首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 527 毫秒
1.

Background:

In vitro hemolysis can be induced by several biological and technical sources, and may be worsened by forced aspiration of blood in vacuum tubes. This study was aimed to compare the probability of hemolysis by drawing blood with a commercial evacuated blood collection tube, and S-Monovette used either in the “vacuum” or “aspiration” mode.

Materials and methods:

The study population consisted in 20 healthy volunteers. A sample was drawn into 4.0 mL BD Vacutainer serum tube from a vein of one upper arm. Two other samples were drawn with a second venipuncture from a vein of the opposite arm, into 4.0 mL S-Monovette serum tubes, by both vacuum an aspiration modes. After separation, serum potassium, lactate dehydrogenase (LD) and hemolysis index (HI) were tested on Beckman Coulter DxC.

Results:

In no case the HI exceed the limit of significant hemolysis. As compared with BD Vacutainer, no significant differences were observed for potassium and LD using S-Monovette with vacuum method. Significant increased values of both parameters were however found in serum collected into BD Vacutainer and S-Monovette by vacuum mode, compared to serum drawn by S-Monovette in aspiration mode. The mean potassium bias was 2.2% versus BD Vacutainer and 2.4% versus S-Monovette in vacuum mode, that of LD was 2.7% versus BD Vacutainer and 2.1% versus S-Monovette in vacuum mode. None of these variations exceeded the allowable total error.

Conclusions:

Although no significant macro-hemolysis was observed with any collection system, the less chance of producing micro-hemolysis by S-Monovette in aspiration mode suggest that this device may be used when a difficult venipuncture combined with the vacuum may increase the probability of spurious hemolysis.  相似文献   

2.

Introduction:

Blood collection through intravenous lines frequently causes spurious hemolysis. Due to specific structure, the tube holder Holdex® (Greiner Bio-One GmbH, Kremsmuenster, Austria) is supposed to prevent erythrocyte injury in samples collected from catheters, so that we planned a specific study to support this hypothesis.

Materials and methods:

Blood was collected from emergency department (ED) patients with 20-gauge catheter. In patients with odd order numbers, first and second tubes were collected with conventional holder (BD Vacutainer One Use Holder, Becton Dickinson, Milan, Italy) and the third with Holdex, whereas in even patients first and second tubes were drawn with Holdex and the third using BD Vacutainer One Use Holder. The first tube was discarded, whereas the second and third were centrifuged and serum was tested for potassium, lactate dehydrogenase (LD) and hemolysis index.

Results:

The final study population consisted in 60 ED patients. Concentrations of potassium (4.25 vs. 4.16 mmol/L; P = 0.031), LD (498 vs. 459 U/L; P = 0.039) and cell-free hemoglobin (0.42 vs. 0.22 g/L; P = 0.042) were higher in samples collected with BD Vacutainer One Use Holder than with Holdex. The mean bias of cell-free hemoglobin was −0.4 g/L in samples collected with Holdex. Although the frequency of samples with cell-free hemoglobin > 0.5 g/L was identical (17/60 vs. 17/60; P = 1.00), the frequency of those with concentrations >3.0 g/L was higher using BD Vacutainer One Use Holder than Holdex (4/60 vs. 0/60; P = 0.042).

Conclusions:

The use of Holdex for drawing blood from intravenous lines may be effective for reducing gross hemolysis.  相似文献   

3.

Background:

A number of preanalytical activities strongly influence sample quality, especially those related to sample collection. Since blood drawing through intravenous catheters is reported as a potential source of erythrocyte injury, we performed a critical review and meta-analysis about the risk of catheter-related hemolysis.

Materials and methods:

We performed a systematic search on PubMed, Web of Science and Scopus to estimate the risk of spurious hemolysis in blood samples collected from intravenous catheters. A meta-analysis with calculation of Odds ratio (OR) and Relative risk (RR) along with 95% Confidence interval (95% CI) was carried out using random effect mode.

Results:

Fifteen articles including 17 studies were finally selected. The total number of patients was 14,796 in 13 studies assessing catheter and evacuated tubes versus straight needle and evacuated tubes, and 1251 in 4 studies assessing catheter and evacuated tubes versus catheter and manual aspiration. A significant risk of hemolysis was found in studies assessing catheter and evacuated tubes versus straight needle and evacuated tubes (random effect OR 3.4; 95% CI = 2.9–3.9 and random effect RR 1.07; 95% CI = 1.06–1.08), as well as in studies assessing catheter and evacuated tubes versus catheter and manual aspiration of blood (OR 3.7; 95% CI = 2.7–5.1 and RR 1.32; 95% CI = 1.24–1.40).

