Blood Culture Collection Introduction Blood culture - Blood - sterile fluid in the body - The incubation of blood sample for the purpose of detecting and identifying disease-causing bacteria - Performed on patients with suspected bacteremia and septicemia - Bacteremia - Bacteria in Blood - Septicemia - Pathogenic bacteria in the blood; More dangerous because microorganisms are fetal - Sample: venous blood Note: - There should be no present microorganisms in the blood If found, patient has bacteremia or septicemia Normal flora of skin during surgery was able to enter the circulation leading to bacteremia If septicemia, this means you already have bacteria that has already affected a specific organ in your body and reaches the circulation in your body, which infects your whole body Blood Culture Collection - Recent literature of the American Society for Microbiology (ASM) states that 2-4 blood cultures are necessary to optimize detection of bacteremia. - CLSI blood culture guidelines recommend collecting paired AEROBIC and ANAEROBIC blood culture bottles for routine blood culture collection. Recommendations for the number of blood cultures to collect include the following: - For critical situations which rapid administration of antibiotics is important, 2-3 cultures, one right after another from different sites. - For FUO (fever of unknown origin) 2-3 cultures one right after the other from different sites are usually required. If these are negative after 24-48 hours, 2 more cultures from different sites are typically collected. - If bacteremia or fungemia are suspected but blood culture are consistently negative, Alternative bottles may be required to optimize the recovery of bacteria and fungi - ARD - antibiotic removal devices which are incorporated in blood collection tubes Timing and considerations - They should be collected as close to the time ordered as possible. - Collection time depends on the status of the patient; The patient is in critical condition, or an antibiotic must be given right away. - When more than one set is ordered for collection at the same time, the second set should be obtained from a separately prepared site on the opposite arm if possible. - NOTE: Blood cultures are ordered immediately before or during fever spikes when bacteria are most likely to be present. Recommended Volume - Volume to be drawn is the most important variable in detecting the causative agent. - The identification of pathogens increases in direct proportion to the volume of blood cultured. - for pediatrics: 1-5 mL is enough - for adult: 5-10 mL According To CLSI, most bacteremia is caused by - AEROBIC and FACULTATIVE (able live with or without oxygen) bacteria. - Pathogenic YEASTS are recovered almost exclusively from AEROBIC bottles. - If less than the recommended volume is collected, the blood should added to the AEROBIC first; any remaining should be added to the anacrobic vial. pic Skin antisepsis - The destruction of microorganisms on the skin. - Is a critical part of the blood culture collection procedure. - The major difficulty in the interpretation of blood cultures is contamination by normal flora. - Failure to carefully clean the venipuncture site can introduce skin-surface bacteria into the blood culture bottles. Antiseptic or Sterile Technique - A procedure set to minimize the risk of contamination by normal microbial flora on the skin. - To minimize the risk of contamination by skim flora, collection sites require: 30-60 seconds second friction scrub to get the bacteria beneath the dead skin cells - Tincture of iodine, chlorhexidine gluconate, povidone/70% ethyl alcohol combination have all been shown to be effective antiseptics for cleaning blood culture collection sites. - CLSI : Alcohol - Iodine - Most literatures: Alcohol - Iodine - Alcohol AIA NOTE: - Cleansing the patients skin with tincture of lodine and or chlorhexidine is superior to using iodophors such as povidone in reducing contamination rate at blood culture collection sites. - According to CLSI, CLORHEXIDINE GLUCONATE is the recommended blood culture site disinfectant for infants two months and older patients with iodine sensitivity. PIC NG SteriPathGen2 - Has been shown to reduce blood culture contamination Preassembled sterile closed-system device which includes an integrated butterfly safety needle and transfer adapter, which is used to divert, sequester, and isolate the first 1.5 to 2mL of blood flow. The diverted/isolated blood contains skin plugs, cells and microbes that could result in contamination. Then the device then opens an independent, second sterile blood flow path for the specimen collection into the blood culture. Media Inoculation Methods Direct Inoculation Methods the specimen is collected directly into the blood culture medium via butterfly system. Fill the AEROBIC vial first, then anaerobic Syringe inoculation Blood must be transferred to the bottles after the draw is completed. Inoculate the ANAEROBIC bottle first then aerobic. Intermediate Collection Tube Via SPS, this anticoagulant reduces the action of a protein called COMPLEMENT that destroys bacteria. Antimicrobial Neutralization Products FAN - Fastidious Antimicrobial Neutralization: contains CHARCOAL which helps to neutralize the antibiotic. ARD - Antimicrobial removal device that contains a RESIN that removes antimicrobials in the blood. PEDIATRIC BLOOD CULTURE CONSIDERATIONS - It is recommended that in place of the iodine step, the site should be cleansed two additional times with separate preparation pads saturated with 70% isopropyl or ethyl alcohol. A - The volume of blood collected for culturing should be from 1-4% of the patient's total blood volume. CATHETER CONSIDERATIONS - When collecting blood cultures from a vascular access device (VAD), such as catheter or IV, one set should be drawn by VENIPUNCTURE, and one drawn through the CATHETER. - this allows for the correct interpretation of a positive result since cultures drawn through VAD may indicate bacterial growth in the device, rather than in blood. Materials • Gloves • 70% Alcohol • Povidone iodine/ chlorhexidine gluconate • Gauze pad • Tourniquet • Blood culture bottle • Syringe / Butterfly needle • Sharps container Procedure 1. Identify the patient. Explain the procedure. 2. Prepare all materials 3. Perform hand hygiene. Apply gloves. 4. Position the patient. Apply the tourniquet and select the venipuncture site.** 5. Clean the site. - 30 secs: 70% alcohol - 30 secs: iodine tincture/ 60 secs: povidone-iodine - Concentric motion: Inner to outer - Diameter: at least 2.5 inches 6. Remove the protective cover of the culture bottle. And clean the top of the bottle with 70% alcohol or iodine. 7. Mark the minimum and maximum fill lines. - Adults: 5ml and 10mL - Pediatric bottles: 1mL and 3mL 8. 9. Insert the needle and start blood collection. - Butterfly Method - Aerobic -> anaerobic - Use a blood culture tube holder - Keep the bottle lower than the arm to avoid blood reflux - Syringe Method - Remove needle after extraction - Attach safety blood transfer device - Anaerobic -> aerobic & - Intermediate collection tube - SPS tubes with ACD (Yellow stopper) - SPS inhibits - Complement - Leukocyte (phagocytosis) - Antibiotics 10. Apply pressure to the puncture site after extraction. Wipe off iodine with 70% alcohol. 11. Label the culture bottles. 12. Discard all used materials. Perform hand hygiene. 13. Thank the patient. Antiseptic sequence: - 30 secs: 70% alcohol - 30 secs: iodine tincture/ 60 secs: povidone-iodine - After venipuncture: 70% alcohol to clean iodine Antisepsis procedure - Concentric motion: Inner to outer - Diameter: at least 2.5 inches - For iodine-sensitive patients: chlorhexidine gluconate Bottle sequence - Butterfly: Aerobic -> anaerobic - Syringe: Anaerobic - aerobic Blood Culture Must Knows - Collection of blood culture in a timely fashion is important. Commonly, blood cultures are ordered before or immediately after a fever spikes - Skin antisepsis is the most important part of blood culture
