Drawing coagulation studies from arterial lines: an integrative literature review

1994 ◽  
Vol 3 (1) ◽  
pp. 16-22 ◽  
Author(s):  
CJ Laxson ◽  
MG Titler
Keyword(s):  
Critical Care ◽  
Partial Thromboplastin Time ◽  
Pediatric Patients ◽  
Venous Blood ◽  
Activated Partial Thromboplastin Time ◽  
Arterial Line ◽  
Central Venous ◽  
Blood Samples ◽  
Similarities And Differences ◽  
Insight Into

How much blood must be discarded from a heparinized arterial line to obtain accurate coagulation studies, specifically activated partial thromboplastin time? The published literature provides insight into the question and guidelines for practice in adult critical care. This article reviews and integrates findings from 14 research studies published from 1971 to 1993 on discarding blood from arterial lines for coagulation studies. Investigators compared activated partial thromboplastin time values from arterial and venous blood samples using various discard volumes, sites and sizes of catheters, and heparin flush concentrations. Similarities and differences in arterial and venous activated partial thromboplastin time were reported. Studies have demonstrated that adequate discard volume for activated partial thromboplastin time is 6 times the catheter dead space. These results should not be generalized to systemically heparinized patients, pediatric patients, or other types of heparinized lines such as pulmonary artery, central venous, or Hickman catheters.

Accuracy of drawing coagulation samples from heparinized arterial lines

1993 ◽  
Vol 2 (1) ◽  
pp. 88-95 ◽  
Author(s):  
K Templin ◽  
M Shively ◽  
J Riley
Keyword(s):  
Prothrombin Time ◽  
Partial Thromboplastin Time ◽  
Coronary Angioplasty ◽  
Percutaneous Transluminal Coronary Angioplasty ◽  
Activated Partial Thromboplastin Time ◽  
Arterial Line ◽  
Blood Samples ◽  
Transluminal Coronary Angioplasty ◽  
Percutaneous Transluminal ◽  
Line Sample

OBJECTIVE: To determine the accuracy of activated partial thromboplastin time and prothrombin time studies when samples are drawn through heparinized arterial lines. METHODS: A total sample of 90 grouped blood samples (from 30 subjects) was used. Patients were all male, with a mean age of 65 and were studied within 24 hours of percutaneous transluminal coronary angioplasty. Each patient had three venous control and arterial line sample sets (a total of 90 blood samples) drawn when routinely ordered for monitoring therapy. For the arterial line sample, a discard volume of the deadspace, deadspace + 2 mL, or deadspace + 4 mL was randomly assigned for each sample. The venous control volumes were the same for all three sample sets. RESULTS: A 2 x 3 repeated measures analysis of variance was used to analyze the results. The independent variables were the source of the sample (venous vs arterial) and the discard volume of arterial blood (deadspace, deadspace + 2 mL, deadspace + 4 mL). The dependent variables were the activated partial thromboplastin time and prothrombin time values. Mean arterial activated partial thromboplastin time values were significantly higher than the corresponding venous values. Mean activated partial thromboplastin time values were not significantly different among the discard volumes of blood drawn. However, there was a significant source by volume interaction. Tukey post-hoc comparisons of venous-arterial activated partial thromboplastin time differences among the three volumes showed significant differences between deadspace volume and deadspace + 2 mL, and deadspace volume and deadspace + 4 mL. There was no significant difference between deadspace + 2 mL and deadspace + 4 mL volumes. CONCLUSION: Results indicated that the minimal amount of discard volume for accurate activated partial thromboplastin time values in this population of percutaneous transluminal coronary angioplasty patients was the catheter deadspace volume plus 2 mL (total 3.6 mL).

Comparison of PT and aPTT values drawn by venipuncture and arterial line using three discard volumes

1992 ◽  
Vol 1 (3) ◽  
pp. 94-101 ◽  
Author(s):  
E Konopad ◽  
M Grace ◽  
R Johnston ◽  
T Noseworthy ◽  
A Shustack
Keyword(s):  
Prothrombin Time ◽  
Critically Ill ◽  
Partial Thromboplastin Time ◽  
Laboratory Tests ◽  
Activated Partial Thromboplastin Time ◽  
Arterial Line ◽  
Bonferroni Correction ◽  
Blood Samples ◽  
Volume Group ◽  
Paired T Test

