Table 1 The patient test
From: A new device for 100 per cent humidification of inspired air
Humid-Heat | Fisher & Paykel MR730 | P | |
Duration of the test (h) | 24 ± 0.5 | 22± 4.0 | 0.27 |
Change in the patient's body temperature (°C) | -0.28 ± 0.36 | +0.01 ± 1.1 | 0.56 |
Change in the temperature at the Y-piece or the flex-tube (°C) | -0.13 ± 0.64 | 0.0 ± 0.54 | 0.71 |
Suctions (n) | 10.4 ± 3.9 | 9.2 ± 3.2 | 0.75 |
Saline instillations (n) | 5.9 ± 3.1 | 4.6 ± 2.9 | 0.43 |
Total volume of saline instilled (ml) | 30 ± 20 | 24 ± 23 | 0.41 |
No of nebulizations (salbutamol 2.5 mg plus 200 mg N-acetylcystein | 3.6 ± 1.8 | 3.9 ± 2.0 | 0.75 |
diluted with saline to a total of 5 ml) | |||
Quality of secretions at the start of the experiment (thick, normal, thin) (n) | thick 2, normal 2, thin 4 | thick 4, normal 3, thin 1 | 0.26 |
Quality of secretions at the end of the experiment, patients (n) | thick 0, normal 5, thin 3 | thick 1, normal 5, thin 2 | 0.18 |
Change in thickness of secretions (i = increase, d = decrease, | d = 3, i = 3, O = 2 | D = 3, i = 1, O = 4 | 0.44 |
O = no change), patients (n) | |||
Change in airway pressure at a prolonged expiratory pause | 0 | 0 | 0.99 |
Water consumed/h (ml) | 5.6 ± 1.2 | 30 ± 15 | 0.0008 |
Water consumed/l inspired gas (ml) | 0.009 ± 0.003 | 0.043 ± 0.018 | 0.0008 |
Number of times that the water traps were emptied | 0 | 8.3 ± 3.2 | 0.0008 |
Total amount of fluid in the water traps (ml) | 0 | 213 ± 84 | 0.0008 |
Number of changes of machine filters due to excessive water condensation | 0 | 4.7 ± 1.6 | 0.0008 |