Table 2
R–R interval changes following a 60° head-up tilt
| No of subjects | Mean (SD) heart rate (bpm) | Mean (SD) minimim R-R (ms) | Mean (SD) maximim R-R (ms) | Mean (SD) ratio(max:min R–R) | Mean (SD) No of beats (min-max) | |
|---|---|---|---|---|---|---|
| Quiet sleep | ||||||
| Prone | 33 | 128.8 (6.9) | 410.8 (35.9) | 550.1 (82.0) | 1.3 (0.3) | 15.3 (6.2) |
| Supine | 34 | 125.5 (8.8) | 414.1 (28.6) | 585.0 (82.4) | 1.4 (0.2) | 15.3 (5.7) |
| Active sleep | ||||||
| Prone | 23 | 129.3 (7.8) | 390.3 (27.6) | 517.5 (56.4) | 1.3 (0.1) | 15.0 (5.0) |
| Supine | 20 | 131.5 (7.9) | 387.0 (29.9) | 522.5 (66.0) | 1.3 (0.1) | 15.1 (6.2) |