BACKGROUND: Blood samples obtained through heparinized arterial catheters are used routinely for a variety of laboratory tests. Accuracy of coagulation studies performed from samples obtained in this fashion continues to be questioned, particularly in regard to the minimum discard volume necessary to clear the catheter of heparinized solution. OBJECTIVE: To examine differences between prothrombin time and activated partial thromboplastin time values obtained from blood drawn by venipuncture and from an indwelling intra-arterial line using three discard volumes. METHODS: Prothrombin time and activated partial thromboplastin time samples were drawn by venipuncture from 41 critically ill adult patients. Simultaneously, three consecutive blood samples of 2.3 mL were drawn from the arterial line after an initial discard volume of 3 mL (discard volumes of 3.0, 5.3 and 7.6 mL). RESULTS: Significant differences were found between arterial and venous prothrombin time values for the 3-mL discard volume group, as well as between arterial and venous activated partial thromboplastin time values for all three discard volume groups (paired t-test, Bonferroni correction). CONCLUSION: We recommend that when drawing prothrombin time and activated partial thromboplastin time samples from an arterial line, a 5.3-mL discard volume be used.

Coagulopathy Screening in Children With Heparinized Central Venous Catheters

PEDIATRICS ◽  
1993 ◽  
Vol 91 (6) ◽  
pp. 1147-1150
Author(s):  
Robert Ellis
Keyword(s):  
Whole Blood ◽  
Partial Thromboplastin Time ◽  
Central Venous Catheters ◽  
Activated Partial Thromboplastin Time ◽  
Central Venous ◽  
Indwelling Catheter ◽  
Blood Samples ◽  
Paired Samples ◽  
Prolonged Aptt ◽  
Prolonged Test

Objective. To develop a method of screening for coagulopathy using blood drawn through heparinized central venous catheters. Methods. Prothrombin time (PT) and activated partial thromboplastin time (APTT) were determined in paired blood samples with and without the addition of protamine, using an automated photo-optical method. A concentration of 4 µg/mL of citrated whole blood was chosen, based on preliminary experiments. This is sufficient to neutralize the expected heparin contamination in samples drawn through heparinized catheters while causing only a slight prolongation in APTT (due to the anticoagulant effect of protamine). Seventeen paired samples were drawn by venipuncture in patients without known coagulopathy. Twenty-five samples were drawn through heparinized central venous catheters. The first 5 mL of blood drawn from a catheter was discarded to avoid gross heparin contamination. Four samples from patients with coagulopathy were also analyzed with and without the addition of 2.5 µg/mL of heparin. Results. Protamine increased PT by 9.0 ± 0.8% and APTT by 9.0 ± 3.4% (mean ± SD) in the samples drawn by venipuncture. For samples drawn through heparinized catheters, 52% had a prolonged APTT 44% a prolonged PT, and 68% had at least one prolonged test. With the addition of protamine, and after correction for the 9% mean increase in PT and APTT, 4% of samples had a prolonged APTT, 12% had a prolonged PT, and 16% had at least one prolonged test (P = .00006, .014, and .0001). All four samples from patients with coagulopathy were correctly identified as abnormal after the addition of protamine, with or without added heparin. Conclusions. A protamine-supplemented APTT test on blood drawn through a heparinized catheter may be an adequate screening test for coagulopathy. This procedure reduces discomfort in patients with an indwelling catheter by avoiding venipuncture.

Effects of a Pneumatic Tube System on Routine and Novel Hematology and Coagulation Parameters in Healthy Volunteers

2007 ◽  
Vol 131 (2) ◽  
pp. 293-296
Author(s):  
Alexander Kratz ◽  
Raneem O. Salem ◽  
Elizabeth M. Van Cott
Keyword(s):  
Healthy Volunteers ◽  
Prothrombin Time ◽  
Partial Thromboplastin Time ◽  
Activated Partial Thromboplastin Time ◽  
Tube System ◽  
Blood Samples ◽  
Pneumatic Tube ◽  
The Mean ◽  
Clinically Significant ◽  
Pneumatic Tube System

