What does it mean if your blood is contaminated?
Having these pathogens in your bloodstream can be a sign of a blood infection, a condition known as bacteremia. A positive blood culture means that you have bacteria in your blood. Subsequently, question is, what does a contaminated blood culture mean to the patient?
What does a contaminated blood test mean?
Contamination of the blood specimen with just one part in twenty of this highly concentrated solution can falsely elevate the glucose concentration by as much as 100 mg/dL. Additionally, electrolytes measured on this contaminated specimen will be falsely decreased due to dilution. The laboratory may not catch every IV contaminated specimen.
What is the contaminated blood scandal?
What was the contaminated blood scandal? In the 1970s and 80s, thousands of people with haemophilia became infected with hepatitis C and HIV – the virus that leads to Aids – after receiving contaminated blood products from the NHS.
Can one get AIDS by consuming food contaminated with blood?
You cannot get it from consuming food handled by an HIV-infected person; even if the food contained small amounts of HIV-infected blood or semen, exposure to the air, heat from cooking, and stomach acid would destroy the virus.
How can blood get contaminated?
Gram-positive bacteria normally found on the skin, such as Staphylococcus epidermidis or Staphylococcus aureus, are the most common bacterial contaminants of blood products. This type of contamination is thought to occur when the bacteria on the skin is passed into the collected blood through the collection needle.
What is the most common cause of blood contamination?
Nonetheless, inadequate skin preparation is thought to be the most common cause of blood culture contamination (30, 89, 147).
What does a contaminated blood test mean?
In recent years, it has also become apparent that contaminated (i.e., the presence of a pathogen from outside the blood stream) blood cultures are common, leading to falsely positive test results.(1,2) Contaminated blood cultures constitute as many as half or more of all positive blood cultures in some centers, are ...
What kind of contamination is blood?
Biological contamination refers to food that's contaminated by substances produced by living creatures – such as humans, rodents, pests or microorganisms. This includes bacterial contamination, viral contamination or parasite contamination that's transferred through saliva, pest droppings, blood or faecal matter.
How do you prevent a blood infection?
How can I help prevent a blood infection?Keep skin scrapes, wounds, and IV sites clean. Watch for possible signs of infection, such as redness, swelling, drainage, or pain. ... Take care of your health. Try to get at least 7 to 9 hours of sleep each night.
What does a contaminated blood culture mean?
Blood culture contamination is defined as the recovery of normal skin flora (coagulase-negative staphylococci, Propionibacterium spp., Aerococcus, Micrococcus, Bacillus spp. [not B. anthracis], Corynebacterium spp. [diphtheroids], and alpha-hemolytic streptococci) from a single blood culture.
What are the 3 main types of contamination?
Here are the three types of contaminants: Biological: Examples include bacteria, viruses, parasites, fungi, and toxins from plants, mushrooms, and seafood. Physical: Examples include foreign objects such as dirt, broken glass, metal staples, and bones. Chemical: Examples include cleaners, sanitizers, and polishes.
Which blood component is more likely to cause infection?
For the past several years, bacterial contamination of platelets has been the greatest transfusion-transmitted infectious risk in the United States; this risk has been significantly higher than the risk of transfusion-transmitted viral infection.
What are the warning signs of a blood infection?
Symptoms include:feeling dizzy or faint.confusion or disorientation.slurred speech.severe muscle pain.severe breathlessness.not urinating for a day.cold, clammy and pale or mottled skin, or grey (ashen) appearance.
What does a contaminated blood culture mean?
Blood culture contamination is defined as the recovery of normal skin flora (coagulase-negative staphylococci, Propionibacterium spp., Aerococcus, Micrococcus, Bacillus spp. [not B. anthracis], Corynebacterium spp. [diphtheroids], and alpha-hemolytic streptococci) from a single blood culture.
What is blood culture contamination?
Blood culture contamination is defined as the presence of microorganisms in the blood culture bottle that entered during sampling but was not actually circulating in the patient’s bloodstream. Healthcare institutions in the United States are held to a performance standard of less than 3% contamination rates for blood culture, 2 but numerous studies have shown contamination rates to be far higher than the 3% standard, with some studies showing as high as, “one-half of all positive blood cultures were judged by infectious disease physicians to represent contamination.” 1 There are many possible sources of blood culture contamination, with some frequent sources including: 1
How does contamination affect the lab?
Contamination can have negative impacts on the lab, hospital system, and patients, with far-ranging consequences such as: 1. Increased staff workload, when many microbiology laboratories struggle with staffing shortages. Unnecessary and expensive additional laboratory testing – up to 80% increase in microbiology charges.
