RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES

BANGALORE, KARNATAKA

ANNEXURE-II

SYNOPSIS FOR REGISTRATION OF SUBJECTS FOR

DISSERTATION

1. NAME OF THE CANDIDATE AND ADDRESS
/ DR. AMIT KHELGI
DEPT. OF MICROBIOLOGY
M.S. RAMAIAH MEDICAL COLLEGE
MSRIT POST
BANGALORE- 560054
2. NAME OF THE INSTITUTION / M.S. RAMAIAH MEDICAL COLLEGE
BANGALORE-560054
3. COURSE OF STUDY AND SUBJECT / M.D.(MICROBIOLOGY)
4. DATE OF ADMISSION TO COURSE / 31st MAY, 2011
5. TITLE OF THE TOPIC / “BACTERIOLOGICAL PROFILE OF VENTILATOR ASSOCIATED PNEUMONIA IN A TERTIARY CARE HOSPITAL WITH SPECIAL REFERENCE TO MULTI DRUG RESISTANT PATHOGENS”

6. BRIEF RESUME OF THE INTENDED WORK

6.1 Need for study

Ventilator associated pneumonia (VAP) is an important infection most often encountered in mechanically ventilated patients in intensive care units of the hospital. VAP occurs in approximately 9-24%of patients who are intubated.1The morbidity and mortality associated with VAP is more despite recent advances in diagnosis and accuracy of management.

The etiological agents of VAP and its severity vary with different patient populationsand the protocols adaptedin the ICU’s. Therefore, the study of the local microbial flora causing VAPand their susceptibility patterns in each hospital set up needs to be ascertained to guide more effective and rational utilization of antimicrobial agents.

The purpose of the present study is to detect the bacteria commonly causing VAP in ICUsof M.S. Ramaiah medical college and hospitaland to determine their antibiotic susceptibility patterns with emphasis on multidrug resistant pathogens.

6.2 Review of literature

Ventilator associated pneumonia is defined as pneumonia occurring in patients admitted to critical care units for more than 48 hours after endotracheal intubation and initiation of mechanical ventilation, including pneumonia developing even after extubation.1

In patients admitted to critical care units and mechanically ventilated the rates of VAPrange from 9 to 27% with the presence of multidrug resistant pathogens and high morbidity and mortality rates.VAP increases length of ICU stay by 28% and also increases the cost of treatment.2

A study by Joseph et al1 showed that early onset VAP, which occurs during 96 hours of mechanical ventilation usually is less severe, associated with a better prognosis and is more likely to be caused by antibiotic sensitive bacteria. Late onset VAP, which develops after 96 hours of mechanical ventilation is caused by multidrug resistant pathogens and is moreoften fatal.1,3,4

Dey A and Bairy I in their study showed that VAP is caused by various agents. Most common pathogens causing VAP are Acinetobacterspp(48.74%),Pseudomonas aeruginosa(25.53%), Escherichia coli(10.64%), Klebsiellapneumoniae(12.7%).5There is an increase in the drug resistance of these etiological agents recently.Pseudomonas spp, Acinetobacterspp and even Enterobacteriaceae are quite often multi drug resistant due to production of Extended Spectrum Beta Lactamases(ESBL), AmpC beta lactamases or Metallo BetaLactamases(MBL)1,5

6.3Objectivesof the study

  1. To isolate the bacterial pathogens causingVAP.
  2. To determine the antibiotic susceptibility pattern of the isolates
  3. To detect the presence of ESBL, AmpC beta lactamase, carbapenemase and MBL production in VAP pathogens.

7. MATERIALS AND METHODS

7.1 Source of data

Samples will be collected from the patients admitted into ICU of M.S.RamaiahHospital and put on mechanical ventilation for more than 48 hours.

Duration of study

January 2012 to December 2012 (12 months)

Inclusion criteria

  1. Patients admitted and put on mechanical ventilation for 48 hours in ICU’s of

M.S. Ramaiah medical college and hospital.

Exclusion criteria

  1. Age <12 years.
  2. Patients diagnosed to have lower respiratory infections like pulmonary tuberculosis, chronic obstructive pulmonary disease, acute respiratory distress syndrome, bronchial asthmaetc on admission.
  3. Patients with pneumonia prior to mechanical ventilation or within 48 hours of mechanical ventilation.

7.2 Method of collection of data

Study design- Cross-sectional study

Sample size-

Pooled analysis of average number of patients in Intensive care units on ventilator for more than 48hrs duration from similar tertiary care institutes and retrospective analysis of similar patients in our set up revealed a mean of 10 such patients per month.

Considering that the present study has been planned for a duration of 1year and assuming a 15% non-compliance/refusal, a sample size of 102 patients has been planned for inclusion in the study.

