Fundamentals of Nursing: Oxygenation

Scientific Knowledge Base

Respiratory Physiology

• Structure and Function: Fundamental understanding of the respiratory system.

• Work of Breathing: The effort required for inhalation and exhalation.

• Lung Volumes: Different capacities and volumes of air that can be inhaled or exhaled by the lungs.

• Pulmonary Circulation: Blood flow through the lungs for gas exchange.

Respiratory Gas Exchange

• Oxygen Transport: Mechanisms by which oxygen is carried from the lungs to the body tissues.

• Carbon Dioxide Transport: Mechanisms by which carbon dioxide is carried from the body tissues to the lungs for exhalation.

• Regulation of Ventilation: Control mechanisms that adjust the rate and depth of breathing.

Cardiovascular Physiology

• Structure and Function: Understanding of the heart and blood vessels.

• Myocardial Pump: The heart's ability to effectively pump blood.

• Myocardial Blood Flow: The circulation of blood through the coronary arteries to supply the heart muscle.

• Coronary Artery Circulation: Specific emphasis on the blood supply to the heart.

• Systemic Circulation: Blood flow throughout the rest of the body.

• Blood Flow Regulation: Mechanisms that control and adjust blood distribution and pressure.

• Conduction System: The electrical system of the heart that initiated and regulates heartbeats.

Factors Affecting Oxygenation: Physiological Factors

• Decreased Oxygen-Carrying Capacity: Conditions that reduce the blood's ability to carry oxygen (e.g., anemia).

• Hypovolemia: A decrease in circulating blood volume, leading to reduced tissue perfusion.

• Decreased Inspired Oxygen Concentration: Lower than normal oxygen levels in the air breathed in (e.g., high altitudes, obstructed airways).

• Increased Metabolic Rate: Conditions that increase the body's demand for oxygen (e.g., fever, exercise, sepsis).

• Conditions Affecting Chest Wall Movement: Factors that impair the mechanical process of breathing:

  • Pregnancy: The growing uterus can push on the diaphragm.

  • Obesity: Excessive weight can restrict chest wall movement.

  • Musculoskeletal Abnormalities: Conditions like kyphoscoliosis that restrict chest expansion.

  • Trauma: Rib fractures, flail chest, or pneumothorax.

  • Neuromuscular Diseases: Conditions like myasthenia gravis, Guillain-Barré syndrome, or ALS that weaken respiratory muscles.

  • Central Nervous System Alterations: Brain injuries, spinal cord injuries, or drug overdoses affecting respiratory drive.

  • Influences of Chronic Lung Disease: Conditions like COPD or asthma that structurally alter the lungs and chest wall.

Alterations in Respiratory Functioning

• Hypoventilation: Inadequate ventilation to meet the body's oxygen demand or to eliminate carbon dioxide, leading to hypercapnia and hypoxemia.

• Hyperventilation: Ventilation in excess of that required to eliminate carbon dioxide produced by cellular metabolism, potentially leading to hypocapnia.

• Hypoxia: Inadequate tissue oxygenation at the cellular level.

Alterations in Cardiac Functioning

• Disturbances in Conduction: Irregularities in the heart's electrical system (e.g., arrhythmias, heart blocks).

• Altered Cardiac Output: The heart's inability to pump adequate blood to meet metabolic demands, including:

  • Left-Sided Heart Failure: Failure of the left ventricle, leading to pulmonary congestion.

  • Right-Sided Heart Failure: Failure of the right ventricle, leading to systemic congestion.

• Impaired Valvular Function: Stenosis or insufficiency of heart valves, affecting blood flow.

• Myocardial Ischemia: Insufficient blood supply to the heart muscle, leading to:

  • Angina: Chest pain caused by temporary myocardial ischemia.

  • Myocardial Infarction: Permanent damage to the heart muscle due to prolonged ischemia (heart attack).

Nursing Knowledge Base

Factors Influencing Oxygenation

• Developmental Factors: How oxygenation needs and vulnerabilities change across the lifespan:

  • Infants and Toddlers: Immature respiratory systems, higher risk for respiratory infections.

  • School-Age Children and Adolescents: Developing respiratory systems, increased exposure to pathogens.

  • Young and Middle-Age Adults: Generally healthy, but lifestyle choices begin to impact.

  • Older Adults: Decreased lung elasticity, weakened respiratory muscles, reduced immune response.

