Oxygenation and Respiration

Oxygenation Overview

• Oxygen, constituting about 21% of Earth's atmosphere, is vital for human life.
• Cells use oxygen to metabolize nutrients and produce energy.
• Without oxygen, cells quickly die.

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 can decrease gas exchange and ventilation efficiency.
• Functional respiratory changes in older adults include diminished cough and gag reflexes.
• Older adults may use accessory muscles more for breathing.
• Diminished efficiency of gas exchange in the lungs is possible with age.
• Increased mouth breathing and snoring may be observed.
• Lung volume changes can decrease overall efficiency and raise energy expenditure.
• Confusion or restlessness needs assessment to rule out oxygen deficit before assuming delirium or dementia.
• Encourage older adults needing home oxygen to socialize.
• Educate older adults and caregivers on portable oxygen.
• Check behind older adults' ears for skin breakdown from oxygen tubes/devices.
• Older adults may have facial seal issues with masks from weight loss/denture use.
• Advise annual flu and pneumonia immunization, with possible booster pneumonia dose after 5 years.

Anatomy and Physiology of Breathing

• Lung tissue elasticity allows expansion during inspiration and returning to a resting position with expiration.
• Ventilation is the air movement in/out of lungs, aiding respiration.
• Respiration is the oxygen and carbon dioxide exchange.
• External respiration happens between alveoli and capillaries.
• Internal respiration occurs at the cellular level involving hemoglobin and body cells.
• Increased blood carbon dioxide and hydrogen ions stimulate breathing.
• Ventilation is due to pressure changes in the thoracic cavity.
• During inspiration, the diaphragm goes down and intercostals move chest out.
• Expansion creates more chest space, decreasing lung pressure below atmospheric.
• Air is pulled in through the nose and lungs.
• Accessory muscles (pectoralis minor and sternocleidomastoid) help with greater chest expansion.
• During inspiration, chest cavity increases, but chest pressure decreases, allowing air to move into the lungs.
• Respiratory muscles relax and the thoracic cavity decreases during expiration.
• Intrathoracic pressure increases and air exits the respiratory tract.
• Contraction of abdominal muscles can forcibly exhale additional air.

Assessing Oxygenation

• Assess the quality of a client's oxygenation through physical assessment, arterial blood gases (ABGs), and pulse oximetry.
• These measures help identify hypoxemia and hypoxia.
• Hypoxemia is insufficient oxygen in arterial blood.
• Hypoxia is inadequate oxygen at the cellular level.

Physical Assessment

• Monitor respiratory rate.
• Observe breathing pattern and effort.
• Check chest symmetry.
• Auscultate lung sounds.
• Record heart rate and blood pressure.
• Determine consciousness level.
• Observe skin, mucous membranes, lips, and nail bed color.

Arterial Blood Gases (ABG)

• ABG assessment is a lab test to assess oxygenation, ventilation, and acid-base balance.
• ABGs measure PaO2, SaO2, PaCO2, blood pH, and bicarbonate (HCO3) levels.
• Arterial blood is preferred because arteries carry oxygen to all cells.
• ABGs are ordered to assess clients in respiratory distress or monitor medical treatment progress.
• A laboratory technician and nurse collaboratively collect arterial blood.
• The nurse notifies the laboratory of the need for the blood test.
• The nurse records assessments on the request form.
• The nurse prepares the client and assists the technician.
• Measures prevent complications after arterial puncture.
• A nurse trained in arterial punctures may obtain the specimen in emergencies.

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

• Assess all clients under 5 years of age, over 65 years, or anyone with a compromising chronic health condition for and offer Prevnar 13.

Arterial Blood Gas Procedure

• Perform Allen test before arterial puncture.
  • Flex client's elbow and elevate forearm.
  • Simultaneously compress radial and ulnar arteries.
  • Client opens/closes fist until palm blanches.
  • Release ulnar pressure, keeping radial pressure.
  • Observe skin for flush/blanch.
  • Release radial pressure.
• Allen test verifies adequate ulnar blood supply if radial artery damage occurs.
• Do not puncture radial artery if Allen test shows poor collateral flow.
• Alternative sites: brachial, femoral, or dorsalis pedis arteries.
• Keep client at rest for at least 30 minutes before unless an emergency, as activity can transiently lower oxygen.
• Record client's temperature, respiratory rate, and activity level, as increased metabolism/activity affects results.
• Record oxygen amount at test time and ventilator settings to help determine effectiveness.
• Hyperextend wrist over rolled towel for artery access.
• Comfort the client during puncture since it can be painful without local anesthetic.
• Expel air bubbles from specimen to ensure only contained gas is present.
• Rotate collected specimen to mix with anticoagulant and prevent clotting.
• Place specimen on ice immediately because cell deterioration affects oxygen content.
• Cool sample slows cell metabolism for accurate results.
• Apply direct manual pressure for 5-10 minutes since arterial blood flow is high pressure to control bleeding.
• Cover with pressure dressing of gauze squares and tape.
• Assess puncture site periodically for bleeding/hematoma.
• Report lab findings promptly to the provider to improve treatment.

