How you can avoid laboratory errors - American Nurse

1 14 American Nurse Today Volume 11, Number 3 wondering: Sincewhen do nurses make laboratoryerrors? Actually, we make themfairly often typically by using im-proper technique when collectingand handling samples and speci-mens. Preanalytic errors (those oc-curring before the sample or speci-men is analyzed) account for 60%to 75% of all lab errors . These er-rors happen before the specimeneven reaches the laboratory , usual-ly during collection. They can leadto incorrect laboratory values witha potentially serious impact.

2 Forinstance, they can result in a mis -diag nosis and inappropriate treat- ment , leading to a life-threateningcondition. Some studies have found highererror rates in blood samples collect-ed by nurses and other non-labora-tory personnel, especially in theemergency department. This hap-pens not from nurses lack of abilitybut from their lack of knowledge ofand adherence to laboratory collec-tion practices. Many factors must beconsidered during blood collection,so the chance of error is high un-less nurses are well educated aboutthe procedure. Common errors inblood sample collection include in-correct identification, wrong tube,insufficient sample quantity, clot-ting, hemolysis, and contamination.

3 Incorrect identificationUnlike some other errors , mislabel-ing of blood samples is 100% pre-ventable. Consequences can be cat-astrophic if the labeling error goesundetected; in some cases, the pa-tient may receive the wrong bloodin a transfusion. Fortunately, the so-lution is simple: Positively identifythe patient and apply the correctsample labels. And never let unla-beled samples or specimens leavethe patient s tube, insufficient sample,and clottingUsing the wrong tube, collecting aninsufficient quantity, and bloodclotting can lead to delays in careand erroneous lab values. Electron-ic systems that generate labelsspecifying which type of tube touse can virtually eliminate wrong-tube errors .

4 Otherwise, consult withthe laboratory if you re unsurewhich tube to use. Also, fill tubes with the recom-mended blood volume. This is es-pecially critical with blue-top tubesused for coagulation studies, be-cause accurate results hinge on theblood-sodium citrate ratio. Transferblood from syringes to tubespromptly and gently invert the tube8 to 10 times to ensure blood ismixed with the additive and to pre-vent clotting. For a summary of keyactions to prevent these errors , seePreventing blood-collection errors . HemolysisNumerous studies have investigatedthe causes of blood sample hemol-ysis, but findings are somewhatcontradictory.

5 Many studies con-cluded that compared to peripheralblood draws, blood withdrawnthrough an catheter is morelikely to lead to hemolysis. Butother studies found no difference,and the vast majority of samplesdrawn by catheter (more than93% in most studies) are not he-molyzed. In light of this successrate, plus certain clinical factors(such as patient anxiety and dis-comfort, as well as the Nurse s riskof a needlestick injury), obviousreasons exist for drawing speci-mens from , take additionalsteps to mitigate risk by using otherhemolysis-reducing strategies asHow you can avoid laboratory errors Phlebotomy education, performance monitoring, and feedback can help nurses avoid potentially seriouslaboratory Jean A.

6 Proehl, RN, MN, CEN, CPEN, FAEN Positively identify the patientwith two identifiers. Verify which tubes are needed. Fill blood tubes in the correct order. Promptly transfer blood with-drawn by syringe into tubes via atransfer device. Fill tubes to the recommendedvolume. If you have trouble ob-taining an adequate sample vol-ume, consider using pediatrictubes. Gently invert blood tubes 8 to 10times to ensure adequate mixingof additive and blood. Label blood tubes at the blood-collection errors March 2016 American Nurse Today 15well.

7 (See Avoiding blood-samplehemolysis.) For instance, keep inmind that red blood cells are frag-ile, so try to decrease the physicalforces transmitted to blood at everystep of the process. If you encoun -ter resistance or turbulence whenwithdrawing blood, reposition theneedle or catheter slightly to im-prove the flow. If this doesn t work,consider discarding that blood sam-ple and changing your phlebotomytechnique. Many clinicians believe certaintypes of equipment can increasehemolysis risk, but conflicting evi-dence exists on the effects of nee-dle gauge, syringes vs. vacuumtubes, low (partial) vacuum tubes,and pneumatic tube systems totransport specimens.

8 Be aware thatdrawing blood through an ex-tension set or a needleless connec-tor hasn t been shown to increasehemolysis. Clearly, no single solu-tion exists for blood-sample hemol-ysis, so be sure to use a multifacto-rial contaminationEach year, more than 1 millionblood cultures in the United Statesare contaminated or produce false-positive results. Contamination maylead to incorrect diagnoses and in-appropriate patient care, increasedmorbidity and mortality, billions ofdollars in additional testing, unnec-essary antibiotic therapy, and ex-tended hospital stays. Longer stays,in turn, increase patients risks foradditional healthcare-related errorsor complications.

9 Inappropriate an-tibiotic use exposes patients to po-tential adverse effects, includingdevelopment of drug-resistant can arise fromequipment or the patient s skin, sobe sure to clean both. First, washyour hands and assemble scrub the tops of culture bot-tles with alcohol and let them airdry. Next, find the venipuncture siteand clean the skin, using alcohol ora chlorhexidine-alcohol solution;both prevent blood-culture contami-nation more effectively than otherskin-preparation solutions. Scrub theskin vigorously for 30 seconds andlet it air dry completely for maxi-mum effect. Unless you re wearingsterile gloves, don t palpate the siteafter it s prepped.

10 (See Preventingblood-culture contamination.)Skin cells can enter the samplefrom the hollow-bore needle punc-ture of the skin, causing contami-nation. To avoid this, divert thefirst 1 to 2 mL of blood away fromthe culture bottle with a discardedsyringe or plain vacuum tube (thetop of which has been preppedwith alcohol). The needle used for venipunc-ture can cause contamination if it sused to inoculate the culture needles before inocula-tion increases the risk of needlestickexposure, so instead use equipmentthat lets you draw the sample di-rectly into the culture bottle. Bacteria colonize cathetersrapidly after insertion.