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Background and aims: The aim of this study was to investigate the possible preanalytical effect of incomplete filling of blood tubes on molecular biology assays. Materials and methods: The study population consisted of 13 healthy volunteers from whom 11 mL of whole blood was collected and then distributed in different volumes (1.5, 3.0, and 6.0 mL, respectively) into three 6.0 mL spray-dried and evacuated K2EDTA blood tubes. Automated RNA extraction was performed using the Maxwell® CSC RNA Blood Kit. DNA was extracted with a MagCorePlusII, with concomitant measurement of glyceralde-hyde-3-phosphate dehydrogenase (GAPDH) gene expression. The nucleic acid concentration was calculated using the NanoDrop 1000 spectrophotometer, and purity was assessed using A260/280 and A260/230 absorbance ratios. Results: The RNA concentration was higher in the tubes filled with 1.5 and 3.0 mL of blood than in the reference 6 mL filled tube. The RNA 260/280 and RNA 260/230 ratios did not differ significantly between the differently filled blood tubes. The DNA concentration remained constant in the differently filled tubes. Compared to the 6.0 mL reference filled tube, the 1.5 mL and 3.0 mL filled blood tubes displayed a lower DNA 260/280 nm ratio. The DNA 260/230 ratio did not differ significantly in any of the variously filled tubes. Compared to the 6.0 mL reference filled blood tube, the 1.5 mL and 3.0 mL filled blood tubes showed a significant increase in the GAPDHcycle threshold. Conclusions: Our results suggest that underfilling of K2EDTA blood tubes may be a modest but analytically significant source of bias in molecular biology testing. [ABSTRACT FROM AUTHOR]

There is limited information on the influence of collecting small amounts of blood on the quality of blood gas analysis. Therefore, the purpose of this study was to investigate the effects of different degrees of underfilling of syringes on test results of venous blood gas analysis. Venous blood was collected by venipuncture from 19 healthcare workers in three 1.0 mL syringes for blood gas analysis, by manually aspirating different volumes of blood (i.e., 1.0, 0.5 and 0.25 mL). Routine blood gas analysis was then immediately performed with GEM Premier 5,000. The results of the two underfilled syringes were compared with those of the reference syringe filled with appropriate blood volume. The values of most assayed parameters did not differ significantly in the two underfilled syringes. Statistically significant variations were found for lactate, hematocrit and total hemoglobin, the values of which gradually increased as the fill volume diminished, as well as for sodium concentration, which decreased in both insufficiently filled blood gas syringes. The bias was clinically meaningful for lactate in syringe filled with 0.25 mL of blood, and for hematocrit, total hemoglobin and sodium in both syringes containing 0.5 and 0.25 mL of blood. Collection of smaller volumes of venous blood than the specified filling volume in blood gas syringes may have an effect on the quality of some test results, namely lactate, hematocrit, total hemoglobin and sodium. Specific indications must be given for standardizing the volume of blood to be collected within these syringes. [ABSTRACT FROM AUTHOR]

Because there is little published evidence on the effects of incomplete filling of K2EDTA evacuated blood tubes on routine hematological testing, this original study aimed to provide updated information on this preanalytical aspect. The study population consisted of 17 ostensibly healthy volunteers. Blood was drawn by venipuncture with a 10 mL syringe and dispensed in varying amounts (0.2, 0.5, 1.0, 2.0, and 3.0 mL) into 3.0 mL blood tubes containing spray-dried 5.4 mg K2EDTA. All tubes were gently mixed and used to perform routine hematology tests on the Sysmex XN-10. Clinically significant variations were defined when the limits of desirable specifications of bias derived from biologic variation were exceeded. The desirable bias was exceeded in 33 % filled tubes (1.0 mL) for hematocrit and MCV (increased values) and for MCHC (decreased values), while it was exceeded in 17 % filled tubes (0.5 mL) for hemoglobin, hematocrit and MCV (increased values), and for MCHC (decreased values). Finally, the variation of values was higher than the desirable bias for RBC, hemoglobin, hematocrit and MCV (increase), and for MCHC and MPV (decrease) in 7 % filled tubes (0.2 mL). No clinically significant variations were observed in tubes filled up to 67 % of their nominal volume (i.e., 2.0 mL). Consideration should be given to reject spray-dried K2EDTA blood tubes that contain a blood volume <67 % of the nominal fill volume, as biased laboratory data in these samples may interfere with clinical decision making and care management. [ABSTRACT FROM AUTHOR]

