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1.  Could light meal jeopardize laboratory coagulation tests? 
Biochemia Medica  2014;24(3):343-349.
Presently the necessity of fasting time for coagulation tests is not standardized. Our hypothesis is that this can harm patient safety. This study is aimed at evaluating whether a light meal (i.e. breakfast) can jeopardize laboratory coagulation tests.
Materials and methods:
A blood sample was firstly collected from 17 fasting volunteers (12 h). Immediately after blood collection, the volunteers consumed a light meal. Then samples were collected at 1, 2 and 4 h after the meal. Coagulation tests included: activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen (Fbg), antithrombin III (AT), protein C (PC) and protein S (PS). Differences between samples were assessed by Wilcoxon ranked-pairs test. The level of statistical significance was set at P < 0.05. Mean % differences were determined and differences between and baseline and 1, 2 and 4h samples were compared with reference change value (RCV).
A significantly higher % activity of AT was observed at 1 h and 4 h after meal vs. baseline specimen [113 (104–117) and 111 (107–120) vs. 109 (102–118), respectively; P = 0.029 and P = 0.016]. APTT at 2 h was found significantly lower than baseline samples [32.0 (29.9–34.8) vs. 34.1 (32.2–35.2), respectively; P = 0.041]. The results of both Fbg and PS tests were not influenced by a light meal. Furthermore, no coagulation tests had significant variation after comparison with RCV.
A light meal does not influence the laboratory coagulation tests we assessed, but we suggest that the laboratory quality managers standardize the fasting time for all blood tests at 12 hours, to completely metabolize the lipids intake.
PMCID: PMC4210254  PMID: 25351352
diagnostic errors; fasting; postprandial period; reference values; reproducibility of results
2.  The uptake of different iron salts by the yeast Saccharomyces cerevisiae 
Brazilian Journal of Microbiology  2014;45(2):491-494.
Yeasts can be enriched with microelements, including iron; however, special physicochemical conditions are required to formulate a culture media that promotes both yeast growth and iron uptake. Different iron sources do not affect biomass formation; however, considering efficacy, cost, stability, and compatibility with Saccharomyces cerevisiae metabolism, ferrous sulphate is recommended.
PMCID: PMC4166273  PMID: 25242932
yeast; Saccharomyces cerevisiae; iron uptake; iron sources; biomass formation
3.  Quality Impact on Diagnostic Blood Specimen Collection Using a New Device to Relieve Venipuncture Pain 
A new device called Buzzy® has been recently presented that combines a cooling ice pack and a vibrating motor in order to relieve the venipuncture pain. The aim of this study was to evaluate the impact of Buzzy® use during diagnostic blood specimen collection by venipuncture for routine immunochemistry tests. Blood was collected from 100 volunteers by a single, expert phlebotomist. A vein was located on the left forearm without applying tourniquet, in order to prevent any interference from venous stasis, and blood samples were collected using a 20-G straight needle directly into 5 mL vacuum tubes with clot activator and gel separator. In sequence, external cold and vibration by Buzzy® was applied on the right forearm—5 cm above the chosen puncture site—for 1 min before venipuncture and continued until the end of the same procedure already done in the left forearm. The panel of tests included the following: glucose, total cholesterol, HDL-cholesterol, triglycerides, total protein, albumin, c-reactive protein, urea, creatinine, uric acid, alkaline phosphatase, amylase, AST, ALT, g-glutamyltransferase, lactate dehydrogenase, creatine kinase, total bilirubin, phosphorus, calcium, magnesium, iron, sodium, potassium, chloride, lipase, cortisol, insulin, thyroid-stimulating hormone, total triiodothyronine, free triiodothyronine, total thyroxine, free thyroxine and haemolysis index. Clinically significant differences between samples were found only for: total protein, albumin and transferrin. The Buzzy® can be used during diagnostic blood specimens collection by venipuncture for the majority of the routine immunochemistry tests. We only suggest avoiding this device during blood collection when protein, albumin and transferrin determinations should be performed.