• Lifestyle Factors: Personal choices and habits affecting respiratory and cardiovascular health:

  • Nutrition: Adequate nutrition supports respiratory muscle function and immune health.

  • Hydration: Maintains moist mucous membranes and liquefies secretions for easier clearance.

  • Exercise: Regular physical activity strengthens cardiovascular and respiratory systems.

  • Smoking: Major risk factor for COPD, lung cancer, and cardiovascular disease.

  • Substance Abuse: Depresses respiratory drive, increases aspiration risk, and impairs cardiac function.

  • Stress: Can increase metabolic rate and oxygen demand, leading to shallow breathing or hyperventilation.

• Environmental Factors: External elements that can impact oxygenation:

  • Occupational pollutants (e.g., asbestos, chemical fumes).

  • Air quality (e.g., smog, allergens).

  • Altitude (lower oxygen concentration at high altitudes).

Critical Thinking in Oxygenation

Critical thinking provides a scientific, methodical, and logical approach to patient care, supported by various foundational elements.

Knowledge Base

• Cardiopulmonary Anatomy and Physiology: Basic understanding of structure and function.

• Cardiopulmonary Pathophysiology: Understanding disease processes affecting these systems.

• Physiological Factors Affecting Oxygenation: As described previously (decreased O2 capacity, hypovolemia, etc.).

• Pharmacological Factors Affecting Oxygenation: How medications impact respiratory and cardiac function.

• Environmental Factors Affecting Oxygenation: External influences on respiratory health.

• Developmental Factors Affecting Oxygenation: Age-related changes and risks.

• Risk Factors for Impaired Oxygenation: Identifying predispositions to oxygenation problems.

• Signs and Symptoms of Impaired Oxygenation: Recognizing clinical manifestations.

• Effects of Patient's Illness or Disability on Oxygenation and Energy Needs: Understanding the holistic impact of conditions.

Attitudes

• Confidence: Displaying confidence when assessing the extent of a patient's cardiopulmonary alterations.

• Creativity: Using creativity when assessing cultural factors influencing a patient's risk factors and care needs.

Professional Standards

• ANA (American Nurses Association) Standards and Scope of Nursing Practice: Guidelines for professional nursing conduct.

• Clinical Practice Guidelines and Standards of Practice: Evidence-based recommendations for specific conditions.

• Intellectual Standards in Measurement: Ensuring accuracy and precision in data collection and interpretation.

• Agency Policies and Procedures: Institution-specific rules for care delivery.

• Professional Standards of Care: Guidelines from professional organizations (e.g., American Cancer Society, American Heart Association, American Association for Respiratory Care).

• Ethical Standards: Moral principles guiding nursing decisions.

Environment

• Medical Devices: Presence of devices that may impact the time and complexity of care.

• Available Resources or Equipment: Identifying resources to improve patient oxygenation.

• Need for Additional Necessary Personnel: Determining when other healthcare team members are required.

Experience

• Experience Caring for Patients with Cardiopulmonary Conditions: Practical application of knowledge.

• Experience Observing Patient Responses to Oxygen Therapies: Learning from previous patient outcomes.

• Personal Experiences with Cardiopulmonary Alterations: Understanding from one's own or observed health challenges (e.g., respiratory infections, heart disease).

Clinical Decision Making (Integrating Critical Thinking into the Nursing Process)

• Recognize Cues: Initial observation and data gathering.

• Analyze Cues: Interpreting and grouping collected data.

• Prioritize Hypotheses: Determining the most pressing patient problems.

• Generate Solutions: Developing potential interventions.

• Take Action (Implementation): Carrying out planned interventions.

• Evaluate Outcomes (Evaluation): Assessing the effectiveness of interventions.

Nursing Process

Assessment

• Through the Patient's Eyes: Understanding the patient's subjective experience of oxygenation status.

• Nursing History: Comprehensive questioning to gather relevant information:

  • Health Risks: Identifying predisposing factors for impaired oxygenation.

  • Pain: Chest pain, pleuritic pain, or pain interfering with breathing.

  • Fatigue: A common symptom of inadequate oxygenation.

  • Dyspnea: Subjective sensation of shortness of breath.

  • Cough: Characteristics (productive/non-productive, quality, timing).

  • Environmental and Occupational Factors: Exposure to pollutants, allergens, or irritants.

  • Smoking: History, frequency, and duration of smoking habits.

