Specimen Labeling & Blood Collection Guidelines PDF

# Specimen Labeling Requirements - Patient's name - Date and time of collection - Initials of the person collecting the specimen If the specimen is one of several, identify each with a separate label designating its source or specimen type. If more than one container must be used (e.g., two jugs f...

# Specimen Labeling Requirements - Patient's name - Date and time of collection - Initials of the person collecting the specimen If the specimen is one of several, identify each with a separate label designating its source or specimen type. If more than one container must be used (e.g., two jugs for a 24-hour urine collection), label as 1 of 2 and 2 of 2 to ensure that they remain together. The person obtaining the specimen should do the specimen labeling. The laboratory policy is to reject any specimen that is not properly labeled. Clients will be notified of any labeling errors and rejected specimens. # Bloodstream Infection ## Blood Collection Guidelines Blood specimen collection is performed routinely to obtain blood for laboratory testing. Blood can be obtained from venous access devices and sometimes by fingerstick. Blood is most frequently obtained via a peripheral vein puncture (venipuncture). Universal precautions help reduce the risk of exposure of the health care professional's skin and/or mucus membranes to infectious materials. It includes the use of a variety of protective barriers, such as gloves, masks, gowns, and eyewear. Good hand washing practices before and after drawing blood also reduce the exposure risk. ### Description Prior to obtaining blood specimens, the nurse should assess the patient, noting factors that may affect test results, including medications, pregnancy, age, and sex. Make sure the patient has followed any special instructions, which could include fasting for a number of hours or taking a medication at a certain time. There are four patient "rights" the nurse should consider when collecting blood specimens. These rights are: - **Right specimen.** Make sure the specimen collected is the specimen ordered. - **Right time.** Certain blood tests must be obtained at specific times. For example, when drawing antibiotic levels, trough specimens should be obtained immediately prior to the next dose. The time to draw peak levels may be dependent upon whether the antibiotic is given intravenously, orally, or intramuscularly. - **Right patient.** Always verify the patient's identification before drawing a blood specimen. The person drawing the specimen should also label the container it is drawn into. - **Right method.** Always follow universal precautions when performing a venipuncture. Before puncturing, the patient's skin should be cleaned. Povidone-iodine (Betadine) can be used, or alcohol. Blood collection tubes come with a variety of colored stopper caps, and may contain additives. The following tubes are the most commonly used types: - **Red top.** This tube contains no additives. It is used for a variety of tests, including blood typing and cross-matching. - **Tiger top or serum separator tube (SST).** This tube contains a polymergel and clot activator. When placed in a centrifuge, the serum is separated out. The SST is commonly used for blood chemistries. - **Lavender top.** These tubes are used primarily for obtaining complete blood counts. They contain EDTA, an anticoagulant additive that chelates calcium. - **Dark green top.** Green top tubes contain the anticoagulant heparin and are often used to obtain lithium and ammonia levels. - **Light blue top.** The light blue top tubes contain sodium citrate, an agent that removes calcium, and are used to obtain protime (PT) and prothrombin time (PTT). - **Light gray top.** This specimen tube contains sodium fluoride and potassium oxylate, antiglycolytic agents that preserve glucose for up to five days. The tube is used primarily to obtain glucose levels. Most laboratory tests are performed on plasma, serum or anticoagulated whole blood. ### Plasma Draw enough blood with the indicated anticoagulant to yield the necessary plasma volume. Gently mix the blood collection tube by inverting six to 10 times immediately after collection. If required, separate plasma from cells by centrifugation within 20 to 30 minutes. ### Serum Using a collection tube with no anticoagulant, draw enough blood to yield the necessary serum volume. Allow blood to clot at room temperature. Separate serum from clot by centrifugation within 20 to 30 minutes. A delay in centrifugation may have a detrimental effect on the sample quality and may result inaccurate results. Avoid hemolysis. ### Whole Blood Draw enough blood with the indicated anticoagulant. Gently mix the blood tube by inverting six to 10 times immediately after collection. The suffix "ernia" is derived from the Greek word meaning "blood"; it refers to the presence of a substance in blood. Bacteremia refers to the presence of bacteria in the blood, whereas fungemia refers to the presence of fungi in the bloodstream. Septicemia means there is a bloodstream infection where bacteria are not only present but are also multiplying and producing toxins. Bacteremia can be transient, intermittent, or continuous. Symptoms of septicemia include fever, chills, and malaise due not only to the presence of the microorganisms but also specifically to the various toxins associated with those organisms. The mortality rate due to septicemia rises with the increasing age of the patient. ### Causative Organisms: The majority of catheter-related bloodstream infections in both adults and children are caused by gram-positive organisms (coagulase-negative staphylococci, S. aureus, and enterococci). Interpretation of blood cultures yielding coagulase-negative staphylococci is difficult. Are these staphylococci true pathogens or is the blood culture contaminated with skin flora? The current recommendation from the Infectious Diseases Society of America is to draw paired blood cultures; one set (aerobic and anaerobic) should be drawn through the intravenous (IV) catheter and one set should be collected by peripheral venipuncture The single most important factor in the detection of bacteremia is adequate blood volume. The total volume of blood collected should be divided between two separate venipunctures to minimize the chance of a false-positive culture due to cutaneous contamination. Single blood cultures have limited clinical utility. Automated blood culture systems have culture botdes that are designed to hold 7 to 10 mL of blood per bottle. To optimize pathogen recovery in an adult, at least 30 mL of blood should be drawn in two venipunctures and distributed evenly between two blood culture sets. Bloodstream infections may also occur as organisms are released from a focus of infection, such as an undrained abscess or infective endocarditis. The primary causes of infective endocarditis are the viridans streptococci from the oral cavity. There is also a group of gram-negative bacilli associated with endocarditis; they are known by the acronym HACEK for Haemophilus aphrophilus, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae. A variety of other organisms can cause bloodstream infections; these include the fungi, viruses, mycobacteria, parasites, and fastidious bacteria. Blood cultures are a primary diagnostic tool if brucellosis is suspected. Communication between the laboratory and physician is vital, however, both for provision of proper culture medium and incubation conditions and for the safety of laboratory personnel. If anthrax is suspected, the clinician needs to communicate this to laboratory personnel. If the patient is immunocompromised and the physician suspects an unusual pathogen, this should be communicated to the laboratory. Incubation times for automated blood culture systems can be modified if the suspect pathogen has a slow growth rate. If the patient is a dialysis patient, recovery of a coagulase-negative staphylococcus could be a significant pathogen rather than a contaminant.