Oxygenation

Oxygenation

Chapter 41

Objectives

  • Describe the physiological processes of ventilation, perfusion, and exchange of respiratory gases.

  • Describe the effect of a patient’s level of health, age, lifestyle, and environment on oxygenation.

  • Describe how to assess for the risk factors affecting a patient’s oxygenation.

  • Describe how to assess for the physical manifestations that occur with alterations in oxygenation.

  • Develop a plan of care for a patient with altered oxygenation.

  • Describe nursing care interventions used to promote oxygenation in the primary care, acute care, and restorative and continuing care settings.

  • Describe strategies to use to maintain a patient’s airway.

  • Evaluate a patient’s responses to oxygenation therapies.

Scientific Knowledge Base (1 of 4)
Respiratory Physiology

  • Structure and function:

    • Ventilation: Moves gases into and out of the lungs (comprising inspiration and expiration).

    • Perfusion: The ability of the cardiovascular system to pump oxygenated blood to the tissues and return deoxygenated blood back to the lungs.

    • Diffusion: Moves the respiratory gases from one area to another by concentration gradients.

Scientific Knowledge Base (2 of 4)
Respiratory Physiology Continued

  • Work of Breathing (WOB): Refers to the effort required to breathe and is influenced by:

    • Lung compliance.

    • Airway resistance.

    • Accessory muscles usage.

    • Overall lung volumes: Decreased compliance and increased resistance can lead to increased use of accessory muscles, thereby increasing WOB.

Scientific Knowledge Base (3 of 4)
Pulmonary Circulation

  • Moves blood to and from the capillary membrane for gas exchange (Diffusion).

Respiratory Gas Exchange

  • Oxygen transport:

    • Amount of hemoglobin.

    • Ability of hemoglobin to bind oxygen.

    • Amount of dissolved O₂ in plasma.

Carbon Dioxide Transport

  • Reduced deoxyhemoglobin combines with CO₂ and is expelled back to the lungs and exhaled.

Regulation of Ventilation

  • Neural Regulation: Centrally through the CNS (cerebral cortex).

  • Chemical Regulation: Involves levels of CO₂, O₂, and H⁺ ions.

Scientific Knowledge Base (4 of 4)
Cardiovascular Physiology

  • Structure and Function:

    • Myocardial pump.

    • Myocardial blood flow.

    • Coronary artery circulation.

    • Systemic circulation.

    • Blood flow regulation.

    • Conduction system regulatory mechanisms (e.g. heart rate and rhythm).

Factors Affecting Oxygenation

  • Physiological Factors:

    • Decreased oxygen-carrying capacity: Conditions such as anemia and CO poisoning.

    • Hypovolemia.

    • Decreased inspired oxygen concentration: Such as in lower and upper airway obstructions.

    • High altitudes (with less environmental O₂).

    • Hypoventilation: Causes include opioid use and CNS issues.

    • Increased metabolic rate:

Conditions Affecting Chest Wall Movement

  • Pregnant individuals.

  • Individuals with obesity.

  • Patients with musculoskeletal abnormalities or trauma.

  • Individuals with neuromuscular diseases.

  • Central nervous system alterations and influences of chronic lung diseases.

Developmental Factors Affecting Oxygenation

  • Developmental Stage: Impacts lung expansion and airway clearance, resulting in:

    • Diminished ability to increase ventilation.

    • Declining immune response.

    • Gastroesophageal Reflux Disease (GERD).

Environmental & Lifestyle Factors Affecting Oxygenation

  • Environment:

    • Occupational hazards.

    • Allergies and air quality issues.

  • Lifestyle:

    • Nutrition, hydration, exercise.

    • Smoking and substance abuse.

    • Stress levels.

Alterations in Respiratory Functioning

  • Normal arterial carbon dioxide tension (PaCO₂): 35 ext{ to } 45 ext{ mm Hg}.

  • Normal arterial oxygen tension (PaO₂): 80 ext{ to } 100 ext{ mm Hg}.

  • Hypoventilation: Occurs when alveolar ventilation is inadequate to meet the body's oxygen demand or to remove sufficient carbon dioxide.

  • Hyperventilation: A state where the lungs remove carbon dioxide faster than it is produced by cellular metabolism.

  • Hypoxia: Inadequate tissue oxygenation at the cellular level.

Alterations in Cardiac Functioning

  • Disturbances in conduction.

  • Altered cardiac output: Includes conditions like left-sided heart failure, right-sided heart failure, impaired valvular function, myocardial ischemia, angina, and myocardial infarction.

Left-Sided Heart Failure Symptoms

  • Difficulty breathing: D.

  • Rales/crackles: R, noted at the base of the lungs.

  • Orthopnea: O, inability to breathe unless in an upright position.

  • Weakness: W.

  • Nocturnal paroxysmal dyspnea: N, episodes of severe shortness of breath at night.

  • Increased heart rate: I.

  • Nagging cough: N.

  • Weight gain: G.

Right-Sided Heart Failure Symptoms

  • Swelling in limbs and abdomen: S.

  • Weight gain: W.

  • Edema: E, particularly noted in legs and abdomen.

