A-217 Selection of difficult factors in blood collection for outpatients through analysis of operational data

Abstract Background In clinical examinations, it is important to maintain quality and safety with limited resources. Blood collection, which is invasive and data-intensive, requires efforts to reduce the incidence of patient re-puncturing (“failure rate”) and shorten blood collection time by analyzing operational data. Akinaga et al. (2017) developed the blood collection matching system that assigns a patient*s blood collection difficulty level and a blood collector*s skill level, and showed that the system was effective in reducing the failure rate and blood collection time. However, as a decade has passed since the system’s implementation, changes in patient backgrounds and accumulated practical knowledge necessitate a review of the factors influencing blood collection difficulty. This study aims to identify factors with minimal impact on determining blood collection difficulty based on the implemented blood collection difficulty decision flow. Methods First, we extracted factors with minimal impact on the failure rate among the factors that determine the current difficulty level of blood collection (blood vessel condition, blood collection site, procedure, etc.). We used logistic regression analysis based on approximately 100,000 operational data points collected at Iizuka Hospital in FY2023 and interviewed blood collection room managers. Next, we confirmed the impact of the extracted factors on the failure rate by testing for differences in population proportions of the failure rate, stratified by the extracted factors and through interviews with managers and clinicians. Finally, we retrospectively verified numerically whether the failure rates were equivalent or lower after removing the extracted factors using the operational data. Results Extraction of factors with a minimal impact on the failure rate: After logistic regression analysis and expert reviews, we identified the following patient characteristics: taking warfarin, using hot packs, and not using a rubber tourniquet. Confirmation of the impact of the extracted factors: As a result of the population proportion test, we found no statistically significant correlation between the extracted factors and a higher failure rate. Furthermore, interviews revealed that the extracted factors, once considered indicators of difficulty, have shifted in interpretation to operational reminders due to changes in work practices since the system*s implementation. We also found that there was no direct effect on the difficulty of puncturing blood vessels from a clinical viewpoint. These statistical and clinical viewpoints suggested that the extracted factors were not factors that increase patients* blood collection difficulty. Verification of the failure rate after removing extracted factors: After numerical validation with the extracted factors removed, we found that failure count decreased from 1,898 to an expected 1,770 and the failure rate from 1.78% to an expected 1.66%, confirming the limited effect of the extracted factors. Conclusion In this study, we were able to remove the factors that had minimal impact on blood collection difficulty from the implemented blood collection difficulty decision flow, and clarify the factors influencing patient re-puncturing. However, a remaining challenge is the reconstruction of the blood collection difficulty decision flow, incorporating factors that have yet to be evaluated.