Conclusions:

Sample collection through intravenous catheters is associated with significant higher risk of spurious hemolysis as compared with standard blood drawn by straight needle, and this risk is further amplified when intravenous catheter are associated with primary evacuated blood tubes as compared with manual aspiration.  相似文献   

4.

Introduction:

Serum blood collection tubes with separator gel are widely used by many laboratories for chemistry analyses. We describe a case of a primary blood collection tube filled with blood sample and a floating separator gel.

Materials and methods:

The blood sample was collected from a 51 years old female in intensive care unit with the diagnosis of pneumonia into a BD Vacutainer SST tube (Becton Dickinson, NJ, USA) containing serum separator gel and conveyed to the core laboratory of Marmara University Hospital within 30 minutes from collection. Sample was immediately centrifuged at room temperature at 1500 × g for 10 minutes.

Results:

The analyses revealed a highly increased total protein concentration of 145 g/L (reference interval 64–83 g/L). The nephelometric analyses showed an elevated serum IgG concentration of 108 g/L (reference interval 6.5–16 g/L) and IgG lambda monoclonal band was determined by serum immunofixation electrophoresis.

Conclusion:

Limitation of the separator gel tubes in patients with a high plasma density and its possible effects on test results and laboratory costs should be remembered. The clinical diagnosis stated in the information system should also reveal known comorbid conditions besides the apparent admission reason. This information would avoid resampling, additional testing, and communication efforts with the clinicians.  相似文献   

5.

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.  相似文献   

6.

Introduction:

Preanalytical variables account for most of laboratory errors. There is a wide range of factors that affect the reliability of laboratory report. Most convenient sample type for routine laboratory analysis is serum. BD Vacutainer® Rapid Serum Tube (RST) (Becton, Dickinson and Company, Franklin Lakes, NJ, USA) blood collection tube provides rapid clotting time allowing fast serum separation. Our aim was to evaluate the comparability of routine chemistry parameters in BD Vacutainer® RST blood collection tube in reference with the BD Vacutainer® Serum Separating Tubes II Advance Tube (SST) (Becton, Dickinson and Company, Franklin Lakes, NJ, USA).

Materials and methods:

Blood specimens were collected from 90 participants for evaluation on its results, clotting time and stability study of six routine biochemistry parameters: glucose (Glu), aspartate aminotransferase (AST), alanine aminotransferase (ALT), calcium (Ca), lactate dehidrogenase (LD) and potassium (K) measured with Olympus AU2700 analyzer (Beckman Coulter, Tokyo, Japan). The significance of the differences between samples was assessed by paired t-test or Wilcoxon Matched-Pairs Rank test after checking for normality.

Results:

Clotting process was significantly shorter in the RSTs compared to SSTs (2.49 min vs. 19.47 min, respectively; P < 0.001). There was a statistically significant difference between the RST and SST II tubes for glucose, calcium and LD (P < 0.001). Differences for glucose and LD were also clinically significant. Analyte stability studies showed that all analytes were stable for 24 h at 4 °C.

Conclusions:

Most results (except LD and glucose) from RST are comparable with those from SST. In addition, RST tube provides shorter clotting time.  相似文献   

7.

Introduction:

Sample type recommended by the manufacturer for the digoxin Abbott assay is either serum collected in glass tubes or plasma (sodium heparin, lithium heparin, citrate, EDTA or oxalate as anticoagulant) collected in plastic tubes. In our hospital samples are collected in plastic tubes. Our hypothesis was that the serum sample collected in plastic serum tube can be used interchangeably with plasma sample for measurement of digoxin concentration. Our aim was verification of plastic serum tubes for determination of digoxin concentration.

Materials and methods:

Concentration of digoxin was determined simultaneously in 26 venous blood plasma (plastic Vacuette, LH Lithium heparin) and serum (plastic Vacuette, Z Serum Clot activator; both Greiner Bio-One GmbH, Kremsmünster, Austria) samples, on Abbott AxSYM analyzer using the original Abbott Digoxin III assay (Abbott, Wiesbaden, Germany). Tube comparability was assessed using the Passing Bablok regression and Bland-Altman plot.

