Modes of ventilation
| Cases (n=53) | Controls (n=53) | Cases v controls Odds ratio (95% CI) or significance | ||||||
| At age of pneumothorax | ||||||||
| SIPPV | 23 | 17 | ||||||
| SIMV | 3 | 13 | ||||||
| IPPV | 7 | 5 | χ2=20.9, | |||||
| HFO | 13 | 5 | df=6 | |||||
| CPAP | 7 | 4 | p<0.002 | |||||
| None | 0 | 8 | ||||||
| Dead | 0 | 1 | ||||||
| PIP >20 mbar | 15 | 11 | NS | |||||
| Ti >0.3 sec | 13 | 18 | ||||||
| Rate <60 beats/min | 2 | 4 | ||||||
| Previous ventilation | ||||||||
| No change | 36 | 35 | ||||||
| SIPPV→HFO | 9 | 2 | OR=4.5 (1.02 to 19.9) | |||||
| 2 went on to HFO, | ||||||||
| 9 went on to SIMV, | ||||||||
| CPAP or headbox O2 | ||||||||
| SIPPV→SIMV or extubation | 0 | 9 | p=0.00131-150 | |||||
| CPAP | 2 | 0 | ||||||
| HFO | 2 | 0 | ||||||
| IPPV | 2 | 3 | ||||||
| SIMV | 2 | 4 | ||||||
↵1-150 Fisher's exact probability.
SIPPV, Synchronous intermittent positive pressure ventilation; SIMV, synchronous intermittent mandatory ventilation; IPPV, intermittent positive pressure ventilation; HFO, high frequency oscillation; CPAP, continuous positive airway pressure; PIP, peak inspiratory pressure.