Collection of blood for culturing

COLLECTION OF BLOOD FOR CULTURING

1. COLLECTION OF BLOOD FOR CULTURING Dr.T.V.Rao MD Dr.T.V.Rao MD 1

2. What is a Blood Culture? A blood culture is a laboratory test in which blood is injected into bottles with culture media to determine whether microorganisms have invaded the patient’s bloodstream. Dr.T.V.Rao MD 2

3. Need for Blood Culture? No microbiological test is more essential to the clinician than the blood culture. The finding of pathogenic microorganisms in a patient’s bloodstream is of great importance in terms of diagnosis, prognosis, and therapy.” - L. Barth Reller, Clin. Infect. Diseases, 1996 Dr.T.V.Rao MD 3

4. Blood Culture is done to Detect Infectious Diseases Blood culture is a microbiological culture of blood. It is employed to detect infections that are spreading through the bloodstream (such as bacteremia, septicemia amongst others). This is possible because the bloodstream is usually a sterile environment Dr.T.V.Rao MD 4

5. Blood culturing most important and life saving Investigation Needs optimal Methods for Diagnosis of Blood Borne Pathogens Dr.T.V.Rao MD 5

6. Blood Collection Aseptic collection procedure is critical Amount of blood 1:10 ratio of blood to broth Younger than 10 years – 1 ml of blood for every year of life Over 10 years – 20 ml Dr.T.V.Rao MD 6

7. Blood Collection Frequency of Collection Depends if bacteremia is transient, intermediate or continuous Number of cultures collected are usually inversely related to the type of bacteremia Usually x3 from different body sites Dr.T.V.Rao MD 7

8. Blood Culture Methods Conventional Broth Systems One aerobic bottle and one anaerobic bottle per blood collection Aerobic broth contains soybean casein digest broth, Tryptic or trypticase soy broth, Brucella agar or Columbia broth base Anaerobic broth is usually the same as aerobic with addition of 0.5% cysteine in an aerobic environment Must be subcultured and gram stained manually Dr.T.V.Rao MD 8

9. Venipuncture Venipuncture is the process of obtaining intravenous access for the purpose of intravenous therapy or obtaining a sample of venous blood. This procedure is performed by medical laboratory scientists, medical practitioners, some EMTs, paramedics phlebotomists and other nursing staff. Venipuncture is one of the most routinely performed invasive procedures and is carried out for two reasons, to obtain blood for diagnostic purposes or to monitor levels of blood components (Lavery & Ingram 2005). Dr.T.V.Rao MD 9

10. Phlebotomy Definition phle·boto·my (fli) noun the act or practice of bloodletting as a therapeutic measure Phlebotomy from Greek words, phlebo , relates to veins, tomy , relates to cutting. Opening a vein to collect blood Dr.T.V.Rao MD 10

11. LABELING THE SAMPLE P roperly labelled sample is essential so that the results of the test match the patient. The key elements in labelling are: Patient's surname, first and middle. Patient's ID number. NOTE: Both of the above MUST match the same on the requisition form. Date, time and initials of the phlebotomist must be on the label of EACH tube. Dr.T.V.Rao MD 11

12. Principles for Collection Gloves will be worn in accordance with standard precautions. •Appropriate verification of the patient's identity, by means of an armband or area specific procedure, will occur before the specimen collection. •Cultures should be drawn before administration of antibiotics, if possible . ??? B lood cultures should not be drawn from lines, but should be drawn viavenipuncture. Dr.T.V.Rao MD 12

13. What Materials We need Chlorhexidine swabs (1-2 packages) Alcohol swabs Blood culture bottles (2 bottles per set) 2 syringes (adult: 20 cc, paediatric: 5 cc) 2 needles (adult: 22 gauge or preferably larger butterfly or standard needle; pediatric: 25 or 23 gauge butterfly or standard needle ) Gloves (sterile &nonsterile) Tourniquet Sterile gauze pad Adhesive strip or tape Self-sticking patient labels Plastic zip lock specimen bags Dr.T.V.Rao MD 13

14. The requisitions form should be completely filled out, and the requisition must indicate the tests ordered . Dr.T.V.Rao MD 14

15. Self Protection A few ways to make sure your role in the collection process is carried out with efficiency, orderliness and safety Dr.T.V.Rao MD 15

16. Steps 1 – 3, Check, Explain, Wash 1.Identify the patient 2.Explain the procedure to the patient. 3.Wash hands with soap and water with friction for 15 seconds or use alcohol based hand rub Dr.T.V.Rao MD 16