Results:

Serum and plasma digoxin concentrations are comparable. Passing Bablok intercept (0.08 [95% CI = −0.10 to 0.20]) and slope (0.99 [95% CI = 0.92 to 1.11]) showed there is no constant or proportional error.

Conclusion:

Blood samples drawn in plastic serum tubes and plastic plasma tubes can be interchangeably used for determination of digoxin concentration.  相似文献   

8.

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 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.  相似文献   

9.

Introduction

The collected and shipped blood samples are exposed to a various extra-analytical factors prior to analysis. The aim of the study was to determine the stability of analytes in serum gel tubes and plain tubes exposed to a range of storage temperatures and times after centrifugation.

Materials and methods:

Fifteen healthy volunteers were recruited and venous blood was collected into four tubes, two with and two without gel separator. Analyzing the baseline samples in 30 min, all were stored at 4ºC or 24ºC for 6, 12, 18, 24, 30, 36, 48 and 72 hours and 1 week. Sixteen biochemical anaytes were measured on each sample. Variations remained under the desirable bias considered as clinically insignificant.

Results:

On day three, most analytes remained stable including albumin, protein, creatinine, cholesterol, triglycerides, gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), alanine aminotransferase (ALT), creatine kinase (CK), lactate dehydrogenase (LD) regardless of tube types. Glucose concentration decreased markedly (P = 0.001) beginning from the first hours of storage in plain serum. The stability maximized for the analytes including glucose, total bilirubin, urea nitrogen (BUN), uric acid stored at 4 ºC in gel tubes. Aspartate aminotransferase (AST) activity increased significantly (P = 0.002) up to 48-h, however bias was not significant clinically. High density lipoprotein (HDL) concentration was stable in gel tubes at 24 ºC, in plain tubes at 4 ºC stored up to 36-h.

Conclusion:

Serum gel or non-gel tubes might be used interchangeably for 11 analytes chilled or at 24 ºC, whereas some restrictions must be applied for glucose, AST, BUN, HDL, and uric acid.  相似文献   

10.

Introduction:

Preanalytical errors, along the process from the beginning of test requests to the admissions of the specimens to the laboratory, cause the rejection of samples. The aim of this study was to better explain the reasons of rejected samples, regarding to their rates in certain test groups in our laboratory.

Materials and methods:

This preliminary study was designed on the rejected samples in one-year period, based on the rates and types of inappropriateness. Test requests and blood samples of clinical chemistry, immunoassay, hematology, glycated hemoglobin, coagulation and erythrocyte sedimentation rate test units were evaluated. Types of inappropriateness were evaluated as follows: improperly labelled samples, hemolysed, clotted specimen, insufficient volume of specimen and total request errors.

Results:

A total of 5,183,582 test requests from 1,035,743 blood collection tubes were considered. The total rejection rate was 0.65 %. The rejection rate of coagulation group was significantly higher (2.28%) than the other test groups (P < 0.001) including insufficient volume of specimen error rate as 1.38%. Rejection rates of hemolysis, clotted specimen and insufficient volume of sample error were found to be 8%, 24% and 34%, respectively. Total request errors, particularly, for unintelligible requests were 32% of the total for inpatients.

Conclusions:

The errors were especially attributable to unintelligible requests of inappropriate test requests, improperly labelled samples for inpatients and blood drawing errors especially due to insufficient volume of specimens in a coagulation test group. Further studies should be performed after corrective and preventive actions to detect a possible decrease in rejecting samples.  相似文献   

11.

Introduction

This study aimed to assess confidence level of healthcare professionals in venipuncture and their knowledge on the possible causes of in vitro hemolysis.

Materials and methods

A sample of 94 healthcare professionals (nurses and laboratory technicians) participated in this survey study. A four-section questionnaire was used as a research instrument comprising general information for research participants, knowledge on possible causes of in vitro hemolysis due to type of material used and venipuncture technique and specimen handling, as well as assessment of healthcare professionals’ confidence level in their own ability to perform first and last venipuncture.

Results

The average score on the knowledge test was higher in nurses’ than in laboratory technicians (8.11 ± 1.7, and 7.4 ± 1.5, respectively). The difference in average scores was statistically significant (P = 0.035) and Cohen’s d in the range of 0.4 indicates that there is a moderate difference on the knowledge test among the health care workers. Only 11/94 of healthcare professionals recognized that blood sample collection from cannula and evacuated tube is method which contributes most to the occurrence of in vitro hemolysis, whereas most risk factors affecting occurrence of in vitro hemolysis during venipuncture were recognized. There were no significant differences in mean score on the knowledge test in relation to the confidence level in venipuncture (P = 0.551).

