👩‍⚕️Foundations of Nursing Practice Unit 16 – Oxygenation and Respiratory Care

Key Concepts in Respiratory Physiology

• Respiration involves gas exchange between the lungs and the bloodstream, delivering oxygen to cells and removing carbon dioxide
• The respiratory system consists of the airways (nose, pharynx, larynx, trachea, bronchi, and bronchioles) and the lungs (alveoli)
• Ventilation is the process of moving air in and out of the lungs, which is controlled by the diaphragm and intercostal muscles
  • Inspiration (inhalation) occurs when the diaphragm contracts and the intercostal muscles lift the ribs, increasing the volume of the thoracic cavity
  • Expiration (exhalation) is typically passive, as the diaphragm relaxes and the elastic recoil of the lungs and chest wall decreases the volume of the thoracic cavity
• Diffusion is the passive movement of gases between the alveoli and the bloodstream, driven by concentration gradients
• Perfusion refers to the blood flow through the pulmonary capillaries, which is essential for effective gas exchange
• Ventilation-perfusion (V/Q) matching ensures that well-ventilated alveoli receive adequate blood flow for optimal gas exchange
• Oxygen is transported in the blood by binding to hemoglobin in red blood cells (97%) and dissolved in plasma (3%)

Assessing Respiratory Function

• Respiratory rate is the number of breaths per minute, with a normal range of 12-20 breaths per minute for adults
• Depth of respiration can be described as shallow, normal, or deep, indicating the volume of air moved with each breath
• Rhythm of respiration should be regular, with equal time spent on inspiration and expiration
• Chest expansion should be symmetrical, with both sides of the chest rising and falling equally during respiration
• Accessory muscle use (sternocleidomastoid, scalenes) may indicate respiratory distress or increased work of breathing
• Auscultation of lung sounds using a stethoscope can reveal normal (vesicular) or abnormal (crackles, wheezes, rhonchi) sounds
  • Crackles (rales) are discontinuous, popping sounds that may indicate fluid in the lungs (pulmonary edema, pneumonia)
  • Wheezes are continuous, high-pitched sounds that may indicate narrowing of the airways (asthma, COPD)
  • Rhonchi are continuous, low-pitched sounds that may indicate secretions in the larger airways
• Pulse oximetry is a non-invasive method to measure the oxygen saturation of hemoglobin (SpO2), with a normal range of 95-100%

Common Respiratory Disorders

• Asthma is a chronic inflammatory disorder characterized by reversible airway obstruction, causing wheezing, coughing, and dyspnea
• Chronic Obstructive Pulmonary Disease (COPD) is a progressive disorder that includes chronic bronchitis and emphysema, leading to airflow limitation and dyspnea
• Pneumonia is an infection of the lungs that causes inflammation and fluid accumulation in the alveoli, resulting in cough, fever, and difficulty breathing
• Acute Respiratory Distress Syndrome (ARDS) is a severe, life-threatening condition characterized by widespread inflammation and fluid accumulation in the lungs, leading to hypoxemia and respiratory failure
• Pulmonary embolism is a blockage of a pulmonary artery by a blood clot (thrombus), causing chest pain, dyspnea, and hypoxemia
• Pleural effusion is the accumulation of fluid in the pleural space, which can cause dyspnea and decreased lung function
• Sleep apnea is a disorder characterized by repeated pauses in breathing during sleep, leading to daytime fatigue and cardiovascular complications
  • Obstructive sleep apnea (OSA) is caused by a collapse of the upper airway during sleep
  • Central sleep apnea (CSA) is caused by a failure of the brain to send appropriate signals to the respiratory muscles

Oxygenation Therapies and Interventions

• Oxygen therapy involves the administration of supplemental oxygen to treat or prevent hypoxemia
  • Nasal cannula is a device that delivers low to moderate concentrations of oxygen (24-44%) through prongs inserted into the nostrils
  • Simple face mask delivers moderate to high concentrations of oxygen (40-60%) and is used for patients who require higher oxygen flow rates
  • Non-rebreather mask delivers high concentrations of oxygen (60-100%) by using a reservoir bag and one-way valves to prevent the inhalation of room air
• Positive pressure ventilation provides ventilatory support by delivering air or oxygen under positive pressure to the lungs
  • Continuous Positive Airway Pressure (CPAP) maintains a constant positive pressure throughout the respiratory cycle, helping to keep the airways open and improve oxygenation
  • Bilevel Positive Airway Pressure (BiPAP) delivers a higher pressure during inspiration and a lower pressure during expiration, providing both ventilatory support and improved oxygenation
• Mechanical ventilation is used for patients who are unable to maintain adequate ventilation or oxygenation on their own
  • Invasive mechanical ventilation involves the insertion of an endotracheal tube or tracheostomy tube to deliver breaths from a ventilator
  • Non-invasive ventilation (NIV) provides ventilatory support without the need for an artificial airway, using a tight-fitting mask (CPAP or BiPAP)
• Prone positioning involves placing the patient in a face-down position to improve oxygenation and reduce the risk of ventilator-associated lung injury in patients with ARDS
• Pulmonary rehabilitation is a comprehensive program that includes exercise training, education, and behavioral interventions to improve the physical and psychological well-being of patients with chronic respiratory disorders (COPD, asthma)