Background: The use of alternative sample matrices may be an advantageous perspective when the laboratory falls short of serum or lithium-heparin plasma for performing clinical chemistry and/or immunochemistry testing. This study was aimed at exploring whether some tests may be performed in citrate plasma as an alternative to lithium-heparin plasma. Methods: Paired lithium-heparin and citrate plasma samples collected from 55 inpatients were analyzed on Roche Cobas 8000 for 28 different clinical chemistry and immunochemistry parameters. Data obtained in citrate plasma were adjusted for either the dilution factor or using an equation corresponding to the linear regression calculated by comparing unadjusted lithium-heparin and citrate plasma values. Results: Except for magnesium (+17%) and sodium (+11%), unadjusted values of all remaining analytes were significantly lower in citrate than in lithium-heparin plasma, with bias ranging between −6.4% and −25.9%. The correlation between lithium-heparin and citrate plasma values was generally excellent (i.e. >0.90). The adjustment of citrate plasma values for the dilution factor (i.e. 1.1) was only effective in harmonizing the results of albumin and lipase, whilst the concentration of all other analytes remained significantly different between the two sample matrices. The adjustment of plasma citrate values using corrective formulas was instead effective in harmonizing all parameters, with no results remaining statistically different between the two sample matrices. Conclusions: Citrate plasma may be used in exceptional circumstances for clinical chemistry and immunochemistry testing as a replacement for lithium-heparin plasma, provided that citrate plasma values are adjusted by using validated corrective equations. [ABSTRACT FROM AUTHOR]

Introduction: Pediatric tubes are increasingly used for drawing blood for hemostasis testing. This study has investigated the potential impact of low volume citrate tubes on results of first‐line hemostasis testing. Methods: The study population comprised 34 patients on warfarin therapy and 17 ostensibly healthy volunteers. Blood was collected into five different evacuated blood tubes from each subject. On right arm, blood was drawn directly into two standard evacuated blood tubes (3‐mL Vacuette and 2‐mL Vacutest) and one evacuated low volume blood tube (1‐mL Vacuette) by straight needle venipuncture. On left arm, blood was drawn using a 5‐mL syringe and then transferred within two nonevacuated microtubes (0.5 mL MiniCollect and 0.5 mL Micro Test). Prothrombin time (PT), activated partial thromboplastin time (APTT), and fibrinogen were assayed on ACL TOP 700. Results: Spearman's correlation of PT, APTT, and fibrinogen values obtained using different tubes was always satisfactory (ie, ≥0.93). A statistically significant bias was frequently found by comparing values obtained in different tubes. Nevertheless, the minimum quality specifications for bias were exceeded only by comparing data of Vacuette 1 mL with those of all other blood tubes for PT, by comparing data of Micro Test 0.5 mL with those of all other blood tubes for APTT, and by comparing data of Micro Test 0.5‐mL blood tubes with those of Vacuette 3 mL and Vacuette 1. Conclusion: First‐line hemostasis testing using low volume citrate tubes may display differences sometimes exceeding the minimum quality specifications. [ABSTRACT FROM AUTHOR]

