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The P/F ratio of a patient with a PaO2 of 74 mm Hg on an FiO2 of 85%.
What is 87?
This is the formula for arterial oxygen content.
What is
CaO2 = (0.003 x PaO2) + (1.34 x Hb x SpO2)
Define Fick's Law of gas diffusion.
What is gas molecules moving across a membrane from high pressure areas to low pressure areas?
True or false: membrane thickness affects molecular ability to diffuse across it
What is true?
COPD and restrictive lung disorders may contribute to the presence of alveolar shunts due to this.
What is hypoventilation or inadequate minute ventilation?
The ventilator tubing was dirty and changed out with a longer circuit. The patient now presents acidotic because this has occurred ...
What is increased dead space and/or the need for increased minute ventilation?
A normal value of 16-20 represents this.
What is the normal range for arterial oxygen content?
Five factors that affect the loading and offloading of oxygen
What is blood pH, body temperature, erythrocyte concentration, structure/shape of hemoglobin, and adverse hemoglobin chemical combinations?
A decrease in this compound causes a barrier in offloading oxygen to tissues because of an increased affinity for oxyhemoglobin.
What is 2,3- DPG?
This type of shunt sends venous blood into the left heart to mix with arterial blood.
What is a physiologic shunt?
"Bronchial venous drainage"
A mountain hiker is experiencing hypoxia at a barometric pressure of 668. Calculate the alveolar air equation for this hiker if he is breathing room air and has a PaCO2 of 58 mm Hg.
What is 58?
Respiratory therapists determine a patient's level of hypoxemia by calculating this- clue: it's used regularly for ARDS patients.
What is the P/F ratio?
Bicarbonate is necessary to buffer and transport this during expiration.
What is CO2?
This condition hardens and changes the shape of hemoglobin, and increases the risk of clot development.
What is sickle cell?
This combination with hemoglobin increases the affinity for oxygen yet loses oxygen binding capacity due to the presence of ferric ions.
What is methemoglobin?
The presence of this is why young infants may have a left shift on the oxyhemoglobin curve that shows a greater affinity for oxygen with less tissue oxygen unloading.
What is fetal hemoglobin?
The "magic number" of oxygen dissolved arterial blood, and the amount of oxygen a single hemoglobin can carry.
What is 0.003 and 1.34?
True or false: tissue hypoxia does not occur when PaO2 is normal
What is false?
(think of blood loss or variant Hb)
The presence of this easily displaces true oxygen carrying capacity by half because it has a significantly greater affinity for hemoglobin binding.
What is carboxyhemoglobin?
What is increased ventilation and decreased perfusion?
The goal PaO2 respiratory therapists try to help their patients achieve or maintain.
What is above 60 mm Hg?
The name of the enzyme that breaks CO2 into H+ and HCO3 during hydrolysis.
What is carbonic anhydrase?
A condition where cardiac output or perfusion is decreased and leads to hypoxia.
What is shock and/or ischemia?
This mineral ion is necessary to maintain electrolyte equilibrium as CO2 buffering and transport occurs.