The Study Of An Independent Research Model Used By Novices For Learning Ultrasound-guided Nerve Block

Objective:Ultrasound guided regional nerve block is becoming more and more popular,but for beginners,it is still very difficult to master this technology.The training period of clinical teaching is long,which causes the risks of psychological and physical trauma to patients,and students nervous will also affect the mastery of the technology.Therefore,the method of simulation teaching is preferred to achieve the teaching purpose of ultrasound-guided regional nerve block technology.However,it is still lack of a universally accepted standardized teaching program and a recommended simulator.This study aimed to seek a model of ultrasound-guided continuous nerve block training that is simple and close to clinical practice with high repeatability,and further explore the use of this model in regional block training and its impact on beginners’ mastery of ultrasound-guided regional block technology.Method:Part 1:Improve the existing organic model,add inorganic materials to simulate the structure of nerves,blood vessels and other structures,and use appropriate materials to make the ultrasound-guided continuous nerve block model.Part 2:Training the beginners with our self-developed model.Ultrasound-guided nerve block catheterization technology is the most difficulty technology in regional anesthesia,the learning curve was obtained through the operation time.Analyze the number of practices needed to achieve technical stability,satisfaction scores,and the most common mistakes in the exercise.Part 3:Two years of follow-up were conducted for two groups of trainees who had participated in self-developed model training(model group)and those who had not participated in self-developed model training(routine group),a questionnaire survey was conducted for both two groups,and theoretical and practical assessment was conducted to observe the effect of using self-developed models to simulate teaching.Results:Part 1:The ultrasound images of inorganic materials such as rubber tubing,barium line and coupling agent were similar to nerves and blood vessels.When using the out-of-plane technique,the ultrasound image of the needle tip is clear,and the breakthrough sense of puncture needle through the organic pork fascia is very obvious.After rapid injection of 5ml normal saline,the liquid dark area("doughnut mark")appeared.When the nerve block catheter is placed through the puncture needle in the fascia gap where the "nerve" is located,it can also be clearly displayed in the ultrasound image.A national invention patent was obtained for the preparation of this ultrasonic guided nerve block model with organic and inorganic materials.Part 2:We trained the beginners with our self-developed model,and obtained the following exponential attenuation function through the operation time:y=(120-78.77)× exp(-0.1032 × x)+ 78.77,T1/2 = 6.7 attempts,according to this formula,27 exercises are needed to achieve technical stability.The satisfaction score of the first trial was 2.5±1.9 and significantly improved after the third trial(p = 0.015).The most common mistakes during practice from high to low frequency were as following:(QCB7)wrong catheterization(n=280),(QCB5)Probe position cannot be identified(n=174),(QCB1)blind tip(n=128),(QCB4)wrong target position judgment(n=118),(QCB2)Needle depth error(n=92),(QCB3)target damage(n=26),(QCB8)watch the hands(n=10),no student(QCB6)holds the probe technique error(n=0).Part 3:There were no significant difference in the two theoretical examinations and the self-evaluation of satisfaction with the two groups of trainees who had participated in the self-developed model training(model group)and those who had not participated in the self-developed model training(routine group).However,the students who had used this model had higher confidence,and the success rate of examining the needle tip on the model was higher when they graduated.Conclusion:Our self-developed ultrasound-guided nerve block model is a simple and practical training tool,which can be used to teach and train the ultrasound-guided nerve block technology.After 27 attempts,the operation technology of this model can be mastered.Feedback can be given to participants by measuring their low-quality behavioral evaluation and satisfaction scores while operating on the model.Add our self-developed model into the teaching practice of conventional regional block helps to arouse students’interest,improve their confidence and improve the ultrasonic needle display technology.This model is worthy to be applied to clinical skills training and to evaluate ultrasound-guided nerve block technology.