TABLE 1.
Rohrer's coefficients K2 and K1 of the interpolated pressure‐flow relationships of 3.5, 4.0, and 5.0 mm inner diameter nasopharyngeal tubes (NPTs) using oxygen (O2) and the four sevoflurane (sevo) combinations
| NPT | Gas composition | K1 [cmH2O × s/L] | K2 [cmH2O × s2/L2] | GOF |
|---|---|---|---|---|
| Diameter | Mean (CI) | Mean (CI) | Mean (CI) | |
| 3.5 mm | O2 | 17.6 (17.5‐17.7) | 175.1 (175.0‐175.2) | 0.99 (0.99‐0.99) |
| 2%sevo/O2 | 18.8 (18.7‐18.9) | 200.3 (200.2‐200.4) | 0.99 (0.99‐0.99) | |
| 4%sevo/O2 | 22.1 (22.0‐22.2) | 215.5 (215.4‐215.6) | 0.99 (0.99‐0.99) | |
| 6%sevo/O2 | 24.2 (24.1‐22.3) | 218.7 (218.6‐218.8) | 0.99 (0.99‐0.99) | |
| 8%sevo/O2 | 29.5 (29.4‐29.6) | 219.6 (219.5‐219.7) | 0.99 (0.99‐0.99) | |
| 4.0 mm | O2 | 16.9 (16.8‐17.0) | 86.3 (86.2‐86.4) | 0.99 (0.99‐0.99) |
| 2%sevo/O2 | 13.3 (13.2‐13.4) | 115.8 (115.7‐115.9) | 0.99 (0.99‐0.99) | |
| 4%sevo/O2 | 14.6 (14.5‐14.7) | 126.8 (126.7‐126.9) | 0.99 (0.99‐0.99) | |
| 6%sevo/O2 | 14.4 (14.3‐14.5) | 131.4 (131.3‐119.5) | 0.99 (0.99‐0.99) | |
| 8%sevo/O2 | 18.2 (18.1‐18.3) | 131.9 (131.8‐132.0) | 0.99 (0.99‐0.99) | |
| 5.0 mm | O2 | 7.9 (7.8‐8.0) | 29.0 (28.9‐29.1) | 0.99 (0.99‐0.99) |
| 2%sevo/O2 | 9.0 (8.9‐9.1) | 30.3 (30.2‐30.4) | 0.99 (0.99‐0.99) | |
| 4%sevo/O2 | 9.7 (9.6‐9.8) | 31.6 (31.5‐31.7) | 0.99 (0.99‐0.99) | |
| 6%sevo/O2 | 9.8 (9.7‐9.9) | 33.0 (32.9‐33.1) | 0.99 (0.99‐0.99) | |
| 8%sevo/O2 | 10.3 (10.2‐10.4) | 34.2 (121.1‐121.3) | 0.99 (0.99‐0.99) |
Level of agreement between experimental and interpolated curves was calculated by the goodness‐of‐fit (GOF) test.
Abbreviation: CI, confidential intervals.