Oxygenation Fundamentals

Oxygenation

Introduction

  • Oxygenation is essential for survival and encompasses various processes that ensure oxygen is available to cells throughout the body.

  • Common misconception: "LOVE IS IN THE AIR?" FALSE. The primary components of air are nitrogen, oxygen, argon, and carbon dioxide.

Objectives of Oxygenation

  1. Identify risk factors for alterations in oxygenation

  2. Discuss elements of focused respiratory assessment identifying abnormal findings

  3. Interpret lab and diagnostic findings related to alterations in oxygenation

  4. Distinguish the uses of different oxygen delivery methods

  5. Apply safety principles to oxygen administration

  6. Implement nursing interventions for clients with alterations in oxygenation

  7. Evaluate the effectiveness of nursing care provided to clients with oxygenation alterations

Nursing Process in Oxygenation

  1. Assessment: Objectives 1-3

  2. Diagnosis: Objectives 2-3

  3. Planning: Objective 7

  4. Implementation: Objectives 4-6

  5. Evaluation: Objective 7

Respiratory Physiology

  • Primary functions:

    • Brings oxygen into the body and removes carbon dioxide.

    • Helps maintain the body’s acid-base balance.

  • Gas exchange locations:

    • External respiration: Occurs in the lungs (O₂ in, CO₂ out)

    • Internal respiration: Occurs in body tissues (O₂ to cells, CO₂ back to blood)

  • Ensures cells are supplied with oxygen while removing waste gases.

Key Processes Required for Oxygenation

  • Ventilation: The movement of air in and out of the lungs.

  • Perfusion: Blood flow through pulmonary capillaries.

  • Diffusion: Movement of O₂ and CO₂ across the alveolar-capillary membrane.

  • Oxygen Transport: Hemoglobin carries oxygen through the bloodstream to body tissues.

Work of Breathing (WOB)

  • Definition: Refers to how hard the body has to work to breathe.

  • Healthy Breathing: Should be quiet and require minimal effort.

  • WOB increases when:

    • Airway resistance increases

    • Lung compliance decreases

    • Rate or depth of breathing increases

  • Signs of increased WOB:

    • Use of accessory muscles

    • Nasal flaring

    • Retractions

    • Tachypnea

Alterations in Respiratory Functioning

  • Hypoventilation:

    • Condition where not enough air is exchanged, leading to CO₂ retention.

    • Causes: Opioids, sedatives, neuromuscular problems, respiratory muscle fatigue.

  • Hyperventilation:

    • Condition characterized by fast or deep breathing leading to excessive CO₂ removal.

    • Causes: Anxiety, pain, fever, early respiratory distress.

  • Hypoxia: Tissues not receiving enough oxygen. Symptoms include restlessness, anxiety, tachypnea, and late signs such as inability to speak in full sentences and decreasing SpO₂.

Cardiovascular Physiology

  • Heart Function: Pumps blood throughout the body.

  • Blood Function: Carries oxygen and nutrients to tissues while removing CO₂ and waste.

Risk Factors Affecting Oxygenation

  • Physiological Factors:

    • Decreased oxygen-carrying capacity

    • Hypovolemia

    • Decreased inspired oxygen concentration

    • Increased metabolic rate

    • Conditions affecting chest wall movement

  • Lifestyle Factors:

    • Poor nutrition, dehydration, lack of exercise, smoking, substance abuse, stress.

  • Developmental Factors:

    • Infants and toddlers

    • School-age children and adolescents

    • Young and middle-aged adults

    • Older adults

  • Environmental Factors:

    • Air pollution, secondhand smoke, occupational exposures.

Health History in Respiratory Assessment

  • Important inquiries include:

    • Health risks such as family history of lung cancer or cardiovascular disease.

    • Common respiratory symptoms: dyspnea, cough, sputum production, chest pain, wheezing, fatigue.

    • Past respiratory conditions: asthma, COPD, pneumonia, allergies, respiratory infections.

    • Lifestyle factors: smoking or vaping, occupational exposures.

    • Medications like bronchodilators, steroids, and opioids.

Normal Adult Values

  • Respiratory Rate (RR): 12-20 breaths/min

  • Oxygen Saturation (SpO₂): 95–100%

  • End-tidal CO₂: 35-45 mmHg

Pulse Oximetry (SpO2)

  • Measures how much oxygen is attached to hemoglobin in the blood.

  • Noninvasive method with a normal adult range of 95–100%.

  • COPD goal: 88–92%.

  • Limitations:

    • Inaccuracy in cold fingers or poor circulation, and in patients with anemia.

Capnography

  • Definition: Measures the amount of carbon dioxide in exhaled air.

  • Reflects how well a patient is ventilating. Normal range: 35 - 45 mmHg.

Inspection During Respiratory Assessment

  • Look for:

    • Skin and mucous membrane color

    • Level of conscious (LOC)

    • Breathing patterns

    • Chest wall movement

    • Clubbing of nails

    • Shape of chest

Palpation and Percussion

  • Palpation:

    • Assess chest expansion, tenderness, abnormalities, peripheral pulses, skin temperature, cap refill, and edema.

  • Percussion:

    • Tapping of the chest to identify abnormal fluid, air, or solid tissue in the lungs.

Adventitious Lung Sounds

  1. Wheezes:

    • Sound: High-pitched musical sound during inspiration, expiration, or both.

    • Pathophysiology: Result from narrowed airways due to inflammation or bronchospasm.

    • Common Diseases: Asthma, acute bronchitis, pneumonia.

  2. Crackles:

    • Sound: Crackling/popping, usually heard during inspiration.

    • Fine crackles correspond to smaller airways, while coarse crackles correspond to larger airways.