17. Materials Chlorhexidine swabs (1-2 packages) Alcohol swabs Blood culture bottles (2 bottles per set) 2 syringes (adult: 20 cc, paediatric: 5 cc) 2 needles (adult: 22 gauge or preferably larger butterfly or standard needle; pediatric: 25 or 23 gauge butterfly or standard needle ) Gloves (sterile &nonsterile) Tourniquet Sterile gauze pad Adhesive strip or tape Self-sticking patient labels Plastic zip lock specimen bags Dr.T.V.Rao MD 17

18. . Barrier protection for the phlebotomist consists of the latex gloves . Dr.T.V.Rao MD 18

19. Obtaining Blood Locate the vein Prep kit Alcohol 5 sec. Dry 30-60 sec ( resource poor conditions ) Ideal to collect with alcohol swabs containing 2% Chlorhexidine and 70% isopropyl alcohol Remove caps, clean with alcohol Put on gloves Without palpating, draw 20 ml and put 10 in anaerobic and 10 in aerobic bottle Dispose of syringe in sharps container Label bottles and send to lab Dr.T.V.Rao MD 19

20. Method of B lood Collection A minimum of 10 ml of blood is taken through venipuncture and injected into two or more "blood bottles" with specific media for aerobic and anaerobic organisms. The blood is collected using clean technique. This requires that both the tops of the culture bottles and the venipuncture site of the patient are cleaned prior to collection with alcohol swabs containing 2% Chlorhexidine and 70% isopropyl alcohol. Dr.T.V.Rao MD 20

21. The area of skin is cleaned with a disinfectant, or an alcohol swab. Using sterile gloves, do not wipe away the surgical solution, touch the puncture site, or in any way compromise the sterile process. It is vital that the procedure is performed in as sterile a manner as possible as the persistent presence of skin commensals in blood cultures could indicate endocarditis but they are most often found as contaminants Dr.T.V.Rao MD 21

22. The vein is anchored and the needle is inserted. Dr.T.V.Rao MD 22

23. The vacutainer tube is depressed into the needle to begin drawing blood Dr.T.V.Rao MD 23

24. Additional vacutainer tubes can be utilized. Determine what tests are ordered and what tubes will be necessary BEFORE you begin to draw blood, and determine the order of draw for the tubes. . Dr.T.V.Rao MD 24

25. When the final tube is being drawn, release the tourniquet. Then remove the tube, and remove the needle. Dr.T.V.Rao MD 25

26. After the needle is removed from the vein, apply firm pressure over the site to achieve haemostasis . Dr.T.V.Rao MD 26

27. Apply a bandage to the area. Dr.T.V.Rao MD 27

28. Preparation of Cap before Injecting Blood Prep the rubber cap of the blood culture bottles with an alcohol pad in a circular motion. Allow the alcohol to dry. Dr.T.V.Rao MD 28

29. Inject the Blood ….. Inject the blood into the Selected Media Gently rotate the bottles to mix the blood & the broth (do not shake vigorously). Dr.T.V.Rao MD 29

30. Follow the universal precautions when disposing Needle Dispose of needle in sharps container and dispose of other waste in proper container Dr.T.V.Rao MD 30

31. Label the tubes, checking the requisition for the proper identification . Dr.T.V.Rao MD 31

32. Give the all possible Medical Information Patient’s name • Hospital number (Patient ID) • Patient’s location (room and bed #) • Date and time of collection • Collector’s initials • Site of venipuncture • Or other information as per facility Include you Mobile Contact No – A vital information can be delivered any time Dr.T.V.Rao MD 32

33. Document the Medical Records Document the following in the medical record: –Date & time specimen obtained –Site of specimen collection Dr.T.V.Rao MD 33

34. Frequency of Collection Frequency of Collection Depends if bacteremia is transient, intermediate or continuous Number of cultures collected are usually inversely related to the type of bacteremia Usually x3 from different body sites Dr.T.V.Rao MD 34

35. Second Set If 2 or more sets of blood cultures have been ordered, obtain the second set in the same manner as the first, making a new venipuncture at a different site . Dr.T.V.Rao MD 35

36. Newer Blood Culture Methods Newer Blood Culture Systems Biphasic Broth-Slide System Agar “paddles” attached to top of bottle Closed system Continuous Monitoring Blood Culture Systems BacTec – measures 14CO2 BacTec 9000 Series – measures CO2 ESP – measures consumption of gases BacT-Alert – measures change in pH Dr.T.V.Rao MD 36

37. The Contaminated Blood Culture If the skin is not adequately cleansed before drawing blood for culture, bacteria on the skin will be injected into the bottle, producing a false positive blood culture It is difficult for the physician to determine whether the bacteria growing in the blood culture is a real pathogen causing bloodstream infection or whether bacteria on the skin have contaminated the culture. This can lead to excess use of antibiotics and prolongation of hospital stay. Dr.T.V.Rao MD 37

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