A 51-year old male patient was admitted to the hospital with acute dyspnea and history of chronic asthma. Venous blood was drawn into a 3.0 mL heparinized syringe and delivered to the laboratory for blood gas analysis (GEM Premier 4000, Instrumentation Laboratory), which revealed high potassium value (5.2 mmol/L; reference range on whole blood, 3.5-4.5 mmol/L). This result was unexpected, so that a second venous blood sample was immediately drawn by direct venipuncture into a 3.5 mL lithium-heparin blood tube, and delivered to the laboratory for repeating potassium testing on Cobas 8000 (Roche Diagnostics). The analysis revealed normal plasma potassium (4.6 mmol/L; reference range in plasma, 3.5-5.0 mmol/L) and haemolysis index (5; 0.05 g/L). Due to suspicion of spurious haemolysis, heparinized blood was transferred from syringe into a plastic tube and centrifuged. Potassium and haemolysis index were then measured in this heparinized plasma, confirming high haemolysis index (50; 0.5 g/L) and pseudohyperkalemia (5.5 mmol/L). Investigation of this case revealed that spurious haemolysis was attributable to syringe delivery in direct ice contact for ~15 min. This case emphasizes the importance of avoiding sample transportation in ice and the need of developing point of care analysers equipped with interference indices assessment. [ABSTRACT FROM AUTHOR]

Background: Although it is known that glucose concentration exhibits a time-dependent decay in uncentrifuged serum and lithium-heparin blood tubes, no evidence exists on how this variation may depend on blood cell counts (CBC) and volumes. Methods: Venous blood was drawn from 30 non fasting healthy volunteers into three serum and three lithium-heparin tubes. One serum and lithium-heparin tubes were centrifuged within 15 min after collection and glucose was measured with a hexokinase assay. The second and third serum and lithium-heparin tubes were maintained at room temperature for 1 and 2 h after the first tubes were centrifuged. These other tubes were then centrifuged and glucose was measured. CBC was performed in the first lithium-heparin tube, before centrifugation. Results: The mean decrease of glucose was higher in lithium-heparin plasma than in serum (0.33 vs. 0.24 mmol/L/h; p<0.001). Glucose concentration decreased by 7% and 5% per hour in lithium-heparin plasma and serum, respectively. In univariate analysis, the absolute decrease of glucose concentration was associated with sex (higher in men than in women), red blood cell (RBC) count, hematocrit, white blood cell (WBC) count, neutrophils and monocytes in both lithium-heparin plasma and serum. In multivariate analysis, the decrease of glucose concentration remained independently associated with RBC, WBC, neutrophils and monocytes in both sample matrices. No significant association was found with platelet number and erythrocyte or platelet volume. Conclusions: Glucose concentration decrease in uncentrifuged lithium-heparin and serum tubes depends on the baseline number of RBC, WBC, neutrophils and monocytes within the tubes. [ABSTRACT FROM AUTHOR]

Background To investigate the influence of different phlebotomy postures on clinical chemistry testing. Materials and methods Nineteen volunteers were recruited from the laboratory staff. A first set of samples was drawn after 25 min of resting in supine position, a second after 20 min in sitting position, and a third after 20 min in upright position. Clinical chemistry testing was performed on Roche Cobas C501. Results The plasma volume change (PVC) was − 3.4% from supine to sitting, − 14.1% from supine to standing and − 9.7% from sitting to standing. Compared to quality specifications for bias, hemoglobin, hematocrit, albumin and total proteins exhibited meaningful increases from supine to sitting, whereas meaningful increases were observed for hemoglobin, hematocrit, albumin, alkaline phosphatase (ALP), amylase, aspartate aminotransferase (AST), total bilirubin, calcium, total and high-density lipoprotein (HDL) cholesterol, gamma-glutamyl transferase (GGT), glucose, lactate dehydrogenase (LDH), magnesium, total protein and triglycerides from sitting to standing. The parameters with meaningful bias from sitting to upright were hemoglobin, hematocrit, albumin, ALP, total bilirubin, calcium, total and HDL cholesterol, glucose, LDH and total protein. Conclusions These results provide further support to the need of standardizing patient's posture during phlebotomy. [ABSTRACT FROM AUTHOR]

