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What is the equation for oxygen delivery to tissues?

Cardiac Output x Oxygen Content
DO2 = CO x CaO2

What are the two main compartments that get oxygen out to tissues?

Hemoglobin and Plasma

Hemoglobin Equation

1.34 x Hb x SaO2

Plasma Equation

.003 x PaO2

Plasma or Dissolved Compartment

O2 physically dissolved into blood, in capillary area.
Henry's Law
PO2

Hemoglobin or Combined Compartment

O2 chemically attaches to hemoglobin, can load up in lungs and unload. 98% of O2 carried this way.
Each gram of Hb can carry 1.34 ml of O2
Normal = 15 grams% per 100 ml of blood.
HCT / 3 =Hb.

As PO2 goes up your PaO2 goes up T or F

True, there is a direct relationship

For every 100 ml of blood 5 vol% are extracted
T or F

True, this is the A-V difference

What is normal CvO2?

15 vol%
Right Heart

What is normal CaO2?

20 vol%
Left Heart

Normal O2 Consumption

250 ml/min

Normal CO2 production

200 ml/min

What is normal Cardiac Output? CO

5 LPM

Venous Blood SvO2? PvO2?

75%
40 Torr

Arterial Blood SaO2? PaO2?

97%
90 Torr

What % of Cardiac Output doesn't participate in gas exchange?

2-5%

What is Venous Ad mixture?

Oxygenated and NonOxygenated blood mixed

Shunt

Perfusion without Ventilation

What is the Transit time?

Less than 1 second
It is how long the RBC is in contact with the area where gas exchange takes place.

How many Hb molecules are in each RBC?

280 Million

How many molecules can the Hb hold? Atoms?

4 molecules or 8 atoms

Hb isn't fully saturated until what PO2?

150

Carbon Monoxide has what affinity ?

250x more than oxygen

Define Reduced Hb

Uncombined or deoxygenated Hb
Hb not bound with O2

Oxyhemoglobin Dissociation Curve

Relationship between PO2 and SO2

PO2 of 60

Is SaO2 of 90
if curve is normal

P50

What PO2 does it take to saturate hemoglobin to 50%
pH has a big effect on P50
When normal P50 is 27 Torr

Explain the steep part of the curve

How a small change in PO2 can cause a big change in the SaO2

Pulse Oximeter

Tells how much your hemoglobin is saturated

Shift to Right

P50 goes up. Makes it easier to give up O2, at tissue level

Shift to Left

P50 goes down. Holds onto O2 tighter. Loads up easier at capillary level.

Left Shift Causes

High- pH Low-PCO2, Low-Temp, Low-DPG,
HbF-(Fetal)
COHb

Right Shift Causes

Low-pH High-PCO2, High Temp, High-DPG

DPG

Contained inside RBC
Hb affinity for O2 decreases as DPG increases

Factor affecting CaO2-Anemia

Only 1/2 as much ability to do O2 transport by reducing amount of Hb to carry O2

Factor affecting CaO2-Polycythemia

Opposite of anemia, Increases Hb unless a result of Chronic Lung Disease

Factor affecting CaO2-Cyanide

Blocks ability of cells to uptake O2 at mitochondrial level
A-V difference becomes zero

Factor affecting CaO2-Altitude

Increases Hb over time, but SaO2 and PaO2 stay low.
Increase altitude =decrease PIO2
Short term= SaO2 and PaO2 decreases

Factor affecting CaO2-Hyperbarics

Only slightly affects SaO2 but affects plasma significantly

Factor affecting CaO2- Carbon Monoxide

Hb affect cant do O2 transport because its bound up with Carbon Monoxide PO2 not reliable anymore

If you keep the numbers the same and you reduce Co what happens?

Only half as much O2 is delivered, but the content is the same. When CO decreases your DO2 changes.

Factors that decrease the SvO2

Decreased CO, Periods of increased O2 consumption
Exercise, Seizures, Shivers, Hyperthermia

4 Types of Hypoxia

Hypoxic Hypoxia
Anemic
Circulatory
Histotoxic

Hypoxic Hypoxia

Low Alveolar PO2, Diffusion Impairment, V/Q Mismatch
Alveolus problem, blood doesnt have access to O2
Fix=Increase FIO2

Define Hypoxia

Low O2 at the cellular level

Define Hypoxemia

Low O2 in the blood

What is the greatest cause of Hypoxia in the hospital

V/Q Mismatch

Anemic Hypoxia

Low O2 at cellular level because of anemia
Blood carrier problem, Low Hb, Inability of Hb to carry O2
Ex. Carbon monoxide poisoning

How to treat Carbon Monoxide Poisoning

1st-get out of area to fresh air
2nd-Use non-rebreather to give highest FIO2 possible
3rd-Evaluate need for Hyperbaric chamber

Circulatory Hypoxia (Stagnet)

Arterial Venous Shunting-instead of going to tissues arterial blood goes back to venous blood circulation
Blood doesnt circulate well
No adequate perfusion to the core during CPR

Histotoxic Hypoxia

Classic Example-Cyanide poisoning
Tissues cant uptake O2
Cyanide doesnt allow the cells to utilize the oxygen delivered

Define what makes you Cyanotic

5 grams% reduced Hb in 100 ml of blood

Define OxyHb

Combined or Oxygenated Hb
Hb bound with O2

CarboxyHb

Carbon Monoxide bound to Hb

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