0.05). Six of the eight children achieved maximum plasma concentrations by 5 minutes. The terminal elimination half-life was 43 +/- 15 minutes. No serious adverse effects were noted in any child.
In children, recommendations for subcutaneous epinephrine injection are based on anecdotal experience, and should be reevaluated in view of our finding of delayed epinephrine absorption when this route is used. This delay might have important clinical implications during an episode of systemic anaphylaxis. The intramuscular route of injection is preferable.
及时注射肾上腺素是全身性过敏反应治疗的基石。此前尚未有关于过敏儿童肾上腺素吸收速率的报道。
我们的目的是研究该人群中肾上腺素的临床药理学。
我们对17名有食物、膜翅目毒液或其他物质过敏史的儿童进行了一项前瞻性、随机、双盲、平行组研究。我们皮下注射0.01 ml/kg肾上腺素溶液（最大0.3 ml [0.3 mg]），或使用自动注射器肌肉注射0.3 mg肾上腺素。监测血浆肾上腺素浓度、心率、血压及不良反应。
9名接受皮下注射肾上腺素的儿童中，血浆肾上腺素平均最大浓度（±标准误）为1802±214 pg/ml，平均在34±14分钟（范围5至120分钟）时达到。9名儿童中只有2名在5分钟时达到最大血浆浓度。8名接受肌肉注射肾上腺素的儿童中，血浆平均最大浓度为2136±351 pg/ml，平均在8±2分钟时达到，明显快于皮下注射肾上腺素后达到最大血浆浓度的平均时间（p<0.05）。8名儿童中有6名在5分钟时达到最大血浆浓度。终末消除半衰期为43±15分钟。所有儿童均未出现严重不良反应。
在儿童中，皮下注射肾上腺素的建议基于轶事经验，鉴于我们发现使用该途径时肾上腺素吸收延迟，应重新评估。这种延迟在全身性过敏反应发作期间可能具有重要的临床意义。肌肉注射途径更可取。
