Blood Cultures Flashcards
Obj. 1: Define the following terms: bacteremia, fungemia, viremia, pseudobacteremia
Bacteremia: presence of bacteria in the blood
Fungemia: presence of fungi in the blood
Viremia: presence of a virus in the blood
Pseudobacteremia: presence of bacteria in the blood from contamination during collection
Obj. 1: Define the following terms: septicemia
Septicemia: multiplying organisms in the bloodstream plus the presence of symptoms
Obj. 1: Define the following terms: SIRS (Systemic Inflammatory Response Syndrome)
SIRS (Systemic Inflammatory Response Syndrome): criteria for the designation of SIRS requires at least two (2) of these —
- Temperature
- Heart Rate
- Respiratory rate
- WBC count
Obj. 1: Define the following terms: sepsis
Sepsis: dysregulation of the host response to an infection accompanied by organ dysfunction
Obj. 1: Define the following terms: septic shock
Septic shock: sepsis plus cardiovascular dysfunction
Obj. 1: Define the following terms: endocarditis
Endocarditis: inflammation of the heart due to a bacterial infection
Obj. 1: Define the following terms: Disseminated intravascular coagulation (DIC)
Disseminated intravascular coagulation (DIC): abnormal blood clotting throughout the body’s blood vessels
Obj. 2: List common symptoms associated with possible septicemia
- Fever
- Chills
- Tachycardia
- Hyperventilation
- Toxicity
- Prostration
- Mental confusion
- Dizziness
Obj. 3: List five (5) risk factors associated with bacteremia
- Age of the patient
- Increased use of invasive procedures
- Antimicrobial resistance
- Diagnostic criteria and coding practices
- Decreased immune competency of certain patient
populations
Obj. 4: Classify bacteremia by its site of origin (primary and secondary bacteremia)
Primary bacteremia: intravascular
Secondary bacteremia: extravascular
Obj. 5: Classify bacteremia by the duration of the bacteremic episode (transient, intermittent, continuous)
Transient: “passing through,” occurs when bacteria enter the blood after manipulation of tissue with normal flora
Intermittent: infected site sporadically releasing bacteria into the blood (“seeding”)
Continuous: intravascular source and are consistently present in the bloodstream
Obj. 6: Discuss situations that may result in transient, intermittent, continuous, primary, and secondary bacteremia
Transient: dental work, endoscopy
Intermittent: abscess
Continuous: biofilm on infected IV catheter
Primary: infected cardiac valve, infected IV catheter
Secondary: abscess, pneumonia patients, UTI
Obj. 7: Discuss the expected lab test results for patients with septicemia for the following tests: Platelet count, coagulation tests, WBC count, lactate, blood glucose, CRP, and PCT (Procalcitonin)
Plt. count: decreased
Coag tests: High PTT and PT
WBC count: increased (can be decreased)
Lactate: increased
Glucose: increased or decreased
CRP: increased
PCT: increased
Obj. 8: Recognize that one blood culture “set” consists of two (2) blood culture bottles (aerobic and anaerobic)
Recognize that one blood culture “set” consists of two (2) blood culture bottles (aerobic and anaerobic)
Obj. 9: Describe the purpose of sodium polyanetholsulfonate (SPS) and resins (ARD antimicrobial removal devices)
Sodium Polyanetholsulfonate (SPS): anticoagulant
Resins: binds antimicrobials
Obj. 10: Discuss the proper method of collecting (including sterile collection, recommended maximum number of sets, timing of collection, amount of blood, and what to do if an IV is present, patient is receiving antimicrobials, or spiking a fever) a blood specimen for bacteriologic culture
Obj. 11: Correlate the number, timing, ratio of patient blood to culture broth, and volume of specimens with optimal recovery of organisms for meaningful clinical use
Sterile collection
- Clean skin w/ isopropyl alcohol
- Follow with iodine/Chlorhexidine in circles
- Remove residue with alcohol pad
Recommended maximum number of sets
- 3 culture sets within 24 hours
Timing of collection
- Acute: multiple cultures in the first 6-12 hours
- Chronic: 2-3 cultures per day for 3-4 days
Amount of blood
- Blood to medium ratio: 1:10
- Pediatric venipuncture: 2-6 mL (BLC: 1-3 mL)
- Adult venipuncture: 16-20 mL (BLC: 8-10 mL)
What to do if an IV is present
- If both arms have IV sites, draw below IV
Patient is receiving antimicrobials
- Collect cultures before antimicrobial therapy
Spiking a fever
- Collect before fever spike
Obj. 12: Discuss the proper method for transporting and incubating a blood specimen for bacteriologic culture
Transport to lab at room temperature ASAP; if delayed, can be held at room temp for 48 hours
Incubate 35 +/- 2 deg. C for 5-7 days ambient air
Obj. 13: Describe the proper blood culture procedure for possible brucellosis [include the Bactec FX and manual biphasic media (Ruiz Casteneda) in your answer]
Bactec FX
- Incubate for 14 days
Manual biphasic media (Ruiz Casteneda)
- Incubate 35 +/- 2 deg. C for 6 weeks and terminally subculture
Obj. 14: Discuss the basic principles of the Wampole (DuPont Isolator) Lysis Centrifugation Method
RBCs and WBCs are lysed to release fungi and intracellular pathogens — centrifuge and plate sediment/pellet
Obj. 30: Evaluate a Gram stained smear of a blood culture bottle to determine the likely organism(s)
Actinomyces
Obj. 31: Correlate the image with a clinical scenario(s)
Recognize which is a common contaminant
Actinomyces
- Tissue necrosis and dissemination to brain
Obj. 30: Evaluate a Gram stained smear of a blood culture bottle to determine the likely organism(s)
Actinomyces
Obj. 31: Correlate the image with a clinical scenario(s)
Recognize which is a common contaminant
Actinomyces
- Tissue necrosis and dissemination to brain
Obj. 30: Evaluate a Gram stained smear of a blood culture bottle to determine the likely organism(s)
Actinomyces
Obj. 31: Correlate the image with a clinical scenario(s)
Recognize which is a common contaminant
Actinomyces
- Tissue necrosis and dissemination to brain
Obj. 30: Evaluate a Gram stained smear of a blood culture bottle to determine the likely organism(s)
Bacillus (GP and decolorized)
Obj. 31: Correlate the image with a clinical scenario(s)
Recognize which is a common contaminant
Bacillus (GP and decolorized)
COMMON CONTAMINANT!
- Anthrax
- Food poisoning (meat, chicken, fried rice, etc.)
Obj. 30: Evaluate a Gram stained smear of a blood culture bottle to determine the likely organism(s)
Bacillus
Obj. 31: Correlate the image with a clinical scenario(s)
Recognize which is a common contaminant
Bacillus
COMMON CONTAMINANT!
- Anthrax
- Food poisoning (meat, chicken, fried rice, etc.)
Obj. 30: Evaluate a Gram stained smear of a blood culture bottle to determine the likely organism(s)
Bacteroides fragilis (pleomorphic)
Obj. 30: Evaluate a Gram stained smear of a blood culture bottle to determine the likely organism(s)
Bacteroides fragilis (vacoulated)
Obj. 30: Evaluate a Gram stained smear of a blood culture bottle to determine the likely organism(s)
Campylobacter
Obj. 30: Evaluate a Gram stained smear of a blood culture bottle to determine the likely organism(s)
Campylobacter
- Diarrhea
Obj. 30: Evaluate a Gram stained smear of a blood culture bottle to determine the likely organism(s)
Clostridium clostridioforme (GNR) [top]
Clostridium perfringens (GPR) [bottom]