Oxygenation and Respiration

• Oxygenation is essential for life, as each cell uses oxygen to metabolize nutrients and produce energy
• Without oxygen, cell death occurs rapidly

Learning Objectives

• Explain the difference between ventilation and respiration
• Differentiate between external and internal respiration
• Name methods for assessing the oxygenation status of clients at the bedside
• List signs of inadequate oxygenation
• Name nursing interventions that can be used to improve ventilation and oxygenation
• Name sources for supplemental oxygen
• Identify items that may be needed when providing oxygen therapy
• List common oxygen delivery devices
• Discuss hazards related to the administration of oxygen
• Describe additional therapeutic techniques that relate to oxygenation
• Discuss facts concerning oxygenation that affect the care of older adults

Gerontologic Considerations

• Age-related changes affect respiratory function in older adults
• Functional changes include diminished cough and gag reflexes
• Increased use of accessory muscles for breathing
• Diminished efficiency of gas exchange occurs in the lungs
• Increased mouth breathing and snoring may occur in older adults
• Lung volumes change, decreasing efficiency and increasing energy expenditure
• Restlessness or confusion needs careful assessment to differentiate signs of inadequate oxygenation from delirium or dementia
• Encourage older adults on home oxygen to socialize to prevent isolation
• Teach older adults and caregivers how to use portable oxygen equipment
• Assess skin behind the ears for breakdown from oxygen tubing
• Older adults with weight loss or without dentures may not get an adequate facial seal with a mask
• Advise older adults to receive annual influenza and pneumonia immunizations

Anatomy and Physiology of Breathing

• Lung elasticity allows them to stretch during inspiration and return to a resting position after expiration
• Ventilation (air movement in/out of lungs) facilitates respiration (O2 and CO2 exchange)
• External respiration occurs in the alveoli between alveolar and capillary membranes
• Internal respiration happens at the cellular level involving hemoglobin and body cells
• Increased carbon dioxide and hydrogen ions stimulate breathing
• Ventilation results from pressure changes in the thoracic cavity due to respiratory muscle contraction and relaxation
• During inspiration, the diaphragm contracts and intercostal muscles expand the chest cavity, decreasing pressure and allowing air to flow in
• During expiration, respiratory muscles relax, the thoracic cavity decreases, and air moves out

Assessing Oxygenation

• Nurses assess oxygenation through physical assessment, arterial blood gases (ABGs), and pulse oximetry
• These measures help identify hypoxemia (insufficient oxygen in arterial blood) and hypoxia (inadequate oxygen at the cellular level)

Physical Assessment

• Assessing respiratory rate, breathing pattern and effort, chest symmetry, and lung sounds is important
• Also assess the heart rate and blood pressure, level of consciousness, and skin color

Arterial Blood Gases

• ABG assessment evaluates oxygenation, ventilation, and acid-base balance
• Measures PaO2 (partial pressure of oxygen), SaO2 (oxygen saturation), PaCO2 (partial pressure of carbon dioxide), pH, and bicarbonate (HCO3) levels

Common Signs of Inadequate Oxygenation

• Decreased energy
• Restlessness
• Rapid, shallow breathing
• Rapid heart rate
• Sitting up to breathe
• Nasal flaring
• Use of accessory muscles
• Hypertension
• Sleepiness, confusion, stupor, coma

Pharmacologic Considerations

• Clients under 5 years of age, over 65 years, or anyone with a compromising chronic health condition should be assessed for and offered Prevnar 13, a pneumococcal vaccine

Nursing Guidelines for Assisting with an Arterial Blood Gas (ABG)

• Perform Allen test to ensure ulnar artery supplies blood to hand
• Keep client at rest for at least 30 minutes before unless it is an emergency
• Record temperature, respiratory rate, level of activity
• Note oxygen amount
• Comfort client; puncture may be painful so local anesthetic should be used
• After obtaining, remove air bubbles
• Rotate specimen mix with anticoagulant
• Put on ice to ensure accurate results
• Apply direct manual pressure to arterial puncture site for 5 to 10 minutes
• Cover with pressure dressing; monitor for bleeding/hematoma
• Report results quickly for adjustments in treatment

Pulse Oximetry

• Pulse oximetry monitors blood oxygen saturation noninvasively
• It uses a sensor with a photodetector, red and infrared light emitter, and microprocessor
• The sensor is attached to finger, toe, earlobe, or nose bridge
• It detects light absorbed by hemoglobin
• Normal SpO2 is 95%-100%; less than 90% is a concern

Factors That Interfere with Accurate Pulse Oximetry

• Movement of the sensor
• Poor circulation at the sensor site
• Barrier to light
• Extraneous light
• Hemoglobin saturation with other substances

Promoting Oxygenation

• Positioning and breathing techniques are used to promote oxygenation
• Adhesive nasal strips reduce nasal airway resistance and improve ventilation

Positioning

• High Fowler's position eases breathing by allowing abdominal organs to descend
• Tripod position supports the arms and lifts the chest, increasing breathing capacity
• Orthopneic position involves leaning forward on a table or chair for chest expansion

