OXYGENATION STUDY GUIDE

• Roles of the structure/function of the lungs in oxygenation

  1. Respiratory muscles

  2. Pleural space

  3. Lungs and alveoli

  4. Affect 3 processes of oxygenation
• Accessory muscles


  Increase lung volume during inspiration
• Factors affecting lung volume/capacity

  • Amount of surfactant
  • Degree of compliance
  • Strength of respiratory muscles
• Pulmonary circulation


  1. Movement of blood to and from alveolocapillary membrane

  2. Gas exchange occurs
• Respiratory gas exchange occurs in pulmonary capillaries
• Oxygen transport


  Hemoglobin found in red blood cells
• Regulation of respiration/ventilation


  • Complex interplay of neural, chemical, and mechanical factors
  • Ensures adequate oxygen supply and carbon dioxide removal
• Physiological factors affecting oxygenation

  • Oxygen carrying capacity (determined by hemoglobin levels)
  • Oxygen concentration (higher partial pressure facilitates diffusion)
  • Cardiac output (increased enhances oxygen delivery)
  • Blood volume (maintains cardiac output and perfusion)
  • Metabolism (increased demand leads to higher oxygen consumption)
• Conditions affecting chest wall movement

  Impair oxygenation
• Conditions affecting chest wall movement

  • Pregnancy
  • MSK abnormalities
  • Trauma
  • Neuromuscular disease
  • CNS alterations
  • Other chronic diseases
• Causes of hyperventilation


  • Anxiety, infections, drugs or acid-base imbalance
  • Hypoxia associated with pulmonary embolus or shock
  • Fever
  • Chemically induced (salicylate poisoning, amphetamines)
• Causes of hypoventilation


  • Severe atelectasis
  • COPD (inappropriate oxygen administration)
  • Excessive oxygen administration
• Causes of hypoxia


  • Decreased hemoglobin/oxygen-carrying capacity
  • Diminished inspired oxygen concentration
  • Inability of tissues to extract oxygen
  • Decreased diffusion from alveoli
  • Poor tissue perfusion
  • Impaired ventilation
• Causes of cyanosis


  • Peripheral cyanosis (vasoconstriction, stagnant blood flow)
  • Respiratory and cardiovascular conditions (COPD, pneumonia, heart failure, shock)
• Normal respiratory system changes in older adults

  • Trachea and bronchi enlargement
  • Alveoli enlargement, decreasing gas exchange surface area
  • Reduced number of functional cilia, decreased cough mechanism
  • Decreased lung expansion, lowering oxygenation
• Factors affecting respiratory health

  • Poor nutrition
  • Inadequate exercise
  • Smoking
  • Substance abuse
  • Stress
• Dyspnea


  Exaggerated respiratory effort, use of accessory muscles, nasal flaring, increased rate and depth of respirations
• Environmental exposures resulting in lung disease


  • At home: Cigarette smoke, carbon monoxide, radon gas
  • At work: Asbestos, coal, cotton, fibers, fumes, chemicals
  • During travel: Schistosomiasis, Coccidioides immitis
• Respiratory medications requiring monitoring

  • Digitalis preparations, anticoagulants, phenobarbital
• Nursing assessment skills


  1. Inspection: Skin color, appearance, consciousness, circulation, breathing

  2. Palpation: Thoracic excursion, tenderness, abnormal masses

  3. Percussion: Detect abnormal fluid or air

  4. Auscultation: Normal and abnormal heart/lung sounds
• Common nursing diagnoses for respiratory issues


  • Activity intolerance
  • Risk for activity intolerance
  • Ineffective airway clearance
  • Anxiety
  • Ineffective breathing pattern
  • Decreased cardiac output
  • Impaired comfort
• Exercise recommendations for cardiovascular/respiratory health

  1. 4 times per week, 20-30 minutes
• Oxygen as a drug

  Oxygen therapy should be monitored and dosed appropriately to avoid adverse effects like atelectasis or oxygen toxicity
• Safety precautions for oxygen use

  • Oxygen is highly combustible, risk of fire
• Low-flow vs high-flow oxygen devices

  Low-flow: Nasal cannulas, simple masks, provide oxygen with patient's respiratory pattern

  High-flow: Deliver oxygen above normal inspiratory flow, provide fixed FiO2
• Why O2 should be considered a drug

  Oxygen therapy should only be used as indicated and be treated as medication because it has adverse effects, such as atelectasis or oxygen toxicity. The dosage or concentration of oxygen should be monitored to make sure adverse effects won't occur.
• Safety precautions when using O2

  • Oxygen is a highly combustible gas which can easily cause a fire. Patients and healthcare providers must be aware of the dangers of combustion.
• Low-flow O2 devices


  Nasal cannulas, simple face masks, and reservoir masks which provide oxygen in concentrations that carry with the patient's respiratory patterns.
• High-flow O2 devices


  Deliver oxygen rates above the normal inspiratory flow rate and thus provide a fixed FiO2 (fraction of inspired oxygen) regardless of the patient's inspiratory flow and breathing pattern. (eg) Venturi Mask
• Nasal cannula/prongs (NP)


  Low-flow device used for oxygen delivery. Nurses must also be alert for skin breakdown over the ears and in the nares from too tight an application of the nasal cannula.
• Maximum flow rate via NP is up to 6L/minute
• Home O2


  Has a beneficial effect for patients with chronic cardiopulmonary diseases. It improves patients' exercise tolerance and fatigue levels, and in some situations, assists with dyspnea.
• In chronic bronchitis, your airways become swollen and can be filled with mucus, which can make it hard for you to breathe.
• In emphysema, the air sacs (alveoli) in your lungs are damaged which can make it hard for you to breathe.
• Non-respiratory diseases people with COPD are more likely to develop

  • Cardiovascular disease (disease of the heart and circulation)
  • Diabetes and metabolic disease
  • Osteoporosis
  • Anxiety and depression
  • Sleep disorders
  • Anemia
• Common COPD symptoms


  • A cough that lasts a long time (longer than 3 months)
  • A cough with mucus
  • Feeling short of breath
  • Lung infections (the flu, acute bronchitis, pneumonia, etc.) that may last longer than other people you know
  • Wheezing (a whistling sound when you breathe)
  • Feeling tired
  • Losing weight without trying
• Health assessment questions to assist in COPD diagnosis

  • Do you currently smoke? Or did you smoke in the past?
  • How often are you short of breath?
  • What makes your shortness of breath worse?
  • Do you cough? How long have you been coughing?
  • Do you cough up sputum (phlegm, mucus)?
  • Does anyone or did anyone in your family have lung disease?
• Common diagnostic tests for COPD

  • Spirometry test
  • Chest x-ray
  • Oximetry
• Common COPD treatments


  • Taking COPD medications
  • Pulmonary rehabilitation program
  • Lung transplantation
• Types of bronchodilator medications for COPD

  • Beta-2 agonists (e.g. salbutamol, terbutaline, formoterol, salmeterol, indacaterol)
  • Anticholinergics (e.g. ipratropium bromide, tiotropium, glycopyrronium, aclidinium)