| Items | Breakdown | Cases (n = 258) | % |
| Drain and tube | Self-removal | 113 | 43.8 |
| Damage and cutting | 29 | 11.2 | |
| Coming off a connection socket | 23 | 8.9 | |
| Natural removal | 17 | 6.6 | |
| Occlusion | 12 | 4.7 | |
| Mistake of a connection socket | 5 | 1.9 | |
| Extravasation of drip infusion | 2 | 0.8 | |
| Error of root clamp | 0 | 0.0 | |
| Mistake of manipulation of T-shape stopcock | 0 | 0.0 | |
| Others | 57 | 22.1 |