Oxygenation and Respiration

• Oxygenation is essential for sustaining life because each cell uses oxygen to metabolize nutrients and produce energy.

Learning Objectives Review

• Ventilation is the movement of air in and out of the lungs, while respiration is the exchange of oxygen and carbon dioxide.
• External respiration occurs between the alveoli and pulmonary capillaries, while internal respiration occurs at the cellular level.
• bedside assessment methods include monitoring respiratory rate, breathing pattern, oxygen saturation, and signs of respiratory distress.
• Signs of inadequate oxygenation include decreased energy, restlessness, rapid breathing, rapid heart rate, nasal flaring, and confusion.
• Nursing interventions to improve ventilation and oxygenation include positioning, deep breathing exercises, and administering supplemental oxygen.
• Sources for supplemental oxygen include wall outlets, portable tanks, liquid oxygen units, and oxygen concentrators.
• Items needed when providing oxygen therapy include an oxygen source, flowmeter, oxygen analyzer, humidifier, and delivery device.
• Common oxygen delivery devices include nasal cannulas, masks, face tents, tracheostomy collars, and T-pieces.
• Hazards related to oxygen administration include fire risk and oxygen toxicity
• Other therapeutic techniques that relate to oxygenation include positive airway pressure machines, water-seal chest tube drainage, and hyperbaric oxygen therapy.
• Age-related changes affecting oxygenation in older adults include reduced gas exchange, diminished reflexes, and increased mouth breathing.

Gerontologic Considerations

• Age-related changes like reduced gas exchange and diminished cough reflexes can affect respiratory function.
• Restlessness or confusion in older adults needs careful assessment to differentiate inadequate oxygenation from delirium.
• Older adults using home oxygen should be encouraged to socialize to avoid isolation and depression and should be educated on portable oxygen equipment.
• Skin behind the ears should be assessed in older adults using oxygen tubing.
• Older adults with weight loss may need special fitting for oxygen masks.
• Older adults should receive annual influenza and pneumonia immunizations.

Anatomy and Physiology of Breathing

• Lung elasticity allows for stretching during inspiration and recoil during expiration.
• Ventilation facilitates respiration, where oxygen and carbon dioxide are exchanged.
• External respiration occurs in the alveoli, while internal respiration occurs at the cellular level.
• Increased carbon dioxide and hydrogen ions stimulate breathing.
• Ventilation results from pressure changes caused by respiratory muscle contraction and relaxation.
• During inspiration, the diaphragm contracts, and intercostal muscles elevate the ribs, expanding the thoracic cavity and decreasing pressure.
• During expiration, respiratory muscles relax pushing air out of the lungs
• Accessory muscles like the pectoralis minor and sternocleidomastoid assist with chest expansion in acute oxygen needs.

Assessing Oxygenation

• Quality is assessed through physical assessment, arterial blood gases (ABGs), and pulse oximetry.
• Hypoxemia is insufficient oxygen in arterial blood, while hypoxia is inadequate oxygen at the cellular level.
• Physical assessment involves monitoring respiratory rate, breathing pattern, chest symmetry, and lung sounds.
• Additional assessments include heart rate, blood pressure, level of consciousness, and skin color.

Arterial Blood Gases (ABG)

• An ABG assessment evaluates oxygenation, ventilation, and acid-base balance.
• It measures PaO2, SaO2, PaCO2, pH, and bicarbonate levels.
• Arterial blood sampling is preferred due to its higher oxygen content.
• Initial and subsequent ABGs assess acute respiratory distress or monitor treatment progress.
• Collaboration with a lab technician is typical for blood collection.
• The nurse records assessments, assists with collection, and prevents complications after puncture.

Nursing Guidelines: Assisting with Arterial Blood Gas (ABG)

• Perform the Allen test to ensure adequate ulnar arterial blood supply.
• Keep the client at rest for at least 30 minutes before obtaining the specimen.
• Record the client's temperature, respiratory rate, level of activity, and oxygen amount.
• Comfort the client, as the procedure is painful.
• Expel air bubbles after obtaining the specimen.
• Rotate the collected specimen for proper mixing of the anticoagulant.
• Place the specimen on ice for accurate test results.
• Apply direct manual pressure to the arterial puncture site for 5 to 10 minutes.
• Cover the puncture site with a pressure dressing.
• Assess the puncture site periodically for bleeding or hematoma formation.
• Report the laboratory findings to the prescribing physician.

Pulse Oximetry

• It is a noninvasive technique for monitoring blood oxygen saturation.
• It uses a photodetector sensor, a red and infrared light emitter, and a microprocessor.
• The sensor is attached to a finger, toe, earlobe, or the bridge of the nose.
• The measurement of oxygen saturation by pulse oximetry is abbreviated as SpO2.
• A normal SpO2 is 95% to 100%.
• A sustained level below 90% is cause for concern.
• Troubleshooting, physical assessments, and ABG help confirm significance.

Factors that Interfere with Accurate Pulse Oximetry

• Tremor, restlessness, or loss of adhesion can cause movement interference. Relocate sensor to another site.
• Peripheral vascular disease or edema lead to poor circulation.
• Nail polish, and acrylic nails create a barrier to light. Remove polish or acrylic nails.
• Direct sunlight and treatment lights add extraneous light. Cover sensor with a towel.
• Carbon monoxide poisoning saturates hemoglobin with other substances. Discontinue use temporarily.

Promoting Oxygenation

• Positioning and breathing techniques are common interventions used.
• High Fowler position eases breathing by allowing abdominal organs to descend improving lung filling.
• Alternative positions are a tripod position and orthopneic position.
• Breathing techniques like deep breathing and pursed-lip breathing help clients breathe more efficiently.
• Deep breathing maximizes ventilation
• Incentive spirometry encourages clients to reach a goal-directed inspiratory volume.

