Incorrect order of draw could be mitigate the patient safety: a phlebotomy management case report
A 45 years old male outpatient, with no apparent clinical complaints, wheelchair dependent, calls to our laboratory accredited by DICQ® (DICQ is a National System of Accreditation from Brazilian Society of Clinical Analyses based on ISO 15189 document), asking for a blood specimen collection at home, for performing a series of routine laboratory tests prescribed by his physician. The tests are the: total cholesterol (CHOL), HDL-cholesterol (HDL), triglycerides (TG), sodium (Na), potassium (K), total calcium (tCa), free calcium (fCa), urea, creatinine (CREA), total protein (TP), albumin (ALB), alkaline phosphatase (ALP) and routine blood count with platelets (CBC). The patient was asked to observe 12-hours overnight fasting and the blood collection was scheduled for 7 am, 3 work days after his call. Before blood collection, the median cubital vein was located on the left forearm using only a subcutaneous tissue transilluminator device (Venoscópio IV plus, Duan do Brasil, Sao Paulo, Brazil) –without tourniquet – to prevent interference from venous stasis (–), and blood samples were collected using a 20-G straight needle (BD Vacuntainer ® Becton, Dickinson and Company Franklin Lakes, NJ, USA) connected to the holder, directly into the vacuum tubes (Greiner Bio-One GmbH, Kremsmünster, Austria). The order of different types of tube filling was: a) clot activator and gel separator tube, b) K3EDTA tube for CBC and c) a blood gas dedicated-syringe (Pico 50® with 80 I.U. lyophilized electrolyte-balanced lithium heparin, Radiometer Medical ApS, Denmark) without needle, which was directly connected to the needle-holder system in order to avoid double vein puncture. After collection, the tubes were properly mixed and transported from patient’s house to the core laboratory by car at 20 ± 2 °C in upright position inside a transport box. The blood into syringe was transported at 4 ± 1 °C, as recommended by clinical laboratory standard institute C31-A2 document (). The blood specimens (serum tube, cell blood count tube and dedicated syringe) arrived in core laboratory about one hour after blood collection and were immediately processed and analyzed (< 15 min from the arrival time). The dedicated syringe was properly mixed and the free calcium was measured by ion-selective electrode on ABL 700® (Radiometer Medical ApS, Brønshøj, Denmark), according to the manufacturer’s specifications and using proprietary reagents. Whole blood for CBC was gently mixed and analyzed on Sysmex® XE-2100D, Automated Hematology Analyzer (Sysmex Corporation®, Kobe, Japan). Serum vacuum tube was centrifuged at 1500 x g for 10min at room temperature. In sequence, the laboratory tests on serum were performed on the primary blood tube on Cobas® 6000 < c501 > module (Roche Diagnostics GmbH, Penzberg, Germany), according to the manufacturer’s specifications and using proprietary reagents. All laboratory instruments had been previously calibrated against appropriate proprietary reference standard material and verified with the use of proprietary controls. Our evaluation of the within-run precision by internal quality control is shown as coefficients of variation (CVa). The results are shown in . The laboratory staff (clinical chemistry specialist) contacted the patient by phone because some results (i.e. potassium, total calcium and free calcium) of the sample collected in dedicated syringe were out of the critical limits established by Kost (,). The patient reported that he did not use topical medicines or intravenous solution in the last four months. A new blood collection (serum tube and dedicated syringe only) was scheduled for 12.30 pm of the same day. The venipuncture for the 2nd blood collection was performed, by the same phlebotomist, in cephalic vein on the left forearm. The drawing order was: a) clot activator and gel separator tube, b) blood gas dedicated-syringe; both of the same brand and lot used for the first blood collection. So, during the 2nd venipuncture the diagnostic blood specimen collection did not include a new EDTA vacuum tube. The following procedures were identical to the described above for the 1st blood specimen collection. The 2nd blood specimens arrived in core laboratory about 45 min after collection and were immediately processed and analyzed on the same analytical instruments. The results are shown in .