Fig. 2

Fishbone diagram of possible influencing factors for repeated puncture or catheterization failure. ① Human. Doctor: unskilled operation, not strictly following the operation process. Patient: obesity, short neck, malnutrition, body position limitation (not being able to lie flat for any reason), vascular variation, vascular collapse, poor cooperation. ② Material:poor quality of puncture instruments, guide wire defect. ③ Environment: insufficient light, emergency catheterization. ④ Method: failure to strictly implement the operator admittance system, imperfect management system, insufficient operation process monitoring, inflexible training method