Nursing Care for Respiratory Patients

• Assess respiratory function regularly, including respiratory rate, depth, rhythm, and oxygen saturation
• Monitor for signs of respiratory distress, such as tachypnea, dyspnea, accessory muscle use, and cyanosis
• Administer oxygen therapy as prescribed, ensuring proper fit and flow rate of the delivery device
• Provide oral care and suctioning as needed to maintain a patent airway and prevent aspiration
• Assist with deep breathing and coughing exercises to promote lung expansion and secretion clearance
  • Incentive spirometry encourages deep breathing and sustained maximal inspiration, helping to prevent atelectasis and improve lung function
• Encourage early ambulation and mobility to prevent complications such as pneumonia and venous thromboembolism
• Monitor fluid balance and provide adequate hydration to thin secretions and facilitate expectoration
• Assess pain and provide appropriate pain management, as pain can lead to shallow breathing and decreased cough effectiveness

Respiratory Medications and Treatments

• Bronchodilators (beta-2 agonists, anticholinergics) relax smooth muscles in the airways, reducing bronchoconstriction and improving airflow
  • Short-acting bronchodilators (albuterol, ipratropium) are used for quick relief of symptoms
  • Long-acting bronchodilators (salmeterol, tiotropium) are used for long-term control of symptoms
• Corticosteroids (inhaled, oral) reduce inflammation in the airways, decreasing edema and mucus production
  • Inhaled corticosteroids (fluticasone, budesonide) are used for long-term control of asthma and COPD
  • Oral corticosteroids (prednisone, methylprednisolone) are used for acute exacerbations or severe symptoms
• Mucolytics (acetylcysteine, dornase alfa) thin and loosen mucus secretions, making them easier to expectorate
• Antibiotics are used to treat bacterial respiratory infections, such as pneumonia and acute exacerbations of COPD
• Oxygen therapy is used to treat or prevent hypoxemia, as discussed in the previous section
• Pulmonary hygiene techniques, such as chest physiotherapy and postural drainage, help to mobilize and clear secretions from the lungs
  • Chest physiotherapy includes techniques such as percussion, vibration, and shaking to loosen secretions
  • Postural drainage involves positioning the patient to use gravity to drain secretions from specific lung segments

Patient Education and Self-Management

• Teach patients and caregivers about the proper use and maintenance of respiratory medications and devices (inhalers, nebulizers, oxygen equipment)
  • Demonstrate proper inhaler technique (spacer use, coordination of actuation and inhalation)
  • Emphasize the importance of regular cleaning and replacement of equipment
• Educate patients about the signs and symptoms of respiratory distress and when to seek medical attention
• Encourage smoking cessation and provide resources for quitting, as smoking is a major risk factor for respiratory disorders
• Teach patients about the importance of regular exercise and physical activity in maintaining lung function and overall health
• Provide education on energy conservation techniques and pacing activities to manage dyspnea and fatigue
• Encourage patients to receive vaccinations (influenza, pneumococcal) to reduce the risk of respiratory infections
• Teach patients about the importance of a healthy diet and maintaining a healthy weight, as obesity can worsen respiratory symptoms
• Provide information on stress management and relaxation techniques, as stress and anxiety can exacerbate respiratory symptoms

Special Considerations and Complications

• Ventilator-associated pneumonia (VAP) is a common complication in patients receiving mechanical ventilation, requiring strict adherence to infection control practices (hand hygiene, oral care, head-of-bed elevation)
• Acute exacerbations of chronic respiratory disorders (asthma, COPD) can be triggered by infections, environmental factors, or non-adherence to medications, requiring prompt recognition and treatment
• Pulmonary hypertension is a complication of various respiratory disorders, characterized by increased blood pressure in the pulmonary arteries, leading to right ventricular strain and failure
• Respiratory failure is a life-threatening condition that occurs when the respiratory system cannot maintain adequate oxygenation or carbon dioxide removal, requiring immediate intervention and support
  • Hypoxemic respiratory failure is characterized by low blood oxygen levels (PaO2 < 60 mmHg) and may be caused by conditions such as ARDS, pneumonia, or pulmonary edema
  • Hypercapnic respiratory failure is characterized by high blood carbon dioxide levels (PaCO2 > 50 mmHg) and may be caused by conditions such as COPD, neuromuscular disorders, or oversedation
• End-of-life care for patients with advanced respiratory disorders requires a focus on symptom management, comfort measures, and emotional support for patients and families
  • Palliative care interventions may include oxygen therapy, opioids for dyspnea, and anti-anxiety medications
  • Advance care planning discussions should address goals of care, treatment preferences, and end-of-life wishes