H. Dupont et al., Impact of appropriateness of initial antibiotic therapy on the outcome of ventilator-associated pneumonia, INTEN CAR M, 27(2), 2001, pp. 355-362
Objectives: To evaluate the impact of appropriate initial antibiotic therap
y (AB) on the outcome of ventilator-associated pneumonia (VAP).
Design: Retrospective study (1992-97).
Patients and methods: Episodes of VAP diagnosed on both clinical and microb
iological criteria after greater than or equal to 48 h of mechanical ventil
ation (MV). Initial AB was considered appropriate when all significant orga
nisms were susceptible to at least one of the antibiotics started after dis
tal bronchial sampling. Antibiotic treatment was modified within 48 h when
susceptibility testing was available. Outcome was recorded at the ICU and h
ospital discharge.
Results: One hundred and eleven patients were included (SAPS II = 48 +/- 18
, age = 62 +/- 14 years, mean duration of MV before VAP = 12 +/- 9 days). I
nitial AB was appropriate in 55 patients (49.5 %). No difference between ap
propriate initial AB and inappropriate initial AB was found concerning seve
rity indices at the time of VAP diagnosis. ICU length of stay was shorter w
ith appropriate initial AB than with inappropriate initial AB for survivors
(12 +/- 11 days vs 20 +/- 24 days, P = 0.01). Crude hospital mortality ten
ded to be lower with appropriate initial AB than with inappropriate initial
AB (47.3 % vs 60.7 %, odds ratio = 1.72, 95 % CI = 0.81-3.7). Relative cru
de mortality reduction with appropriate initial AB was 22 %, 95 % CI = -10
% to 45 %.
Conclusion: Inappropriate initial AB of VAP during the first 48 h increased
ICU length of stay after VAP diagnosis and tended to increase crude hospit
al mortality despite equal severity of illness at the time of VAP diagnosis
, when compared to appropriate initial AB in a population of 111 ICU patien
ts.