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PAPERS PRESENTED AT THE XVII ANNUAL CONFERENCE OF HOSPITAL INFECTION |
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Year : 2021 | Volume
: 9
| Issue : 3 | Page : 69-76 |
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Surveillance of device-associated infections at a tertiary care hospital of Punjab
Veenu Gupta, Sarit Sharma, Ashwani Chaudhary, Jyoti Chaudhary, PL Gautam
Departments of Microbiology, Community Medicine, Neuro Surgery, Critical Care Medicine, Dayanand Medical College and Hospital, Ludhiana, Punjab, India
Date of Submission | 16-Apr-2022 |
Date of Acceptance | 01-May-2022 |
Date of Web Publication | 22-Jul-2022 |
Correspondence Address: Dr. Veenu Gupta Department of Microbiology, Dayanand Medical College and Hospital, Ludhiana, Punjab India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/jpsic.jpsic_18_22
Background: Surveillance of health-care-associated infections (HAIs) plays a key role in the hospital infection control programme and reduction of HAIs. Device-associated infections (DAIs) are an important cause of excessive stay and mortality. The prevalence of HAIs is underreported from developing nations due to a lack of systematic surveillance. Aims and Objectives: The aim of the study was to know the rate and microbiological profile of DAIs. Materials and Methods: This surveillance study was conducted over a period of 2 years. Patients with indwelling devices were included. The data were collected and analysed by infection control team and labelled DAIs as per the CDC guidelines. The rates of HAIs and the profile of pathogens isolated were analysed. Results: A total of 294 patients developed DAIs, of which 181 were male and 113 were female. A total of 239 device-associated infections were reported in 2019 and 55 in 2020 and overall rate of DAIs was 1.81 and 0.58/1000 device days, respectively. Among DAIs, 50 were ventilator-associated pneumonia (VAP), 71 central line-associated bloodstream infections (CLABSI) and 173 catheter-associated urinary tract infection (CAUTI) cases. Overall, the rate was 2.02,1.21,1.21/1000 device days for VAP, CLABSI and CAUTI, respectively. In DAI's, majority were males and maximum cases developed after 6–10 days, 15 days and 11–15 days of device use in VAP/CAUTI and CLABSI, respectively. Gram-negative isolates (85.1%) were predominant, and among these, most common were Klebsiella spp, Acinetobacter spp and Escherichia coli. A high rate of multidrug resistance was observed. Conclusions: The present surveillance shows high resistance pattern of Gram-negative organisms causing DAIs. To reduce the risk of infection in hospitalised patients, DA-HAI surveillance is of primary importance as it helps in implementing preventive measures.
Keywords: Catheter-associated urinary tract infection, central line-associated bloodstream infection, device-associated health care-associated infections, ventilator-associated pneumonia
How to cite this article: Gupta V, Sharma S, Chaudhary A, Chaudhary J, Gautam P L. Surveillance of device-associated infections at a tertiary care hospital of Punjab. J Patient Saf Infect Control 2021;9:69-76 |
How to cite this URL: Gupta V, Sharma S, Chaudhary A, Chaudhary J, Gautam P L. Surveillance of device-associated infections at a tertiary care hospital of Punjab. J Patient Saf Infect Control [serial online] 2021 [cited 2023 Feb 9];9:69-76. Available from: https://www.jpsiconline.com/text.asp?2021/9/3/69/351737 |
Introduction | |  |
Healthcare-associated infections (HAIs) are one of the most common and preventable patient safety problems in the world; at any given time, HAIs affect over 1.4 million people worldwide. The majority of HAIs are caused by indwelling devices, causing device-associated infections (DAIs) such as ventilator-associated pneumonia (VAP), central line-associated bloodstream infections (CLABSI) and catheter-associated urinary tract infections (CAUTIs)[1],[2]
Device-associated health care-associated infections (DA-HAIs) affect the quality of health care in terms of increased morbidity, mortality and additional cost for patient care provision. DA-HAIs pose a severe threat to patients, despite prevention efforts that have resulted to a significant decrease of infections' incidence.[3],[4],[5],[6],[7]
Interaction between bacterial characteristics, device-related factors and host factors plays an important role in acquiring DA-HAIs. In modern times, the risk of getting infected with resistant Gram-negative infections has increased because of more extensive use of invasive devices, poor hospital infection control policies and admission of sicker patients who are already immunocompromised and are at even higher risk for infection.[8] In a study, it was observed among patients with DA-HAI, 95% of cases of UTI were CAUTI, 87% of cases of BSI had bloodstream infection originate from an indwelling vascular catheter, and 86% of hospital-acquired pneumonia cases had ventilator-associated pneumonia.[8] Another study highlighted that DA-HAIs concern nearly one-fourth of intensive care unit (ICU) patients and infection rates worldwide also vary with respect to geographic region, economic status of country and type of hospital facility.[9]
This signifies that monitoring hospital-acquired infections is one of the most important elements in the prevention and control of device-associated health-care-associated infections (DA-HAIs). Studies have shown that surveillance and monitoring can lead to DA-HAIs reduction if implemented stringently.[10],[11]
Surveillance of HAIs/DAIs helps in generating baseline data, understanding the rates and trends over time and in the implementation of preventive measures, the effects of which can also be ascertained over time through continuous surveillance.[12] Surveillance of HAIs plays a key role in the hospital infection control programme and reduction of HAIs. DAIs-HAIs are an important cause of excessive stay and mortality, but the incidence of HAIs is underreported from developing nations due to a lack of systematic surveillance
Aims and objectives
The aim of the study was to know the incidence and microbiological profile of DA-HAIs in a tertiary care hospital.
