Respiration And Blood Gas Analysis

Front 1

Ventilation vs. respiration

Back 1

Ventilation = mechanical process of moving air in and out of lungs

Respiration = exchange of gas (at alveoli in lungs) between the atmosphere and capillaries

Front 2

What allows the lungs to inflate?

Back 2

Lungs have a surfactant. It's a phospholipid-lipoprotein complex that lines alveoli to reduce surface tension. Allows for easy inflation.

Front 3

Fetal lung maturity test?

Back 3

Lecithin/sphingomyelin ration (LS ratio)

ref range > 2.0 for mature lungs

premature babies often have under developed lungs and lack surfactant.

Front 4

Gas exchange in lungs - describe

Back 4

Gases diffuse from areas of high concentration to low concentration.

Atmospheric O2 > lung/blood O2

Atmospheric CO2 < lung/blood CO2

Front 5

Factors influencing gas transfer in lungs

Back 5

• destruction of alveoli (surface area for gas exchange reduced)
• pulmonary edema
• airway blockage
• inadequate blood supply

Front 6

Blood Gas Analysis - what values are measured and/or calculated?

Back 6

Measured

• pH
• Partial pressure O2
• Partial pressure CO2

Calculated:

• HCO3
• Base excess
• Saturated O2
• FIO2

Front 7

What is P50

Back 7

P50 is the partial pressure of oxygen at which hemoglobin is 50% saturated with oxygen

Front 8

What accounts for the total concentration (TCO2) of CO2 in blood?

Back 8

bicarbonate and partial CO2

Front 9

oxygen saturation - definition

Back 9

Amount of oxygen bound to hemoglobin

Front 10

Anion gap - definition and calculation

Back 10

Total measured cations - total measure anions

= ([Na+] + [K+]) - ([Cl-] + [bicarb or CO2])

reference value approx 12 mEq/L

Front 11

Hyper/hypochloremia

Back 11

Increased or decreased chloride

Front 12

Hyper/hypokalemia

Back 12

Increased or decreased potassium

Front 13

Hyper/hyponatremia

Back 13

Increased or decreased sodium

Front 14

Hyper/hypocapnia

Back 14

Increased or decreased carbon dioxide

Front 15

Base excess (BEecf)- definition

Back 15

calculated parameter, assess metabolic component of bicarbonate

normal range -2 to +2 mEq/L

excess of bicarbonate (positive base excess)

deficit of bicarbonate (negative base excess)