Table 2.

Correlations between physiological parameters before and after extubation

	VC Before extubation	FVC Before extubation	MIP Before extubation	MEP Before extubation	PEF Before extubation	PECF Before extubation
VC After extubation
R	0.61
P value	< 0.0001
FVC After extubation
R		0.89
P value		< 0.0001
MIP After extubation
R			0.70
P value			< 0.0001
MEP After extubation
R				0.66
P value				< 0.0001
PEF After extubation
R					0.60
P value					< 0.0001
PCEF After extubation
R						0.58
P value						< 0.0001

For each parameter, the table shows the correlation coefficient and P value

Italics indicate significant data

VC vital capacity, FVC forced vital capacity, MIP maximal inspiratory pressure, MEP maximal expiratory pressure, PEF peak expiratory flow, PCEF peak cough expiratory flow