Materials and Methods | |  |
Study design
A retrospective surveillance study was conducted over a period of 2 years (January 2019–December 2020) in tertiary care hospital.
Study area
The study was conducted in a 1600-bedded tertiary care hospital which mostly caters to patients from Punjab and other neighbouring states of North India. Hospital also has 120 bedded ICU block where critically ill patients are admitted. Hospital has 24 h × 7 h working Microbiology laboratory and infection control department.
Study participants and inclusion criteria
All patients with indwelling devices were included and the samples were sent for testing if there is clinical suspicion of DA-HAI.
Definitions
Definitions for device-associated infections followed were those as mentioned in Hospital Infection Control Manual which in turn are based on standard National Healthcare Safety Network (NHSN) by Centre for Disease Control, Atlanta, USA.[1],[13]
Infection control policy
Infection prevention bundles for VAP, CAUTI and CLABSI are practiced diligently, and all the health-care staff are trained in infection control practices. During infection control rounds, Infection Control Nurses observe the practices of health-care staff and submit their daily report. Training sessions are arranged where noncompliance with infection control practices is noted. The admitted patients are followed from 2 calendar days after insertion of device till 2 calendar days after the removal of the device/discharge from the ward/ICUs/high-dependency units etc., to detect device associated infections acquired in hospital. On categorisation into DA-HAIs (VAP, CAUTI and CLABSI), informed to primary department is informed for further action and treatment. In case of CAUTI and CLABSI, the need for device is assessed and if still needed, it is changed with a new device taking all aseptic precautions. In case of VAP, antibiotics are reviewed, and infection control practices are ensured.
Microbiological analysis
The microbiological processing of specimens was done using the standard methods.[14] The identification of all microbial isolates was done by the Vitek-2 system (Biomeriux, France) using ID GP/GN/YST cards. The antimicrobial susceptibility testing was done by the Vitek-2 susceptibility system (Biomeriux Pvt Ltd). Only those pathogens associated with nosocomial infections that met the CDC criteria were included. The profile of pathogens isolated was analysed.
Data collection
Data were collected by carefully scrutinising the records of Infection Control, Microbiology and from hospital information system for the years 2019 and 2020. Data collected included relevant patients' demographics, date and site of DA-HAIs onset, duration of device usage (days), isolated pathogens, antibiogram results and patient outcome on discharge were recorded by infection control nurses, analysed by infection control team and labelled DA-HAIs as per CDC guidelines.[13],[14] The rates of DAIs were calculated. Statistical analysis was done using percentages and proportions and the Chi-square test.
Results | |  |
Rate of DAIS: a total of 64,263 patients were on device accounting for total of 225,908 device days, in 2 years out of which 294 patients developed DAIs with overall infection rate 0.45% and DAI rate 1.3/1000 device days. In 2019, A total of 48,013 patients were on device accounting for total of 131,627 device days, out of which 239 patients developed DAIs with DAI rate of 1.8/1000 device days. In 2020, a total of 16,250 patients were on device accounting for total of 94,281 device days, out of which 55 patients developed DAIs with DAI rate of 0.58/1000 device days [Table 1].
