An Intervention Based Prevention of Catheter Associated Blood Stream Infection in Adult Critical Care Unit

Central line associated blood stream infection (CLABSI) is a device associated infection posing a serious threat among critically ill patients. It also increases the cost of hospital stay, morbidity and mortality. The aim of the study was to implement bundle care approach and identify CLABSI rates post intervention in comparison with the retrospective data. All the patients who were admitted in the ICU with central line (CL) in place were included in our study. The bundle care approach was implemented for all the patients when CL was introduced. We compared the CLABSI rates during the implementation period with the previous year CLABSI rates. The CLABSI rates were compared during the pre-intervention and during the intervention. The pre-intervention rate was 7.48 per 1000 catheter days, whereas the post intervention rates were 1.01 and zero per 1000 catheter days. The etiological agents isolated from CLABSI were Enterobacter aerogenes (30%) followed by Klebsiella pneumonia (20%) and Pseudomonas aeruginosa (20%). Similarly the antibiotic resistance was highest in ceftriaxone (55.5%) and lowest in piperacillin tazobactam (11.1%). A strict adherence to bundle care and proper education of the ICU team members including the doctors and nurses would effectively reduce infection rates. The CLABSI rates were 7.48 per 1000 catheter days in the previous year. However after implementation of bundle care the CLABSI rates reduced to zero.


INTRODUCTION
The infections which are acquired 48 hours post admission to the hospital and not in incubation at the time of admission to the hospital are termed as Health Care Associated Infections (HAIs). It is quite alarming that Device associated infections contribute a majority of HAIs. Out of which Central Line Associated Blood Stream Infection (CLABSI) pose a serious threat and increases the cost of hospital stay, morbidity and mortality among the hospitalized patients 1 . A central line is an intravenous access device which is introduced into the great vessels of the heart for diverse purposes such as administration of medication, intravenous fluids, blood products and total parenteral nutrition among critically ill patients 2 . However it is crucial that blood stream infections arise as a sequel of central line in place. The risk factors for CLABSI include host factor, interventional factor and catheter related factors. Often a breach in aseptic precautions during insertion and handling leads to infection 3 . Comparatively the infection rates are higher among the developing countries rather than the developed countries. As per the International Nosocomial Infection Control Consortium (INICC) there is a fivefold rise in infection rates compared to United States 4 . In a study conducted in North India the mortality rate was 56%. A strict surveillance and bundle care approach can prevent such infection rates and mortality among critically ill patients. The aim of the study was to implement bundle care approach and identify CLABSI rates post intervention in comparison with the retrospective data.

Study design
The study was conducted from January 2016 to December 2018 at our tertiary care hospital in Puducherry. The study population incudes all adult patients admitted with various surgical and medical conditions at the intensive care units (ICUs). Central Line (CL) insertion done as a part of their Medical management by our Critical care specialists and to whom the Central line were at place in-situ for at least 48 hours were only included in this study. The bundle care approach was implemented for all the patients when CL was planned to introduce. We followed CDC guidelines for implementation of bundle care 5 . The prevention bundle was observed in two phases as insertion phase and maintenance phase ( Table 1, 2). The insertion phase included proper hand hygiene, optimum site for insertion of catheter, proper skin preparation with chlorhexidine and maximal sterile barriers during insertion. The maintenance bundle included hand hygiene, sterile dressing change and aseptic accession of the CL with periodic review for the line in place 6 . We compared the CLABSI rates during the implementation period with the previous year CLABSI rates. CLABSI identification CLABSI was identified when any laboratory confirmed pathogen isolated 48 hours after the CL insertion from one or more percutaneous blood culture, provided no other source of infection was identified 7 .

