mls 322 exam 1

analyte

substance being tested

anticoagulant

prevents or delays blood coagulation

turnaround time

time taken from blood draw to reporting of results

hemotology

study of blood and relations of the bone marrow to the systemic circulation, relations of plama environment to RBC life span and relation of hemoglobin to the RBC

blood

window to body & predictior of vitality

ocular/ eye piece

provide initial 10x magnification

diaphragm apparatus

increase or decrease volume of light directed toward image, useful when examining cell structures in nucleus that needs more light

10x objective

used for locating feathered edge & gross slide abnormalities

40x objective

scanning and estimating counts

50x objective

oil mag

100x objective

fine microscopic work (oil objective)

magnification number

how large the image appears and how much of the viewing field can be observed

numerical aperture

resolution power of objective, objective ability to gather light and distinguish objects in close proximity.

tube length

distance from eye piece to objective

iris diaphragm

Increase or decrease the amount of light. amount of light may be desirable depending on source of sample.

adjustment knobs

moves stage horizontal or vertical

fine adjustment knob

moves stage left or right, for use after focus, used to get clarity

coarse adjustment knob

moves stage up and down, uses 10x objective

corrective actions for using microscope

-cant see image-turn slide over

-fine details cant be detected in immature cells- use 100x and fully open diaphragms

-40x obj is blurry- wipe w/ lent free paper

-particles on slide that arent large enough to be platelets - clean eyepieces

Microscope care

rest on a level, nonvibrating surface, secure bottom, and hold arm w/ other hand; never drag dry high obj’s across slides that contain oil; high dry obj never uses oil, oil objs wiped clean with lens paper only; eyepieces are cleaned with lens paper after each viewing; never wrap cords around objs or oculars

standard precautions

Treat all specimens as a potential source of infection, Proper PPE (gloves, masks, eye/face shields, countertop shields, fluid-resistant gowns/labcoats), and handwashing

gloves

worn during activities that involves contact body fluids, change immediately if contaminated or damaged and after pt contact, removed b4 exiting lab

gowns/labcoats

fluid-resistant long sleeves and wrist cuffs, not worn outside of lab, changed if they become contaminated or torn, treated as disposable biohazards

Splash/shields

goggles, face shields and plexiglass countertops, minimize risk of aerosol and specimen splashes

handwashing

highly effective first step against contamination; use soap and warm water 10-15 sec, should occur before and after each pt encounter, when gloves are taken off and anytime ungloved hands becomes contaminated

saftey precautions

Puncture-resistant containers for sharps, protection of mucus membranes, no smoking, eating, drinking, or chewing gum; keep loose papers and notebooks out of the lab; long hair tied back, fingernails trimmed, and beards trimmed; no dangling jewelry or rings; no applying lip balm.

quality assurance

comprehensive and systematic process that strives to ensure reliable patient results

quality assurance indicators

‒ Number of labeling errors

‒ Errors in data entry

‒ Testing turnaround times

‒ Proficiency testing performance

‒ Standardized competency testing

quality control monitoring

process of analyzing control specimens with known target values (normal and abnormal) along with pt samples to evaluate assay precision and accuracy, detect analytical errors or trends, and ensure valid lab results before release

quality control components

standards/calibrators, control materials, statistics

standards/calibrators

solutions have a known amount of analyte, sets the base normal for analyte

control materials

include at least one normal and abnormal level, analyzes and detects correct known level of analyte to verify instruments are correctly working.

statistical quality control system

establish target range for analyte; data points should cluster around the central tendency (measured by mean, median, and mode); represents normal distribution of data

mean

arithmetic average

median

middle value

mode

most frequent value

standard deviation (SD)

precision measurement that describes the average distance of each data point from the mean in normal distribution

coefficient of variaton (CV)

SD expressed as a percentage, lower = more precise data; usually less than 5%

accuracy

closest to true value

precision

reproducibility and repeatability of test samples; great value= compromised

reference intervals

range of results that are considered normal for a specific population; established for a particular analyte, method, or instrument

delta checks

comparison btw current pt results and previous pt results; allows operator to detect large variations; key to identifying preanalytic errors; provide opportunity to identify a reason for variations before releasing results

potential causes of delta checks

misidentified samples, analytic errors, or changes in the pt condition

reflex testing

additional testing to verify abnormal results (may require manual verifications)

critical values

marked results decreased or increased from the reference range; marked different from pt result history; automatically flagged by machines; notify someone immediately; determined by each laboratory

preanalytic values

affect samples before testing

examples of preanalytic values

proper pt identification

properly labled tubes

proper anticoagulant

proper mixing of sample

timely delivery

tube checked for clots

medication administered to pt

previous blood transfusion

intravenous line contamination

proper collection of blood sample

postanalytic variables

occur after sample testing; lead to poor pt care

postanalytic variables examples

proper documentation of test results

timely reporting ( if critical results observed)

proper handling of samples

delta checks

reflex testing

specimen check for clots

results released

which is a violation of standard precautions

applying cosmetics

The role of calibrators, standards, and quality control materials is to:

Define analyte values for instruments

#1

oculars/eyepiece

#2

coarse adjustment knob

#3

fine adjustment knob

#4

stage adjustment knobs

#5

base

#6

light source

#7

condenser

#8

iris diaphragm

#9

stage

#10

objectives (10x, 40x,100x and sometimes 50x)

Dangling jewelry or long hair are possible sources of contamination or injury if caught in machines

true

error analysis, standard protocol and turnaround time is part of the

quality assurance system

normal disturbution curve will have 99.7% of measured values fall w/in 2 standard deviations distribution

false

normal distribution curve

68% within the mean one SD from the mean

95.5% within the mean and two SDs (2SD) from the mean

99.7% within the mean and three SDs (3SD) from the mean

saftey training include includes

precautions to prevent bloodborne pathogen exposure, proper use of PPE, and evacuation routes incase of fire

When handwashing after a patient contact, the soap application process should last at least:

10-15 seconds

Which of the following is not considered a postanalytic variable?

Collection of specimens with appropriate anticoagulants

Reflex testing is used in the hematology laboratory to

Immediately order additional testing to verify abnormal results

acrocyanosis

blue or purple mottled discoloration of fingers toes or nose or all 3

hepatosplenectomy

spleen enlargement and liver

hypoxia

decreased oxygen

reticuloendothelial system (RES)

system of fixed macrophages and circulation monocytes that serve as phagocytes

hematopoiesis

production, development, differentiation, and maturation of all types of blood cells

bone marrow

can produce 3 billion red blood cells, 1.5 billion white blood cells, and 2.5 billion platelets per day per body weight; extremly versatile and serves the body well by supplying life-giving cells w/ a multiplicity of funtions

Within the basic bone marrow structure lies the mechanisms to

Supply the peripheral circulation constantly with mature cells.

Mobilize the bone marrow to increase production if hematological conditions warrant.

Compensate for decreased hematopoiesis within the bone marrow by recruiting other hematopoietic sites (non-bone marrow sites, liver, and spleen)

intramedullary hematopoesis

w/in bone marrow

extramedullary hematopoiesis

outside bone marrow; primarily in liver and spleen in adults; can cause hematosplenectomy (indicator that hematological health is compromised)

early fetal development hematopoiesis mesoblastic period

2 wk-2 mth-yolk sack

early fetal development hematopoiesis, hepatic period

2mth- 7mth- spleen, liver, thymus, and lymph nodes

Late fetal development—adult life hematopoiesis

7mth- birth- adult bone marrow

Hematopoietic function of the spleen

RBC filtration—red pulp, lymphocyte processing—white pulp, stores WBC and platelets—marginal zone; produce WBC RBC or platelets if necessary.

Reservoir function of the spleen

stores one-third of platelets and granulocytes, able to mobilize platelets into circulation if necessary.

Filtration function of the spleen

gets rid of abnormal cells

Immunologic function of the spleen

supplies opsonizing antibodies, promotes phagocytic activity, and provides protection, possibly leading to serious concequences.

splenectomy risks

OPSIs may occur w/in 3 yrs; many die bc spleen cant play vital role; abnormal RBCs present ; WBC and platelets have to fine another storage site.

bone marrow

consists of yellow marrow (fat/not active), red marrow (active), and intricate supply of nutrients and blood vessels; root of hematological disease; contains RBC, WBC, and platelets of various stages along with osteoclasts, stroma, and fatty tissue; responds to anemia

bone marrow in long bones

first 18 yrs

bone marrow in iliac crest and sternum

18+ years

myeloid:erythroid ratio (M:E ratio)

can predict hematological problems; normal ratio 3:1 to 4:1

Erythroid hyperplasia

Anemia stimulates the body to produce erythropoietin (EPO) to increase red blood cells; ↑ immature red blood cells in circulation; Abnormal in peripheral circulation: nucleated red blood cells, reticulocytes, and polychromasia

polychromasia

nucueated RBC; indicates bone marrow response to an event

Lymphoid precursors

T cells or B cells

T cells

responsible for cellular immunity (cell-cell communication)

B cells

responsible for humoral immunity (production of antibodies

Nonlymphoid precursors

GEMM (granulocyte, erythroid, monocyte, megakaryocyte)

cytokines and interleukins

uniquely responsible for promoting a specific lineage of cell (RBC production); used to stimulate specific cell production to yield theraputic benefits

specific conditions in which recombinant cytokines have been useful

Treatment of graft-versus-host disease after bone marrow transplant therapy

Increasing white blood cell counts (WBCs) in patients with AIDS on antiretroviral therapy

Stimulation of red blood cell production for chronically anemic patients and chemotherapy patients

Recovery from neutropenia resulting from myelotoxic therapy

Erythropoietin (EPO)

Cytokine; Hormone produced by the kidneys; Stimulates red blood cell production; Available as a pharmaceutical product

kidney detect hypoxia

increase EPO and production of RBC