Page 690 - Clinical Hematology_ Theory _ Procedures ( PDFDrive )
P. 690
674 PART 8 ■ Fundamentals of Hematological Analysis
HEMATOLOGY PROCEDURES (continued)
A enough isotonic (0.85%) saline solution to the test concentration to calculate the mean corpuscular hemoglobin
tube or vial to prepare a 1% to 2% suspension o cells. concentration (MCHC).
3. A 22% albumin to the suspension at the rate o three Specimen
rops o albumin or each 10 mL o resulting cell suspen-
sion. I the amount o albumin is too great, the cells will Venous bloo anticoagulate with ED A or capillary bloo
appear too ark an may have pseu opo s. collecte irectly into heparinize capillary tubes can be
4. T is preparation can then be trans erre to the sample use . Specimens shoul be centri uge within 6 hours o col-
hol er an treate accor ing to the instrument manu ac- lecting. Hemolyze samples cannot be use or testing.
turer’s irections. Reagents, Supplies, and Equipment
Clinical Applications 1. Capillary tubes (75 mm long with an ID o 1.155 mm).
Selecte isor ers associate with increases in normal leu- Blue-ban e tubes contain no anticoagulant an are use
kocyte types are with ED A-anticoagulate bloo . Re -ban e tubes are
heparinize or use with capillary bloo .
Neutrophils 2. Clay-type tube sealant.
1. Bacterial in ections 3. Microhematocrit centri uge an rea ing evice.
2. In ammation Calibration
3. Stress T e calibration o the centri uge shoul be checke regu-
4. Chronic leukemia
larly or timer accuracy, spee , an maximal packing o cells.
Lymphocytes Use a stopwatch or accuracy, a tachometer or spee , an
1. Viral in ections a time versus constant volume metho to check packing o
2. Whooping cough erythrocytes. Check the capillary tube rea ing evice against
3. Chronic leukemia another rea er perio ically.
Quality Control
Monocytes
1. uberculosis Commercially available whole bloo can be use to check the
accuracy o normal an abnormal levels.
2. Rheumatoi arthritis
3. Fever o unknown origin Procedure
1. Well-mixe anticoagulant bloo shoul be rawn into
Eosinophils two microhematocrit tubes by capillary action. T e tubes
1. Active allergies shoul be f lle to about three ourths o their length.
2. Invasive parasites Wipe o the outsi e o the tubes with gauze or wipes.
Basophils Free- owing capillary samples shoul be collecte in the
1. Ulcerative colitis same manner.
2. Hyperlipi emia 2. Seal one en o each tube with a small amount o clay-like
material. Place the ry en o the tube into the sealant,
hol ing the in ex f nger over the opposite en to prevent
BIBLIOGRAPHY bloo rom leaking out o the tube onto the sealant.
3. Place the f lle an seale capillary tubes into the centri-
Provi e on this book’s companion Web site at http://thepoint. uge. T e seale en s shoul point towar the outsi e o
lww.com/ urgeon6e. the centri uge. T e uplicate samples shoul be place
opposite each other to balance the centri uge. Recor the
PACKED CELL VOLUME OF WHOLE BLOOD: position number o each specimen.
MICROHEMATOCRIT METHOD 4. Securely asten the at li on top o the capillary tubes.
Principle Close the centri uge top an secure the latch. Set the timer
T e packe cell volume (PCV) is a measurement o the ratio or 5 minutes. T e f xe spee o centri ugation shoul be
o the volume occupie by the RBCs to the volume o whole 10,000 to 15,000 rpm.
bloo in a sample o capillary or venous bloo . Following 5. A er the centri uge has stoppe , open the top an remove
centri ugation, this ratio is measure an expresse as a per- the cover plate. Promptly rea the PCV on an appropriate
centage or ecimal raction. Clinically, the PCV is use to piece o equipment or specially esigne car . Measure
etect anemia, polycythemia, hemo ilution, or hemoconcen- the PCV by a justing the top o the clay sealant to the zero
tration. In conjunction with an erythrocyte count, the PCV mark an rea ing the top o the re cell column. A rea er
is use to calculate the mean corpuscular volume (MCV). with an ocular that has cross-markings pro uces the most
Te PCV is also use in conjunction with the hemoglobin accurate rea ing.