Data collection
The ICU nurses and doctors were trained to follow bundle care approach. The bundle adherence was verified by a checklist distributed among the ICU nurses. The study was done with co-operation of the hospital infection control team at our institute. The maintenance phase was critically observed by the infection control nurses and liaison nurses regularly.
In case of suspected infection, around 5 to 10 ml of blood was collected from patients in brain heart infusion broth (BHI) and sub-cultured on blood agar, Mac-conkey agar and chocolate agar after 24 hrs, 48 hrs and one week of aerobic incubation 8 . The organisms were identified by standard bacteriological procedure. The antimicrobial sensitivity was identified by Kirby-Bauer disc diffusion method.

Statistical methods
The CLABSI rate during the intervention period was compared with the previous rate. The statistical analysis was done with SPSS for windows version 16. The CLABSI rates were calculated by the formula total number of CLABSI episodes per thousand central line days. p value was calculated by Repeated measures Anova test.

RESULTS
The CLABSI rates during the preintervention and intervention period is shown in the table 3, 4 and Fig. 1.  The CLABSI rates were compared with the preintervention period and p value was calculated by using Repeated measures Anova test. The p value was < 0.001 which was statistically significant.
The etiological agents isolated from CLABSI are shown in table 5. The common organism isolated were Enterobacter aerogenes (30%) followed by Klebsiella pneumonia (20%) and Pseudomonas aeruginosa (20%). Similarly the antibiotic resistance is shown in table 6. The resistance was highest in ceftriaxone (55.5%) and lowest in piperacillin tazobactam (11.1%).

DISCUSSION
CLABSI is a blood stream infection with a CL in place for more than two calendar days. This term has been endorsed by the National Health care Safety Network (NHSN) for surveillance purpose. The patient should have signs of sepsis such as fever, chills and hypotension, with a positive culture from CL and peripheral line.
Device Associate Infection is a major threat increasing the morbidity and mortality among critically ill patients. A care bundle involves a set of sequential steps which focus both infection prevention and control. It aims at a prompt delivery of quality clinical care 9 . Quite often the breach in the continuity of the skin acts as a source of infection. In addition, frequent intervention by the health care team also acts as a source of infection.
Implementation of proper bundle care for CL has reduced the CLABSI rates as reported from various studies around the world.
In a study conducted in Columbia there was a significant reduction in CLABSI rate of 73% after intervention 10 . Similar other studies from New Zealand and Kuwait have proved reduction in CLABSI rates from 3.32 to 0.28 per 1000 catheter days and 14.9 to 11.08 per 1000 catheter days respectively 11,12 . In India around 53% reduction in CLABSI rates had been proven with CLABSI rates from 6.4 to 3.9 per 1000 catheter days. These studies show a positive impact on bundle care approach to prevent CLABSI 13 . With available data, developing countries can also prevent infection rate with strict adherence to the bundle care in comparison to the developed countries.
However the aim of bundle care is to totally curb CLABSI rate to zero. The zero CLABSI rate though attained has to be sustained so that mortality is reduced.
In this study we aimed at reduction of CLABSI in comparison to the previous year. The CLABSI rates were 7.48 per 1000 catheter days in the previous year. However after implementation of bundle care the CLABSI rates reduced to zero. There are studies which show that zero rates could be attained and sustained with proper bundle care 14,15 .
The common organism isolated were Enterobacter aerogenes (30%) followed by Klebsiella pneumonia (20%) and Pseudomonas aeruginosa (20%). However in contrast, based on NHSN data the common organism isolated are Gram-positive organisms such as coagulasenegative staphylococci which accounts for 34.1%; followed by Klebsiella, Enterobacter and Pseudomonas which accounts for 5.8%, 3.9% and  3.1% respectively 16,17 . In this present study the common isolates were Gram negative followed by gram positive organism.

CONCLUSION
CLABSI is a device associated blood stream infection which can be prevented by strict bundle care adherence. A proper education of the ICU team members including the doctors and nurses would effectively reduce infection rates. However to sustain reduced CLABSI rates ample support from the ICU team in cooperation with the infection control team is mandate.