Effect of CPAP 0, 5, and 10 cm H2O on muscle sympathetic nerve activity, blood pressure, and ventilation
| Patients (n=10) | Controls (n=10) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| CPAP 0 | CPAP 5 | CPAP 10 | p Value (ANOVA) | CPAP 0 | CPAP 5 | CPAP 10 | p Value (ANOVA) | |||
| MSNA (bursts/min) | 43 (14) | 45 (13) | 47 (13)2-150 | 0.03 | 30 (5) | 32 (6) | 35 (6)2-150 2-151 | < 0.001 | ||
| MSNA/TA (au) | 349 (48) | 411 (53)2-150 | 425 (44) | 0.04 | 338 (79) | 372 (90) | 419 (104)2-150 | 0.02 | ||
| Heart rate (beats/min) | 64 (7) | 64 (7) | 64 (7) | NS | 62 (2) | 63 (2) | 64 (2) | NS | ||
| Systolic BP (mm Hg) | 110 (17) | 114 (22) | 115 (20)2-150 | 0.04 | 130 (6) | 129 (6) | 133 (6) | NS | ||
| Diastolic BP (mm Hg) | 65 (8) | 70 (11)2-150 | 72 (10)2-150 | < 0.001 | 79 (3) | 79 (3) | 83 (3)2-150 2-151 | < 0.001 | ||
| Respiratory rate (breaths/min) | 15 (5) | 13 (4) | 13 (2) | NS | 12 (1) | 12 (1) | 12 (1) | NS | ||
| Tidal volume (ml) | 545 (179) | 536 (173) | 535 (154) | NS | 536 (61) | 525 (79) | 648 (118) | NS | ||
| Pco 2 (kPa) | 4.93 (0.53) | 4.53 (0.67)2-150 | 4.27 (0.80)2-150 2-151 | < 0.001 | 5.20 (0.13) | 4.93 (0.13)2-150 | 4.53 (0.27)2-150 | 0.007 | ||
| Oxygen saturation (%) | 95.7 (0.6) | 96.4 (0.4)2-150 | 96.6 (0.7)2-150 | 0.004 | 97.3 (0.3) | 97.4 (0.3) | 97.5 (0.3) | NS | ||