1. 2022;25;501-507Aspirin Cessation Before Interventional Procedures: Not Blindly Following Guidelines but Making Test-based Decisions
   Cross-Sectional Study
   Kyeong Hwan Seo, MD, Francis Sahngun Nahm, MD, PhD, Woong Ki Han, MD, Ho Young Gil, MD, Jung Eun Kim, MD, PhD, Eun Joo Choi, MD, and Pyung Bok Lee, MD.

BACKGROUND: Deciding whether to continue or discontinue aspirin prior to interventional procedures is a major concern for pain physicians. Many guidelines have been published on the discontinuation of aspirin before invasive procedures; however, the recommendations are inconsistent and do not consider individual platelet function. Furthermore, many studies have shown a high prevalence of aspirin resistance  in patients taking this medication.

OBJECTIVES: To determine the necessity of discontinuing aspirin prior to interventional pain procedures in relation to individual platelet function.

STUDY DESIGN: Multicenter, cross-sectional study.

SETTING: University-affiliated hospitals.

METHODS: We examined platelet function among patients scheduled for an interventional pain procedure by measuring their closure time using collagen/epinephrine cartridges in a commercial platelet-function analyzer. The patients were categorized into either an aspirin-taking or nonaspirin-taking group (Group A or Group N, respectively). The proportion of patients who showed normal/abnormal platelet function was calculated and compared between the groups.

RESULTS: A total of 1,111 patients were included in this study. In Group A, 56.4% (102/181) showed normal platelet function, whereas 43.6% (79/181) showed abnormal platelet function. In Group N, 85.8% (798/930) and 14.2% (132/930) showed normal and abnormal platelet function, respectively.

LIMITATION: The proportion of laboratory, not clinical aspirin resistance was evaluated. Factors affecting platelet function were not investigated exhaustively.

CONCLUSION: The high prevalence of normal platelet function in patients taking aspirin suggests no necessity of discontinuation before procedures in such patients. Abnormal platelet function can occur even in patients who are not taking aspirin. Therefore, platelet function should be measured and considered on a case-by-case basis prior to interventional procedures, and discontinuation of aspirin should be decided based on these factors.

KEY WORDS: Aspirin, collagen, epinephrine, guideline, nerve block, pain, platelet aggregation,; platelet-function tests