Ventilator-associated pneumonia: Incidence, risk factors, outcome, and microbiology

doi:10.1053/jcan.2003.4

Journal of Cardiothoracic and Vascular Anesthesia

Volume 17, Issue 1, February 2003, Pages 22-28

https://doi.org/10.1053/jcan.2003.4 Get rights and content

Abstract

Objective: To determine the incidence, risk factors, outcome, and pathogens of ventilator-associated pneumonia (VAP) in a cardiac surgical intensive care unit (ICU). Design: Prospective study. Setting: Escorts Heart Institute and Research Centre, New Delhi, India. Participants: Nine hundred fifty-two consecutive patients undergoing cardiac operations who received intermittent positive-pressure ventilation (IPPV). Interventions: All patients were assigned into VAP (n = 25) and non-VAP (n = 927) groups. Measurement and Main Results: Risk factors and other variables were analyzed with univariate and multivariate analysis. Of the 952 patients studied, 25 (2.6%) had VAP. On univariate analysis, significant risk factors were emergency surgery, chronic obstructive pulmonary disease (COPD), reintubation, coma, steroid treatment, intra-aortic balloon counterpulsation (IABC), enteral feedings, tracheostomy, acute physiology, age, and chronic health evaluation (APACHE II) score, prior antibiotics, and IPPV hours. On multivariate analysis, IPPV hours (153.75 ± 114.44 v 19.65 ± 7.99; p < 0.001) and steroids (20% v 0%; p < 0.001) were independent predictors of VAP. The most common pathogens isolated were Pseudomonas aeruginosa (22), Escherichia coli (10), Klebsiella pneumoniae (4), Staphylococcus species (4), and Acinetobacter species (2). The mortality rate in VAP was 16% as compared with 0.2% in non-VAP cases (p < 0.001). Conclusion: These data suggest that by univariate analysis the risk factors for VAP were emergency surgery, COPD, reintubation, coma, steroid treatment, IABC, enteral feedings, tracheostomy, APACHE II score, prior antibiotics, and IPPV hours. On multivariate analysis, only IPPV hours and steroids were independent predictors of VAP. Pseudomonas aeruginosa is the most common pathogen associated with VAP, and the mortality is increased with VAP. Copyright 2003, Elsevier Science (USA). All rights reserved.

Section snippets

Materials and methods

Approval of the institutional review board and informed consent from the patient were obtained for this prospective study conducted at Escorts Heart Institute and Research Centre between July 27, 2001, and October 31, 2001, to determine the incidence, risk factors, outcome, and pathogens of VAP in the cardiac surgical ICU. During this period, 952 adult patients who were undergoing cardiac operations and were admitted to the ICU on IPPV were included in this prospective study. They consisted of

Results

Of 952 patients in the study, 25 (2.6%) had VAP. The mean interval between admission to the ICU and the diagnosis of VAP was 4.5 ± 2.8 days. The median interval was 4 days. More than 90% of VAP cases occurred within 10 days of admission to the ICU.

Table 1 shows the results from the univariate analysis for 8 variables that were not significantly associated with VAP.

. Comparison of VAP and non-VAP cases (univariate analysis)

Variable	VAP (n = 25)	Non-VAP (n = 927)	p Value
Age (y)	59.7 ± 12.7	56.5 ± 10.7	NS

Discussion

The authors investigated the incidence, risk factors, outcome, and pathogens of VAP in the cardiac surgical ICU. The estimated prevalence of nosocomial pneumonia in intensive care units ranges from 10% to 65% with mortality rates of 13% to 55%.¹ Nosocomial pneumonia was diagnosed in 25 (2.6%) of the 952 patients in this study. The incidence of 2.6% in cardiothoracic patients is comparable to that reported in another study.⁶ The supine position of mechanically ventilated patients increases the

Acknowledgements

The authors thank S. Shekhawat for statistical analysis and R. Mathew for secretarial assistance.