    • Pathophysiology: Air moves through fluid or secretions in airways/alveoli.

    • Common Diseases: Pneumonia, emphysema, chronic bronchitis, pulmonary edema, heart failure.

  3. Rhonchi:

    • Sound: Low-pitched, snoring or rumbling noise often heard during expiration.

    • Pathophysiology: Caused by thick mucus or muscle spasms in the airways.

    • Common Diseases: Asthma, pneumonia, chronic bronchitis, cystic fibrosis.

Diagnostic Tests for Oxygenation Problems

  • Chest X-Ray:

    • Quick and painless imaging of lungs and heart.

    • Useful for detecting pneumonia, fluid, collapsed lung, heart failure.

    • Not recommended during pregnancy.

  • Sputum Culture:

    • Tests mucus for bacteria or infection.

    • Collected via patient coughing into a sterile cup.

    • Helps to select appropriate antibiotics.

  • Arterial Blood Gas (ABG):

    • Measures oxygen, carbon dioxide, and pH in arterial blood.

    • Indicated for patients in respiratory distress or instability.

Early Signs of Oxygenation Alterations

  • Restlessness

  • Anxiety

  • Tachypnea (RR > 20)

  • Increased WOB

  • Difficulty speaking in full sentences

  • Decreasing SpO₂

Late Signs of Oxygenation Alterations

  • Cyanosis

  • Bradycardia

  • Severe dyspnea

  • Decreased level of consciousness (LOC)

  • Lethargy or drowsiness

  • Respiratory fatigue

  • SpO₂ < 88%

Case Study: Mr. Homer Simpson

  • Patient Details:

    • 49-year-old with shortness of breath, fever, productive cough lasting four days.

    • Reports a sensation of heaviness in the chest; persistent cough.

  • Medical History:

    • Hypertension, obesity, smoker (1 pack/day), drinks 3-4 beers nightly, works sedentarily.

  • Assessment Findings:

    • Temp: 101.8°F (38.8°C)

    • RR: 28/min, labored

    • SpO₂: 86% on room air

    • HR: 110 bpm

    • BP: 138/88 mmHg

    • Pale, diaphoretic skin, and lung sounds featuring crackles and diminished breath sounds in the right lower lobe.

    • Productive cough with thick yellow sputum.

Diagnosis

  • Impaired gas exchange:

    • Low PaO₂ or high CO₂ in ABG, SpO₂ < 90%, confusion, cyanosis.

  • Ineffective airway clearance:

    • Weak or absent cough, thick sputum, rhonchi, ineffective cough.

  • Ineffective breathing pattern:

    • Abnormal breathing rate, accessories muscle use.

  • Decreased cardiac output:

    • Fatigue, low BP, low O₂ saturation, weak pulses, pallor.

  • Activity intolerance:

    • Symptoms upon exertion encountered.

  • Anxiety:

    • Impedes normal breathing.

  • Risk for aspiration:

    • Weak cough, dysphagia issues.

  • Risk for infection due to retained secretions.

Nursing Diagnoses

  1. Impaired gas exchange related to inflammation of alveoli.

  2. Ineffective airway clearance related to increased mucus production.

  3. Activity intolerance related to imbalance between oxygen supply and demand.

Planning in Nursing

  • Use assessment findings to guide care.

  • Set SMART goals focused on improving oxygenation.

  • Collaborate with the healthcare team (e.g., respiratory therapy, dietitians).

Planning Goals

  • Broad Goal: Client will maintain adequate oxygenation and improve ventilation.

  • SMART Outcomes:

    • Homer’s SpO₂ will remain ≥ 92% on 2 L/min nasal cannula within 4 hours.

    • RR will decrease to 20-24/min by end of shift.

    • Homer will demonstrate effective coughing technique by the next nursing shift.

    • Homer will report dyspnea ≤ 3/10 at rest within 8 hours.

Nursing Interventions

  • Position patient in High Fowler’s to promote lung expansion.

  • Apply 2 L/min oxygen via nasal cannula as ordered.

  • Administer prescribed antibiotics for infection.

  • Encourage deep breathing, coughing, and incentive spirometer use every 1–2 hours to prevent atelectasis.

  • Administer bronchodilator as prescribed to open airways.

  • Encourage fluid intake (2–3 L/day if not contraindicated) to thin secretions.

  • Schedule rest periods between activities.

  • Administer antipyretics (such as acetaminophen) for fever control.

  • Include teachings on smoking cessation and infection prevention prior to discharge.

Evaluating Nursing Care

  • Patient reports:

    • Effectiveness of interventions aiding breathing.

  • Cough frequency and sputum production: Monitoring improvement.

  • Lung sounds: Noting changes in adventitious sounds (e.g., crackles).

  • Diagnostic tests: Perform ABGs, chest X-ray, sputum culture as necessary.

  • Breathing assessment: Observe for degree of shortness of breath and use of accessory muscles.

  • Oxygen status monitoring: Regular pulse oximetry checks before, during, and after various activities.

  • Patient symptoms: Ascertain their level of fatigue and breathlessness ratings on a scale from 0-10.

Evaluation of Goals and Outcomes

  • Follow-Up Findings:

    • SpO₂ improved to 94% on 2 L nasal cannula.

    • RR decreased to 20/min.

    • HR stabilized at 88 bpm.

    • Patient verbalizes improved ability to take deep breaths.

    • Reduction in crackles; sputum thinner and clearer.

    • Temperature trending downward to 99.5°F, indicating improvement.

Conclusion

  • The holistic approach in assessing, diagnosing, planning, implementing, and evaluating the care of patients with oxygenation issues is critical for effective nursing practice.