University:
Franklin University
Course:
EXS-351 | Kinesiology/Biomechanics
Academic year:

2020
Views:

423

Pages:

33
Author:

AuroraArcher

BacT/Alert 3D INTRODUCTION • An automated microbial detection system. • Based on colorimetric technology. • Provide optimal environments for the recovery of a wide range of microorganisms, including bacteria, fungi and mycobacteria. • Growth monitoring every 10 minutes. INSTRUMENT • Consists of one controller module and one incubator. • Control module manages all bottle inventory and data, while the incubator module performs the testing. • There is flexibility to add up to six incubator modules to a single controller module. • There are two BacT/ALERT 3D models available:A. The BacT/ALERT Combination Module includes incubation space for 120 bottles (expandable to 840). B. The BacT/ALERT 3D System includes incubation space for 240 bottles (expandable to 1440). Combination Module Structure and function of sensor • A C02 sensor is bonded to the bottom of each bottle and is separated from the broth medium by a semipermeable membrane. • The sensor is impregnated with water vapor when the bottles are autoclaved during the manufacturing process. • The membrane is impermeable to most ions, including hydrogen ions, and to components of media and whole as well as degraded blood. • It is nearly impermeable to water but is freely permeable to C02. Carbon dioxide produced by growing organisms diffuses across the membrane into the sensor and dissolves in the water, thereby generating hydrogen ions according to the following equation: C02 + HO * H2CO3 *-> H++ HCO3- • Free hydrogen ions can interact with the sensor, which is light green in the alkaline state. • As C02 is produced and dissolves in the water, the concentration of hydrogen ions increases and the pH decreases. • This causes the sensor to become lighter which results in an increase of red light reflected by the sensor. • If there is high initial co2 content, an unusually high rate of co2 production, and/or a sustained production of co2, the sample is determined to be positive. Types of samples WHEN SHOULD A BLOOD CULTURE BE PERFORMED? • For all patients… • Who meet criteria for starting on the adult sepsis pathway • With severe pneumonia • With fever, or history of fever, and suspected or proven neutropenia • With fever and who are immunocompromised • With a fever or evidence of infection and have a vascular access device • With suspected bacterial endocarditis • With delirium or alteration of consciousness, even without fever • Overseas travelers with fever • … Per Cumitech • Blood cultures should be obtained as soon as possible after the onset of fever or chills & prior to the initiation of antibiotic therapy 13 Source: Clinical Excellence Commission, New South Wales, Australia, Blood Culture Sampling Guideline - Adult, September 2014 WHEN SHOULD BLOOD CULTURES BE DRAWN?  As soon as possible after the onset of clinical symptoms (fever & chills)  Blood should be obtained for culture before the administration of antibiotics  However, many patients with suspected BSIs are already receiving empiric antimicrobial therapy at the time blood cultures are obtained. This could potentially reduce the sensitivity of the test.  Nevertheless, because of concerns about microbial recovery from blood cultures in patients receiving systemic antimicrobial, media containing antibiotic binding resins are available  If blood culture is negative after 24 hours of incubation and patient is still septic 14 HOW TO OPTIMIZE BLOOD CULTURE SENSITIVITY • Optimal specimen collection: the pre-analytical steps are key to obtaining the best sensitivity • Pre-analytical factors maximizing blood culture sensitivity • Optimize blood volume • Optimize the number of bottles sets • Fast processing (by reducing the interval between blood collection & blood entry into the system) • Avoid contamination • Protocol compliance 15 HOW MANY SETS ? A “set” defined by number of independent venipunctures ONE blood cultures set consist of testing 20 mL in two bottles with 10 mL blood in each vial 16 CLSI*, M47-A, Principles and Procedures for Blood Cultures; Approved Guideline. J Clin Microbiol. 