References (30)

MH Kollef et al.
A randomized clinical trial of continuous aspiration of subglottic secretions in cardiac surgery patients
Chest
(1999)
P Castelli et al.
Intra-aortic balloon counterpulsation: outcome in cardiac surgical patients
J Cardiothorac Vasc Anesth
(2001)
R Celis et al.
Nosocomical pneumonia: A multivariate analysis of risk and prognosis
Chest
(1988)
AS Cross et al.
Role of respiratory assistance devices in endemic nosocomial pneumonia
Am J Med
(1981)
MH Kollef et al.
Patient transport from intensive care increases the risk of developing ventilator associated pneumonia
Chest
(1997)
R Celis et al.
A nosocomical pneumonia in a multivariate analysis of risk and prognosis
Chest
(1988)
MH Kollef et al.
Ventilatior-associated pneumonia: clinical consideratins
AJR Am J Roentgenol
(1994)
American College of Chest Physicians Society of Critical Care Medicine Consensus Conference
Definition for sepsis and organ failure and guidelines for the use of innovative therapies in sepsis
Crit Care Med
(1992)
D Baxby et al.
Selective decontamination of the digestive tract: 13 years on, what it is and what it is not
Intensive Care Med
(1996)
AM Ziad et al.
The incidence and risk factors of ventilator associated pneumonia in a Riyadh Hospital
Infection control and hospital epidemiology.
(2000)

S Sim et al.

Ventilator-associated pneumonia in a cardiothoracic surgery centre, postoperative intensive care unit

J Hosp Infect

(2001)

MH Kolleff

Ventilator-associated pneumonia: A multivariate analysis

JAMA

(1993)

JY Fagon et al.

Nosocomial pneumonia and morbidity among patients in intensive care units

JAMA

(1996)

L Papazian et al.

Effect of ventilator associated pneumonia on mortality and morbidity

Am J Respir Crit Care Med

(1996)

HL New

Infection problems for the 1990's. Do we have an answer?

Scand J Infect Dis

(1993)

Cited by (86)