PMCID: PMC3689328  PMID: 24426217
Clinical chemistry tests; Laboratory error; Patient safety; Phlebotomy; Preanalytical variability; Reproducibility of results
4.  Assessing the adherence to and the therapeutic effectiveness of hypolipidemic agents in a population of patients in Brazil: a retrospective cohort study 
Pharmacy Practice  2014;12(2):378.
to evaluate the relation between patient adherence and therapeutic effectiveness of hypolipidemic agents in clinical practice.
A retrospective cohort study of 417 patients using hypolipidemic drugs (simvastatin, atorvastatin) between 2003 and 2010 was performed. The population studied consists of patients assisted by the Public Health Service in the far-west region of the State of Santa Catarina, Brazil. The Medication Possession Ratio obtained from pharmacy refill data was used to measure patient adherence. Therapeutic effectiveness was evaluated based on the difference obtained in the serum levels of total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides, before and after taking the drug, in an average time of 8.3 months.
Following the treatment with hypolipidemic agents, it has been observed a reduction of 14.3% for total cholesterol, 19.6% for LDL-cholesterol, and 14.4% for triglycerides. HDL-cholesterol increased by an 8.0% average. The major changes in lipid profile were promoted by atorvastatin 20 mg daily. The medication adherence rate decreased over the monitoring period. Adherence rates below 60% were associated with therapeutic failure, while rates equal to 80% or higher were associated with the best response to the lipid-lowering drugs.
Adherence to hypolipidemic agents is higher at the beginning of the treatment, but it decreases over time, affecting the achievement of therapeutic goals.
PMCID: PMC4100947  PMID: 25035713
Medication Adherence; Hypolipidemic Agents; Outcome and Process Assessment (Health Care); Primary Health Care; Brazil
5.  Gestational diabetes mellitus (GDM) decreases butyrylcholinesterase (BChE) activity and changes its relationship with lipids 
Many conditions interfere with butyrylcholinesterase (BChE) activity, e.g., pregnancy or presence of the BCHE gene variant −116A can decrease activity whereas obesity and types I and II diabetes mellitus can increase activity. In this study, we examined BChE activity, −116A and 1615A BCHE gene variants, and anthropometric and biochemical variables associated with diabetes in patients with gestational diabetes mellitus (GDM) and in healthy pregnant women. BChE activity was measured spectrophotometrically using propionylthiocholine as substrate and genotyping of the −116 and 1615 sites of the BCHE gene was done with a TaqMan SNP genotyping assay. Three groups were studied: 150 patients with GDM, 295 healthy pregnant women and 156 non-pregnant healthy women. Mean BChE activity was significantly lower in healthy pregnant women than in women from the general population and was further reduced in GDM patients. BChE activity was significantly reduced in carriers of −116A in GDM patients and healthy pregnant women. Although GDM patients had a significantly higher mean body mass index (BMI) and triglycerides than healthy pregnant women, they had lower mean BChE activity, suggesting that the lowering effect of GDM on BChE activity was stronger than the characteristic enhancing effect of increased BMI and triglycerides.
PMCID: PMC3958315  PMID: 24688284
butyrylcholinesterase (BChE); gestational diabetes mellitus; −116A variant; 1615A variant
6.  A new device to relieve venipuncture pain can affect haematology test results 
Blood Transfusion  2014;12(Suppl 1):s6-s10.
In vitro diagnostic tests play a key role in patients’ management (e.g., guiding red blood cell transfusions). The aim of this study was to evaluate the impact of an innovative device (Buzzy®) which is claimed to be able to relieve venipuncture pain by means of cold and vibration. This device was applied during collection of venous blood by venipuncture for conventional haematology testing.