  • Large neck veins: L, visible upon assessment.

  • Lethargy: L, decreased energy levels.

  • Irregular heartbeat: I.

  • Nausea: N.

  • Increased girth of abdomen: G.

General Signs of Altered Oxygenation

  • Dilated pupils: Indicative of sympathetic nervous system response.

  • Change in skin color: Pale, gray, or cyanotic skin may be observed.

  • Dyspnea: Shortness of breath (SOBOE) early symptom linked to pulmonary congestion.

  • Orthopnea: Difficulty breathing except when sitting upright may occur.

  • Adventitious breath sounds:如 crackles or wheezes.

  • Coughing: May produce frothy pink or white sputum.

  • Decreased blood pressure: Acts as a stimulus to sympathetic nervous system, increasing heart rate and contraction force.

  • Nausea and vomiting: May occur as peristalsis slows and stomach contents backup.

  • Ascites: Fluid accumulation in the peritoneal cavity.

  • Dependent edema: Pitting edema in sacrum or legs.

  • Anxiety: Gasps due to pulmonary congestion.

  • Decreased O2 saturation: Leading to potential confusion or unconsciousness due to decreased oxygen delivery to the brain.

  • Jugular vein distention: Resulting from venous congestion.

  • Fatigue and weakness: From decreased cardiac output.

  • S3 gallop, tachycardia, and enlarged spleen/liver: From venous congestion, causing pressure on breathing.

  • Decreased urine output: As kidneys retain sodium and H₂O in response to decreased cardiac output.

  • Weak pulse: Tied to cardiovascular performance.

  • Cool, moist skin: Resulting from peripheral vasoconstriction redirecting blood flow to vital organs.

Nursing Process: Assessment (1 of 3)
Through the Patient’s Eyes

  • Nursing History: Includes risk assessment for the following:

    • Pain

    • Fatigue

    • Dyspnea

    • Orthopnea

    • Cough

Nursing Process: Assessment (2 of 3)
Nursing History Continued

  • Environmental Exposures: Identifies potential impacts from:

    • Smoking history

    • Respiratory infections

    • Allergies

    • Medications

Medications Affecting Oxygenation

  • Medications Interfering with Pulmonary Function: Certain medications can inhibit respiratory function including:

    • General anesthetics

    • Opioids

    • Anti-anxiety drugs

  • Medications Used to Improve Function:

    • Bronchodilators

    • Anti-inflammatory agents

    • Cough suppressants, expectorants, decongestants

  • Special Considerations: Patients with asthma may have additional management considerations.

Nursing Process: Assessment (3 of 6)
Physical Examination - Inspection

  • Various respiratory patterns such as:

    • Apnea: Absence of respiration lasting 15-20 seconds or longer.

    • Bradypnea: A respiratory rate of less than 12 breaths per minute.

    • Tachypnea: Greater than 20 breaths per minute.

    • Kussmaul breathing: A compensatory deep breathing pattern above 35 breaths per minute.

    • Cheyne-Stokes breathing: An abnormal pattern with alternating periods of apnea and varying depths of breathing.

Physical Examination - Palpation

  • Assess for:

    • Apical pulse and peripheral pulses.

    • Skin temperature, color, and capillary refill.

    • Peripheral edema in feet and legs, as well as assessing pulses in the neck and extremities for adequate blood flow.

  • Pulse Scale: Use a scale from 0 (absent pulse) to 4+ (full, bounding pulse).

Physical Examination - Percussion and Auscultation

  • Percussion: To detect abnormal fluid or air presence in the lungs.

  • Auscultation: To listen for:

    • S1 and S2 heart sounds.

    • Additional heart sounds (e.g. murmurs).

    • Adventitious breath sounds (e.g. wheezes, crackles, rhonchi).

Assessment - Physical Exam Continued
Breathing Patterns and Efforts

  • Observe for:

    • Nasal flaring or retractions.

    • Accessory muscle usage.

    • Grunting during breathing.

    • Body positioning indicators.

    • Paroxysmal Nocturnal Dyspnea: Episodes of shortness of breath at night.

    • Conversational Dyspnea: Breathing difficulties when speaking.

    • Presence of stridor or wheezing.

    • Diminished or absent breath sounds.

Nursing Diagnosis

  • Examples of Nursing Diagnoses for patients exhibiting alterations in oxygenation:

    • Impaired Cardiac Output

    • Acute Pain

    • Activity Intolerance

    • Risk for Activity Intolerance

    • Impaired Airway Clearance

Planning

  • Utilize critical thinking skills to synthesize information from diverse sources during planning.

  • Establish Goals and Outcomes that are:

    • Realistic.

    • Measurable.

  • Prioritize care based on the assessed needs.

  • Emphasize Teamwork and Collaboration.

Implementation: Health Promotion

  • Vaccinations: Ensure influenza and pneumococcal vaccines are administered.

  • Healthy Lifestyle:

    • Eliminating risk factors.

    • Eating a balanced diet.

    • Engaging in regular physical exercise.

  • Environmental Precautions: Identify and mitigate exposure to pollutants such as secondhand smoke and industrial chemicals.

