From the Department of Anaesthesiology and Reanimation, University of Health Sciences, Antalya Training and Research Hospital, Antalya (ASK, FE, FO) and Department of Anaesthesiology and Reanimation, Karabuk University Training and Research Hospital, Karabuk, Turkey (UA).
Eur J Anaesthesiol. 2019 Dec;36(12):911-917. doi: 10.1097/EJA.0000000000001091.
Skin temperature measurements after peripheral nerve block can be used as an easy and objective method to help predict block success. Thermochromic nail polishes are popular cosmetic products especially among young women. The colour change of nail polish is based on a thermochromic reaction as the temperature changes.
The aim of this study was to test the hypothesis that the success of infraclavicular brachial plexus blocks (IBPBs) can be predicted by the colour change in thermochromic nail polish, which depends on skin temperature changes.
A prospective cohort study.
Training and research hospital from December 2018 to March 2019.
A total of 50 patients who received IBPB for forearm, wrist or hand surgery were included.
Thermochromic nail polish was applied to the nails of both hands of all patients before the block. Reaction of the nail polish in both hands was photographed immediately after application of nail polish and at 30 min after performing the block. The digital photographs of each patient were evaluated by observers. To evaluate the validity of the colour change in nail polish in predicting a successful IBPB, sensitivity, specificity, positive and negative predictive values and positive and negative likelihood ratios were estimated.
The positive predictive value for colour change in thermochromic nail polish predicting a successful IBPB was 96% [95% confidence interval (CI) 90 to 98] and sensitivity was 94% (95% CI 87 to 97). Fleiss kappa value showed substantial agreement (0.76; 95% CI 0.59 to 0.93) in the assessment of interobserver agreement.
The current study demonstrates that the colour change in thermochromic nail polish is a valid and reliable indicator for the prediction of block success.
ClinicalTrials.gov identifier: NCT03767868.
外周神经阻滞（Plexus Block）后测量皮肤温度可作为一种帮助预测阻滞成功的简便、客观的方法。变色指甲油是一种流行的化妆品，尤其受到年轻女性的喜爱。指甲油的颜色变化是基于温度变化的热致变色反应。
本研究旨在检验如下假设，即通过依赖于皮肤温度变化的热致变色指甲油颜色变化，可以预测锁骨下臂丛阻滞（IBPB）的成功。
前瞻性队列研究。
2018 年 12 月至 2019 年 3 月期间的培训和研究医院。
共纳入 50 例因前臂、手腕或手部手术而接受 IBPB 的患者。
所有患者在阻滞前将变色指甲油涂在双手指甲上。涂指甲油后立即、阻滞后 30min 对双手指甲油的反应进行拍照。由观察者对每位患者的数字照片进行评估。为评估指甲油颜色变化预测 IBPB 成功的有效性，评估了敏感性、特异性、阳性和阴性预测值以及阳性和阴性似然比。
变色指甲油预测 IBPB 成功的阳性预测值为 96%（95%置信区间 90%98%），敏感性为 94%（95%置信区间 87%97%）。观察者间评估的 Fleiss kappa 值显示具有高度一致性（0.76；95%置信区间 0.59~0.93）。
本研究表明，变色指甲油的颜色变化是预测阻滞成功的有效且可靠的指标。
NCT03767868。
