Department of Pharmacy, Hutzel Women's Hospital, Detroit, MI, USA.
Acta Paediatr. 2012 Apr;101(4):e147-50. doi: 10.1111/j.1651-2227.2011.02578.x. Epub 2012 Jan 10.
To evaluate fluctuations in anti-Xa concentrations in infants treated with enoxaparin for thrombosis and describe clinical outcomes.
A retrospective chart review was performed on infants treated with enoxaparin in the Neonatal Intensive Care Unit, and data on enoxaparin doses, anti-Xa concentrations, clinical characteristics and outcomes were abstracted.
Our cohort (n = 26) had a median gestation of 36 (range, 23-41) weeks, birthweight of 2522 (510-3912) grams and 5-min Apgar score of 8(4-9). Fifteen (57.7%) infants were males. Thromboses was diagnosed at a median age of 22 (range, 1-97) days; enoxaparin was initiated at 27.5 (range, 4-98) days at a mean (SD) dose of 1.4 (0.3) mg/kg every 12 h. Therapeutic anti-Xa concentrations (0.5-1 U/mL) were achieved at a mean (SD) dose of 2.1 (0.6) mg/kg at 12.5 (12.2) days of treatment. Of the 143 anti-Xa concentrations, 39 (27%) were within the therapeutic range. During maintenance therapy following initial therapeutic anti-Xa concentration, 40% concentrations were therapeutic. Minor bleeding was noted in four infants and intracranial bleed in one infant; four infants died. During treatment, thrombocytopenia, renal and hepatic impairment during treatment were noted in 7, 2 and 4 infants, respectively. Clot resolution was observed in 21 (81%) infants.
Anti-Xa concentrations fluctuate during maintenance enoxaparin therapy, with therapeutic levels being achieved only sporadically in young infants. Despite this, enoxaparin appears efficacious in thrombosis resolution. Further studies on the impact of stringent control of concentrations on outcomes in this population are warranted.
评估接受依诺肝素治疗的血栓患儿的抗 Xa 浓度波动情况，并描述临床结局。
对新生儿重症监护病房接受依诺肝素治疗的患儿进行回顾性病历分析，提取依诺肝素剂量、抗 Xa 浓度、临床特征和结局数据。
本队列（n=26）的中位胎龄为 36 周（范围 23-41 周），出生体重为 2522 克（范围 510-3912 克），5 分钟 Apgar 评分为 8 分（范围 4-9 分）。15 例（57.7%）患儿为男性。血栓形成的中位诊断年龄为 22 天（范围 1-97 天）；依诺肝素于 27.5 天（范围 4-98 天）开始，平均（SD）剂量为 1.4（0.3）mg/kg，每 12 小时 1 次。在治疗的第 12.5（12.2）天时，平均（SD）剂量为 2.1（0.6）mg/kg 时达到治疗性抗 Xa 浓度（0.5-1 U/mL）。在 143 次抗 Xa 浓度中，39 次（27%）在治疗范围内。在初始治疗性抗 Xa 浓度后维持治疗期间，40%的浓度为治疗性浓度。4 例患儿出现轻微出血，1 例患儿出现颅内出血，4 例患儿死亡。在治疗期间，分别有 7、2 和 4 例患儿出现血小板减少、肾功能和肝功能损害。21 例（81%）患儿的血栓得到缓解。
在依诺肝素维持治疗期间，抗 Xa 浓度波动，而小婴儿仅偶尔达到治疗水平。尽管如此，依诺肝素似乎对血栓溶解有效。有必要进一步研究在该人群中严格控制浓度对结局的影响。