Abstract Context.—Technologic advances affecting analyzers used in clinical laboratories have changed the methods used to obtain many laboratory measurements, and many novel parameters are now available. The effects of specimen transport through a pneumatic tube system on laboratory results obtained with such modern instruments are unclear. Objective.—To determine the effects of sample transport through a pneumatic tube system on routine and novel hematology and coagulation parameters obtained on state-of-the-art analyzers. Design.—Paired blood samples from 33 healthy volunteers were either hand delivered to the clinical laboratory or transported through a pneumatic tube system. Results.—No statistically significant differences were observed for routine complete blood cell count and white cell differential parameters or markers of platelet activation, such as the mean platelet component, or of red cell fragmentation. When 2 donors who reported aspirin intake were excluded from the analysis, there was a statistically, but not clinically, significant impact of transport through the pneumatic tube system on the mean platelet component. There were no statistically significant differences for prothrombin time, activated partial thromboplastin time, waveform slopes for prothrombin time or activated partial thromboplastin time, fibrinogen, or fibrin monomers. Conclusions.—Although further study regarding the mean platelet component may be required, transport through a pneumatic tube system has no clinically significant effect on hematology and coagulation results obtained with certain modern instruments in blood samples from healthy volunteers.

Comparative study of bedside and laboratory measurements of hemoglobin

1996 ◽  
Vol 5 (6) ◽  
pp. 427-432 ◽  
Author(s):  
DA Krenzischek ◽  
FV Tanseco
Keyword(s):  
Venous Blood ◽  
Hemoglobin Level ◽  
Johns Hopkins Hospital ◽  
Postanesthesia Care Unit ◽  
Laboratory Measurements ◽  
Central Venous ◽  
Blood Samples ◽  
Central Venous Blood ◽  
Arterial Blood ◽  
Group I

OBJECTIVE: The purpose of this study was to examine the effects of variations in technique on measurements of hemoglobin level done at the bedside and to compare these results with laboratory measurements of hemoglobin. DESIGN: In accordance with hospital policy, procedure, and protocol, various techniques were used to obtain samples of capillary and venous blood and of blood from arterial and central venous catheters. Levels of hemoglobin were measured at the bedside and in the laboratory, and the results were compared. SETTING: The Johns Hopkins Hospital adult postanesthesia care unit. SAMPLE: A total of 187 blood samples were obtained from 62 adults who had undergone general surgery. Group I comprised 20 subjects with capillary and venous blood samples. Group II comprised 21 subjects with arterial blood samples. Group III comprised 21 subjects with central venous blood samples. RESULTS: The results showed that the amount of blood to be discarded before obtaining samples of arterial and central venous blood need not be any larger than double the dead space of the catheter, and that shaking the blood sample for 10 seconds was sufficient to mix the sample before measurement of hemoglobin levels. Results of bedside and laboratory measurements of hemoglobin level were comparable. CONCLUSION: Bedside measurement of hemoglobin increases efficiency in patient care, decreases risk of blood-transmitted infection for staff, and decreases cost to the patient. However, the persons who perform the assay must be responsible in adhering to the standard of practice to minimize errors in the measurements.

scholarly journals Correlation between Arterial Lactate and Central Venous Lactate in Children with Sepsis

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Jaime Fernández Sarmiento ◽  
Paula Araque ◽  
María Yepes ◽  
Hernando Mulett ◽  
Ximena Tovar ◽  
...  
Keyword(s):  
Septic Shock ◽  
Blood Sample ◽  
Pediatric Patients ◽  
Venous Blood ◽  
Tissue Perfusion ◽  
Central Venous ◽  
Important Indicator ◽  
Arterial Lactate ◽  
Arterial Blood ◽  
Sepsis And Septic Shock

Introduction. Lactate is an important indicator of tissue perfusion. The objective of this study is to evaluate if there are significant differences between the arterial and central venous measurement of lactate in pediatric patients with sepsis and/or septic shock.Methods. Longitudinal retrospective observational study. Forty-two patients were included between the age of 1 month and 17 years, with a diagnosis of sepsis and septic shock, who were admitted to the intensive care unit of a university referral hospital. The lactate value obtained from an arterial blood sample and a central venous blood sample drawn simultaneously, and within 24 hours of admission to the unit, was recorded.Results. The median age was 2.3 years (RIC 0,3–15), with a predominance of males (71.4%), having a 2.5 : 1 ratio to females. Most of the patients had septic shock (78.5%) of pulmonary origin (50.0%), followed by those of gastrointestinal origin (26.1%). Using Spearman’s Rho, a 0.872 (p<0.001) correlation was found between arterial and venous lactate, which did not vary when adjusted for age (p<0.05) and the use of vasoactive drugs (p<0.05).Conclusion. There is a good correlation between arterial and venous lactate in pediatric patients with sepsis and septic shock, which is not affected by demographic variables or type of vasoactive support.

