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PHYSIOLOGY OF BLOOD III
Hemoglobine & oxygen delivery
ROLE OF HEMOGLOBIN (HB)
 Transports
oxygen in body
 acido-base
buffer
 98%
of oxygen is bound to
Hb allosterically
 2%
is solved in plasma
 135
– 170 g/l in men
 120
– 160 g/l in women
HEMOGLOBIN
•
4 polypeptic chains - subunits

2  chains

2  chains
•
Each subunit contains 1 heme
•
1 hemoglobin binds 1.36ml of O2
•
Other chains?

Fetal - 22

Adult - 22, 22d (2%)

Embryonic - 2z2e, 22e, 2z2
STATE OF THE QUARTER STRUCTURE

Deoxyemoglobin – dark red

Oxyhemoglobin – light red

Reduced hemoglobin

ferro- Fe2+ and ferri-hemoglobine Fe3+

Methemoglobin (ferri state)– gray cyanosis

Carboxyhemoglobin – light red, CO bound

Carbaminohemoglobin – dark red, CO2 bound

Other: cyanide (CN-), sulfur monoxide (SO), nitrogen
dioxide (NO2), and sulfide (S2-), hydrogen sulfide (H2S)
CYANOSIS

It is associated with the presence of deoxyhemoglobin in
organism

Cyanosis – when amount of deHb is more than 50g/l

It is about the absolute value

What does that mean?
Conformational change and O2 binding
Oxygen binds to heme and so it brings Fe atom closer to
heme, what will lead to conformation change and
stabilization of 1 heme unit
One Hb subunit will then expose the other subunit (the
reason for sigmoid shape curve of oxygen saturation)
If one oxygen molecule binds Hb, the second will bind
easier
HEMOGLOBIN SATURATION CURVE
, 2,3 BPG 
OXYGEN DELIVERY TO ORGANISM

O2del=(SVxHR) x Hbconc x 1.36 x SpO2
e.g. HR=70bpm; Hbconc=150g/L; SpO2=98%

O2del =(0.07[L] x 70) x 150 [g/L] x 1.36 [ml] x 0.98
= 979,608 ml/min
SV – stroke volume [L]
HR – heart rate [beats per minute]
Hbconc – hemoglobin concentration in blood [g/L]
1,36 – mls of oxygen bound to 1g of hemoglobine
SpO2 – % saturation of hemoglobine by oxygen
REMEMBER!!!!
OXYGEN DELIVERY

OXYGEN CONSUMPTION
PULSE OXIMETRY

pulse oximeters non-invasively measure the arterial oxygen
saturation of haemoglobin

simple, portable, non-invasive, fast

basic examination

procedural anaesthesia

intensive care & emergency rooms
Limitations

dyshemoglobinemias

hypotension

fingernail polish

movement

visible light interference
PULSE OXIMETRY - PRINCIPLE
the absorption of light at two different
wavelengths by haemoglobin differs
depending on the degree of oxygenation
of haemoglobin
http://www.microchip.com/stellent/idcplg?IdcService
=SS_GET_PAGE&nodeId=2723
SpO2 = (O2Hb / (O2Hb + Hb)) x 100%
Tremper KK, Barker SJ:Pulse oximetry.
Anesthesiology. 1989 Jan;70(1):98-108.
PULSE OXIMETRY - PRINCIPLE
http://www.microchip.com/stellent/idcplg?IdcService
=SS_GET_PAGE&nodeId=2723
Tremper KK, Barker SJ:Pulse oximetry.
Anesthesiology. 1989 Jan;70(1):98-108.
CONTEC CMS 50D PULSE OXIMETER
Arterial saturation of
hemoglobin with
oxygen value display
Heart rate
value display
ON button
Display mode
change button
Heart rate signal
control bar
Pletysmograph
wave
PULSE OXIMETRY

Possible waveform readings
and interpretation
http://www.ebme.co.uk/arts/nellcor/nellcor3.htm
OTHER OXIMETERS
DETERMINATION OF HB CONTENT

25 ml of capillary blood

15ml of Drabkin solution

Change of all hemoglobin forms to methemoglobine and finally to
cyanmethemoglobine in alkalic environment

Wait

Measure absorbance at 540 nm
HEMATOCRITE - HCT
Ratio of Erythrocytes to Whole blood!!!
Whole blood
erythrocytes
HEMATOCRITE

Men: 44 ± 5 % (0.44 ± 0.05)

Women: 39 ± 4% (0.39 ± 0.04)

Newborn: 55%

Gravidity: lower Hct

High altitude: higher Hct
HEMATOCRITE
 anemia
(lower number of red blood cells)
 trauma
 inner
bleeding evaluation
 polycytemia (higher number of red blood cells)
 response to the treatment of anemia or polycytemia
 1 blood transfusion = increase in hemotacrite by 3%
 dehydratation
 to or not to give transfusion decision
 if else healthy, transfusion is administered when
hemoglobin is lower than 80g/l and hematocrite
lower than 24%
HEMATOCRITE

Capillary blood to 2/3 of the capillary

Free end of the glass capillary to be burned

Centrifugation

Read and explain the result 
TEICHMANN CRYSTALS

Heating the dried blood in the presence of glacial acetic acid
nad NaCl to form hematin.

Capillary blood

Make it dry

Put NaCl and glacial acetic acid, heat

Wait

Observe under microsope

Rhombic crystals, brownish color
LEUKOCYTE COUNT

As ERY count, only....

Different solution

50 squares

Divide by 10 and multiply by 109, get No. of Leu in L of blood

Normal values 3,5 – 9 x 109/L blood
QUESTIONS?
1/--pages
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