Breathing Techniques

• Deep breathing, pursed lip breathing, and diaphragmatic breathing help clients breathe more efficiently

Deep Breathing

• Deep breathing maximizes ventilation by filling alveoli to a greater capacity
• Encourages slow, deep breaths, holding briefly, and exhaling slowly

Incentive Spirometry

• Uses a calibrated device for deep breathing, to encourage clients to breath to reach a goal-directed volume of inspires air

Pursed-Lip Breathing

• Pursed-lip breathing prolongs expiration, improving gas exchange and eliminating carbon dioxide
• Inhale slowly through the nose and exhale slowly through pursed lips

Diaphragmatic Breathing

• Diaphragmatic breathing uses the diaphragm rather than upper chest muscles to increase air exchange
• Reduces respiratory effort and relieves rapid, ineffective breathing

Nasal Strips

• Nasal Strips reduce airflow resistance

Oxygen Therapy

• Oxygen therapy administers more oxygen than is present in the atmosphere to prevent or relieve hypoxemia
• Requires an oxygen source, flowmeter, oxygen analyzer/humidifier, and delivery device

Oxygen Sources

• Wall outlet
• Portable tank
• Liquid oxygen unit
• Oxygen concentrator

Equipment Used in Oxygen Administration

• Flowmeter
• Oxygen analyzer
• Humidifier

Flowmeter

• Measures oxygen in liters per minute (L/minute) to regulate the amount delivered

Oxygen Analyzer

• Measures percentage of delivered oxygen to ensure correct amount is delivered

Humidifier

• Adds moisture with administration as oxygen is drying to mucous membranes
• Used with more than 4 L/minute of oxygen

Common Delivery Devices

• Nasal cannula
• Masks (simple, partial rebreather, nonrebreather, venturi)
• Face tent
• Tracheostomy collar
• T-piece

Nasal Cannula

• A nasal cannula is a hollow tube with prongs in the nostrils
• It delivers low concentrations of oxygen
• Appropriate for non-hypoxic clients or those with chronic lung disease
• Clients with chronic lung disease shouldn't receive more than 2 to 3L as it may slow or stop their respiratory rate

Masks

• Simple mask: Fits over nose and mouth with side ports for air to enter and exit.
• Partial rebreather mask: Has a reservoir bag; recycles oxygen and vents all the carbon dioxide during expiration and all.
• Nonrebreather mask: Prevents rebreathing of exhaled air and delivers high oxygen concentrations
• Venturi mask: mixes oxygen and atmospheric air; delivers exact amount prescribed

Tracheostomy Collar

• Delivers oxygen near a tracheostomy, providing oxygenation and humidification

T-Piece

• Fits securely onto a tracheostomy or endotracheal tube
• Similar to a tracheostomy collar
• Guaze dressing and the T-piece may collect moisture and put weight on the tube

Oxygen Hazards

• Fire potential: Oxygen supports combustion
• Oxygen toxicity: Lung damage from high concentrations for extended periods

Nursing Implications for Oxygen Therapy

• Assess oxygenation status regularly
• Recognize potential diagnoses for hypoxemia
• Altered breathing pattern
• Impaired gas exchange
• Activity intolerance
• Chronic/acute anxiety
• Risk for ineffective airway clearance

Additional Oxygenation Techniques

• Positive airway pressure machines
• Water-seal chest tube drainage systems
• Hyperbaric Oxygen Therapy (HBOT) treatments

Positive Airway Pressure (PAP) Machines

• Positive airway pressure machines relieve impaired oxygen levels due to apnea or hypopnea during sleep
• Muscles relax, obstructing the airway
• Continuous Positive Airway Pressure (CPAP) masks keep alveoli partially inflated
• Bilevel Positive Airway Pressure (BiPAP) masks provide two pressure levels for better tolerance

Water-Seal Chest Tube Drainage

• It is a technique that helps evacuate air or blood from the pleural cavity and helps restore negative intrapleural pressure and reinflate the lung
• A three-chamber system
• One chamber collects blood/acts as an exit route for pleural air
• A second compartment holds water acting as water seal
• A thrid chamber facilitates the use of suction
• The chest tube must never be separated or unclamped unless it is clamped
• The tube is clamped for only a brief time

Hyperbaric Oxygen Therapy (HBOT)

• HBOT delivers 100% oxygen at three times normal atmospheric pressure in an airtight chamber
• It regenerates new tissue faster, promoting wound healing
• Treats carbon monoxide poisoning, gangrene, decompression sickness and anaerobic infections

Nursing Care for Impaired Gas Exchange

• Assessment of respiratory rate and effort
• Pulse, BP, assess level of consciousness
• Assess cough
• Observe chest contour and use of accessory muscles
• Inspect the skin, oral mucous membranes and nail beds
• Auscultate lungs
• Diagnostic: Impaired gas exchange related to the retention of carbon dioxide secondary to chronic pulmonary damage from long-term cigarette smoking
• Intervention: Provide rest, position client comfortably, teach breathing exercises, adequate oral fluids, and monitor ABGs/oxygen saturation
• Monitor for signs and symptoms of respiratory acidosis