Nursing Implications for Oxygenation

• Clients with cardiopulmonary disorders require > 21% oxygen.
• Assist clients who are hyperventilating to slow the rate of breathing.
• High oxygen percentages can depress breathing in clients with chronic lung disease.
• Smoking compromises gas exchange.
• Pulmonary secretions and fluid interfere with gas exchange.
• Maximize lung expansion, which is compromised by compression.
• Activity and stress increase the metabolic need for oxygen.
• Pain decreases the incentive to breathe deeply and cough forcefully.

Client and Family Teaching: Using an Incentive Spirometer

• Sit upright unless contraindicated.
• Identify the mark indicating the goal for inhalation.
• Exhale normally.
• Insert the mouthpiece, sealing it between the lips.
• Inhale slowly and deeply until the predetermined volume has been reached.
• Hold the breath for 3 to 6 seconds.
• Remove the mouthpiece and exhale normally.
• Relax and breathe normally before the next breath with the spirometer.
• Repeat the exercise 10 to 20 times/hour.

Pursed-Lip Breathing

• It is a form of controlled ventilation where expiration is prolonged.
• It Improves gas exchange and helps eliminate more carbon dioxide.
• It is helpful for clients who have COPD, which is characterized by chronic hypoxemia and hypercarbia.
• Inhale slowly through the nose while counting to three.
• Purse the lips as though to whistle.
• Contract the abdominal muscles.
• Exhale through pursed lips for a count of six or more.
• Expiration should be two to three times longer than inspiration.

Diaphragmatic Breathing

• It promotes the use of the diaphragm rather than upper chest muscles. It increases the volume of air exchanged.
• With practice, it reduces respiratory effort and relieves rapid, ineffective breathing.

Client and Family Teaching: Diaphragmatic Breathing

• Lie down with knees slightly bent.
• Place one hand on the abdomen and the other on the chest.
• Inhale slowly and deeply through the nose while letting the abdomen rise more than the chest.
• Purse the lips.
• Contract the abdominal muscles and begin to exhale.
• Press inward and upward with the hand on the abdomen while continuing to exhale.
• Repeat the exercise for 1 full minute; rest for at least 2 minutes.
• Practice the breathing exercises at least twice a day for a period of 5 to 10 minutes.
• Progress to diaphragmatic breathing while upright and active.

Nasal Strips

• Adhesive nasal strips reduce airflow resistance.
• They widen the breathing passageways of the nose.
• They promote easier breathing. Common users are people with ineffective breathing and athletes.

Oxygen Therapy

• It is an intervention for administering more than is present in the atmosphere to prevent or relieve hypoxemia.
• It requires an oxygen source, a flowmeter, an analyzer or humidifier, and a delivery device.
• Oxygen is supplied from a wall outlet, portable tank, liquid oxygen unit, or oxygen concentrator.

Oxygen Sources

• Wall Outlet
  • It is connected to a large central reservoir.
• Portable Tanks
  • They hold various volumes under extreme pressure thus require a protective cap.
  • The tank is "cracked" before use to clear the outlet.
• Liquid Oxygen Unit
  • It converts cooled liquid oxygen into gas.
  • They have greater ambulatory mobility.
• Oxygen Concentrator
  • It collects and concentrates oxygen from room air.
  • It takes in room air, removes nitrogen, and provides up to 95% pure oxygen. An oxygen concentrator eliminates the need for bulky tanks.

Equipment Used in Oxygen Administration

• Flowmeter
  • The flow of oxygen is measured in liters per minute (L/minute).
  • It is a gauge used to regulate the amount of oxygen delivered to the client.
• Oxygen Analyzer
  • It measures the percentage of delivered oxygen.
• Humidifier
  • It produces small water droplets.
  • It is used because oxygen dries the mucous membranes.
  • Oxygen is humidified only when more than 4 L/minute is administered.

Common Delivery Devices

• Nasal Cannula
  • It delivers a low concentration of oxygen.
  • Contraindicated for clients with chronic lung disease.
• Masks: Simple, Partial Rebreather, Nonrebreather, Venturi
• Face Tent
  • It provides a comfortable fit.
• Tracheostomy Collar
  • It delivers oxygen near an artificial opening in the neck.
• T-piece
  • The piece that fits securely onto a tracheostomy or endotracheal tube.

Oxygen Hazards

• Fire Potential
  • Oxygen supports combustion
  • All sources of open flames or ungrounded electricity must be controlled.
• Oxygen Toxicity
  • Lung damage develops when oxygen concentrations of more than 50% is administered for longer than 48 to 72 hours.
  • It reduces surfactant.

Related Oxygen Techniques

• Positive Airway Pressure Machines
  • They help relieve impaired oxygen levels caused by apnea or hypopnea during sleep.
  • They treat temporary relaxation of supporting muscles of soft palate and tongue, causing an obstruction.
  • CPAP maintaines the alveoli partially inflated
• Water-Seal Chest Tube Drainage
• A technique for evacuating air or blood from the pleural cavity
• Hyperbaric Oxygen Therapy
  • It helps regenerate new tissue faster.

Nursing Guidelines: Administering Oxygen Safely

• Post "Oxygen in Use" signs wherever oxygen is stored or in use.
• Prohibit the burning of candles during religious rites.
• Check that electrical devices have a three-pronged plug.
• Inspect electrical equipment for frayed wires or loose connections.
• Avoid using petroleum products, aerosol products and products containing acetone.
• Secure portable oxygen cylinders to rigid stands.