Dynamic hyperinflation and intrinsic positive end-expiratory pressure in ARDS patients

Table 4 Gas exchange at different levels of PEEP in patients with and without intrinsic PEEP

Parameter	Patients with intrinsic PEEP (n = 87)	Patients without intrinsic PEEP (n = 130)	P_PEEPi	P_PEEP	P_{PEEPix PEEP}
PaO₂ (mmHg)			0.761	*< 0.001*	0.939
5 cmH₂O	71 [64–83]	73 [63–93]
15 cmH₂O	94 [75–124]	99 [80–123]
PaO₂/FiO₂			0.118	*< 0.001*	0.957
5 cmH₂O	138 [100–183]	151 [119–185]
15 cmH₂O	194 [144–252]	200 [159–259]
PaCO₂ (mmHg)			0.111	0.518	0.787
5 cmH₂O	44 [40–52]	44 [38–51]
15 cmH₂O	44 [41–52]	38 [22–42]
Alveolar dead space (%)			0.279	0.345	0.425
5 cmH₂O	20 [12–26]	23 [13–30]
15 cmH₂O	19 [13–27]	21 [11–29]
Alveolar dead space (mL)			0.186	*0.010*	0.107
5 cmH₂O	105 [66–137]	111 [74–153]
15 cmH₂O	98 [68–131]	105 [62–140]

Data are expressed as median [I.Q. range] as appropriate
Two-way repeated measures analysis of variance (ANOVA) followed by all pairwise multiple comparison procedures (Holm-Sidak method) was used for analysis
p < 0.05 raising end-expiratory pressure from 5 to 15 cmH₂O
There are no significant interactions
n sample size, PEEP positive end-expiratory pressure
Italics: for all the statistical data
Bold italics: for statistical significant data

ISSN: 1364-8535