Why is blood culture important?
It is the most important way to diagnose the etiology of bloodstream infections and has major implications for the treatment of those patients . However, blood cultures are frequently contaminated, which can lead to a “false positive” result.
What is blood poisoning?
Blood poisoning is a serious infection. It occurs when bacteria are in the bloodstream.
What is the term for the presence of bacteria in the blood?
The presence of bacteria in the blood is referred to as bacteremia or septicemia . The terms “septicemia” and “sepsis” are often used interchangeably, though technically they aren’t quite the same. Septicemia, the state of having bacteria in your blood, can lead to sepsis.
How to prevent blood poisoning?
The best way to prevent blood poisoning is to treat and prevent infections. It’s also important to prevent any open wounds from becoming infected in the first place with proper cleaning and bandaging. If you’ve had surgery, your doctor will likely prescribe an antibiotic as a precautionary measure against infections.
Why is sepsis more common in hospitalized people?
Because blood poisoning occurs when bacteria enter your bloodstream in conjunction with another infection, you won’t develop sepsis without having an infection first.
Why is it important to treat blood poisoning?
Prompt treatment of blood poisoning is essential because the infection can quickly spread to tissues or your heart valves. Once you’re diagnosed with blood poisoning, you’ll likely receive treatment as an inpatient at a hospital. If you’re showing symptoms of shock, you’ll be admitted to the intensive care unit.
How to tell if you have septicemia?
First, your doctor will perform a physical exam, which will include checking your temperature and blood pressure. If blood poisoning is suspected, your doctor will run tests to look for signs of bacterial infection.
How to treat a septic infection in an immobilized patient?
Blood clots are another concern in immobilized patients. Sepsis is usually treated with hydration, often through an intravenous line, as well as antibiotics that target the organism causing the infection. Sometimes medications may need to be used to temporarily support low blood pressure.
What is the contamination rate of blood culture?
In the past, a blood culture contamination rate of less than 3% was deemed acceptable.
How many times is a blood culture performed?
Blood cultures are a key diagnostic test to detect bacteremia and appropriately treat patients with sepsis and are performed approximately 30 million times in the United States yearly.
What is a phlebotomy team?
Phlebotomy teams: Educate and train individuals who perform blood cultures in aseptic technique.
Is blood culture contamination a clinical problem?
It’s a big deal! Because blood culture contamination is an underappreciated but important clinical problem and because recent studies document it can be markedly decreased, a thorough review of blood culture contamination was recently published:
Can you draw blood cultures through a vascular catheter?
Phlebotomy site: Don’t draw blood cultures through vascular catheters unless the catheter is thought to be the source of sepsis.
Can blood cultures be performed in patients with fungemia?
Patient selection: Blood cultures should only be performed in patients with a reasonable likelihood of bacteremia/fungemia.
Is blood culture contamination bad?
Bottom line: Blood culture contamination is a big deal – resulting in inappropriate antibiotic use and excess hospital stay and economic cost. The long held quality benchmark of 3% contamination should not be complacently tolerated. Through application of comprehensive preventative techniques, blood culture contamination rates of less than 1% should be achievable.
How can hospitals reduce blood culture contamination?
Hospitals may also be able to reduce blood culture contamination rates by utilizing trained phlebotomists or blood culture teams to obtain blood for culture rather than using random nursing personnel, nondegree nursing assistants, medical students, and resident physicians to obtain these specimens. ( 5-7,21) Laboratory-trained phlebotomists and blood culture teams can be better trained and focused on correct antiseptic technique. Additionally, their individual contamination rates can be monitored as part of an institution's performance improvement program.
How do blood cultures help predict infections?
The number of blood cultures that yield a particular organism can help predict true infections. For example, if 2 sets of blood cultures obtained by separate venipunctures in the same time frame are positive with the same organism, the probability of contamination is less than 1 in 1000.
What happened to 2 blood cultures at an ED?
Two days later, 2 out of 2 blood cultures drawn at that ED visit started growing Corynebacterium spp. That evening, the results were reported to a covering physician who was unfamiliar with the patient or previous culture results. The physician assumed that the blood cultures were contaminated from the skin and took no action.
Why should laboratories develop policies and procedures to limit the evaluation of likely contaminants?
Because approximately half of all positive blood cultures in most institutions represent contamination, laboratories should develop policies and procedures to limit the evaluation of likely contaminants. ( 1,5,22) For example, if only a single blood culture grows a coagulase-negative staphylococcus, Bacillus spp., Corynebacterium spp., Propionibacterium spp., viridans group streptococcus, Micrococcus spp., or Aerococcus spp., the likelihood of contamination is high, and full identification of the microorganism as well as susceptibility testing should not be done unless there is direct communication between the physician caring for the patient and the laboratory director. ( 5,11,22)
What is the significance of isolating a microorganism from blood cultures?