Int roduction: The contamination of serum or lithium heparin blood with ethylenediaminetetraacetic acid (EDTA) salts may affect accuracy of some critical analytes and jeopardize patient safety. The aim of this study was to evaluate the effect of lithium heparin sample contamination with different amounts of K2EDTA. Materials and methods: Fifteen volunteers were enrolled among the laboratory staff. Two lithium heparin tubes and one K2EDTA tube were collected from each subject. The lithium-heparin tubes of each subject were pooled and divided in 5 aliquots. The whole blood of K2EDTA tube was then added in scalar amount to autologous heparinised aliquots, to obtained different degrees of K2EDTA blood volume contamination (0%; 5%; 13%; 29%; 43%). The following clinical chemistry parameters were then measured in centrifuged aliquots: alanine aminotranspherase (ALT), bilirubin (total), calcium, chloride, creatinine, iron, lactate dehydrogenase (LD), lipase, magnesium, phosphate, potassium, sodium. Results: A significant variation starting from 5% K2EDTA contamination was observed for calcium, chloride, iron, LD, magnesium (all decreased) and potassium (increased). The variation of phosphate and sodium (both increased) was significant after 13% and 29% K2EDTA contamination, respectively. The values of ALT, bilirubin, creatinine and lipase remained unchanged up to 43% K2EDTA contamination. When variations were compared with desirable quality specifications, the bias was significant for calcium, chloride, LD, magnesium and potassium (from 5% K2EDTA contamination), sodium, phosphate and iron (from 29% K2EDTA contamination). Conclusions: The concentration of calcium, magnesium, potassium, chloride and LD appears to be dramatically biased by even modest K2EDTA contamination (i.e., 5%). The values of iron, phosphate, and sodium are still reliable up to 29% K2EDTA contamination, whereas ALT, bilirubin, creatinineand lipase appear overall less vulnerable towards K2EDTA contamination. [ABSTRACT FROM AUTHOR]

Background This study was planned to establish whether random orientation of gel tubes after centrifugation may impair sample quality. Materials and methods Eight gel tubes were collected from 17 volunteers: 2 Becton Dickinson (BD) serum tubes, 2 Terumo serum tubes, 2 BD lithium heparin tubes and 2 Terumo lithium heparin tubes. One patient's tube for each category was kept in a vertical, closure-up position for 90 min ("upright"), whereas paired tubes underwent bottom-up inversion every 15 min, for 90 min ("inverted"). Immediately after this period of time, 14 clinical chemistry analytes, serum indices and complete blood count were then assessed in all tubes. Results Significant increases were found for phosphate and lipaemic index in all inverted tubes, along with AST, calcium, cholesterol, LDH, potassium, hemolysis index, leukocytes, erythrocytes and platelets limited to lithium heparin tubes. The desirable quality specifications were exceeded for AST, LDH, and potassium in inverted lithium heparin tubes. Residual leukocytes, erythrocytes, platelets and cellular debris were also significantly increased in inverted lithium heparin tubes. Conclusions Lithium heparin gel tubes should be maintained in a vertical, closure-up position after centrifugation. [ABSTRACT FROM AUTHOR]

Background: It is still uncertain whether or not avoidance to let disinfectant alcohol dry at the site of venipuncture is a source of spurious hemolysis when drawing venous blood. Methods: In a consecutive series of 52 outpatients referred for routine laboratory testing, venous blood was drawn by direct venipuncture with (odd group) or without (pair group) wiping 70% isopropyl alcohol at the site of venipuncture. A 3.5 mL evacuated tube with clot activator and gel separator was drawn from a vein of the upper limb, serum was immediately separated with standard centrifugation and tested for potassium, lactate dehydrogenase (LD), aspartate aminotransferase (AST) and hemolysis index (HI) on Roche Cobas. Results: No specimen was discarded for unsatisfactory venipuncture. No differences for age and gender were observed between groups. As regards the four parameters investigated, no significant differences could be observed between patients in whom blood was drawn with or without letting the alcohol dry. It is also noteworthy that no sample in both groups exceeded the conventional sample rejection threshold of cell-free hemoglobin. Conclusions: The results of our prospective, randomized study attest that failure to wipe alcohol at the site of venipuncture should not be considered as a potential source of spurious hemolysis when drawing blood. [ABSTRACT FROM AUTHOR]

