Repiratory Assessment (Gas#1) Flashcards
Definition of Hypoxemia and what can it lead to?
low partial pressure of oxygen in the BLOOD; it can lead to hypoxia
Hypoxia
shortage of oxygen in TISSUES
What 2 things can cause hypoxemia?
inadequate ventilation (ex. trauma) & decreased perfusion (ex. decreased cardiac output, pulmonary embolism)
What can cause hypoxia?
Atelectasis, Anemia (no O2 carrying capacity), decreased cardiac output & toxic substances
S/s of Acute Hypoxemia
Increased HR, Increased RR, Anxiety/Restlessness
Example of Acute Hypoxemia
pneumothorax
S/s of Chronic Hypoxia
Fatigue, decreased level of consciousness, cyanosis, clubbing of finger & toes
Example of Chronic Hypoxia
COPD
Ventilation
movement of air in and out of the lungs and the exchange of gases
3 things that affect Ventilation
1.) Resistance 2.) Compliance 3.) Diffusion
Resistance affects what and what is it?
It effects ventilation it is determine by airway size. The narrower the airway, the greater the resistance
Compliance affects what and what is it?
It effects ventilation and determines how easily the lung can stretch. Increased compliance= decreased elasticity; decreased capacity= lungs/thorax are stiff
Diffusion affects what and what is it?
It affects ventilation and is the movement of gas from an area of greater concentration to lesser concentration.
example of problems that cause a decreased compliance
pneumothorax, hemothorax, pleural effuision. pulmonary edema, ARDS, atelectasis
Ventilation perfusion ratio
the ratio of the amount of AIR reaching the alveoli to the amount of BLOOD reaching the alveoli
Shunt
Ventilation is impaired but perfusion is adequate. The % amount of blood passing through the lung not oxygenated
Shunting& dead space leads to ?
hypoxemia
Severe hypoxemia = what shunt percentage?
> 20% and requires mechanical ventilation or PEEP
Dead Space
Ventilated but perfusion is decreased
When are ventilation and perfusion both absent?
Atelectasis
Pneumothorax
A collection of air or gas in the pleural cavity. Gas enters following a perforation though the chest wall, e.g. chest trauma
Atelectasis
A collapsed or airless condition of the lung
Consolidation
Alveolar space contains the fluid instead of air; you cant stick needle in & extract fluid because you’ll collapse the lung. you can suck it out through a broncioscope
Pleural effusion
Fluid accumulates between the pleura and the chest wall. This impairs breathing, limiting the expansion of the lungs.
Fluids that accumulate in the pleural space
Serous fluid, blood, pus-empyema
Fluids that can accumulate in the alveolar space
Edema, Exudate, Pus, Inhaled water, blood
Pleural effusions can be caused by
kidney disease, HF, cirrhosis, peritoneal dialysis, pneumonia, cancer TB