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.