Materials and methods
Blood was drawn from 100 volunteers by a single, expert phlebotomist. A vein was located in the left forearm without applying a tourniquet but using a subcutaneous tissue transilluminator device, so that venous stasis was avoided. Blood samples were collected with a 20G straight needle directly into 4mL K3EDTA vacuum tubes. In sequence, external cold and vibration was established by Buzzy® on the right forearm −5 cm above the venipuncture site- for 1 minute before venipuncture and continued until the end of the same procedure already performed in the left forearm. Conventional haematological tests were performed using the same instrument (Sysmex® XE-2100D) in all cases.
When Buzzy® was applied before drawing blood, erythrocyte counts and associated parameters (i.e., haemoglobin and haematocrit) were higher, whereas platelet number, leucocyte count and differential were lower. Statistically and clinically significant differences (P <0.001) were observed for erythrocytes, haemoglobin and haematocrit.
From a practical perspective, cold-induced haemoconcentration promotes the efflux of water, diffusible ions and low molecular weight molecules from the vessel, thus increasing the concentration of other blood analytes at the puncture site. These variations may influence test results, especially for erythrocytes, haemoglobin and haematocrit. The novel Buzzy® device should, therefore, be used with caution when collecting blood for conventional haematological testing because of the observed bias introduced in some parameters.
PMCID: PMC3934256  PMID: 24120583
blood specimen collection; laboratory error; phlebotomy; preanalytical variability; reproducibility of results
7.  The effective reduction of tourniquet application time after minor modification of the CLSI H03-A6 blood collection procedure 
Biochemia Medica  2013;23(3):308-315.
The phlebotomists’ procedures are a still source of laboratory variability. The aim of this study was to verify the efficacy of minor modification in procedure for collection of diagnostic blood specimens by venipuncture from CLSI H03-A6 document is able to reduce the tourniquet application time.
Materials and methods:
Thirty phlebotomists were invited to participate. Each phlebotomist was trained individually to perform the new venipuncture procedure that shortens the time of tourniquet release and removal. The phlebotomy training program was delivered over 8h. After training, all phlebotomists were monitored for 20 working days, to guarantee the adoption of the correct new procedures for collection of diagnostic blood specimens. After this time frame the phlebotomists were evaluated to verify whether the new procedure for blood collection derived from CLSI H03-A6 document was effective to improve the quality process by decrease in tourniquet application time. We compared the tourniquet application time and qualitative difference of phlebotomy procedures between laboratories before and after phlebotomy training.
The overall mean ± SD tourniquet application time before and after this intervention were 118 ± 1 s and 30 ± 1 s respectively. Minor modifications in procedure for blood collection were able to reduce significantly the tourniquet application time (−88 s, P < 0.001).
The minor modifications in procedure for collection of diagnostic blood specimens by venipuncture from CLSI H03-A6 document were able to reduce the tourniquet application time. Now the proposed new procedure for collection of diagnostic blood specimens by venipuncture could be considered usefulness and should be put into practice by all quality laboratory managers and/or phlebotomy coordinators to avoid preanalytical errors regard venous stasis and guarantee patient safety.
PMCID: PMC3900072  PMID: 24266300
venous stasis; preanalytical phase; tourniquets; phlebotomy; practice guidelines
8.  Incorrect order of draw could be mitigate the patient safety: a phlebotomy management case report 
Biochemia Medica  2013;23(2):218-223.
Procedures involving phlebotomy are critical for obtaining diagnostic blood specimens and represent a well known and recognized problem, probably among the most important issues in laboratory medicine. The aim of this report is to show spurious hyperkalemia and hypocalcemia due to inadequate phlebotomy procedure. The diagnostic blood specimens were collected from a male outpatient 45 years old, with no clinical complaints. The tubes drawing order were as follows: i) clot activator and gel separator (serum vacuum tube), ii) K3EDTA, iii) a needleless blood gas dedicated-syringe with 80 I.U. lithium heparin, directly connected to the vacuum tube holder system. The laboratory testing results from serum vacuum tube and dedicated syringe were 4.8 and 8.5 mmol/L for potassium, 2.36 and 1.48 mmol/L for total calcium, respectively. Moreover 0.15 mmol/L of free calcium was observed in dedicated syringe. A new blood collection was performed without K3EDTA tube. Different results were found for potassium (4.7 and 4.5 mmol/L) and total calcium (2.37 and 2.38 mmol/L) from serum vacuum tube and dedicated syringe, respectively. Also free calcium showed different concentration (1.21 mmol/L) in this new sample when compared with the first blood specimen. Based on this case we do not encourage the laboratory managers training the phlebotomists to insert the dedicated syringes in needle-holder system at the end of all vacuum tubes. To avoid double vein puncture the dedicated syringe for free calcium determination should be inserted immediately after serum tubes before EDTA vacuum tubes.