Multinational prospective cohort study over 18 years of the risk factors for ventilator-associated pneumonia in 9 Asian countries: INICC findings
2023, American Journal of Infection Control
Ventilator associated pneumonia (VAP) rates in Asia are several times above those of US. The objective of this study is to identify VAP risk factors.
We conducted a prospective cohort study, between March 27, 2004 and November 2, 2022, in 279 ICUs of 95 hospitals in 44 cities in 9 Asian countries (China, India, Malaysia, Mongolia, Nepal, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam).
153,717 patients, followed during 892,996 patient-days, acquired 3,369 VAPs. We analyzed 10 independent variables.
Using multiple logistic regression we identified following independent VAP RFs= Age, rising VAP risk 1% per year (aOR=1.01; 95%CI=1.00-1.01, P<.0001); male gender (OR=1.17; 95%CI=1.08-1.26, P<.0001); length of stay, rising VAP risk 7% daily (aOR=1.07; 95%CI=1.06-1.07, P<.0001); mechanical ventilation (MV) device utilization (DU) ratio (OR=1.43; 95%CI=1.36-1.51; p<.0001); tracheostomy connected to a MV (OR=11.17; 95%CI=9.55-14.27; p<.0001); public (OR=1.84; 95%CI=1.49-2.26, P<.0001), and private (OR=1.57; 95%CI=1.29-1.91, P<.0001) compared with teaching hospitals; upper-middle income country (OR=1.86; 95%CI=1.63-2.14, P<.0001). Regarding ICUs, Medical-Surgical (OR=4.61; 95%CI=3.43-6.17; P<.0001), Neurologic (OR=3.76; 95%CI=2.43-5.82; P<.0001), Medical (OR=2.78; 95%CI=2.04-3.79; P<.0001), and Neuro-Surgical (OR=2.33; 95%CI=1.61-3.92; P<.0001) showed the highest risk.
Some identified VAP RFs are unlikely to change= age, gender, ICU type, facility ownership, country income level. Based on our results, we recommend limit use of tracheostomy, reducing LOS, reducing the MV/DU ratio, and implementing an evidence-based set of VAP prevention recommendations.
Treatment of MRSA infections in India: Clinical insights from a Delphi analysis
2022, Indian Journal of Medical Microbiology
International and Indian guidelines for the management of patients with methicillin-resistant Staphylococcus aureus (MRSA) infections are available, but the local guidelines are not MRSA-specific. This study aimed to provide clinical insights for the treatment of MRSA infections in India.
We used a three-step modified Delphi method to obtain insights. Ten experts comprising infectious disease specialists, microbiologists, pulmonologists, and critical care experts agreed to participate in the analysis. In round 1, a total of 161 statements were circulated to the panel and the experts were asked to ‘agree’ or ‘disagree’ by responding ‘yes’ or ‘no’ to each statement and provide comments. The same process was used for 73 statements in round 2. Direct interaction with the experts was carried out in round 3 wherein 35 statements were discussed. At least 80% of the experts had to agree for a statement to reach concordance.
Eighty-eight statements in round 1, thirty-eight statements in round 2, and eight statements in round 3 reached concordance and were accepted without modification. The final document comprised 152 statements on the management of various syndromes associated with MRSA such as skin and soft tissue infections, bacteremia and endocarditis, pneumonia, bone and joint infections, and central nervous system infections.
This analysis will assist clinicians in India to choose an appropriate course of action for MRSA infections.
Relationship of various infection control interventions to the prevalence of multidrug-resistant Pseudomonas aeruginosa among U.S. hospitals
2016, American Journal of Infection Control
Health care–associated infections caused by antibiotic-resistant gram-negative bacteria, such as Pseudomonas aeruginosa, are an emerging and increasingly important public health threat. However, there are very few studies that examine the relationships between antimicrobial resistance strategies and interventions and the prevalence of antibiotic-resistant and multidrug-resistant strains of Pseudomonas.
The membership of the Association for Professionals in Infection Control and Epidemiology was invited to participate in a Web-based survey of U.S. acute care hospital infection preventionists.
A final sample of 225 completed responses was analyzed using correlational techniques. Resistance to gentamicin (r = 0.17, P = .01), imipenem (r = 0.18, P = .02), ceftazidime (r = 0.20, P = .03), and ciprofloxacin (r = 0.15, P = .03) all showed significant direct associations with epidemiologic investigation using molecular testing. A significant inverse relationship was found between resistance to ceftazidime and effective efforts in the identification and isolation of infected patients (r = −0.18, P = .02).
The finding of significant direct relationships between antimicrobial resistance and epidemiologic investigations using molecular testing suggests that the increased burden of resistance is associated with molecular testing rather than the intervention driving down rates. Effective identification and isolation of infected patients appeared to be associated with lower resistance rates. Further research is needed to uncover causal relationships.
Liquid and vapor-phase vinegar reduces Klebsiella pneumoniae onfresh coriander
2015, Food Control
Citation Excerpt :
K. pneumoniae belongs to the same family of Enterobacteriaceae as E. coli and is found widely in the environment and also in the intestinal tracts of mammals. It can cause many diseases such as ventilator-associated pneumonia (Pawar et al., 2003), septicemia and various soft-tissue infections (Yang, Lauderdale, & Lo, 2004). Virtually, no reports exist on the incidence of K. pneumoniae on coriander, but there are reports of contamination by this bacterium on other foods such as in orange juice concentrate (Fuentes, Hazen, López-Torres, & Rechani, 1985), dried bush okra and African spider herb (Mpuchane & Gashe, 1996), on a hamburger in Houston, Texas (Sabota et al., 1998), raw and ready-to-eat foods from restaurants in Spain (Soriano, Rico, Moltó, & Mañes, 2001), fruit juices sold in Tripoli–Libya (Ghenghesh, Belhaj, El-Amin, El-Nefathi, & Zalmum, 2004) and street foods sold in Malaysia (Haryani et al., 2007).
Samples of fresh coriander were sourced from several markets in the Ladkrabang and Minburi areas of Bangkok, Thailand. These were examined in the laboratory for fecal coliform contamination. The bacterium Klebsiella pneumoniae was the predominant contaminant in 48.5–84.0% of the 30 samples tested. Inhibition of surface contaminations of K. pneumoniae by vinegar was measured in vitro for either liquid- or vapor-phase exposures. For liquid-phase exposure, levels above 2.4% (v/v) acetic acid (AA) completely inhibited K. pneumoniae. After 50 min of vapor-phase exposure, 8% AA completely inhibited K. pneumoniae spread on Mueller Hilton agar (4.10 ± 0.04 log CFU/ml, 30 ± 2 °C, 80 ± 2% RH). Reduction of K. pneumoniae contamination on fresh coriander leaves using vinegar vapor was also examined. The effectiveness of inhibition was related to the level of K. pneumoniae inoculation, with vinegar vapor being shown to be an effective control agent for surface contaminations on fresh coriander so reducing the potential health risks to consumers.
Incidence and attributable costs of ventilator-associated pneumonia (VAP) in a tertiary-level intensive care unit (ICU) in northern India
2015, Journal of Infection and Public Health
Citation Excerpt :
Among the patients who developed VAP infections, the length of stay in the ICU was nearly three-fold greater, and the total hospital stay was double the duration of the patients who did not develop VAP infections. These findings confirm the results of numerous other studies that have shown that the development of nosocomial pneumonia leads to prolonged hospital stays [17–20]. Among our patients, the high incidence of MDR organisms that caused VAP infections probably contributed to the prolonged stays because these infections took longer to treat and generally resulted in poorer courses in the ICU.
Ventilator-associated pneumonia (VAP) is the most common nosocomial infection acquired by patients in the intensive care unit (ICU). However, the economic effects of such infections remain unclear particularly in developing countries.
Patients who were mechanically ventilated for more than 48 h in the ICU were studied for the occurrence of VAP. Total drug costs and hospital costs were noted, and attributable costs were calculated after adjusting for potential confounders.
Ninety-five (38%) patients who were ventilated for more than 48 h developed VAP, which resulted in an incidence of 40.1 VAP infections/1000 mechanical ventilation days. The patients with VAP experienced significantly longer hospital stay [21 (IQ = 14–33) days versus 11 (IQ = 6–18) days, P < 0.0001)] and incurred greater hospital costs [USD $6250.92 (IQ = 3525.39–9667.57) versus $2598.84 (IQ = 1644.33–4477.65), P < 0.0001]. Multiple regression analysis revealed that the cost-driving factors in our study population were the occurrence of VAP infections (P < 0.0001) and the duration of hospital stay (P < 0.0001). The attributable cost of VAP infection was calculated to be USD $5200 (95% CI = 3245–7152).
We conclude that VAP significantly increases the costs of treatment in low-income developing countries. This study highlights the need to implement urgent measures to reduce the incidence of this disease in ICUs.
Ventilator-associated pneumonia after cardiac surgery: A meta-analysis and systematic review
2014, Journal of Thoracic and Cardiovascular Surgery
Ventilator-associated pneumonia (VAP) is the most common and serious nosocomial infection that threatens patients who have undergone cardiac surgery. This article summarizes its clinical characteristics and provides theoretical evidence for prevention and treatment.
A literature search was conducted using PubMed, Embase, the Cochrane Library, and Web of Knowledge databases and by manual search. Data involving the prevalence, etiology, risk factors, or clinical outcomes were extracted for systematic review and meta-analysis.
Eleven studies on VAP after cardiac surgery were included. When the results were merged the VAP rate was 21.27/1000 ventilator-days. The prevalence reached 6.37% of all patients and 35.2% of patients who were on mechanical ventilation for more than 48 hours. Among the isolated pathogens, Pseudomonas aeruginosa had the highest detection rate, with an average of 23.19%, followed by Staphylococcus aureus (20.15%), Haemophilus influenzae (19.53%), Acinetobacter baumannii (10.68%), Escherichia coli (10.18%), Klebsiella pneumoniae (9.52%), and Candida albicans (7.20%). Risk factors were also analyzed. We found that New York Heart Association cardiac function class IV, pulmonary hypertension, chronic obstructive pulmonary disease, peripheral vascular disease, renal disease, emergency surgery, intra-aortic balloon counterpulsation, cardiopulmonary bypass time, aortic crossclamp time, mechanical ventilation time, reintervention, and reintubation were closely related to the occurrence of VAP; there was no association with gender and diabetes mellitus. Once patients had VAP, mortality and length of stay in the intensive care unit were significantly increased.
VAP in patients after cardiac surgery is common and has a poor prognosis. It is mainly caused by gram-negative bacteria, and could be affected by a series of factors.