Among 294 DAIs, 50 were VAP (17%), 71 were CLABSI (24.1%) and 173 were CAUTI (58.8%) cases making CAUTI the most common device-associated infection. The overall rate was 2.02, 1.21, 1.21/1000 device days for VAP, CLABSI and CAUTI, respectively. The rates of VAP, CLABSI and CAUTI per 1000 device days were 2.84, 1.51 and 1.74 in 2019 and 0.8, 0.78, 0.46 in 2020 [Table 2]. | Table 2: Year-wise rate of ventilator-associated pneumonia/catheter-associated urinary tract infection/central line-associated bloodstream infection
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Demographic profile and outcome of device-associated infections
Among 294 patients, 181 were male and 113 were female. Sex and age-wise distribution of patients with DA-HAIs is shown in [Figure 1] and [Figure 2]. Relation of age with DA-HAI is variable. Although the rate of infections is higher in patients >40 years of age for VAP and CAUTI, whereas CLABSI rates are higher in younger population. VAP cases 58% were males and majority cases were in 51–60 years' age group. Among CAUTI cases, 56% were male and majority cases were in 51–60 years' age group followed by 21–30 years. Among CLABSI cases, 78% were male and majority cases were in <20 years' age group. A total of 86 (29.2%) patients had fatal outcome with higher mortality in VAP (66%) followed by CAUTI (23%) and CLABSI (16.9%). | Figure 1: Demographic profile of DAI cases (%) Device-associated infections
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 | Figure 2: Age-wise distribution of DAI cases. DAI: Device-associated infections
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Device use
Maximum VAP cases developed after 6–10 days of device use. Maximum CAUTI cases developed after 15 days of device use followed by 11–15 days. Maximum CLABSI cases developed after 11–15 days of device use [Figure 3]. | Figure 3: Correlation of device days with DAI cases. DAI: Device-associated infections
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Profile of organisms
A total of 303 microorganisms were obtained from 294 DA-HAIs. Monomicrobial growth was seen in 285 cases and in 9 CAUTI cases, two isolates were obtained. Gram-negative isolates (85.1%) were predominant followed by Gram positive (10.6%) and fungal isolates (4.3%), and among these, most common were Klebsiella, Acinetobacter spp and Escherichia More Details coli.
A total of 50 isolates were obtained from VAP cases, Klebsiella (46%) and Acinetobacter (40%) spp were common isolates. The microorganism showed multidrug resistance pattern, showing sensitivity to Polymyxin B and Tigecycline only [Figure 4] and [Figure 5]. | Figure 4: Distribution of isolates in VAP cases. VAP: Ventilator-associated pneumonia
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 | Figure 5: Antimicrobial resistance profile of common VAP isolates. VAP: Ventilator-associated pneumonia
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A total of 71 isolates were obtained from CLABSI cases; Klebsiella (32.3%), Acinetobacter (21.1%) and Candida spp (14%) were common isolates. Many isolates were resistant even to Polymyxin B, Carbapenems and Tigecycline [Figure 6] and [Figure 7]. | Figure 6: Distribution of isolates in CLABSI cases. CLABSI: Central line-associated bloodstream infections
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 | Figure 7: Antimicrobial resistance profile of common CLABSI isolates. CLABSI: Central line-associated bloodstream infections
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A total of 182 isolates were obtained from CAUTI cases; Klebsiella spp (25.8%), E coli (23.0%) and Proteus and Enterococcus spp (13.2% each) were common isolates. Isolates also followed a multidrug resistance pattern being resistant to cephalosporins, aminoglycosides and carbapenems [Figure 8] and [Figure 9]. | Figure 8: Distribution of isolates in CAUTI cases. CAUTI: Catheter-associated urinary tract infection
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 | Figure 9: Antimicrobial resistance profile of common CAUTI isolates. CAUTI: Catheter-associated urinary tract infection
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A high rate of multidrug resistance was observed in the isolates. For Gram-negative isolates, polymyxin and tigecycline and for Gram-positive vancomycin, teicoplanin and linezolid were most effective. The Candida isolates showed good susceptibility to azoles and Echinocandin antifungals.
Discussion | |  |
Surveillance and monitoring of device-associated infections in the hospital admitted patients can lead to DA-HAIs reduction if implemented with a systematic approach. This needs participation from all the departments who are sensitive to importance of preventive measures and a multidimensional hospital infection control committee.[9],[10]
A total of 64,263 patients were on device accounting for total of 225,908 device days, in 2 years out of which 294 patients developed DAIs. with overall infection rate 0.45% and DAI rate 1.3/1000 device days whereas high rate (12.6%, 5.3%, 4.65%) was observed in studies on surveillance of DAIs.[15],[16],[17]
Among 294DAIs in the present study, CAUTI was most common (58.8%) followed by CLABSI (24.1%) and VAP (17%). In contrast to our study, CLABSI (48.8%) was most common followed by VAP (37.2%) and CAUTI (14%) in a study by Iordanou et al.[15]
