Table 1.
Hemodynamic responses to passive stretch and active contraction
| Spontaneous breathing | Controlled breathing | |||||
|---|---|---|---|---|---|---|
| Baseline | Stretch | Contraction | Baseline | Stretch | Contraction | |
| Heart rate (bpm) | 64.1 ± 3.4 | 62.6 ± 3.6 | 64.4 ± 3.1 | 64.6 ± 3.4 | 64.4 ± 3.5 | 66.4 ± 3.0 |
| MSNA (bursts min−1) | 13.2 ± 1.8 | 14.1 ± 1.8 | 13.7 ± 2.0 | 12.4 ± 1.9 | 13.7 ± 1.7 | 14.6 ± 2.2 |
| MSNA (bi) | 22.2 ± 3.7 | 24.0 ± 3.6 | 21.8 ± 3.1 | 20.7 ± 3.7 | 22.4 ± 3.4 | 22.7 ± 3.2 |
| MSNA (units min−1) | 227 ± 36 | 250 ± 33 | 252 ± 44 | 205 ± 32 | 240 ± 37 | 297 ± 47 |
| SBP (mmHg) | 121.3 ± 4.6 | 123.1 ± 4.4 | 127.3 ± 4.4 | 123.2 ± 4.8 | 123.0 ± 4.7 | 126.2 ± 3.9 |
| DBP (mmHg) | 68.6 ± 2.0 | 69.3 ± 2.7 | 72.1 ± 2.1 | 68.7 ± 1.9 | 69.5 ± 2.0 | 71.0 ± 2.4 |
| MAP (mmHg) | 86.2 ± 2.6 | 87.2 ± 2.9 | 90.5 ± 2.6 | 86.9 ± 2.5 | 87.3 ± 2.6 | 89.4 ± 2.6 |
| Resp. (cycles min−1) | 15.7 ± 0.7 | 15.2 ± 0.6 | 14.4 ± 0.7 | 15.0 ± 0.1 | 14.9 ± 0.1 | 14.7 ± 0.1 |
| Force (kg) | — | 6.8 ± 0.6 | 16.8 ± 1.5* | — | 6.7 ± 0.6 | 17.7 ± 1.5* |
| Subject number | 12 | 12 | 11 | 12 | 12 | 10 |
Values are means ±s.e.m. Mean blood pressure (MAP) was calculated as one-third systolic blood pressure (SBP) pulse, two-thirds diastolic blood pressure (DBP), which was measured by auscultation of brachial artery. MSNA, muscle sympathetic nerve activity, bi: bursts per 100 heart beats. The forces were the mean values of the forces only during the stretch or contraction.
*
Significantly different from stretch (P < 0.05).