Preanalytical activities, especially those directly connected with blood sample collection and handling, are the most vulnerable steps throughout the testing process. The receipt of unsuitable samples is commonplace in laboratory practice and represents a serious problem, given the reliability of test results can be adversely compromised following analysis of these specimens. The basic criteria for an appropriate and safe venipuncture are nearly identical to those used for collecting blood for clinical chemistry and immunochemistry testing, and entail proper patient identification, use of the correct technique, as well as appropriate devices and needles. There are, however, some peculiar aspects, which are deemed to be particularly critical when collecting quality specimens for clot-based tests, and these require clearer recognition. These include prevention of prolonged venous stasis, collection of nonhemolyzed specimens, order of draw, and appropriate filling and mixing of the primary collection tubes. All of these important preanalytical issues are discussed in this article, and evidence-based suggestions as well as recommendations on how to obtain a high-quality sample for coagulation testing are also illustrated.We have also performed an investigation aimed to identify variation of test results due to underfilling of primary blood tubes, and have identified a clinically significant bias in test results when tubes are drawn at less than 89% of total fill for activated partial thromboplastin time, less than 78% for fibrinogen, and less than 67% for coagulation factor VIII, whereas prothrombin time and activated protein C resistance remain relatively reliable even in tubes drawn at 67% of the nominal volume. [ABSTRACT FROM AUTHOR]

Objective: Blood collection is a critical part of the preanalytical phase of laboratory testing. Only a few procedures are evaluable for detecting errors in this non-automatic activity. Information about potential sources of error is frequently absent from quality-control procedures and training materials. Objective: To evaluate the performance of phlebotomists and to identify the major sources of errors during diagnostic blood collection. Methods: We evaluated the performance of 3 phlebotomists each from 10 laboratories regarding tourniquet time, request for fist clenching, excessive friction during skin cleaning, sequence of vacuum-tube usage, and mixing of tube contents after specimen collection. The total number of these laboratories represented an equal number of private (ie, owned by private parties) and public (ie, administration by government organizations) settings. Results: An error rate of greater than 60% was observed in the performance of procedures we examined, and the error rate was not significantly different between public and private settings other than more adequate mixing of the contents of primary collection tubes in private facilities. Conclusions: Most facilities did not achieve adequate quality standards in phlebotomy. In procedural manuals, training materials and practices for phlebotomists, greater emphasis should be placed on presenting information on possible sources of error and on the correct implementation of procedures that ensure the quality of diagnostic blood specimens collected for laboratory analysis. [ABSTRACT FROM AUTHOR]

Control and standardization of preanalytical variability is a critical factor for achieving accuracy and precision in laboratory testing. Although venous stasis from tourniquet placement during venepuncture should be minimized, as it has been claimed to account for spurious and significant variations for several analytes in plasma, there is controversy surrounding its real impact on laboratory testing. The aim of the present study was the investigation of the influence of short-term venous stasis on routine biochemical testing, by measuring the plasma concentration of 12 common analytes, including proteins, protein-bound substances, enzymes and electrolytes, in plasma specimens collected either without venous stasis or following the application of standardized external pressure of 60 mm Hg using a sphygmomanometer for 1 and 3 min. Although the overall correlation between measures was acceptable, the pattern of change was mostly dependent on the length of stasis, size and protein-binding characteristics of the analytes, achieving clinical significance for albumin, calcium and potassium after 1-min stasis, and alanine aminotransferase, albumin, calcium, chloride, total cholesterol, glucose and potassium after 3-min stasis. Statistically significant differences could be observed in seven (alanine aminotransferase, albumin, calcium, total cholesterol, creatine kinase, iron and potassium) and ten (alanine aminotransferase, albumin, calcium, chloride, total cholesterol, creatine kinase, creatinine, glucose, iron and potassium) out of the 12 analytes tested, after 1- and 3-min venous stasis, respectively. The most clinically significant changes from standard venepuncture, when compared to the current analytical quality specifications for desirable bias, occurred for potassium (1-min stasis, −2.8%; 3-min stasis, −4.8%, both p<0.001), calcium (1-min stasis, +1.6%, p<0.05; 3-min stasis, +3.6%, p<0.001) and albumin (1-min stasis, +3.5%; 3-min stasis, +8.6%, both p<0.001). As most of these effects are dependent on the stasis time during venepuncture and biochemical or physiological characteristics of the analyte, these variations could likely be anticipated, allowing the most appropriate preventive measures to be adopted. [ABSTRACT FROM AUTHOR]

