探讨PDSA循环在提高胎儿大脑中动脉（MCA）超声检查质量中的应用价值。

参照PDSA循化过程，计划（P）：选取2019年7月至12月重庆市妇幼保健院超声科影像归档和通信系统中MCA血流频谱测量300例，按质量控制标准进行评分；以甲类图像数量＞95%为质量改进目标，针对存在的问题制定改进措施；执行（D）：2020年1月至6月实施各项改进措施；研究（S）：抽查实施改进措施后500例MCA血流频谱测量图像进行图像评分，分析PDSA循环法实施前、后的图像评分情况；实施（A）：通过持续推进和随访反馈等措施确定阶段改进成果。采用χ2检验对PDSA循环法实施前、后的图像评分进行统计分析。

PDSA循环法实施前MCA血流频谱甲类图像占比81.0%（243/300），实施后甲类图像占比96.8%（484/500），图像质量明显提高，差异有统计学意义（χ2=24.793，P＜0.01）。改进前图像扣分项目主要是未调整声束与血流方向间夹角（19.35%），参数调节不当导致舒张期血流未显示（18.75%），测量时取样框未靠近Willis环（14.29%）；改进后图像扣分项目主要是未调整声束与血流方向间夹角（22.83%），Willis动脉环显示不清晰或不完整（16.30%），取样框过大或过小（15.22%）；表明实施阶段对舒张期低速血流测量参数调节方面的培训有成效，但在频谱波形正常显示的情况下，检查者不注重对血流图像、测量角度及取样容积的关注。

PDSA循环的运用有效提高了MCA血流频谱图像质量，在建立超声单病种质量控制体系的过程中可以将其作为质量控制工具应用。

To explore the application of PDSA cycle in the quality control of ultrasonic detection of fetal middle cerebral artery (MCA) blood flow spectrum.

(Plan) Three hundred images of fetal MCA blood flow spectrum obtained in Chongqing Health Center for Women and Children from July 2019 to December 2019 were evaluated according to the quality control standard. The percentage of grade A images ＞95% was the goal of quality improvement. The formulation of improvement measures was based on the existing problems. (Do) The improvement measures were implemented from January to June 2020. (Study) Five hundred MCA blood flow spectrum images of the same period were evaluated. The image scores before and after quality control were analyzed. The proportions of grade A standard images before and after PDSA cycle were analyzed by chi-square test. (Action) Continuous improvement and follow-up feedback were used to determine the stage improvement results.

MCA bloodstream spectrum grade A images accounted for 81.0% (243/300) before and 96.8% (484/500) after the implementation of PDSA cycle. The image quality was significantly improved after the implementation of PDSA cycle (χ2=24.793, P＜0.01). Before improvement, the image deficiency items mainly included the angle between the acoustic beam and blood flow (19.35%), the absence of diastolic blood flow (18.75%), and the position of the sampling frame (14.29%). The main defects of the improved images were the angle between the acoustic beam and blood flow (22.83%), images of the Willis arterial ring (16.30%), and the size of the sampling volume (15.22%). The results showed that the training on the adjustment of the parameters of diastolic low speed blood flow measurement was effective, but the examinees did not pay attention to the blood flow image, measurement angle and sampling volume when the spectrum waveform was normal.

The application of PDSA cycle effectively improves the image quality of MCA blood flow spectrum, which is worthy of being used as a quality control tool in the process of establishing the quality control system of ultrasonic detection of single diseases.