Monitoring Heparin Therapy by the Activated Partial Thromboplastin Time - The Effect of Pre-Analytical Conditions

1987 ◽  
Vol 57 (02) ◽  
pp. 226-231 ◽  
Author(s):  
A M H P van den Besselaar ◽  
J Meeuwisse-Braun ◽  
R Jansen-Grüter ◽  
R M Bertina
Keyword(s):  
Citric Acid ◽  
Partial Thromboplastin Time ◽  
Room Temperature ◽  
Heparin Therapy ◽  
Activated Partial Thromboplastin Time ◽  
Platelet Factor 4 ◽  
Platelet Factor ◽  
Blood Samples ◽  
Hepes Buffer ◽  
Reliable Monitoring

SummaryBlood and plasma specimens from patients receiving heparin were collected and stored under various conditions. The effect of these conditions on the activated partial thromboplastin time (APTT) was assessed. Four APTT reagents were used. Blood samples centrifuged at 600 × g gave slightly shorter APTTs than samples centrifuged at 940 × g and 2200 × g. Storage of uncentrifuged citrated-blood at room temperature resulted in 15-29% shortening of the APTT, depending on the reagent used. Storage of the same blood samples at 4° C resulted in 6-19% lengthening of the APTT. The presence of HEPES-buffer in citrated-blood shortened the APTT of heparinized patient specimens, but not of normal specimens. When blood was collected in a mixture of citric acid, theophylline, adenosine and dipyridamole (CTAD-mix-ture), storage at room temperature induced 0-11% decrease of the APTT, depending on the reagent used. Storage of CTAD-blood at 4° C resulted in 7-19% lengthening of the APTT. Shortening of the APTT could be explained by release of platelet factor 4 (PF4). Release of PF4 could be inhibited by CTAD-mixture. These data suggest that storage of CTAD-blood at room temperature is the best pre-analytical condition for reliable monitoring of heparin therapy by the APTT.

Amniotic Fluid Removal during Cell Salvage in the Cesarean Section Patient

2000 ◽  
Vol 92 (6) ◽  
pp. 1531-1536 ◽  
Author(s):  
Jonathan H Waters ◽  
Charles Biscotti ◽  
Paul S Potter ◽  
Eliot Phillipson
Keyword(s):  
Cesarean Section ◽  
Cell Concentration ◽  
Venous Blood ◽  
Lamellar Body ◽  
Fetal Hemoglobin ◽  
Cell Salvage ◽  
Central Venous ◽  
Blood Samples ◽  
Central Venous Blood ◽  
Leukocyte Depletion

Background Cell salvage has been used in obstetrics to a limited degree because of a fear of amniotic fluid embolism. In this study, cell salvage was combined with blood filtration using a leukocyte depletion filter. A comparison of this washed, filtered product was then made with maternal central venous blood. Methods The squamous cell concentration, lamellar body count, quantitative bacterial colonization, potassium level, and fetal hemoglobin concentration were measured in four sequential blood samples collected from 15 women undergoing elective cesarean section. The blood samples collected included (1) unwashed blood from the surgical field (prewash), (2) washed blood (postwash), (3) washed and filtered blood (postfiltration), and (4) maternal central venous blood drawn from a femoral catheter at the time of placental separation. Results Significant reductions in the following parameters were seen when the postfiltration samples were compared to the prewash samples (median [25th-75th percentile]): squamous cell concentration (0.0 [0.0-0.1 counts/high-powered field (HPF)] vs. 8.3 counts/HPF [4. 0-10.5 counts/HPF], P &lt; 0.05); bacterial contamination (0.1 [0.0-0. 2] vs. 3.0 [0.6-7.7] colony-forming units (CFU)/ml, P &lt; 0.01); and lamellar body concentration (0.0 [0.0-1.0] vs. 22.0 [18.5-29.5] thousands/microl, P &lt; 0.01). No significant differences existed between the postfiltration and maternal samples for each of these parameters. Fetal hemoglobin was in higher concentrations in the postfiltration sample when compared with maternal blood (1.9 [1.1-2. 5] vs. 0.5% [0.3-0.7] ). Potassium levels were significantly less in the postfiltration sample when compared with maternal (1.4 [1.0-1.5] vs. 3.8 mEq/l [3.7-4.0]). Conclusions Leukocyte depletion filtering of cell-salvaged blood obtained from cesarean section significantly reduces particulate contaminants to a concentration equivalent to maternal venous blood.

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