P. V. Shiva1, G. Rajendra2, Deepraj Bias3
The aim of the study is to isolate, identify and quantitate bacteria and to perform the antibiotic susceptibility testing from the endotracheal aspirates in RICU patients with suspected Ventilator associated Pneumonia.
MATERIALS AND METHODS
This study is a prospective study conducted on 80 patients during the period of February 2011 to January 2012 in the Department of Anaesthesia & Dept. of Microbiology in Govt. Chest and General Hospital, Hyderabad, in patients, who were suspected to have ventilator associated pneumonia.
Patients above 18 years, who received mechanical ventilation for more than 48 hours and clinically suspected of having contracted VAP were included in this study. Clinical pulmonary infection score (CPIS, was used to diagnose VAP which was evaluated on a daily basis until the patient was on ventilator support. CPIS of >6 was used as diagnostic criteria for VAP till clinically diagnosed ventilator-associated pneumonia was observed.
Patients who were suspected to have clinical and radiological pneumonia when admitted & paediatric patients were excluded.
97 patients taken up for the study were meeting eligibility criteria and were on mechanical ventilation for more than 48 hours, out of which 65 developed VAP. There were 40 males and 25 females. 69 (92%) were multidrug resistant out of the total 75 isolates, and it was observed that not even a single isolate was sensitive to all the drugs tested. Some of this resistance can be because of the presence of various degradative enzymes like ESBLs, AmpC β-lactamase and MBLs within these pathogens. Out of the total 28 isolates of Acinetobacter spp., (45%) isolates produced AmpC β-lactamase. In P. aeruginosa, it was seen to be produced by 20.1% isolates, in K. pneumoniae by 25.7% isolates, and in C. freundii it was seen to be produced by 64.2% isolates. The ESBL production was highest in case of E. coli (98%). It was also produced by 63.8% of Enterobacter spp. isolates, 15.9% of C. freundii and 12.2% of K. pneumoniae isolates. The MBL production was maximum in case of P. aeruginosa (25.9%). In case of Acinetobacter spp., it was 19.9% and in K. pneumoniae only 7.8% isolates produced MBL.
Almost all the pathogens were multidrug resistant and in all the isolates resistance was due to presence of ESBL, MBL, AmpC β lactamase. Thus, the intensivists can choose the antibiotics based on the bacteriological review of management of VAP. This study has shown that it is helpful in diagnosis of ventilator associated pneumonia and early specific treatment of these patients.