The predominant technique used to draw blood for laboratory testing is a conventional straight needle attached to an evacuated tube system. However, alternative tools might be advantageous in exceptional circumstances. The use of butterfly devices has been traditionally discouraged for reasons of costs and due to the high risk of obtaining unsuitable samples, but there is no convincing evidence to support the latter indication. The purpose of this study was to compare results of hematological and clinical chemistry testing, after drawing blood into evacuated tubes, employing either a traditional 21-gauge straight needle or a 21-gauge butterfly device with 300-mm-grade polyvinyl chloride tubing. Blood samples and complete sets of data were successfully obtained for 30 consecutive outpatients. Of the 43 hematological and clinical chemistry parameters measured, means for paired samples collected by the two alternative drawing techniques did not differ significantly, except for serum sodium, white blood cells and platelets counts. Bland-Altman plots and limits-of-agreement analysis showed mean bias of between -7.2% and 1.7% and relative coefficients of variation ranging from 0.2% to 21.2%. The 95% agreement interval in the set of differences was acceptable and was mostly within the current analytical quality specifications for desirable bias. The rate of hemolysis in plasma was not statistically different between the two collection techniques. Taken together, the results of the present investigation suggest that, when a proper technique is used and within certain limitations, the butterfly device may be a reliable alternative to the conventional straight needle to draw blood for laboratory testing. [ABSTRACT FROM AUTHOR]

Background: Clinical chemistry testing is influenced by a variety of preanalytical variables, including sample preparation. The presence of a diluted plasma layer at the top of primary tubes containing plasma citrate has recently been reported. However, no indication is available so far on the potential non-homogeneous distribution of clinical chemistry analytes during centrifugation of primary tubes containing lithium-heparin as an additive. Methods: A total of 40 lithium-heparin plasma samples were collected from volunteers and immediately centrifuged. An aliquot was obtained from the upper 0.4 mL of plasma (upper aliquot), 1.0 mL of plasma was discarded, and a second aliquot (lower aliquot) was obtained from the remaining plasma. The concentrations of alanine aminotransferase, albumin, alkaline phosphatase, amylase, amylase pancreatic, aspartate aminotransferase, direct bilirubin, total bilirubin, blood urea nitrogen, calcium, chloride, cholesterol, C-reactive protein (CRP), creatinine, creatine kinase, γ-glutamyltransferase (GGT), glucose, high-density lipoprotein-cholesterol, iron, lactate dehydrogenase (LDH), magnesium, phosphate, potassium, total protein, sodium, triglycerides and uric acid were assayed on a Roche/Hitachi Modular System P according to the manufacturer's specifications and using proprietary reagents. Sodium, chloride and potassium were measured on a Roche/Hitachi Modular System using indirect ion-selective electrode methods. Results: We observed a statistically significant difference between the upper and lower aliquots for CRP (3.88±0.67 vs. 3.94±0.68 mg/L; p=0.025), GGT (32.1±8.0 vs. 31.8±8.0 U/L; p=0.013), LDH (395±19 vs. 386±20 U/L; p=0.010) and triglycerides (1.29±0.09 vs. 1.27±0.09 mmol/L; p=0.001); results for the other analytes were not significantly different. In no case did the mean percentage bias recorded between aliquots exceed the current analytical quality specifications for desirable bias. Conclusions: The results of our investigation show that plasma layer stratification might occur in primary lithium-heparin tubes for a limited number of routine clinical chemistry tests, introducing a statistically significant bias in the measurement of GGT, LDH, triglycerides and CRP in the upper vs. the bottom section. When delayed testing is necessary for these parameters, we suggest that plasma should be separated after centrifugation and appropriately mixed before delayed/repeated analysis or aliquoting. Clin Chem Lab Med 2008;46:1180–2. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To assess prevalence of interference from hemolysis, lipaemia, icterus in arterial blood gas analysis (ABG). Design: Serum indices (SI) were assessed in the plasma of ABG samples over a 2-month period. Results: Out of a total of 478 ABG specimens, we identified 17 hemolyzed samples (4%), 52 (11%) with lipaemia, and 63 (13%) with icterus. Conclusion: Test results on a considerable number of ABG specimens might be unreliable due to presence of interference. [Copyright &y& Elsevier]