The rates of VAP in our study were higher in year 2019 (2.8/1000 ventilator days) than those reported by the NHSN (1.3/1000 ventilator days), but later in year 2020, it was lower 0.8/1000 ventilator days implying better infection control practices. It is also speculated due to COVID pandemic, the HCWs followed guidelines more stringently resulting in lower rates. The cumulative rates of CLABSIs in our study were slightly higher (1.21/1000 central line days) than those reported by the NHSN (1.1/1000 central line days), but the rates were lower in year 2020 than 2019. These rates were quite lower than the rates of CLABSI as mentioned in the WHO reports (12.2/1000 central line days) for low-resource countries. CAUTI rates in our study were higher (1.7/1000 catheter days) in year 2019 than benchmarks by NHSN (1.5/1000 catheter days), but CAUTI rates improved in year 2020.[18]
As per CDC-NNIS System reports, in the US, pooled mean rates of DAI for CAUTI were 3.9 per 1000 urinary catheter days, VAP – 5.4/1000 ventilator days and CLABSI – 4.0/1000 CVC days.[6] The rates in the present study are lower than the rates of VAP mentioned in a meta-analysis in some recent studies (8.9–40/1000 ventilator days).[19] Various studies in literature showed higher rates of VAP (12, 10.1, 20.8, 16.8, 11.8/1000 VDs,) CLABSI (9.8, 15.9, 3.1, 4.4, 7.4/1000 CLDs) and CAUTI (8.6, 2.7, 6.4, 17.8, 9.7/1000 CDs) as compared to our study.[12],[15],[16],[17],[20]
The prolonged use of devices is the single most important risk factor for developing DAIS. Maximum DAIs developed after 6–10 days for VAP, after 15 days of device use for CAUTI and 11–15 days of device use for CLABSI. Therefore, the focus during infection prevention practices should be to reduce duration of device use. VAP, CAUTI and CLABSI prevention bundles should be followed not in during insertion but also during device maintenance.[21]
In cases of DAIs, Gram-negative isolates (85.1%) were predominant followed by Gram positive (10.6%) and fungal isolates (4.3%), and among these, most common were Klebsiella, Acinetobacter spp and E. coli. which was concomitant with results from other studies.[22],[23] In a prospective study in New Delhi among DA-HAIs reported, Klebsiella spp (28.5%) followed by Enterococcus spp (24.4%) were common isolates.[20] Tao et al. in their study reported Acinetobacter baumannii (19.1%), followed by Pseudomonas aeruginosa (17.2%), Klebsiella pneumoniae (11.9%) and Staphylococcus aureus (11.9%) common isolates in DAIs.[16]
In the present study, the most common organisms were Klebsiella (46%) and Acinetobacter (40%) spp in VAP, Klebsiella spp (25.8%), E coli (23.0%), Proteus and Enterococcus spp (13.2% each) in CAUTI and Klebsiella spp (32.3%), Acinetobacter spp (21.1%) and Candida spp (14%) in CLABSI. The most common organisms causing VAE, CAUTI and CLABSI were Acinetobacter (40%), Enterococcus (35.4%) and Candida spp (26.3%), respectively, in study by Kumar et al.[20] In a study by Iordanou et al., P. aeruginosa (25%), C. albicans (25%) and A baumannii (12.5%) in VAP, S. epidermidis (25.6%) in CLABSI and C. albicans (33.3%) in CAUTI were prevalent.[15]
Most of the Gram-negative organisms were multidrug resistant; however, none of the isolates were colistin and vancomycin resistant, similar to reported in literature.[15],[17],[20] For Gram-negative isolates polymyxin and tigecycline and for Gram-positive vancomycin, teicoplanin and linezolid were most effective.
A total of 86 (29.2%) patients had fatal outcome with higher mortality in VAP (66%) followed by CAUTI (23%) and CLABSI (16.9%) similar to reported in literature where crude mortality rate for patients with VAP, CAUTI and CLABSI was 38.5%, 33.3% and 33.3%, respectively.[15] In another study, 39.2% patients with DAIs had fatal outcome[17]
Another point highlighted in the present study was that most of the Gram-negative microorganisms isolated showed multidrug resistance pattern not only to third-generation cephalosporins, aminoglycosides and carbapenems but to tigecycline and polymyxins also, which are relatively newer antimicrobial drugs. These bacterial infections pose a serious and rapidly emerging threat for hospitalised patients and present many challenges in treatment and cause increased length of stay, increased economic costs, greater morbidity and mortality. Only solution is prevention of HAIs including DA-HAIs by following best infection control practices and judicious use of antibiotics.[24],[25] It has been observed in several studies that HAIs preventive bundles are associated with DA-HAIs reduction.[21],[26] To reduce the risk of infection in hospitalised patients, DA-HAI surveillance is of primary importance as it helps in implementing preventive measures.[24],[25],[26],[27] However, we need to strengthen our preventive practices and use this data for action to reduce the rates of infections, mortality and antimicrobial resistance.
Conclusions | |  |
The present surveillance shows predominance of multidrug-resistant Gram-negative organisms causing DA-HAIs. Prolonged device use was important risk factor. The rates of DA-HAIs in our study were almost similar to NHSN. To reduce the risk of infection in hospitalised patients, DA-HAI surveillance is of primary importance as it helps in implementing preventive measures.
Acknowledgments
We acknowledge contribution of infection control nurses in surveillance of device-associated infections and Dr. Shruti Sharma Critical care Medicine in manuscript write up.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9]
[Table 1], [Table 2]
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