Kost G J, Vu H T, Lee J H, Bourgeois P, Kiechle F L, Martin C, Miller S S, Okorodudu A O, Podczasy J J, Webster R, Whitlow K J
University of California, Davis 95616, USA.
Crit Care Med. 1998 Mar;26(3):581-90. doi: 10.1097/00003246-199803000-00036.
Existing handheld glucose meters are glucose oxidase (GO)-based. Oxygen side reactions can introduce oxygen dependency, increase potential error, and limit clinical use. Our primary objectives were to: a) introduce a new glucose dehydrogenase (GD)-based electrochemical biosensor for point-of-care testing; b) determine the oxygen-sensitivity of GO- and GD-based electrochemical biosensor test strips; and c) evaluate the clinical performance of the new GD-based glucose meter system in critical care/hospital/ambulatory patients.
Multicenter study sites compared glucose levels determined with GD-based biosensors to glucose levels determined in whole blood with a perchloric acid deproteinization hexokinase reference method. One site also studied GO-based biosensors and venous plasma glucose measured with a chemistry analyzer. Biosensor test strips were used with a handheld glucose monitoring system. Bench and clinical oxygen sensitivity, hematocrit effect, and precision were evaluated.
The study was performed at eight U.S. medical centers and one Canadian medical center.
There were 1,248 patients.
The GO-based biosensor was oxygen-sensitive. The new GD-based biosensor was oxygen-insensitive. GD-based biosensor performance was acceptable: 2,104 (96.1%) of 2,189 glucose meter measurements were within +/-15 mg/dL (+/-0.83 mmol/L) for glucose levels of < or = 100 mg/dL (< or = 5.55 mmol/L) or within +/-15% for glucose levels of > 100 mg/dL, compared with the whole-blood reference method results. With the GD-based biosensor, the percentages of glucose measurements that were not within the error tolerance were comparable for different specimen types and clinical groups. Bracket predictive values were acceptable for glucose levels used in therapeutic management.
The performance of GD-based, oxygen-insensitive, handheld glucose testing was technically suitable for arterial specimens in critical care patients, cord blood and heelstick specimens in neonates, and capillary and venous specimens in other patients. Multicenter findings benchmark the performance of bedside glucose testing devices. With the new +/-15 mg/dL --> 100 mg/dL --> +/-15% accuracy criterion, point-of-care systems for handheld glucose testing should score 95% (or better), as compared with the recommended reference method. Physiologic changes, preanalytical factors, confounding variables, and treatment goals must be taken into consideration when interpreting glucose results, especially in critically ill patients, for whom arterial blood glucose measurements will reflect systemic glucose levels.
现有的手持式血糖仪基于葡萄糖氧化酶（GO）。氧的副反应会导致对氧的依赖性，增加潜在误差，并限制临床应用。我们的主要目标是：a）引入一种基于葡萄糖脱氢酶（GD）的新型电化学生物传感器用于即时检测；b）确定基于GO和GD的电化学生物传感器测试条的氧敏感性；c）评估新型基于GD的血糖仪系统在重症监护/医院/门诊患者中的临床性能。
多中心研究地点将基于GD的生物传感器测定的葡萄糖水平与采用高氯酸脱蛋白己糖激酶参考方法测定的全血葡萄糖水平进行比较。一个地点还研究了基于GO的生物传感器以及用化学分析仪测定的静脉血浆葡萄糖。生物传感器测试条与手持式葡萄糖监测系统一起使用。评估了实验台和临床的氧敏感性、血细胞比容效应及精密度。
该研究在美国的八个医疗中心和一个加拿大医疗中心进行。
共有1248例患者。
基于GO的生物传感器对氧敏感。新型基于GD的生物传感器对氧不敏感。基于GD的生物传感器性能可接受：与全血参考方法结果相比，对于葡萄糖水平≤100mg/dL（≤5.55mmol/L），2189次血糖仪测量中有2104次（96.1%）在±15mg/dL（±0.83mmol/L）范围内；对于葡萄糖水平＞100mg/dL，在±15%范围内。使用基于GD的生物传感器时，不同标本类型和临床组超出误差容许范围的葡萄糖测量百分比相当。对于治疗管理中使用的葡萄糖水平，区间预测值可接受。
基于GD的、对氧不敏感的手持式葡萄糖检测性能在技术上适用于重症监护患者的动脉标本、新生儿的脐血和足跟血标本以及其他患者的毛细血管和静脉标本。多中心研究结果为床边葡萄糖检测设备的性能设定了基准。采用新的±15mg/dL→100mg/dL→±15%准确性标准时，与推荐的参考方法相比，手持式葡萄糖检测的即时检测系统得分应达到95%（或更高）。在解释葡萄糖结果时，必须考虑生理变化、分析前因素、混杂变量和治疗目标，尤其是在重症患者中，动脉血糖测量将反映全身葡萄糖水平。