  • Respiratory Infections: Frequent or recurrent infections.

  • Allergies: Environmental or medication allergies that affect respiration.

  • Medications: Current medications, including bronchodilators, steroids, or cardiac drugs.

• Physical Examination: Systematic examination of the respiratory and cardiovascular systems:

  • Inspection: Observing respiratory rate, rhythm, effort, chest symmetry, skin color.

  • Palpation: Assessment of chest expansion, fremitus, and pulses.

  • Percussion: Tapping on the chest to assess lung density and fluid.

  • Auscultation: Listening to lung sounds (e.g., crackles, wheezes, diminished) and heart sounds.

• Diagnostic Tests: Ordering and interpreting objective data:

  • Chest X-rays, CT scans, MRIs.

  • Pulmonary function tests (PFTs).

  • Arterial blood gases (ABGs).

  • Sputum cultures.

  • Electrocardiogram (ECG).

  • Blood tests (e.g., CBC, cardiac enzymes).

Analysis and Nursing Diagnosis

Based on assessment data, formulating nursing diagnoses. Examples include:

• Impaired Cardiac Output

• Acute Pain

• Activity Intolerance

• Fatigue

• Impaired Airway Clearance

Planning and Outcomes Identification

Developing a plan of care with specific patient-centered goals.

• Outcomes: Measurable, realistic goals for the patient's oxygenation status.

• Setting Priorities: Determining which problems require immediate attention.

• Teamwork and Collaboration: Working with other healthcare professionals (e.g., respiratory therapists, physicians, physical therapists) to optimize care.

Implementation

Performing the planned nursing interventions to promote oxygenation.

• Knowledge Base for Implementation: Knowledge of effective interventions, signs/symptoms of impaired oxygenation, delegation principles, and patient assessment/diagnoses.

• Attitudes for Implementation: Confidence in applying interventions, responsibility for safe use of oxygen delivery systems and airway management devices.

• Environment for Implementation: Determining when other healthcare personnel are needed (e.g., assistive personnel for artificial airway care), avoiding unnecessary interruptions by timing therapies.

• Standards for Implementation: Adherence to ANA standards, clinical practice guidelines, intellectual standards, agency policies, professional standards of care, and ethical standards.

• Experience for Implementation: Previous experience caring for patients with impaired oxygenation, using oxygen-delivery interventions, maintaining patent airways, artificial airway care, chest tubes, and teaching patients/families about home oxygenation.

Health Promotion

• Vaccinations: Influenza, pneumococcal vaccines to prevent respiratory infections.

• Healthy Lifestyle: Promoting balanced nutrition, regular exercise, and stress management.

• Environmental Pollutants: Educating on avoidance of smoke, allergens, and occupational hazards.

Acute Care Interventions

• Dyspnea Management: Strategies to relieve shortness of breath (e.g., positioning, relaxation techniques).

• Airway Maintenance: Keeping the airway clear and open.

• Mobilization of Pulmonary Secretions: Techniques to help patients clear mucus:

  • Hydration: Adequate fluid intake to thin secretions.

  • Humidification: Adding moisture to inspired air to prevent drying of mucous membranes.

  • Nebulization: Delivering medicated aerosols to open airways or loosen secretions.

  • Coughing and Deep-Breathing Techniques: Encouraging effective coughing and maximal lung inflation.

  • Chest Physiotherapy: Percussion, vibration, and postural drainage to loosen and clear secretions.

  • Positive Expiratory Pressure (PEP): Devices that provide resistance during exhalation to help move secretions.

• Maintenance and Promotion of Lung Expansion: Strategies to ensure full lung inflation:

  • Ambulation: Encouraging movement to prevent atelectasis and promote secretion clearance.

  • Positioning: Using various positions (e.g., Fowler's, prone) to optimize lung expansion and drainage.

  • Incentive Spirometry: Device used to encourage deep breathing and prevent atelectasis.

• Maintenance of Patent Airway: Specific interventions for airway control:

  • Artificial Airways: Endotracheal tubes, tracheostomy tubes to secure an airway.

  • Open and Closed Airway Suctioning: Removal of secretions from the airway.

  • Suctioning Techniques: Proper methods to ensure effective and safe secretion removal.

• Maintenance of Ventilation: Supporting the breathing process:

  • Invasive Mechanical Ventilation: Use of a ventilator with an artificial airway for respiratory support.