Conclusion

Confidence level at last venipuncture among both profiles of healthcare staff was very high, but they showed insufficient knowledge about possible factors affecting hemolysis due to materials used in venipuncture compared with factors due to venipuncture technique and handling of blood sample.Key words: hemolysis, patient safety, phlebotomy, medical staff, questionnaire, preanalytical phase  相似文献   

12.

Background

Platelet satellitism is a phenomenon of unknown etiology of aggregating platelets around polymorphonuclear neutrophils and other blood cells which causes pseudothrombocytopenia, visible by microscopic examination of blood smears. It has been observed so far in about a hundred cases in the world.

Case subject and methods

Our case involves a 73-year-old female patient with a urinary infection. Biochemical serum analysis (CRP, glucose, AST, ALT, ALP, GGT, bilirubin, sodium, potassium, chloride, urea, creatinine) and blood cell count were performed with standard methods on autoanalyzers. Serum protein fractions were examined by electrophoresis and urinalysis with standard methods on autoanalyzer together with microscopic examination of urine sediment. Erythrocyte sedimentation rate, blood culture and urine culture tests were performed with standard methods.

Results

Due to typical pathological values for bacterial urinary infection, the patient was admitted to the hospital. Blood smear examination revealed phenomenon, which has persisted for three weeks after the disease has been cured. Blood smears with EDTA as an anticoagulant had platelet satellitism whereas the phenomenon was not observed in tubes with different anticoagulants (Na, Li-heparin) and capillary blood.

Discussion

We hypothesize that satellitism was induced by some immunological mechanism through formation of antibodies which have mediated platelets binding to neutrophil membranes and vice versa. Unfortunately we were unable to determine the putative trigger for this phenomenon. To our knowledge this is the second case of platelet satellitism ever described in Croatia.Key words: blood platelets, thrombocytopenia, EDTA, urinary infection  相似文献   

13.

Introduction

The emergency laboratory in Hacettepe University Hospitals receives specimens from emergency departments (EDs), inpatient services and intensive care units (ICUs). The samples are accepted according to the rejection criteria of the laboratory. In this study, we aimed to evaluate the sample rejection ratios according to the types of pre-preanalytical errors and collection areas.

Materials and methods

The samples sent to the emergency laboratory were recorded during 12 months between January to December, 2013 in which 453,171 samples were received and 27,067 specimens were rejected.

Results

Rejection ratios was 2.5% for biochemistry tests, 3.2% for complete blood count (CBC), 9.8% for blood gases, 9.2% for urine analysis, 13.3% for coagulation tests, 12.8% for therapeutic drug monitoring, 3.5% for cardiac markers and 12% for hormone tests. The most frequent rejection reasons were fibrin clots (28%) and inadequate volume (9%) for biochemical tests. Clotted samples (35%) and inadequate volume (13%) were the major causes for coagulation tests, blood gas analyses and CBC. The ratio of rejected specimens was higher in the EDs (40%) compared to ICUs (30%) and inpatient services (28%). The highest rejection ratio was observed in neurology ICU (14%) among the ICUs and internal medicine inpatient service (10%) within inpatient clinics.

Conclusions

We detected an overall specimen rejection rate of 6% in emergency laboratory. By documentation of rejected samples and periodic training of healthcare personnel, we expect to decrease sample rejection ratios below 2%, improve total quality management of the emergency laboratory and promote patient safety.Key words: clinical laboratory services, total quality management, patient safety, preanalytical phase, preanalytical error  相似文献   

14.

Introduction

The determination of lipid biomarkers by capillary sampling may be useful in the screening, diagnosis and/or personal management of hyperlipidemia and cardiovascular risk. It remains unclear whether the use of the Accutrend® Plus system is appropriate. This study aimed to assess its reproducibility, accuracy and concordance for blood lipid profiling in adults.

Materials and methods:

Fasting capillary total cholesterol (TC) and triglyceride (TG) concentration on Accutrend® Plus were compared with their venous analogues obtained by a laboratory reference method in sixty-one adults (27 men and 34 women, aged 33.0 years). Supplementary capillary sampling was performed at two consecutive days taking into account macro-nutrient intake.