PMCID: PMC3900060  PMID: 23894868
clinical laboratory techniques; preanalytical phase; laboratory variability; blood specimen collection; EDTA contamination carryover
9.  Impact of the phlebotomy training based on CLSI/NCCLS H03-A6 - procedures for the collection of diagnostic blood specimens by venipuncture. 
Biochemia Medica  2012;22(3):342-351.
The activities involving phlebotomy, a critical task for obtaining diagnostic blood samples, are poorly studied as regards the major sources of errors and the procedures related to laboratory quality control. The aim of this study was to verify the compliance with CLSI documents of clinical laboratories from South America and to assess whether teaching phlebotomists to follow the exact procedure for blood collection by venipuncture from CLSI/NCCLS H03-A6 - Procedures for the Collection of Diagnostic Blood Specimens by Venipuncture might improve the quality of the process.
Materials and methods:
A survey was sent by mail to 3674 laboratories from South America to verify the use of CLSI documents. Thirty skilled phlebotomists were trained with the CLSI H03-A6 document to perform venipuncture procedures for a period of 20 consecutive working days. The overall performances of the phlebotomists were further compared before and after the training program.
2622 from 2781 laboratories that did answer our survey used CLSI documents to standardize their procedures and process. The phlebotomists’ training for 20 days before our evaluation completely eliminated non-conformity procedures for: i) incorrect friction of the forearm, during the cleaning of the venipuncture site to ease vein location; ii) incorrect sequence of vacuum tubes collection; and iii) inadequate mixing of the blood in primary vacuum tubes containing anticoagulants or clot activators. Unfortunately the CLSI H03-A6 document does not caution against both unsuitable tourniquet application time (i.e., for more than one minute) and inappropriate request to clench the fist repeatedly. These inadequate procedures were observed for all phlebotomists.
We showed that strict observance of the CLSI H03-A6 document can remarkably improve quality, although the various steps for collecting diagnostic blood specimens are not a gold standard, since they may still permit errors. Tourniquet application time and forearm clench should be verified by all quality laboratory managers in the services. Moreover, the procedure for collecting blood specimens should be revised to eliminate this source of laboratory variability and safeguard the quality.
PMCID: PMC3900046  PMID: 23092065
phlebotomy; blood specimen collection; tourniquet application time; CLSI documents; pre-analytic variability; extra- analytical variability
10.  K3EDTA Vacuum Tubes Validation for Routine Hematological Testing 
ISRN Hematology  2012;2012:875357.
Background and Objective. Some in vitro diagnostic devices (e.g, blood collection vacuum tubes and syringes for blood analyses) are not validated before the quality laboratory managers decide to start using or to change the brand. Frequently, the laboratory or hospital managers select the vacuum tubes for blood collection based on cost considerations or on relevance of a brand. The aim of this study was to validate two dry K3EDTA vacuum tubes of different brands for routine hematological testing. Methods. Blood specimens from 100 volunteers in two different K3EDTA vacuum tubes were collected by a single, expert phlebotomist. The routine hematological testing was done on Advia 2120i hematology system. 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 < 0.05. Results and Conclusions. Different brand's tubes evaluated can represent a clinically relevant source of variations only on mean platelet volume (MPV) and platelet distribution width (PDW). Basically, our validation will permit the laboratory or hospital managers to select the brand's vacuum tubes validated according to him/her technical or economical reasons for routine hematological tests.