Statistical analysis of data-

The quantitative parameters suggesting age of patient, duration of stay etc. will be summarized in terms of descriptive statistics such as mean(±SD), median (Inter Quartile Range). Proportion of patients developing VAP will be estimated along with 95% confidence interval. To find out the statistical significance for difference observed in VAP between different populationgroups, Chi-Square test of significance will be employed. Level of significance shall be fixed at 5%. Similar kind of analysis will be carried out for various organisms that are isolated.

Study method-

Patients put on mechanical ventilator for >48hours and clinically suspected for pneumonia will be assessed by the modified clinical pulmonary infection score (CPIS)and those patients with CPIS score >6 will be diagnosed as having VAP.3

Endotracheal aspirates will be collected aseptically from the cases into a sterile container and taken to laboratory.

All samples will be processed as follows:

  1. Direct Gram stain smear examination of the sample.6
  2. Semi-quantitative culture methods on media like nutrient agar, MacConkey’s agar , blood/ chocolate agar.6
  3. The isolates will then be subjected to standard biochemical tests for identification.6
  4. Antibiotic susceptibility testing will be performed by Kirby-Bauer standard disc diffusion methodon Muller-Hinton agar for all the isolates. Antibiotics used will be according to CLSI guidelines.7
  5. Multi drug resistant pathogens will then be subjected to following tests for enzyme production
  6. Combination disc method for ESBL production.8
  7. Modified Hodge test for carbapenemase production.9
  8. EDTA disc synergy test for MBL production.9
  9. AmpC disc test for AmpC beta lactamase production.10

7.3 Does the study require any investigations or interventions to be conducted on patients or animals?

Yes.(Details in 7.2) above mentioned test are routinely done in the laboratory and the cost of these tests will not be bared by the patients.

7.4 Has ethical clearance been obtained from your institution in case

of 7.3?

Yes. (Certificate enclosed)

8.LIST OF REFERENCES:

  1. Joseph NM, Sisttla S, Dutta TK et al. “Ventilator associated pneumonia in a tertiary care hospital in India- role of multidrug resistant pathogens” J Infect DevCtries2010;4(4):218-225
  1. Wagh H and Acharya D.“Ventilator associated pneumonia-an overview” Br J Med Pract 2009;2(2):16-19
  1. Mandell LA, Wunderink R. “Pneumonia” Harrison’s principles of internal medicine, 17th edition, New York: McGraw-Hill 2008;2: 1619-1628
  1. Niederman MS and Craven DE. “ Guidelines for the management of adults with hospital-acquired ventilator associated and healthcare-associated pneumonia” Am J RespCrit Care Med 2005;171: 388-416
  1. Dey A and Bairy I. “ Incidence of multidrug resistant organisms causing ventilator-associated pneumonia in tertiary care hosipital:A nine months prospective study” Ann Thorac Med 2007;2:52-57
  1. Collee JG, Miles RS, Watt B. “Test for the identification of bacteria” Mackie and McCartney practical medical microbiology, 14th edition, New York: Churchill Livingstone 2006: 131-150
  1. Clinical Laboratory Standards Institute “Performance standard for antimicrobial disk susceptibility tests. Approved standard, 9th edition. CLSI document M2-A9. CLSI: Wayne, PA
  1. Thomson KS and Sanders CC. “Detection of Extended Spectrum Beta- Lactamases in members of the family Enterobacteriacae:comparison of the double-disk and three-dimensional test” Antimicrob Agents Chemother 1992;36: 1877- 1882
  1. Lee K, Chong Y, Shin HB et al. “ Modified Hodge and EDTA disk synergy tests to screen metallo-beta-lactamase-producing strains of Pseudomonas and Acinetobacter species” ClinMicrobiol Infect 2001;7: 88-91
  1. Singhal S, Mathur T, Khan S et al. “ Evaluation of methods for AmpC beta-lactamase in Gram negative clinical isolates from tertiary care hospitals” Indian J Med Microbiol2005;23: 120-124

9. SIGNATURE OF THE CANDIDATE
10.REMARKS OF THE GUIDE / The present study will be helpful in detecting the common bacterial pathogens associated with ventilator associated pneumonias in the intensive care units of the hospital and contribute towards early diagnosis and better prognosis in this group of patients.
11.1 NAME AND DESIGNATION OF THE GUIDE / DR A.G.PRATHAB
PROFESSOR- MICROBIOLOGY
M.S.RAMAIAH MEDICAL COLLEGE
BANGALORE
11.2 SIGNATURE OF THE GUIDE
11.3 HEAD OF THE DEPARTMENT / DR.P.R.SREENIVASA BABU
PROFESSOR& H.O.D – MICROBIOLOGY
M.S.RAMAIAH MEDICAL COLLEGE BANGALORE
11.4 SIGNATURE OF THE H.O.D
12.1 REMARKS OF THE CHAIRMAN AND PRINCIPAL
12.2 SIGNATURE OF THE PRINCIPAL

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