Introduction: The validation process is essential in accredited clinical laboratories. Aim of this study was to validate five kinds of serum vacuum tubes for routine clinical chemistry laboratory testing. Materials and methods: Blood specimens from 100 volunteers in five different serum vacuum tubes (Tube I: VACUETTE®, Tube II: LABOR IMPORT®, Tube III: S-Monovette®, Tube IV: SST® and Tube V: SST II®) were collected by a single, expert phlebotomist. The routine clinical chemistry tests were analyzed on cobas® 6000 module. The significance of the differences between samples was assessed by paired Student’s t-test after checking for normality. The level of statistical significance was set at P < 0.005. Finally, the biases from Tube I, Tube II, Tube III, Tube IV and Tube V were compared with the current desirable quality specifications for bias (B), derived from biological variation. Results and conclusions:Basically, our validation will permit the laboratory or hospital managers to select the brand’s vacuum tubes validated according him/her technical or economical reasons, in order to perform the following laboratory tests: glucose, total cholesterol, high density lipoprotein-cholesterol, triglycerides, total protein, albumin, blood urea nitrogen, uric acid, alkaline phosphatise, aspartate aminotransferase, gamma-glutamyltransferase, lactate dehydrogenase, creatine kinase, total bilirubin, direct bilirubin, calcium, iron, sodium and potassium. On the contrary special attention will be required if the laboratory already performs creatinine, amylase, phosphate and magnesium determinations and the quality laboratory manager intend to change the serum tubes. We suggest that laboratory management should both standardize the procedures and frequently evaluate the quality of in vitro diagnostic devices. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Evaluate whether four different brands/types of heparin coated syringes can represent a source of variability in blood gas analysis (BGA). Design and methods: Blood was collected from one hundred volunteers into different syringes: Syringe I (lithium heparin and calcium balanced); Syringe II: in-house prepared (sodium heparin); Syringe III: (spray-dried calcium-balanced lithium heparin); Syringe IV (lyophilized electrolyte-balanced lithium heparin). Results: Significant differences were as follows: a) Syringe I vs II: pO2, sO2, pCO2 t, cHCO3 −, ctCO2, base excess (BE), total hemoglobin (tHb), sodium (Na+), potassium (K+), calcium (Ca2+), glucose (Glu), lactate (Lac), O2 Hb and p 50; b) Syringe I vs III: pH, pO2, cHCO3 −, ctCO2, BE, Na+, Glu, Lac and p 50; c) Syringe I vs IV: pH, pO2, sO2, pCO2 t, BE, Na+, K+, Ca2+, Glu, Lac and O2 Hb; d) Syringe II vs III: pH, pO2, sO2, pCO2 t, cHCO3 −, ctCO2, ctO2, tHb, Na+, K+, Ca2+, Lac and p 50; e) Syringe II vs IV: pH, pO2, sO2, pCO2 t, cHCO3 −, ctCO2, BE, tHb, Na+, K+, Ca2+, Lac, O2 Hb and p 50; f) Syringe III vs IV: pH, pO2, sO2, cHCO3 −, ctCO2, ctO2, BE, Na+, K+, Ca2+, O2 Hb and p 50. Conclusion: The different manufacturers of syringes can represent new source of variability on BGA. [Copyright &y& Elsevier]

