oxygenation

Perfusion

The process of delivering oxygenated blood to body tissues through the circulatory system.

Ventilation

The movement of air into and out of the lungs.

Diffusion

The exchange of gases (O₂ and CO₂) between alveoli and capillaries.

Work of Breathing (WOB)

The effort required to expand and contract the lungs during respiration.

Tidal Volume

The amount of air inhaled or exhaled in one normal breath.

Residual Volume

The air remaining in the lungs after full exhalation.

Forced Vital Capacity

The maximum amount of air exhaled forcefully after a full inspiration.

Stroke Volume

The amount of blood pumped by the left ventricle with each contraction.

Cardiac Output

The total volume of blood pumped by the heart per minute (HR × SV).

Preload

The amount of blood in ventricles at the end of diastole (stretch).

Afterload

The resistance the heart must overcome to eject blood.

Hyperventilation

Excessive ventilation leading to low CO₂ levels and respiratory alkalosis.

Hypoventilation

Inadequate ventilation causing CO₂ retention and respiratory acidosis.

Anemia

A decrease in RBCs or hemoglobin, reducing oxygen

Hypovolemia

Decreased circulating blood volume causing tissue hypoxia.

Decreased Inspired Oxygen Concentration

Reduced O₂ in the air (e.g., at high altitudes or from equipment failure).

Increased Metabolic Rate

Causes increased O₂ demand (e.g., fever, pregnancy, exercise).

Impaired Valvular Function

Damaged heart valves that affect blood flow and oxygenation.

Acute Coronary Syndrome

Insufficient blood flow to the heart muscle causing ischemia.

Heart Failure

The heart’s inability to pump enough blood to meet body needs.

Pneumonia

Inflammation of alveoli causing fluid accumulation and impaired gas exchange.

COPD

Chronic obstructive pulmonary disease characterized by airflow limitation.

Infants/Toddlers

Higher risk of upper respiratory infections and airway obstruction.

School

Age/Adolescents

Young/Middle

Aged Adults

Older Adults

Decreased lung elasticity and cilia function; higher infection risk.

Nutrition

Poor diet reduces hemoglobin and oxygen

Hydration

Needed to maintain mucociliary clearance and reduce mucus thickness.

Exercise

Increases oxygen demand and improves cardiac efficiency.

Tobacco Use

Reduces ciliary clearance, causes vasoconstriction, and damages alveoli.

Occupational Exposure

Dust, chemicals, and pollutants impair respiratory function.

History Taking

Collect past medical, social, medication, and allergy history.

Review of Systems (ROS)

Ask about cough, SOB, chest pain, and fatigue.

Skin Inspection

Assess color, cyanosis, and temperature for oxygenation clues.

Level of Consciousness

Hypoxia can cause confusion or restlessness.

Capillary Refill

Should be under 3 seconds; prolonged indicates poor perfusion.

Abnormal Heart Sounds

S3 or S4 may indicate fluid overload or heart failure.

Abnormal Lung Sounds

Crackles, wheezes, or rhonchi indicate airway obstruction or fluid.

Vital Signs

Evaluate RR, HR, BP, temperature, and O₂ saturation for changes.

CBC

Lab test measuring RBC, WBC, and hemoglobin to assess oxygen transport.

Troponin

Cardiac enzyme elevated in myocardial injury.

Lipid Panel

Evaluates cholesterol levels and cardiac risk factors.

Sputum Culture

Identifies infectious organisms in the lungs.

Tuberculin Test

Screens for latent or active tuberculosis infection.

Holter Monitor

Continuous ECG recording to detect arrhythmias.

Stress Test

Evaluates cardiac function under exertion.

ABG

Measures blood oxygen, carbon dioxide, and pH.

Pulmonary Function Tests

Assess lung volumes and airflow.

Bronchoscopy

Visual exam of the airways for obstruction or biopsy.

Lung Scan

Nuclear imaging to detect perfusion or ventilation problems.