Results:

The day-to-day reproducibility of the Accutrend® Plus system proved to be high for TC (ICC = 0.85, P < 0.001), but moderate for TG (ICC = 0.68, P < 0.001). Strong correlations (r ≥ 0.80, P < 0.001) with the reference method were found for TC and TG. Mean difference (limits of agreement) were: 0.26 mmol/L (−0.95, 1.47) for TC, and −0.16 mmol/L (−1.29, 0.98) for TG. The concordance for subject classification according to the National Cholesterol Education Program (NCEP) guidelines was significant (P < 0.001), with substantial agreement for TC (κw = 0.67), and moderate agreement for TG (κw = 0.50).

Conclusions:

Day-to-day reproducibility of the Accutrend® Plus device for TC and TG is not optimal and lacks accuracy when compared to the reference laboratory method. The concordance between both methods for classifying subjects according to the NCEP is inadequate. Accutrend® Plus device should not be interchangeably used as a substitution for the standard laboratory methods in the diagnosis of hyperlipidemia.  相似文献   

15.

Introduction

Glycolysis affects glucose determination in vitro. The placement of sample tubes in ice-water slurry with plasma separation within 30 minutes is recommended, or alternatively the use of a glycolysis inhibitor. The aim of our two-steps study was to evaluate which Terumo tube is best for glucose determination in routine clinical setting.

Materials and methods

In the first study, blood from 100 volunteers was collected into lithium heparin (LH), NaF/Na heparin (FH) and NaF/citrate buffer/Na2EDTA (FC-Mixture) tubes. LH sample was treated as recommended and considered as reference, while FH and FC-Mixture samples were aliquoted, maintained at room temperature (RT) for 1, 2 and 4 hours; centrifuged and plasma analysed in triplicate. In the second study, samples from 375 volunteers were collected in LH, FH and FC-Mixture tubes and held at RT before centrifugation from 10 to 340 minutes, depending on each laboratory practice. Samples were analysed in one analytical run.

Results

In the first study, FH glucose concentrations were 5.15 ± 0.66 mmol/L, 5.05 ± 0.65 mmol/L and 5.00 ± 0.65 mmol/L (P < 0.001) in tubes stored at RT for 1, 2 and 4 hours, respectively. Mean biases in all time points exceeded the analytical goal for desirable bias based on biological variation criteria. FC-Mixture glucose concentrations were 5.48 ± 0.65 mmol/L, 5.46 ± 0.6 mmol/L and 5.46 ± 0.64 mmol/L in tubes stored at RT for 1, 2 and 4 hours, respectively. Mean biases for FC-Mixture glucose in all time points reached optimal analytical goals. In the second study, the biases for LH and FH glucose compared to reference FC-Mixture glucose exceeded the preset analytical goals, regardless of the blood collection to centrifugation time interval.

Conclusions

FC-mixture tubes glucose concentrations were preserved up to 4h storage at RT. We confirmed that NaF alone does not allow immediate glycolysis inhibition in real life pre-centrifugation storage conditions (up to 340 minutes). FC-Mixture should be used exclusively for glucose determination in laboratories unable to implement the recommended blood samples’ treatment.Key words: glucose, pre-analytical phase, sodium fluoride, citrate acidification, stability  相似文献   

16.

Introduction

Hemolysis can occur during sample collection, handling and transport. It is more frequent when the non-laboratory staff performs sampling. The aim of this study was to assess nurses’ knowledge on the causes of hemolysis and consequential impact on the laboratory tests results. Additionally, the differences in knowledge, related to work experience, professional degree and previous education about hemolysis were explored.

Materials and methods

An anonymus survey, containing 11 questions on demographics, causes of hemolysis, its impact on biochemical parameters and nurses’ attitude towards additional education in preanalytics, was conducted in four Croatian hospitals. The answers were compared by Chi-squared and Fischer exact test.

Results

In total, 562 survey results were collected. Majority of nurses declared familiarity with the term “hemolysis” (99.6%). There were 77% of correct answers regarding questions about the causes of hemolysis, but only 50% when it comes to questions about interference in biochemical tests. The percentage of correct answers about causes was significantly lower (P = 0.029) among more experienced nurses, and higher (P = 0.027) in those with higher professional degree, while influence of previous education was not significant. Also, higher percentage of correct answers about interferences was encountered in nurses with longer work experience (P = 0.039). More than 70% of nurses declared that additional education about preanalytical factors would be beneficial.