Isolation of a microorganism from blood cultures that in most circumstances would represent contamination but, in this instance, represented a clinically important pathogen that caused a potentially life-threatening infection;
Why are blood cultures important?
Physicians and clinical microbiologists have long appreciated that blood cultures are perhaps the most important laboratory tests to diagnose serious infections. In recent years, it has also become apparent that contaminated (i.e., the presence of a pathogen from outside the blood stream) blood cultures are common, leading to falsely positive test results. ( 1,2) Contaminated blood cultures constitute as many as half or more of all positive blood cultures in some centers, are very costly to patients and the health care system, ( 3) and are confusing for clinicians. ( 4,5)
What are the medical errors?
The case history that forms the basis for this commentary illustrates several of the important complexities and inefficiencies of modern medicine, some of which resulted in medical errors. These include: 1 A patient with multiple underlying medical problems that predispose to infection; 2 Isolation of a microorganism from blood cultures that in most circumstances would represent contamination but, in this instance, represented a clinically important pathogen that caused a potentially life-threatening infection; 3 Misinterpretation of the clinical significance of the positive blood culture result; 4 Failure of the primary and covering physicians to communicate effectively, ultimately resulting in delayed diagnosis and increased patient morbidity.
What are some examples of contaminants that may impact laboratory results?
EDTA and IV fluids are just two examples of contaminants that may impact laboratory results. Other examples include additional anticoagulants, such as citrate or heparin, which may interfere with specific lab tests.
What is a compromised sample?
Unfortunately, sample integrity may be compromised in a number of ways that are not immediately obvious. A compromised specimen could include a sample transported at the incorrect temperature, an inappropriate sample type for the test ordered, or a sample “contaminated” with something that could interfere with specific tests. While rarely discussed in the literature, two of the more commonly encountered types of contamination involve ethylenediaminetetraacetic acid (EDTA) and intravenous (IV) fluid contamination.
How to detect EDTA contamination?
Since EDTA is not measured on routine chemistry samples in the laboratory, the most common way to identify sample contamination is to recognize abnormal analyte patterns that suggest its presence . Potassium and calcium are analytes that are routinely measured in many testing panels. Thus, both results are often available in the same specimen. A pattern of extreme hyperkalemia with hypocalcemia should trigger suspicion of EDTA contamination. In addition, the presence of hypomagenesemia, hypozincemia and decreased alkaline phosphatase activity may strengthen this suspicion. While these are some of the more commonly tested analytes that are affected by EDTA contamination, a number of results may be influenced by the presence of EDTA. 4
Why are laboratorians alert to analyte patterns?
In addition to the recognition of general patterns of commonly affected analytes discussed in these examples, other measures may be employed to help identify possible sample contamination, such as delta checks, middleware rules, or comparison with additional tests ordered simultaneously on additional specimens. Since no sample arrives in the lab bearing a label that indicates the presence of a contaminant, laboratorians must remain alert to analyte patterns suggestive of possible sample contamination. This helps ensure that all samples are of the highest quality and only accurate results are being reported.
What are the two analytes that are elevated in IV fluid?
As mentioned, individual analytes may be elevated, or a wide range of analytes may all have low concentrations. Two additional analytes to consider are sodium and chloride. In the presence of IV saline (sodium chloride) contamination, chloride results may appear critically elevated.
Is sodium in IV saline elevated?
In contrast, the concentration of sodium in IV saline approximates physiologic concentrations, and this value may not be elevated in the presence of IV saline contamination.
Is EDTA a contaminant?
EDTA is an anticoagulant commonly used in laboratory testing. EDTA itself is not a contaminant, but may be classified as such depending on the specific testing to be performed on that sample. For example, while test results for many chemistry analytes are adversely affected by the presence of EDTA, this is often the preferred anticoagulant for hematology testing. It is introduced to a sample during the collection process. Contamination may occur if blood tubes are not drawn in the correct order (tubes with additives drawn prior to serum tubes), if an anticoagulated sample is decanted into a different tube type, or if a syringe used to transfer sample between different tube types comes into contact with anticoagulant. 1 Unless a sample arrives in a tube that clearly indicates EDTA is present, there is no visual cue to the lab that some laboratory results may be affected. This means that laboratory personnel must be diligent in deciphering the clues that indicate possible contamination.
