Double-Wall Puncture Rates for Individual Needles and Some Groupings Based on Tip Sharpness, Gauge, and Length
| Needle Characteristic | Double-Wall Puncture Rate, % | Double-Wall Puncture, n/n | 95% CI, % |
|---|---|---|---|
| Tip Sharpness | |||
| A-bevel, 21 gauge | 8.7 | 13/149 | 4.7-14.5 |
| I-bevel, 20 gauge | 0.0 | 0/11 | 0.0-28.5 |
| B-bevel, all gauges | 11.8 | 8/68 | 5.2-21.9 |
| 21 gauge | 13.5 | 5/37 | 4.5-28.8 |
| 18 gauge | 9.7 | 3/31 | 2.0-25.8 |
| Gauge | |||
| 21 gauge, any bevel, NS± | 9.7 | 18/186 | 5.8-14.9 |
| 20 gauge, I-bevel, NSs-o | 0.0 | 0/11 | 0.0-28.5 |
| 18 gauge, B-bevel, NS± | 9.7 | 3/31 | 2.0-25.8 |
| Length optimization | |||
| NS-, all gauges | 25.0 | 11/44 | 13.2-40.3 |
| 21 gauge, A-bevel and B-bevel | 22.0 | 9/41 | 10.6-37.6 |
| 21 gauge, A-bevel | 18.2 | 6/33 | 7.0-35.5 |
| 21 gauge, B-bevel | 37.5 | 3/8 | 8.5-75.6 |
| 18 gauge B-bevel | 66.7 | 2/3 | 9.4-99.2 |
| NS+, all gauges | 5.4 | 10/184 | 2.6-9.8 |
| 21 gauge, A-bevel | 6.0 | 7/116 | 2.5-12.0 |
| 21 gauge, A-bevel, NSs-o | 9.2 | 7/76 | 3.8-18.1 |
| 21 gauge, A-bevel, NShub | 0.0 | 0/40 | 0.0-8.8 |
| 21 gauge, B-bevel, NSs-o | 6.9 | 2/29 | 0.9-22.8 |
| 20 gauge I-bevel, NSs-o | 0.0 | 0/11 | 0.0-28.5 |
| 18 gauge B-bevel, NSs-o | 3.6 | 1/28 | 0.1-18.3 |
Note: A-bevel, extra-sharp; B-bevel, of lesser sharpness customary for vascular access; I-bevel, of sharpness intermediate between A-bevel and B-bevel.
NS±, with or without a needle stop; NS+, with a needle stop; NS-, without a needle stop; NShub, original manufacturer's hub served as the needle stop; NSs-o, nylon screw-on mechanical needle stop.