Conclusion

Croatian nurses are familiar with the definition of hemolysis, but a lack of knowledge about causes and influence on laboratory test results is evident. Nurses are eager to improve their knowledge in this field of preanalytical phase.Key words: hemolysis, nurses, survey, preanalytical phase  相似文献   

17.

Background

In heart failure patients, mean platelet volume (MPV) may reflect increased platelet activation or increased numbers of large, hyper-aggregable platelets. B-type natriuretic peptide (BNP) concentration in blood is a sensitive and specific marker of heart failure, correlating with the severity and prognosis of illness, in patients presenting with acute dyspnea to the emergency department. This study evaluated the correlation between BNP concentration and MPV.

Material and methods

Data were collected from 319 patients admitted to the emergency department of a cardiology hospital from January–July 2014. EDTA blood samples drawn at admission were analyzed using automated hematology system, and BNP concentration was measured using a fluorescence immunoassay.

Results

The study included 190 patients with and 129 without acute heart failure (AHF). These groups had BNP concentration of 200-5000 ng/L and 5-98 ng/L, respectively. MPV levels were significantly higher in the AHF group (P < 0.001). BNP concentrations were positively correlated with MPV (r = 0.41, P < 0.001) and neutrophil / lymphocyte ratio (r = 0.38, P < 0.001).

Conclusion

Increased MPV values correlate with BNP concentration, an indicator of HF severity and clinical status, in patients with AHF admitted to the emergency department.Key words: natriuretic peptide, brain; heart failure; platelet; mean platelet volume  相似文献   

18.

Introduction

The educational program for health care personnel is important for reducing preanalytical errors and improving quality of laboratory test results. The aim of our study was to assess the level of knowledge on preanalytical phase in population of biomedicine students through a cross-sectional survey.

Materials and methods

A survey was sent to students on penultimate and final year of Faculty of Pharmacy and Biochemistry – study of medical biochemistry (FPB), Faculty of Veterinary Medicine (FVM) and School of Medicine (SM), University of Zagreb, Croatia, using the web tool SurveyMonkey. Survey was composed of demographics and 14 statements regarding the preanalytical phase of laboratory testing. Comparison of frequencies and proportions of correct answers was done with Fisher’s exact test and test of comparison of proportions, respectively.

Results

Study included 135 participants, median age 24 (23-40) years. Students from FPB had higher proportion of correct answers (86%) compared to students from other biomedical faculties 62%, P < 0.001. Students from FPB were more conscious of the importance of specimen mixing (P = 0.027), prevalence of preanalytical errors (P = 0.001), impact of hemolysis (P = 0.032) and lipemia interferences (P = 0.010), proper choice of anticoagulants (P = 0.001), transport conditions for ammonia sample (P < 0.001) and order of draw during blood specimen collection (P < 0.001), in comparison with students from SM and FVM.

Conclusions

Students from FPB are more conscious of the importance of preanalytical phase of testing in comparison with their colleagues from other biomedical faculties. No difference in knowledge between penultimate and final year of the same faculty was found.Key words: survey, education, preanalytical phase  相似文献   

19.

Introduction:

There are a number of pre-analytical and analytical factors, which cause false results in the complete blood count. The present case identifies cold agglutinins as the cause for the mismatch between hematocrit and hemoglobin values.

Materials and methods:

70-year old female patient had a history of cerebrovascular diseases and rheumatoid arthritis. During routine laboratory examination, the patient had normal leukocyte and platelet counts; however, the hemoglobin (Hb: 105 g/L) and hematocrit (HCT: 0.214 L/L) results were discordant. Hemolysis, lipemia and cold agglutinin were evaluated as possible reasons for the mismatch between hematocrit and hemoglobin values.

Results:

First blood sample was slightly hemolysed. Redrawn sample without hemolysis or lipemia was analyzed but the mismatch became even more distinct (Hb: 104 g/L and HCT: 0.08 L/L). In this sample, the titration of the cold agglutinin was determined and found to be positive at 1:64 dilution ratios. After an incubation of the sample at 37°C for 2 hours, reversibility of agglutination was observed.

Conclusion:

We conclude that cold agglutinins may interfere with the analysis of erythrocyte and erythrocyte-related parameters (HCT, MCV, MCH and MCHC); however, Hb, leukocyte and platelet counts are not affected.  相似文献   

20.

Introduction:

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, creatinine and lipase appear overall less vulnerable towards K2EDTA contamination.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号