Implementation: Acute Care (1 of 6)
Dyspnea Management

  • Airway Maintenance: Ensuring patency through various methods.

  • Mobilization of Pulmonary Secretions: Techniques include:

    • Hydration

    • Humidification

    • Nebulization

    • Coughing and deep-breathing practices.

    • Review specific techniques such as Huff cough and quad cough techniques.

Implementation: Acute Care (2 of 6)
Chest Physiotherapy

  • Techniques include external manipulation of the chest wall via:

    • Percussion

    • Vibration

    • High-frequency chest wall compression (HFCWC)

    • Postural Drainage: Utilizes body positioning to aid drainage.

Implementation: Acute Care (3 of 6)
Maintenance and Promotion of Lung Expansion

  • Techniques include:

    • Ambulation

    • Proper positioning

    • Use of Incentive Spirometry

    • Consider an acapella device for lung expansion.

Implementation: Acute Care (4 of 6)
Suctioning Techniques

  • Different types include:

    • Oropharyngeal and Nasopharyngeal suctioning.

    • Orotracheal and Nasotracheal suctioning.

    • Tracheal suctioning.

Implementation: Acute Care (5 of 6)
Suctioning Airways

  • Goal: Removal of excess secretions to maintain airway patency.

  • Assess for:

    • Gurgling sounds.

    • Adventitious breath sounds.

    • Signs of labored breathing.

  • Personnel Authorized: Registered Nurses (RN), Licensed Practical Nurses (LPN), and Respiratory Therapists (RT) can perform suctioning.

Implementation: Acute Care (6 of 6)
Artificial Airways

  • Types of artificial airways include:

    • Oropharyngeal Airway: Used to prevent airway obstruction.

    • Nasopharyngeal Airway: Used for patients requiring airway assistance.

Endotracheal and Tracheal Airways

  • Airway management may involve:

    • Endotracheal Tubes: Inserted through the mouth or nose into the trachea.

    • Tracheostomy Tubes: For prolonged ventilation needs.

Invasive Mechanical Ventilation

  • Essential in severe respiratory distress.

  • Continuous Positive Airway Pressure (CPAP) and Bilevel Positive Airway Pressure (BiPAP):

    • BiPAP: Provides two pressure settings, beneficial for complex respiratory issues.

Chest Tubes

  • Hemothorax: Accumulation of blood and fluid in pleural space.

  • Pneumothorax: Accumulation of air leading to lung collapse.

  • Purpose: Chest tubes remove excess air and fluid to allow lung re-expansion.

Chest Tube Care

  • Hemothorax and Pneumothorax Management: Involves the systematic removal of air or fluid via a drainage system.

  • Setup Considerations: Chest tube systems must be sealed and maintained for functionality.

Chest Tube: Special Considerations

  • Proper management of drainage systems is crucial to avoid complications. Regular monitoring and troubleshooting of the setup is required.

Sample Patient Case

  • Case Study: Recorded observations show measures taken, response to suctioning, and vital signs post-procedure.

  • Documentation includes detailed assessments of respiratory function improvements post-intervention.

Unexpected Events

  • Management of Disconnected/Dislodged Chest Tubes:

    • Check connections and reattach using sterile techniques.

    • Immediately apply pressure at the insertion site and obtain a sterile petroleum gauze dressing.

    • Notify healthcare provider promptly.

Implementation: Acute Care Continued
Maintenance and Promotion of Oxygenation

  • Safety Precautions for Oxygen Therapy:

    • Awareness of oxygen toxicity and risks associated with pressurized oxygen tanks.

    • Always require an order to adjust oxygen concentration.

Oxygen Delivery Devices

  • Low-flow devices:

    • Nasal Cannula: Delivering 1-6 L/min (24-44% FiO₂).

    • Simple Face Mask: Minimum rate of 6-12 L/min (35-50% FiO₂).

  • High-flow devices:

    • Venturi Mask: Provides accurately controlled oxygen delivery of specific concentrations.

Important Notes on Different Masks

  • Rebreather Masks: Used in moderate hypoxemia, delivering 60-90% FiO₂ at 6-11 L/min.

  • Non-Rebreather Masks: For severe hypoxemia, can deliver high concentration (80-95% FiO₂) at 10-15 L/min, requiring a snug fit.

Emergency Response

  • Code Blue Protocols: Immediate response for cardiac or respiratory arrest, including chest compressions and airway management protocols.

Restorative and Continuing Care

  • Involves respiratory muscle training, breathing exercises (e.g., pursed-lip and diaphragmatic breathing), and home-based oxygen therapy.

Evaluation
Through Patient's Eyes

  • Evaluate how the disease impacts daily life and the patient’s perceived response to treatment outcomes.

  • Compare actual patient progress against defined care goals to assess ongoing health status.

Safety Guidelines in Nursing Practice

  • Recognize baseline vital signs for each patient.

  • Limit catheter introduction to two instances per suctioning session.

  • Prioritize tracheal suctioning before pharyngeal suctioning.

  • Caution advised when suctioning head-injured patients.

  • Review institutional policies regarding chest tube management and suctioning guidelines.