Schoenenberger R A, Tanasijevic M J, Jha A, Bates D W
Division of Clinical Epidemiology, Brigham and Women's Hospital, Boston, MA 02115, USA.
JAMA. 1995;274(20):1622-6.
To develop explicit, reliable appropriateness criteria for antiepileptic drug level monitoring and to assess the appropriateness of monitoring in one tertiary care institution.
Appropriateness criteria derived from the literature and through expert opinion were used to evaluate a stratified random sample of antiepileptic drug level determinations obtained from chart review.
Tertiary care center performing more than 10,000 antiepileptic drug level determinations per year.
A total of 330 inpatients in whom antiepileptic drug levels were measured a total of 855 times.
Drug levels were assessed at least 200 times for each of four antiepileptic drugs (phenytoin, carbamazepine, phenobarbital, and valproic acid).
The proportion of antiepileptic drug levels with an appropriate indication and, of those, the proportion sampled appropriately.
Overall, 27% (95% confidence interval, 24% to 30%) of levels had an appropriate indication. Interrater agreement for appropriateness was substantial (kappa = 0.61). There was no significant difference in the appropriateness rate among the four drugs (range, 25% to 29%). Of the 624 antiepileptic drug level determinations considered inappropriate (73%), only four (0.6%) were more than 20% higher than the upper limit of normal, and none of the four patients had clinical signs of drug toxicity. A median of six levels (range, one through 69) was determined per patient, and the median interval between level determinations was 24 hours. Of the 27% of level determinations with an appropriate indication, 51% were sampled correctly, resulting in an overall appropriateness rate of 14%.
Only 27% of antiepileptic drug level determinations had an appropriate indication, and half of these were not sampled correctly. Routine daily monitoring without pharmacological justification accounted for most of the inappropriate drug level determinations. Efforts to decrease inappropriate monitoring may result in substantial cost reductions without missing important clinical results.
制定明确、可靠的抗癫痫药物血药浓度监测适宜性标准，并评估一家三级医疗机构中监测的适宜性。
采用从文献及专家意见得出的适宜性标准，对通过病历审查获得的抗癫痫药物血药浓度测定分层随机样本进行评估。
每年进行超过10000次抗癫痫药物血药浓度测定的三级医疗机构。
共330例住院患者，抗癫痫药物血药浓度共测定855次。
对四种抗癫痫药物（苯妥英、卡马西平、苯巴比妥和丙戊酸）每种至少测定200次血药浓度。
有适当指征的抗癫痫药物血药浓度比例，以及其中采样适当的比例。
总体而言，27%（95%置信区间为24%至30%）的血药浓度有适当指征。评定者间在适宜性方面的一致性较高（kappa = 0.61）。四种药物的适宜率无显著差异（范围为25%至29%）。在624次被认为不适宜的抗癫痫药物血药浓度测定中（73%），只有4次（0.6%）高于正常上限20%以上，且这4例患者均无药物毒性的临床体征。每位患者血药浓度测定的中位数为6次（范围为1至69次），血药浓度测定之间的间隔中位数为24小时。在有适当指征的27%的血药浓度测定中，51%采样正确，总体适宜率为14%。
仅27%的抗癫痫药物血药浓度测定有适当指征，其中一半采样不正确。无药理学依据的常规每日监测占大多数不适宜的血药浓度测定。减少不适宜监测的努力可能会大幅降低成本，且不会遗漏重要的临床结果。