View all citing articles on Scopus

^*: Address reprint requests to Yatin Mehta, MD, DNB, FRCA, FAMS, Department of Anaesthesiology, Escorts Heart Institute and Research Centre, New Delhi 110 025, India. E-mail: [email protected]

View full text

Original ArticlesVentilator-associated pneumonia: Incidence, risk factors, outcome, and microbiology*

Abstract

Section snippets

Materials and methods

Results

Discussion

Acknowledgements

Chest

J Cardiothorac Vasc Anesth

Chest

Am J Med

Chest

Chest

Ventilatior-associated pneumonia: clinical consideratins

AJR Am J Roentgenol

Definition for sepsis and organ failure and guidelines for the use of innovative therapies in sepsis

Crit Care Med

Selective decontamination of the digestive tract: 13 years on, what it is and what it is not

Intensive Care Med

The incidence and risk factors of ventilator associated pneumonia in a Riyadh Hospital

Infection control and hospital epidemiology.

Ventilator-associated pneumonia in a cardiothoracic surgery centre, postoperative intensive care unit

J Hosp Infect

Ventilator-associated pneumonia: A multivariate analysis

JAMA

Nosocomial pneumonia and morbidity among patients in intensive care units

JAMA

Effect of ventilator associated pneumonia on mortality and morbidity

Am J Respir Crit Care Med

Infection problems for the 1990's. Do we have an answer?

Scand J Infect Dis

Original Articles
Ventilator-associated pneumonia: Incidence, risk factors, outcome, and microbiology*