CLINICAL STUDY Periprocedural Major Bleeding Risk of Image-Guided Percutaneous Chest Tube Placement in Patients with an Elevated International Normalized Ratio Patrick. J. Navin, MBBChBAO, Mariah L. White, MD, Francis C. Nichols, MD, Darlene R. Nelson, MD, John J. Mullon, MD, Jennifer S. McDonald, PhD, Thomas D. Atwell, MD, and Michael R. Moynagh, MBBChBAO, MRCSI, FFRCSI ABSTRACT Purpose: To evaluate the incidence of major hemorrhage after image-guided percutaneous chest tube placement in patients with an abnormal international normalized ratio (INR) measured before the procedure. Materials and Methods: Between January 2013 and September 2017, 49 image-guided percutaneous chest tubes were placed in 45 adult patients who had an elevated INR of greater than 1.6. Data collected included routine serum pre-procedure coagulation studies, indication for chest tube placement, insertion technique, size of chest tube, and presence of complications after drain placement. Major bleeding complications were defined using the Society of Interventional Radiology classification system. Results: Mean patient age was 62 years (range, 22–94 years), with median American Society of Anesthesiologists score of 4. Mean INR was 2.1 (range, 1.7–3), with 21 (43%) procedures with an INR between 1.7 and 1.9, 20 (41%) procedures with an INR between 2.0 and 2.4, and 8 (16%) procedures with an INR between 2.5 and 3.0. Computed tomography guidance was used for 27 (55%) procedures; ultrasound guidance was used for 22 (45%) procedures. Median size of chest tube was 10 Fr (range, 8–14 Fr) used in 27 (55%) procedures. No major bleeding complications were observed. There was a small, significant decrease in mean hemoglobin after the procedure (mean ¼ 0.9g/dL; P < .0001), which correlated to increasing chest tube size (P ¼ .0269). Conclusions: No major bleeding complications were observed after image-guided percutaneous chest tube placement in patients with an elevated INR. Major bleeding complications in these patients may be safer than initially considered, and this study encourages the conduct of larger trials for further evaluation. ABBREVIATION INR ¼ international normalized ratio Percutaneous image-guided small bore chest tube (chest pleural catheter) placement is a commonly performed pro- cedure for the treatment of pneumothorax and pleural effusions, with over 1 million placed annually (1). Minor bleeding rates have been reported between 1% and 2% for ultrasound-guided chest tube placement with normal coag- ulation profiles (2,3). Prior management guidelines have considered chest tube placement to be a procedure of moderate risk for bleeding, with a recommendation to cor- rect underlying coagulopathy prior to intervention (4,5). Although helpful, these guidelines have lacked sufficient evidence to support such management and may even place patients at risk when reversing clinically indicated anticoagulation (6,7). Evidence is available to support the safety of thoracentesis in patients with abnormal serum screening studies (5,8,9). No studies are available evaluating the same bleeding risk related to percutaneous chest tube placement in such potentially high-risk patients. From the Departments of Radiology (P.J.N., M.L.W., J.S.M., T.D.A., M.R.M.), General Thoracic Surgery (F.C.N.), and Pulmonary and Critical Care Medicine (D.R.N., J.J.M.), Mayo Clinic, 200 First Street SW, Rochester, MN, 55905. Received June 22, 2018; final revision received July 1, 2019; accepted July 2, 2019. Address correspondence to M.R.M.; E-mail: moynagh.michael@ mayo.edu None of the authors have identified a conflict of interest. © SIR, 2019 J Vasc Interv Radiol 2019; 30:1765–1768 https://doi.org/10.1016/j.jvir.2019.07.002