1976;3:643-645 Diagn Microbiol Infect Dis. 1983;1:107-110 J Clin Microbiol. 1994;32:2829-2831 Clin Infect Dis. 2004;38:1724-1730. BLOOD VOLUME INCREASE RECOVERY BY INCREASING NUMBER OF SETS… The number of blood culture sets improves the yield of pathogen recovery With two blood culture sets, the % of pathogen recovery is above 90% 17 Media • Readymade media, called as FAN PLUS media (fastidious antimicrobial neutralization plus media) • FAN® Plus Media range: efficiency with only 3 bottles type to manage •Aerobic, Anaerobic and Pediatric • Fill-to Mark: visual target for the right volume of blood • Ensure the optimum blood volume is drawn for maximum organism recovery Aerobic(FA) Pediatric(PF) Anaerobic(FN) FAN PLUS media Bottle advantages :• Are made of unbreakable plastic, which make them shatter-resistant and provides maximum safety. • Are lightweight to reduce the cost of disposal and shipping. • Offers effective organism growth from both blood and sterile body fluid samples, along with growth performance guidelines for use in delayed entry conditions. • Triple-layer bottle design ensures appropriate environment for reliable recovery of microorganisms. • FAN PLUS media made of complex media and neutralization beads. • complex media made of Tryptic Soy broth Brain heart infusion broth Amino acid • These resin beads :- Enhanced antibiotic neutralization compared to other resin technologies - Neutralize a broad range of antimicrobials Method • Collect blood sample/sterile body fluid under aseptic precaution • After collection 1. Select appropriate BACT/ALERT® culture medium bottle 2. Inoculate bottle with sample 3. Load bottle into BACT/ALERT® system • Once growth is detected, the system alarms both audibly and visually and the sample data is recorded. 1. PREPARATION Prepare the blood collection kit 24 Check expiration date Verify signs of damage, deterioration or contamination 1. PREPARATION Confirm patient’s identity 25 2. PREPARE BOTTLES FOR INOCULATION Wash hands (soap and water, then dry, or apply an alcohol hand rub) Remove the plastic « flip-cap » Desinfect the septum* Allow to dry 26 * Appropriate and recognized effective disinfectant, such as chlorhexidine in 70% isopropyl alcohol, 70% isopropyl alcohol, or tincture of iodine in swab or applicator form. 3. PREPARE VENIPUNCTURE SITE Apply a (disposable) tourniquet Palpate to identify the vein Wash hands again or use an alcohol hand-rub Cleanse using an appropriate desinfectant* Wait for full evaporation Apply clean examination gloves (sterile gloves are not necessary) 27 * Appropriate disinfectant, such as chlorhexidine in 70% isopropyl alcohol, or tincture of iodine in swab or applicator form. 4. VENIPUNCTURE USING A COLLECTION SET Attach the collection set to the adapter cap 28 To prevent contamination, do not re-palpate Insert the needle into the prepared vein 4. VENIPUNCTURE USING NEEDLE & SYRINGE Attach the needle to a syringe To prevent contamination, do not re-palpate Insert the needle into the prepared vein 29 5. BLOOD CULTURE BOTTLE INOCULATION USING NEEDLE & SYRINGE Start the transfer with the anaerobic bottle Add 10 ml of blood per adult bottle & up to 4 ml of blood for pediatric bottle 30 REQUIRED BLOOD VOLUME IMPROVES RESULTS • The volume of blood is the most critical variable to increase sensitivity • Bottle “Fill To” Line indicates the optimal fill amount for the phlebotomist • Sample volume determination to detect under/over-filled bottles • Quality compliance indicator: routinely monitor the volume • Increase traceability: bottle barcodes link specimen and patient 31 REQUIRED BLOOD VOLUME IMPROVES RESULTS • The volume of blood is the most critical variable to increase sensitivity • Bottle “Fill To” Line indicates the optimal fill amount for the phlebotomist • Sample volume determination to detect under/over-filled bottles • Quality compliance indicator: routinely monitor the volume • Increase traceability: bottle barcodes link specimen and patient 32 Positive and negative bottle POSITIVE BOTTLE NEGATIVE BOTTLE Advantage of BacT/Alert • • • • • • Early detection Neutralization of broad range of antibiotics Provide better environment One machine used for both aerobic and anaerobic culture Detect mycobacteria Cost effective