Day 2: Oxygenation / Gas Exchange 🫁

Recall: Oxygenation

Oxygenation means getting enough oxygen into the blood so tissues can use it.

Recall: Ventilation

Ventilation means moving air in and out of the lungs.

Recall: Gas exchange

Gas exchange is the movement of oxygen from alveoli into blood and carbon dioxide from blood into alveoli.

Recall: Alveoli

Alveoli are tiny air sacs in the lungs where gas exchange happens.

Recall: SpO₂

SpO₂ is the oxygen saturation measured by a pulse oximeter.

Recall: Hypoxia

Hypoxia means tissues are not getting enough oxygen.

Recall: Dyspnea

Dyspnea means shortness of breath.

Thinking: How are ventilation and oxygenation different?

Ventilation is air movement, while oxygenation is oxygen getting into the blood.

Thinking: Why can pneumonia cause low SpO₂?

Pneumonia can fill alveoli with fluid, pus, or inflammation, making it harder for oxygen to cross into the blood.

Thinking: Why can COPD cause poor gas exchange?

COPD can damage alveoli and trap air, reducing effective oxygen exchange and carbon dioxide removal.

Thinking: Why does asthma make ventilation harder?

Asthma causes airway narrowing from bronchospasm, inflammation, and mucus, making it harder to move air.

Thinking: Why is PE a gas exchange problem?

A PE blocks blood flow to part of the lung, so oxygen cannot properly enter the blood in that area.

Thinking: Why can PE cause sudden shortness of breath?

The clot blocks lung blood flow, causing sudden poor oxygen exchange and increased strain on breathing/circulation.

Thinking: Why can low oxygen cause confusion?

The brain needs constant oxygen, so low oxygen can quickly cause restlessness, confusion, or decreased alertness.

Thinking: Why does respiratory rate increase when oxygenation is poor?

The body tries to breathe faster to bring in more oxygen and remove carbon dioxide.

Thinking: Why are crackles common in pneumonia?

Crackles can happen when fluid or secretions are present in the alveoli or small airways.

Thinking: Why are wheezes common in asthma and COPD?

Wheezes happen when air moves through narrowed airways.

Thinking: Why is accessory muscle use concerning?

It means the patient is working harder than normal to breathe.

Thinking: Why is a silent chest dangerous in asthma?

It may mean very little air is moving, which can signal severe airway obstruction.

Thinking: Why should nurses assess mental status in respiratory problems?

Confusion or restlessness can be early signs that the brain is not getting enough oxygen.

Thinking: Why should nurses not rely only on SpO₂?

SpO₂ is important, but nurses must also assess work of breathing, lung sounds, mental status, and overall deterioration.

Thinking: What should the nurse assess first in respiratory distress?

Assess airway, breathing, respiratory rate, work of breathing, SpO₂, lung sounds, and mental status.

Thinking: How does oxygen therapy help?

Oxygen therapy increases the oxygen available for the blood to carry to tissues.

Thinking: How do bronchodilators help asthma or COPD?

Bronchodilators relax/open the airways so air can move more easily.

Thinking: How do steroids help asthma or COPD exacerbations?

Steroids reduce airway inflammation, making breathing easier over time.

Thinking: How do antibiotics help pneumonia?

Antibiotics treat bacterial infection causing lung inflammation and impaired gas exchange.

Thinking: How do anticoagulants help PE?

Anticoagulants prevent the clot from growing and reduce the risk of new clots.

Thinking: Why is sitting upright helpful for shortness of breath?

Sitting upright allows better lung expansion and can reduce work of breathing.

Thinking: What does low SpO₂ plus confusion suggest?

It suggests the brain may not be receiving enough oxygen, which is urgent.

Thinking: What does low SpO₂ plus chest pain and sudden shortness of breath suggest?

It may suggest PE or another urgent cardiopulmonary problem.