Evaluation of the position of the needle tip during thoracentesis: Experimental study.

Abstract

Introduction:Thoracentesis is performed to both diagnose and/or treat pleural effusion, and several important complications of thoracentesis are occasionally observed. To assess precise thoracentesis procedures, we evaluated the position of the needle tip during thoracentesis by using a thoracentesis unit, comparing experienced and inexperienced groups.Methods:Twenty eight physicians (19 board-certified pulmonologists as an experienced group and the remaining 9 as an inexperienced group) participated at Fukujuji Hospital in January 2021. All participants performed 2 punctures with a handmade thoracentesis unit and measured the needle‘s angle to the midline.Results:The median distance from the needle tip to the midline when the needle was inserted 5 cm (D5) was 0.47 cm (range 0.06–1.05), and the median difference between D5 on the 1st puncture (D51st) and D5 on the 2nd puncture (D52nd) was 0.22 cm (range 0.00–0.69). D5 was shorter in the experienced group than in the inexperienced group (median 0.40 cm (range 0.06–0.66) vs 0.58 cm (range 0.44–1.05), P < .001). There were no significant differences in the D51st and D52nd distances between the experienced and inexperienced groups (median 0.22 cm (range 0.00–0.40) vs 0.41 cm (range 0.04–0.69), P = .094). When 4 areas were divided by the x-axis and y-axis, 32 punctures (55.2%) deviated to the right-upper quadrant, and 25 (86.2%) of participants made the 1st puncture and 2nd puncture in the same direction.Conclusions:All doctors should know that the needle direction might shift by approximately 1 cm, and more than half of the practitioners punctured towards the upper right.