Abstract: Background: The hemolysis index (HI) is now available in several laboratory analyzers, but doubts remain about the thresholds for suppressing test results, the degree of standardization among different instrumentations and the use of different reference ranges in different biological matrices. This study was hence planned to establish the reference ranges of HI in serum and lithium-heparin plasma in a population of unselected outpatients, using two analytical platforms. Materials and methods: We analyzed the HI in serum and lithium-heparin samples collected from 135 unselected outpatients, and we also defined the relative reference ranges according to Clinical and Laboratory Standards Institute (CLSI) recommendations. Samples were collected in the morning by expert nurses, using straight needle venipuncture. The HI in serum and lithium-heparin plasma was assessed with Roche Cobas c501 and Siemens Dimension Vista 1500. Results: The median concentration of cell-free hemoglobin was significantly higher in serum than in lithium-heparin plasma when measured with Cobas c501, but not with Dimension Vista 1500. After categorizing values according to cell-free hemoglobin thresholds, the agreement between instruments was 0.75 (p<0.01) for serum and 0.95 (p<0.01) for lithium-heparin plasma. The upper limits calculated according to CLSI document C28-A3 were 0.22g/L for Roche Cobas c501 and 0.25g/L for Siemens Dimension Vista 1500 in serum, whereas they were 0.13g/L for Cobas c501 and 0.10g/L for Dimension Vista 1500 in lithium-heparin plasma. Conclusions: According to our data, different thresholds of cell-free hemoglobin should be used between serum and lithium-heparin plasma for monitoring phlebotomy practice. [Copyright &y& Elsevier]

Abstract: Objectives: Despite manufacturers' claim that systematical assessment of serum indices does not impact on testing efficiency, there is widespread perception that this practice may increase the turnaround time (TAT). A multicenter investigation was planned to verify TAT and performance of serum indices on five different clinical chemistry analyzers. Design and methods: Twenty study samples prepared from pooled sera of outpatients, emergency department, intensive care unit and dialyzed patients were divided in aliquots and shipped to 5 different laboratories. According to local instrumentation (Beckman Coulter AU5800, Roche Cobas 6000, Siemens Dimension Vista 1500, Abbott Architect c 16000 and Ortho Vitros 5.1/FS) and reagents, 13 clinical chemistry parameters were assayed on all study samples, with or without contextual assessment of serum indices. Results: The TAT with assessment of serum indices modestly or even negligibly increased, and varied from −0.2 to +5.0% (i.e., from −3 to +85s). When using the lowest thresholds for sample acceptability, the agreement of hemolysis index (HI) among different instruments was comprised between 0.62 and 1.00 (all p<0.01), but was higher than 0.80 in only 4/10 cases. The agreement of icteric and lipaemic indices could not be estimated due to the low number of samples exceeding acceptability criteria. Conclusions: The results of this study confirm that systematical measurement of serum indices does not impair instrument efficiency. The comparison of HI also suggests that major harmonization may be advisable for this measure among different manufacturers and instrumentations. [Copyright &y& Elsevier]

Abstract: Background: Safety transport boxes are increasingly used to ship laboratory specimens but there is little information on their capacity to maintain suitable transportation temperatures. Materials and methods: Inner temperature was assessed using a commercially available transport box during an 8-h transportation period in the heat. Results: Temperature stability was unsatisfactory during approximately 64% of the transportation time (i.e., from 125 to 450min). Conclusions: Transport boxes might be unsuitable for shipping specimens over long periods. [Copyright &y& Elsevier]