Central Line Associated Blood Stream Infection: Microbiological Profile and its Antimicrobial Susceptibility Pattern at Tertiary Care Centre

Central venous catheters are commonly inserted to monitor patients with critical illnesses. Even when used to treat very ill patients, they are susceptible to widespread headaches, including central line-associated bloodstream infections (CLABSI). Central line-associated bloodstream infection (CLABSI) is one of the most significant HAIs, associated with excess mortality of 12–25%. To discover CLABSI cases, microbiological profiles, and their antimicrobial susceptibility. The study was conducted in an intensive care unit over a period of 12 months. 150 blood samples and catheter tips were collected for the culture of suspected or secondary bacteremia. CLABSI is described as being consistent with the CDC's proposal. Automated VITEK 2 technology identifies bacterial isolates and investigates their antimicrobial susceptibility. Out of 150 samples, 50 showed no growth, 45 showed colonizers, 40 showed CLABSI, and 15 showed secondary infection. Fifty-five had positive blood cultures, 15 of whom had another source of infection. In our study, the CLABSI rate was 7.8/1000 central venous days. Rigorous implementation of the system and maintenance of the central line bundle are mandatory to prevent colonization.


INTRODUCTION
Central venous catheters (CVCs) are inserted in seriously ill patients.Its inevitable use makes patients more vulnerable to headaches, which consist of central line-related bloodstream infections (CLABSIs).The problem of CLABSIs has received increasing interest in recent years. 1 The prevention of CLABSI consists of the development of information, guidelines, package care, the most sterile barrier, the use of 2% chlorhexidine, early catheter elimination, and the use of antimicrobial catheters and antimicrobial catheter lock solution. 2he main objective of the present study was to determine the microbiological profile and antimicrobial susceptibility pattern of isolated bacteria from CLABSIs in an intensive care unit.Central line-associated bloodstream infections (CLABSIs) are one of the most critical HAIs, with an excessive mortality rate of 12-25%. 3

MATERIALS AND METHODS
In general, 150 blood samples and catheter tips were collected for culture when primary or secondary bacteremia was suspected in patients admitted to the tertiary care centre's intensive care unit over a one-year period.Central lines were inserted with strict aseptic precautions as consistent with the preferred protocol.Catheter tip specimens were processed using the conventional culture plate method; a 4 cm segment of the catheter tip was cut and kept in a sterile universal container.It was transported immediately, preventing drying and allowing it to be processed within two hours of being collected.5][6] In positive cultures, bacterial colonies have been processed and identified.The phenotypic identity of pathogens and antimicrobial sensitivity were performed by way of an automatic approach, VITEK 2, 7 as per Clinical and Laboratory Standard Institute (CLSI) guideline 2022. 8The CLABSI rate was calculated by means of the following equation 9 :

Number of CLABSI cases Number of central line days
X 1000

Statistical analysis
Statistical analysis was done using Microsoft Excel 2007 (Microsoft Corp., Redmond, WA, USA) and SPSS version 20 (IBM Corp., Somers, NY, USA).Frequencies and percentages were calculated.The Chi-square test was used to calculate the relationship between pathogens, isolated organisms, and infection.The significance level was set at P< 0.05.

DISCUSSION
This study examined the incidence, clinical and microbiological characteristics of the development of catheter-related infections at a tertiary health care centre.Of the 150 patients, 40 (26.7%)developed a bloodstream infection 4-5 days after CVC insertion.The age group 50 to 60 years old had the highest number of CLABSI cases. 10In our study, catheter colonisation occurred at a rate of 30% (45).The incidence of catheter colonisation in various other studies ranged from 36% to 70%. 11,12which was co related to our study.Gram-positive Cocci colonised the catheters the most (17.78%),followed by Klebsiella pneumoniae12 (26.67%),Escherichia coli 8 (17.78%),Acinetobacter baumanii 4 (8.89%), and Pseudomonas aeruginosa 4 (8.89%).Gram-positive cocci were the most predominant colonisers of central lines, as said in other research. 13,14Among the 150 cases, the most common site for central line catheter insertion was subclavian (50%), followed by jugular (40%), and femoral (10%).Out of 40 cases of CLABSI, the highest percentage of infection was discovered in the femoral catheter (80%), [15][16][17] followed by the jugular catheter (60%) and the subclavian catheter (30%), with a p-value of <0.0031, which was statistically significant and was calculated by the Chi-square test.The occurrence of CLABSI in different site reported by YazanHddadin et al. 18 was related to our study.
In our observation, the CLABSI rate per 1000 days on the central line was 7.8, which was consistent with SZ Bukhari et al. benchmark of 6.8. 18Fluctuation in the rates of CLABSI could be  attributed to differences in methods employed for blood culture (manual or automated), volume of blood used (5 or 10 ml), number of blood cultures taken (2 or 3 sets), and the lack of clinical indications (variations in clinical signs and symptoms of BSI), eventually increasing the proportion of negative results. 191][22] Above all, infections caused by anaerobes and other etiological agents would had add to this disparity, with respect to the rate of isolation of cultures. 23When calculating the incidence density of CLABSIs, the device associated infection guidelines of National Healthcare Safety network (NHSN) 24 endorse that we take "centralline days" as the denominator for the calculation."Central line days" were calculated using a day-byday count of patients on a central line who were admitted to a healthcare facility.This adjusts the risk of CLABSI with respect to the duration that the central line was in place.
The presence of such a resistant strain in our hospitals has grave implications.It is time to establish antibiotic surveillance systems, with each country having its own antibiotic policy and adhering to good infection control practices, including hand hygiene. 34The colonisation of the catheter with organisms and the production of biofilm play an important role in the development of CLABSI-associated septicaemia and multi-organ failure. 35Thereby, both central line insertion and maintenance bundle have to be followed strictly to reduce the CLABSI in intensive care units. 36,37ctive participation of clinicians in the early diagnosis of sepsis and proper collection of samples at an appropriate time for the early diagnosis of sepsis will thereby decrease morbidity and mortality associated with CLABSI. 38,39More emphasis on teaching and education of medical and paramedical staff regarding the insertion and maintenance bundle for the central line, catheter hub care and after-wound care aids

Limitations
Due to the small sample size confined to one hospital, our study's ability to generalise current findings was limited.As a result, our study recommended that the study be replicated on a larger probability sample from different geographical locations.

Table 1 .
Categorization of patients on the basis of central line associated bloodstream infections

Table 2 .
Shows the antibiotic sensitivity pattern of Gram-positive isolates in cases of central line-associated bloodstream infection

Table 3 .
Shows the antibiotic sensitivity pattern of Gram-negative isolates in cases of central line-associated bloodstream infection

Table 4 .
Distribution of MRSA, MRCoNS, ESBL in patients with central line associated bloodstream infection

Table 5 .
Central line associated bloodstream infections in various clinical conditions

Table 6 .
Mortality in patients with central line associated bloodstream infection cases

Table 7 .
Mortality in CLABSI in relation to central line catheters CLABSI: Central line associated blood stream infection

Table 8 .
[40][41][42] in different catheter sites value by Chi-square test, statistically significant in the prevention of catheter colonisation and thus reduces CLABSI.Adequate hand hygiene is the most important preventive step for the transmission of multidrug-resistant (MDR) organisms among patients with central lines.[40][41][42] P