Jordan Melanie A, Choksi Dimpa, Lombard Kelsey, Patton Lynn R
Midwestern University, Glendale, AZ, USA.
Medical City, McKinney, TX, USA.
Hosp Pharm. 2021 Jun;56(3):165-171. doi: 10.1177/0018578719873869. Epub 2019 Sep 6.
Syringes are commonly used in pharmacy compounding for the measurement of small volumes, especially in the preparation of sterile products for injection and infusion. However, there are no current official guidelines for the proper use of syringes in measuring small volumes. The purpose of this project was to determine the accuracy and precision of commercially available syringes in measuring small volumes during sterile product preparation to make recommendations for syringe size selection. To assess precision and accuracy of syringes, 3 separate investigators measured 5%, 10%, or 20% (n = 30 each) of the volume of a 1-, 3-, 5-, 10-, or 20-mL syringe with an attached 18G, 1½" needle by drawing sterile water for injection from a vial. Delivered volumes were measured gravimetrically using an electronic balance and converted to volume using the specific gravity of water (1.0). Accuracy is represented as the mean and standard deviation, while precision is represented as percent relative standard deviation. Differences were assessed using a 1-way analysis of variance with Bonferroni adjustments and significance set at < .05. Precision and accuracy were highly variable and often significantly ( < .05) different compared to the theoretical volume delivered both within and between investigators. An increased likelihood of unacceptable error (>5%) was observed when less than 20% of the labeled capacity of a syringe was measured. Mean percent error ranged from 1.4% to 18.6%, despite manufacturer specification of ±5% accuracy, suggesting proper technique as a major factor in small-volume measurements. In addition to proper, validated training of syringe users, we recommend that users measure no less than 20% of the indicated volume of the syringe while choosing syringes as close as possible to the desired measurement. When possible, very small volumes should be diluted to meet the minimum volume of the smallest syringe available. Implementation of these recommendations will improve accurate dosing and, ultimately, patient safety.
注射器在药房调配中常用于测量小体积液体，尤其是在制备注射和输液用无菌产品时。然而，目前尚无关于在测量小体积液体时正确使用注射器的官方指南。本项目的目的是确定市售注射器在无菌产品制备过程中测量小体积液体时的准确性和精密度，以便为注射器尺寸选择提供建议。为了评估注射器的精密度和准确性，3名独立研究人员使用连接18G、1½英寸针头的1、3、5、10或20mL注射器，从小瓶中抽取注射用无菌水，测量其5%、10%或20%（每种n = 30）的体积。使用电子天平通过重量法测量输送体积，并利用水的比重（1.0）将其转换为体积。准确性以平均值和标准差表示，而精密度以相对标准偏差百分比表示。使用带有Bonferroni校正的单因素方差分析评估差异，显著性设定为< 0.05。与理论输送体积相比，精密度和准确性在研究人员内部和之间都存在高度变异性，且通常差异显著（< 0.05）。当测量的体积小于注射器标称容量的20%时，观察到出现不可接受误差（>5%）的可能性增加。尽管制造商规定的准确度为±5%，但平均误差百分比范围为1.4%至18.6%，这表明正确的操作技术是小体积测量中的主要因素。除了对注射器使用者进行适当的、经过验证的培训外，我们建议使用者在选择尽可能接近所需测量值的注射器时，测量的体积不低于注射器指示体积的20%。如有可能，应将非常小的体积进行稀释，以达到可用最小注射器的最小体积。实施这些建议将提高给药的准确性，并最终提高患者安全性。
