The document discusses pre-analytical errors that can occur prior to laboratory testing and affect test results. It outlines various factors in the pre-analytical phase including proper patient identification, preparation, sample collection techniques, sample handling and processing, and stability of samples. Key areas that can introduce errors are identified as patient identification, order of tube draw, sample mixing and centrifugation, and stability of whole blood, serum and plasma samples. Standardizing procedures and monitoring pre-analytical variables is important for reliable test results and patient outcomes.
Slides on medical laboratory testing process and pre-analytical factors that might contribute to laboratory errors and sample rejection, and how to prevent it.
Preanalytical quality control practices in clinical laboratoryDr. Rajesh Bendre
Preanalytical variables contribute maximally to lab errors. However, these variables are most difficult to control as they include human dependency for phlebotomy skills & pretest patient conditioning. Quantifying & monitoring these variables is also more challenging. Use of checklists, continuous training, competency assessments, internal audits & clinician education for appropriate test utilization form some of the tools for improving the preanalytical processes.
Slides on medical laboratory testing process and pre-analytical factors that might contribute to laboratory errors and sample rejection, and how to prevent it.
Preanalytical quality control practices in clinical laboratoryDr. Rajesh Bendre
Preanalytical variables contribute maximally to lab errors. However, these variables are most difficult to control as they include human dependency for phlebotomy skills & pretest patient conditioning. Quantifying & monitoring these variables is also more challenging. Use of checklists, continuous training, competency assessments, internal audits & clinician education for appropriate test utilization form some of the tools for improving the preanalytical processes.
In the continuous quality journey, Controlling laboratory Errors is an integral part & focusing on analytical, post-analytical process is the first step. Developing a reporting culture followed by thorough analysis and implementation of appropriate corrective, preventive actions is required.
In the continuous quality journey, Controlling laboratory Errors is an integral part & focusing on analytical, post-analytical process is the first step. Developing a reporting culture followed by thorough analysis and implementation of appropriate corrective, preventive actions is required.
Capillary blood collection tubes are essential tools used in healthcare for obtaining small blood samples. we will explore everything you need to know about capillary blood collection tubes. From uses to benefits, this guide will equip you with the knowledge to ensure accurate and efficient blood sample collection.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
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micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
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New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
3. Quality assurance system
“The
activity of a laboratory to ensure the
reliability of test results, to increase accuracy,
reproducibility and laboratory to laboratory
comparability."
Quality assurance system depends upon 3
factors
–
–
–
Pre-analytical factors
Analytical factors
Post-analytical factors
4. Pre-analytical errors
There is consolidated evidence that lack of standardization and
monitoring of pre analytic variables, including procedures for
patient identification, sample collection, handling and
processing has an adverse influence on the reliability of test
results, consuming valuable healthcare resources and
compromising the patient's outcome. The pre analytic phase
enfolds the greatest potential for quality improvement.
Pre analytical variables can dramatically affect the results of
any laboratory test
Outcomes of pre-analytical errors range from no detected harm
to death
5. Pre-analytical errors (Contd…)
Patient Identification
Patient Preparation
Selecting the Site
Site Preparation
Tourniquet Application and Time
Proper Venipuncture Technique
Order of Draw
Proper Tube Mixing
Correct Specimen Volume
Proper Tube Handling and Specimen Processing
Serum Samples
Plasma Samples
Centrifugation
Special Handling of Blood Samples
Stability for Whole Blood, Serum and Plasma
6. Pre-analytical errors (Contd…)
Patient Identification:
–
It is important to identify a patient properly so that blood is
being collected from the correct person. Drawing blood from
the wrong person or labeling the correct patient’s sample
with a different patient’s label can certainly contribute to
laboratory error. Blood should not be drawn from a patient
before confirming that he is the right person. A nurse,
physician, relative or guardian should identify patients that
are unable to speak or identify themselves.
7. Pre-analytical errors (Contd…)
Patient Preparation:
–
Prior to collecting specimens for chemistry, certain patient
variables need to be considered. For certain chemistry
analytes, such as glucose and cholesterol, patients need to
be fasting (absence of food and liquids) for at least 12 hours
prior to veni-puncture. Other analytes, such as cortisol and
adrenocorticotropin, have diurnal variations, where the
analyte is at its highest level in the morning, and the levels
gradually decrease during the course of the day.
8. Pre-analytical errors (Contd…)
Selecting the Site:
–
Selecting the appropriate site for venipuncture can
contribute to a better quality sample. The preferred site
is the median cubital vein. This vein is usually the easiest to
access. Generally, there is less need to probe to find the
vein, which in turn should cause fewer traumas during the
venipuncture. This will usually be the most comfortable for
the patient. If the median cubital vein cannot be used, the
next choice would be the cephalic vein. . The last vein to
consider for venipuncture is the basilic vein. This vein is in
close proximity to the median nerve and brachial artery, and
extreme caution must be used so that only the basilic vein
is being punctured.
9. Pre-analytical errors (Contd…)
Site Preparation:
–
Prior to venipuncture, the site should be cleansed with
alcohol. Cleansing starts at the center of the vein, and
should continue outward in concentric circles. Before
performing the venipuncture, the alcohol should be allowed
to air dry. This will help to ensure that the specimen is not
contaminated with alcohol, as this can lead to hemolysis.
Hemolysis can result in the spurious elevation of such
analytes as potassium, lactate dehydrogenase (LD), iron
and magnesium in the chemistry lab. Allowing the alcohol to
dry completely will also cause less burning and pain to the
patient.