PMCID: PMC3409519  PMID: 22888448
11.  Influence of a Regular, Standardized Meal on Clinical Chemistry Analytes 
Annals of Laboratory Medicine  2012;32(4):250-256.
Preanalytical variability, including biological variability and patient preparation, is an important source of variability in laboratory testing. In this study, we assessed whether a regular light meal might bias the results of routine clinical chemistry testing.
We studied 17 healthy volunteers who consumed light meals containing a standardized amount of carbohydrates, proteins, and lipids. We collected blood for routine clinical chemistry tests before the meal and 1, 2, and 4 hr thereafter.
One hour after the meal, triglycerides (TG), albumin (ALB), uric acid (UA), phosphatase (ALP), Ca, Fe, and Na levels significantly increased, whereas blood urea nitrogen (BUN) and P levels decreased. TG, ALB, Ca, Na, P, and total protein (TP) levels varied significantly. Two hours after the meal, TG, ALB, Ca, Fe, and Na levels remained significantly high, whereas BUN, P, UA, and total bilirubin (BT) levels decreased. Clinically significant variations were recorded for TG, ALB, ALT, Ca, Fe, Na, P, BT, and direct bilirubin (BD) levels. Four hours after the meal, TG, ALB, Ca, Fe, Na, lactate dehydrogenase (LDH), P, Mg, and K levels significantly increased, whereas UA and BT levels decreased. Clinically significant variations were observed for TG, ALB, ALT, Ca, Na, Mg, K, C-reactive protein (CRP), AST, UA, and BT levels.
A significant variation in the clinical chemistry parameters after a regular meal shows that fasting time needs to be carefully considered when performing tests to prevent spurious results and reduce laboratory errors, especially in an emergency setting.
PMCID: PMC3384805  PMID: 22779065
Blood specimen collection; Clinical laboratory techniques; Diagnostic errors; Eating; Fasting; Postprandial period; Reference values; Reproducibility of results; Quality control; Specimen handling
12.  Preanalytical management: serum vacuum tubes validation for routine clinical chemistry 
Biochemia Medica  2012;22(2):180-186.
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 diff erent 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 diff erences 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.
PMCID: PMC4062344  PMID: 22838184
preanalytical variability; blood collection; serum samples; vacuum tubes; validation process
13.  Influence of a light meal on routine haematological tests 
Blood Transfusion  2010;8(2):94-99.
Patient-related variables, such as physical exercise, stress and fasting status are important sources of variability in laboratory testing. However, no clear indications about fasting requirements exist for routine haematological tests, nor has the influence of meals been assessed.
We studied 17 healthy volunteers who consumed a light meal containing a standardized amount of carbohydrates, protein and lipids. Blood was taken for routine haematological tests before the meal and 1, 2 and 4 hours thereafter.
One hour after the meal, neutrophil count and mean corpuscular haemoglobin (MHC) increased significantly, whereas lymphocyte and monocyte counts, red blood cell distribution width, haematocrit, and mean corpuscular volume decreased significantly. A clinically significant variation was only observed for lymphocytes. Two hours after the meal, a significant increase was observed for neutrophils and MCH, whereas lymphocytes, eosinophils, haemoglobin and haematocrit decreased significantly. Clinically significant variations were recorded for lymphocytes, red blood cells (RBC), haemoglobin, haematocrit and MCH. Four hours after the meal MCH was significantly increased, while lymphocytes, eosinophils, RBC, haemoglobin and haematocrit were significantly decreased. Clinically significant variations were recorded for neutrophils, eosinophils, RBC, hematocrit and MCH.
The significant variation of several haematological parameters after a light meal demonstrates that the fasting time needs to be carefully considered in order to interpret the results of haematological tests correctly.
PMCID: PMC2851212  PMID: 20383302
fasting; haematological tests; meal; pre-analytical variability

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