Characteristics of 31 patients on negative pressure ventilation (shell or tank)
| Diagnosis | Poliomyelitis | Non-Duchenne's myopathies |
Motor neurone disease | Diaphragmatic paralysis | Multiple sclerosis |
| No. of patients (M/F) | 25 (13/12) | 2 (1/1) | 2 (1/1) | 1(0/1) | 1(0/1) |
| Age when ventilator started (years) | 26.0 (10.2) | 18.5 (0.71) | 62.0 (12.7) | 29 | 47 |
| Height (cm) | 169.1 (11.5) | 156.2 (34.1) | 161.3 (1.8) | 160 | 154.9 |
| Weight (kg) | 57.7 (12.2) | 33.2 (1.3) | 44.8 (8.7) | 56.4 | 57.7 |
| FVC (ml; % predicted) | |||||
| a | 800 (383); 20 (8)% | 625 (460); 19 (9)% | 950 (50); 34 (3)% | 1300; 44% | 1300; 63% |
| b | 730 (336); 19 (7)% | 550 (495); 14 (14)% | 300 (20); 9 (3)% | 1200; 38% | 1270; 57% |
| Pco 2(mm Hg) | |||||
| a | 46.1 (10.0)2-151 | 51.5 (0.71) | 50.5 (6.5) | 62 | 43 |
| b | 46.5 (14.5) | 68.5 (14.8) | 46.5 (9.2) | 48 | 34 |
| Time on non-invasive ventilation (months) | 290 (148)2-164 | 46 (31) | 174 (229) | 46 | 396 |
| Gain or decline in FVC | |||||
| ml/year | −4.8 (13.8)2-152 | −81.3 (97.2) | −25.0 (0) | −26.1 | −7.0 |
| % predicted/year | −0.09 (0.31) | −2.0 (1.4) | −0.8 (0) | −1.6 | −1.4 |
| No. of patients eventually needing trachostomy | 142-153 | 2 | 1 | 0 | 0 |
| No. of deaths | 62-150 | 0 | 2 | 0 | 1 |
Values are mean (SD) unless otherwise stated.
a = before ventilation; b = near end of period on ventilation; FVC = forced vital capacity; Pco 2 = carbon dioxide tension.
↵2-151 Significantly different from polio-M/NIPPV patients (table 3), p<0.05 (Wilcoxon rank sum test).
↵2-164 Significantly different from polio-M/NIPPV patients (table 3), p< 0.01 (Wilcoxon rank sum test).
↵2-152 Significantly different from polio-M/NIPPV patients (table 3), p<0.01 (Wilcoxon rank sum test).
↵2-153 Significantly different from polio-M/NIPPV patients (table 3), p<0.01 (Wilcoxon rank sum test).
↵2-150 Significantly different from polio-M/NIPPV patients (table 3), p<0.01 (Wilcoxon rank sum test).