Table 2.

Distribution of species of bacteria and fungi according to its frequencies in cultures of tracheal aspirates, sonication fluid, and centrifuged sonication fluid.

Microorganisms	(N = 151)	TA (N = 53)	SF (N = 48)	CSF (N = 50)	p-Valuea
Pseudomonas spp.	23.8% (36/151)	24.52% (13/53)	22.91% (11/48)	24% (12/50)	0.98
Streptococcus spp.	18.5% (28/151)	20.75% (11/53)	18.75% (9/48)	16% (8/50)	0.90
Acinetobacter spp.	15.9% (24/151)	13.2% (7/53)	16.66% (8/48)	18% (9/50)	0.80
CNSb	11.2% (17/151)	9.43% (5/53)	10.41% (5/48)	14% (7/50)	0.75
Klebsiela spp.	8.6% (13/151)	9.43% (5/53)	8.33% (4/48)	8% (4/50)	0.98
Candida spp.	7.3% (11/151)	7.54% (4/53)	6.25% (3/48)	8% (4/50)	0.94
S. aureusc	4.6% (7/151)	5.66% (3/53)	4.16% (2/48)	4% (2/50)	0.92
Chromobacterium spp.	2% (3/151)	1.88% (1/53)	2.08% (1/48)	2% (1/50)	0.99
Enterococccus spp.	2% (3/151)	0	4.16% (2/48)	2% (1/50)	0.33
Enterobacter spp.	2% (3/151)	1.88% (1/53)	2.08% (1/48)	2% (1/50)	0.99
Neisseria spp.	2% (3/151)	1.88% (1/53)	2.08% (1/48)	2% (1/50)	0.99
C. indologenesd	0.66% (1/151)	0	2.08% (1/48)	0	0.34
Escherichia coli	0.66% (1/151)	1.88% (1/53)	0	0	0.41
Rhodotorola rubra	0.66% (1/151)	1.88% (1/53)	0	0	0.41

TA, tracheal aspirate; SC, non-centrifuged sonication fluid; CSF, centrifuged sonication fluid.

^aMicrobiologic results were summarized as frequencies and percentages and also compared using the chi-square or Fisher's exact test as appropriate to categorical variables. All tests were two sided and p-values less than 0.05 were considered statistically significant.

^bCoagulase-negative staphylococci.

^cStaphylococcus aureus.

^dChryseobacterium indologenes.