10. Pre-analytical errors (Contd…)
Tourniquet Application and Time:
–
The tourniquet should be applied approximately three to
four inches above the venipuncture site. The tourniquet
should be on the arm no longer than one minute. A good
rule of thumb to determine the one-minute tourniquet time is
to remove the tourniquet when blood starts to flow into the
first tube of blood being drawn. Prolonged tourniquet time
can lead to an increase in various chemistry analytes,
including serum protein, potassium and lactic acid due to
heam concentration of blood at the puncture site.
11. Pre-analytical errors (Contd…)
Proper
–
Venipuncture Technique:
During phlebotomy, avoid probing to find the vein
and achieve blood flow. Excessive probing and/or
“fishing” to find a vein can result in a poor quality
sample, including hemolysis. As mentioned
previously, hemolysis can affect several chemistry
analytes.
12. Pre-analytical errors (Contd…)
Order of Draw:
According to BD and CLSI (Clinical and Laboratory
Standards Institute, formerly NCCLS), following is the correct
order of draw during venipuncture will help to ensure accurate
test results. Improper order of draw that can lead to an incorrect
chemistry result is drawing an EDTA tube prior to a BD SST or
heparin tube for chemistry testing. The potential cross
contamination of K2 or K3EDTA on the needle from the
lavender top tube to the chemistry tube can lead to an elevated
potassium result. This in turn can require a recollection of the
sample, or possible misdiagnosis or treatment of the patient.
13. Pre-analytical errors (Contd…)
Proper Tube Mixing:
–
All tubes with additives need to be inverted to mix the
additive evenly with the blood. Plastic serum tubes and BD
SST tubes contain clot activator and should be inverted 5
times to mix the activator with the blood and help the
specimen clot completely. Improper mixing of the tube after
venipuncture could have contributed to the gelatinous
serum sample. Other additive tubes, such as heparin, need
to be inverted 8-10 times to mix the anticoagulant with the
blood and prevent clotting. Be sure that tubes are not being
shaken vigorously, as this can lead to a hemolyzed sample.
14. Pre-analytical errors (Contd…)
Correct Specimen Volume:
–
All blood collection tubes need to be filled to the correct
volume. This will ensure the proper amount of blood for the
amount of additive in the tube (blood to additive ratio). For
example, if a 5 mL draw heparin tube is only filled with 3 mL
of blood, the heparin concentration is erroneously high and
may potentially interfere with some chemistry analytes.
Expiration dates should also be checked on the evacuated
tubes. Expired tubes should not be used, as they may have
a decreased vacuum, as well as potential changes in any
additives in the tubes.
15. Pre-analytical errors (Contd…)
Proper
Tube Handling and Specimen
Processing:
–
Once the blood collection tubes have been drawn
in the correct order, to the proper fill volume and
mixed thoroughly, the next step toward accurate
test results is processing the tubes properly.
Serum and plasma tubes would be discussed
separately, as both specimen types have their
own special handling requirements.
16. Pre-analytical errors (Contd…)
Serum Samples:
Serum specimens, namely red top tubes and BD SST gel
tubes, need to clot completely prior to centrifugation and
processing. Blood specimens in red top tubes should clot for 45
to 60 minutes, and those in BD SST tubes should be allowed to
clot for 30 minutes to ensure complete clot formation. Blood
from patients who are receiving anticoagulant therapy, such as
heparin may take longer to clot. Tubes should be allowed to
clot at room temperature, upright in a test tube rack, with the
closures on the tubes. In the gelatinous sample, the blood does
not clot completely prior to centrifugation because a cardiac
patient is often heparanized. Spinning the tube too soon may
result in a gelatinous and/or fibrinous serum sample that will
require re-spinning.
17. Pre-analytical errors (Contd…)
Plasma
–
Samples:
Plasma specimens collected in plasma tubes,
such as the plain heparinized green top tubes and
the BD PST tubes with heparin and gel do not
require clotting prior to centrifugation. This allows
the tube of blood to be drawn, mixed and
centrifuged immediately, resulting in a quicker
turn-around-time for test results.
19. Pre-analytical errors (Contd…)
Special Handling of Blood Samples:
Certain chemistry analytes will require the tube of blood to
be chilled after collection in order to maintain the stability of the
analyte. A slurry of ice and water is recommended for chilling the
tubes of blood. Examples of specimens that need to be chilled or
transported on ice include adrenocorticotropic hormone (ACTH),
angiotensin converting enzyme (ACE), acetone, ammonia,
catecholamines, free fatty acids, lactic acid, pyruvate and rennin.
Other anayltes are photo-sensitive, and need to be protected
from light in order to remain stable and to ensure that the
laboratory reports an accurate result. This can be done by
wrapping the tube of blood in aluminum foil. The most common
example of a light-sensitive analyte is bilirubin. Other chemistry
analytes that need to be light-protected include beta-carotene
and erythrocyte protoporphyrin.
20. Pre-analytical errors (Contd…)
Stability for Whole Blood, Serum and Plasma:
A whole blood specimen that is going to be spun down should be
centrifuged and the serum or plasma removed from the red blood cells
within two hours after the venipuncture. Once the serum is removed or
separated from the red blood cells (in the case of a gel barrier tube), the
sample will be stable at room temperature for eight hours, and up to 48
hours at 2-4 degrees C. After 48 hours, the serum specimen should be
frozen at –20 degrees C in an aliquot tube.
Paying close attention to the pre analytical variables associated with
blood collection will help to ensure accurate test results in the chemistry
department, as well as all areas of the clinical laboratory. As was
evident, there are often several variables that can potentially contribute
to erroneous test results. Therefore, it is important to remember that a
better quality sample during the preanalytical phase of blood collection
will yield a better test result.