  • Noninvasive Ventilation: BiPAP, CPAP to assist breathing without an artificial airway.

  • Chest Tubes: Drains inserted into the pleural space to remove air or fluid.

  • Special Considerations (Indwelling Tunneled Pleural Catheter (Pleur X)): A long-term catheter for recurrent pleural effusions.

• Maintenance and Promotion of Oxygenation: Direct administration of oxygen:

  • Oxygen Therapy: Supplemental oxygen delivery via nasal cannula, mask, etc.

• Restoration of Cardiopulmonary Functioning: Interventions specifically aimed at rehabilitating the heart and lungs.

Restorative and Continuing Care

• Respiratory Muscle Training: Exercises to strengthen the diaphragm and intercostal muscles.

• Breathing Exercises: Targeted techniques to improve breathing efficiency:

  • Pursed-Lip Breathing: Slows exhalation, prevents airway collapse, and improves gas exchange.

  • Diaphragmatic Breathing: Encourages the use of the diaphragm for deeper, more efficient breaths.

• Home Oxygen Therapy: Education and management for patients requiring long-term oxygen at home.

Evaluation

Assessing the effectiveness of nursing care in achieving patient outcomes.

• Through the Patient's Eyes: Patient's subjective report of symptom relief and improvement.

• Patient Outcomes: Objective measurement of whether planned goals were met.

• Knowledge Base for Evaluation: Understanding pathophysiological/pharmacological factors affecting oxygenation, characteristics of adequate oxygenation status, patient expectations, and current assessment findings.

• Attitudes for Evaluation: Confidence in evaluating outcomes, responsibility for safely evaluating oxygen-delivery systems and airway management devices, and responsibility for thorough examination of oxygenation status.

• Environment for Evaluation: Identifying modifiable environmental factors to improve time management/task complexity, observing patient's use of adaptive equipment, and determining the effectiveness of healthcare resources.

• Standards for Evaluation: Adherence to ANA standards, clinical practice guidelines, intellectual standards, agency policies, professional standards of care, and ethical standards.

• Experience for Evaluation: Clinical experience caring for patients with impaired oxygenation, skill competence with devices/procedures, and prior experience evaluating learning outcomes about home oxygenation.

Safety Guidelines

• Know a Patient's Baseline Range of Vital Signs: Essential for recognizing deviations and assessing changes in oxygenation.

• Know a Patient's Medical History: Provides context for current status and potential risks.

• Identify Conditions that Increase a Patient's Risk for Aspiration: Preventing gastric contents from entering the lungs is critical to avoid airway obstruction or pneumonia.

• Identify Patients at Risk for Problems Due to Suctioning: Be aware of conditions such as trauma to the upper or lower airway, nasal polyps, coagulopathies, recent head and neck surgery, or hemodynamic instability, which contraindicate or require caution with suctioning.

• Artificial Airways Alter Communication: Recognize that these devices can cause feelings of fear, frustration, anxiety, and vulnerability in patients, and provide alternative communication methods.

• Oropharyngeal Suctioning with a Yankauer Catheter Tip: Can be performed using a clean technique.

• Nasopharyngeal, Nasotracheal, and Artificial Airway Suctioning: Must be done using aseptic technique.

• Tracheal vs. Oropharyngeal Suctioning: Perform tracheal suctioning before oropharyngeal suctioning whenever possible to prevent contamination. If abundant oral secretions are present, suction the mouth with a separate oral suction device first.

• Suctioning in Head Injury Patients: Use caution to reduce the risk of intracranial pressure (ICP). Preoxygenate the patient before suctioning, which results in hypocarbia and may help reduce ICP.

• Normal Saline Instillation (NSI) Before Suctioning: The routine use of NSI into the airway before endotracheal and tracheostomy suctioning is not recommended (AARC, 2022). It is associated with adverse effects such as excessive coughing, bronchospasm, spread of organisms to the lower respiratory tract, and decreased oxygen saturation. NSI may be indicated in certain circumstances to stimulate a cough, but this requires collaboration with the healthcare team.

• Tracheostomy Complication: The most serious complication is airway obstruction, which can lead to cardiac arrest. Always ensure a spare inner tube/cannula is at the bedside for emergency replacement, as most tracheostomy tubes have one that can be removed and replaced if occluded.

• Chest Tubes: Review agency policy before stripping or milking chest tubes, as these actions can generate excessively high or low pressures within the pleural cavity, potentially causing harm.