Oxygenation and Respiratory Nursing Care

These question-and-answer flashcards review core concepts of oxygenation, respiratory anatomy and physiology, factors affecting gas exchange, nursing assessments, and key interventions such as chest physiotherapy, suctioning, incentive spirometry, and oxygen therapy.

What percentage of the ambient air we breathe is composed of oxygen?

Approximately 21%.

Which three body systems integrate to deliver oxygen and remove carbon dioxide?

The respiratory, cardiovascular, and hematologic systems.

Which structures make up the upper respiratory system?

Nose, mouth, pharynx, and larynx.

Name the primary structures of the lower respiratory system.

Trachea, bronchi, bronchioles, lungs, alveoli, pulmonary capillaries, and pleural membranes.

What are the four basic processes necessary for effective gas exchange?

Pulmonary ventilation, alveolar gas exchange, transport of oxygen and carbon dioxide, and systemic diffusion.

Define pulmonary ventilation.

The mechanical movement of air into (inspiration) and out of (expiration) the lungs.

What are the two phases of pulmonary ventilation?

Inspiration (inhalation) and expiration (exhalation).

List five factors required for adequate ventilation.

Clear airways, intact central nervous system, intact thoracic cavity, intact respiratory musculature, and adequate pulmonary compliance/recoil.

Where does an upper airway obstruction occur?

In the nose, pharynx, or larynx.

Where does a lower airway obstruction occur?

Within the bronchi, bronchioles, or lung tissue.

Describe alveolar gas exchange.

Diffusion of oxygen from alveoli into pulmonary capillaries and carbon dioxide from blood into alveoli down their respective pressure gradients.

What is the normal partial pressure of oxygen (PO2) in alveolar air?

About 100 mm Hg.

What is the typical PO2 in venous blood entering the pulmonary capillaries?

About 60 mm Hg.

What is the normal partial pressure of carbon dioxide (PCO2) in venous blood entering pulmonary capillaries?

Approximately 45 mm Hg.

What is the normal PCO2 in alveolar air?

About 40 mm Hg.

How is most oxygen transported in the blood?

Bound loosely to hemoglobin as oxyhemoglobin.

Roughly what percentage of oxygen binds to hemoglobin under normal conditions?

About 97%.

How does decreased cardiac output affect oxygen delivery?

It diminishes the amount of oxygen transported to body tissues.

What effect does a markedly elevated hematocrit have on oxygen transport?

It increases blood viscosity, lowers cardiac output, and reduces oxygen delivery.

How does regular exercise influence oxygen transport?

It boosts cardiac output and cellular oxygen utilization; trained athletes may increase transport up to 20-fold.

Define systemic diffusion in gas exchange.

The diffusion of oxygen and carbon dioxide between tissue capillaries and cells down a concentration gradient.

List six major factors that influence overall oxygenation.

Age, environment, lifestyle, health status, medications, and stress.

During a nursing history, what key respiratory data should be collected?

Past/current respiratory problems, lifestyle, cough, sputum, pain, medications, and risk factors for impaired gas exchange.

Which patient positions promote maximal lung expansion?

Semi-Fowler’s and High-Fowler’s positions.

Why do nurses encourage deep-breathing and coughing exercises?

To promote lung expansion, loosen secretions, and enhance gas exchange.

Define chest physiotherapy (CPT).

A group of techniques (percussion, vibration, postural drainage, etc.) that mobilize and clear airway secretions.

Name three external mechanical maneuvers included in CPT.

Chest percussion, vibration, and postural drainage.

Give four common indications for chest physiotherapy.

Cystic fibrosis, bronchiectasis, atelectasis, lung abscess, or pneumonia with heavy secretions.

List four contraindications to chest physiotherapy.

Increased intracranial pressure, recent spinal injury, active hemorrhage/hemoptysis, or unstable rib fractures/osteoporosis.

Explain the technique of chest percussion.

Using cupped hands to rhythmically strike the chest wall over lung segments to loosen secretions.

Why should cupping never be performed over bare skin or surgical sites?

To prevent tissue damage and pain.

What is the purpose of vibration during CPT?

To further loosen secretions during exhalation so they can be expectorated.

Typically, how long is one lung area percussed during CPT?

About 30–60 seconds (3–5 minutes for very tenacious secretions).

Define postural drainage.

Positioning a patient so gravity aids drainage of secretions from specific lung segments toward the trachea.

Name two conditions where postural drainage is essential therapy.

Bronchiectasis and cystic fibrosis (also severe pneumonia or atelectasis).

Give one major contraindication for postural drainage.

Inability to tolerate the required position (e.g., severe osteoporosis or recent vertebral fracture).

Outline the basic steps of controlled coughing.

Inhale deeply through the nose, pause, then deliver 2–3 sharp coughs with the mouth slightly open, using abdominal muscles.

What water temperature range is recommended for safe steam inhalation?

About 120–160 °F (54–76 °C).

State two therapeutic purposes of steam inhalation.

Relieve airway inflammation/congestion and soften thick mucus to aid expectoration.

For what primary purpose is oropharyngeal suctioning performed?

To clear oral secretions, blood, or vomitus and maintain oral hygiene/airway patency.

During suctioning, how long should negative pressure be applied with each pass?

5–10 seconds, with 20–30-second rest intervals.

Why is a patient hyper-oxygenated before and after suctioning?

To prevent hypoxia caused by suction-related oxygen removal.

What is incentive spirometry (sustained maximal inspiration)?

A technique/device encouraging patients to take slow maximal inspirations held ~3 seconds to prevent atelectasis.

How long should the breath be held during an SMI maneuver?

Approximately 3 seconds (or as instructed, often progressing to 4–5 seconds).

What oxygen concentration range does a nasal cannula deliver?

Roughly 24%–45% at 2–6 L/min.

State the usual flow-rate range and oxygen concentration for a partial rebreather mask.

6–10 L/min delivering about 60%–90% oxygen.

Which face mask can deliver up to 95%–100% oxygen without intubation?

The non-rebreather mask at 10–15 L/min.

Which oxygen delivery device provides precise concentrations of 24%–50%?

The Venturi mask.

Give one key safety precaution regarding smoking for patients on oxygen therapy.

Post “No Smoking—Oxygen in Use” signs and instruct all visitors to smoke only in designated areas away from the patient.

What is the normal arterial oxygen tension (PaO2) range on an ABG?

80–100 mm Hg.

What oxygen saturation (SaO2) range is considered normal on pulse oximetry?

95%–100%.