ERYTHROCYTE SEDIMENTATION RATE AND PACKED CELL VOLUME

OBSERVATION

Withdraw blood and place in tube

1 2 Centrifuge

Plasma(55% of whole blood)

Formed elements

Buffy coat:leukocyctes and

platelets(<1% of whole blood)

Erythrocytes(45% of whole blood)

• Hematocrit • Males: 44%(38—50%)

• Females: 42% (36—45%)

PCV / PACKED CELL VOLUME / HAEMATOCRIT

High Speed Haematocrit centrifuge

Capillary Haematocrit Tube

Erythrocyte sedimentation rate (ESR) is a non-specific test for inflammation.

It is easy to perform, widely available and inexpensive making it a widely used screening test

It is also used a monitoring tool for response to treatment in conditions in which it is raised (tuberculosis, autoimmune diseases etc(

Basics:

The ESR test is performed in the laboratory by placing anticoagulated blood in an upright tube (Westegren's most often). At the end of an hour of this, the rate of the RBC sedimentation is measured

ERYTHROCYTE SEDIMENTATION RATE (ESR)

Nonspecific test for inflammatory process

anticoagulated blood in calibrated tube; rate of sedimentation of RBCs in 1 hour

normal <15m;<20f; add 10 past age 60

SEDIMENTATION PHASES

The initial lag phase .(10m)

The phase of rapid RBC falling(40m)

The packing phase (10m).

REFERANCE RANGE

Adult females 0-20 mm/h

Adult males 0-15 mm/hr

Children(<10) 0-10 mm/hr

The aggregated RBCs in the rouleaux formation have a higher ratio of 'mass to surface area' as compared to single RBCs and hence sink faster in plasma.

ESR of more than 100 mm/hr is strongly associated with serious underlying disorders like connective tissue disease, infections and malignancies

ESR is helpful in diagnosing two specific inflammatory diseases, temporal arteritis and polymyalgia rheumatica.

SOME CONDITIONS WITH VERY HIGH ESR >100 MM/HR Multiple myeloma Connective tissue disorders - SLE, RA

and other autoimmune diseases Tuberculosis Malignancies Severe anemia

SOME CONDITIONS WITH LOW ESR:

Polycythemia Severe Leukocytosis Sickle cell disease (anemia). Hereditary spherocytosis Congestive cardiac failure Corticosteroid use Hypofibrinogenemia

DEFINITION Hematocrit is the fractional volume of blood

that erythrocyte occupy . Amount of packed red blood cells following

centrifugation.

When blood is centrifuged in a tube the red cells are packed together at the bottom of the tube by centrifugal force as cells are heavier than plasma.

It is a macroscopic observation by which the percentage volume of the packed red blood cells is measured.

APPARATUS AND MATERIALS Equipment for venepuncture ;-Sterile swabs, alcohol ,syringe and needle-Container (penicillin vial or bulb)-anticoagulant (Double oxalate/EDTA/ Sequestrene/

Heparin) Wintrobe tube; -Above downwards 0—10cm for ESR.-Above downwards 10—0cm for PCV. Pasteur pipette Centrifuge machine

OBSERVATION

Withdraw blood and place in tube

1 2 Centrifuge

Plasma(55% of whole blood)

Formed elements

Buffy coat:leukocyctes and

platelets(<1% of whole blood)

Erythrocytes(45% of whole blood)

• Hematocrit • Males: 44%(38—50%)

• Females: 42% (36—45%)

Thank you