Pulse Oximetry

• It is a noninvasive technique for monitoring blood oxygen saturation.
• The components include a sensor, red and infrared light emitter, and a microprocessor.
• The sensor is attached to finger, toe, earlobe, or nose bridge.
• The sensor detects the hemoglobin light absorption amount.
• Measurement of obtained oxygen saturation is abbreviated as SpO2.
• Infer PaO2 from pulse oximetry (SpO2) measurement.
• The normal SpO2 is 95% to 100%.
• A sustained less than 90% level is cause for concern.
• If SpO2 remains low, oxygen therapy may be needed.
• Factors affect accuracy of displayed information.

Promoting Oxygenation

• Factors impacting ventilation affect oxygenation.
• Positioning and breathing techniques are key interventions.
• Nasal strips reduce airway resistance for better ventilation.

Positioning

• Place hypoxic clients in high Fowler position.
• This position ease diaphragm movement and lung volume.
• Try tripod position in seated position/arms supported to help lift chest.
• Orthopneic position is leaning forward over bedside table or chair.
• Orthopneic allows maximal chest expansion and comfort.

Breathing Techniques

• Include deep breathing, incentive spirometer use, pursed-lip breathing, and diaphragmatic breathing.

Deep Breathing

• Deep breathing maximizes ventilation, filling alveoli.
• Encourage clients to take in as much air for full alveoli, hold breaths briefly, and exhale slowly.
• Use incentive spirometer.

Incentive Spirometry

• Incentive spirometry uses calibrated device to encourage goal-directed inspired air volume.

Factors Affecting Oxygenation

• Adequate respiration relies on a minimum of 21% environmental oxygen and normal cardiopulmonary function.
• Breathing can be voluntarily controlled.
• Chronic lung disease clients are stimulated by low oxygen.
• Smoking causes inhaled carbon monoxide competes for hemoglobin binding.
• Nicotine constricts blood vessels and increases heart rate.
• Smoking while pregnant increases low-birth-weight risks due to fetal oxygen.
• Pulmonary secretions and interstitial fluid interfere with gas exchange.
• Increased gas exchange requires maximum lung expansion.
• Activity/emotional stress increase oxygen needs.
• Abdominal/flank pain reduce deep breaths and forced coughs.

Oxygen Therapy

• When blood isn't saturated enough by positioning and techniques.
• It increases Oxygen to prevent/relieve hypoxemia.
• Requires source, flowmeter, and sometimes analyzer/humidifier.

Nursing Implications for Oxygenation Factors

• Cardiac/pulmonary disorders need more than 21% oxygen.
• Hyperventilating clients need slowed rates and pursed-lip breathing.
• COPD clients can have breathing depressed by high oxygen, avoid 2-3L unless mechanically ventilated.
• Smokers have damaged gas exchange.
• Teach to avoid smoking.
• Encourage fluids, coughing, turning, and ambulating to inflate alveoli.
• Assist clients to sit up and encourage weight loss to lower diaphragm compression.
• Provide rest and teach stress reduction for blood oxygen maintenance.
• Support incision with pillow after lung surgery and use pain relief.

Oxygen Sources

• Sources include wall outlets, portable tanks, liquid oxygen, oxygen concentrators.
• Wall outlets connect to a reservoir filled with oxygen.
• Portable tanks provide oxygen for transport.
• Liquid oxygen units convert cooled liquid oxygen to a gas.
• Oxygen concentrators collect oxygen from room air.

Portable Tanks

• Provide oxygen when wall outlets are not available or clients need transport.
• Hold pressurized volumes and need protective caps.
• "Cracking" the tank involves releasing debris from the outlet using wrench.

Liquid Oxygen Unit

• Coverts it to gas, used at home for better mobility.
• Small units contain 4 to 8 hours of oxygen.
• Some problems include expensive liquid oxygen, leaky unit, and frozen moisture.

Oxygen Concentrator

• Collects oxygen from room air
• Portable concentrators now exist and can be powered by car DC outlet or AC current.
• It Eliminates bulky tanks but needs secondary oxygen during power outages.

Oxygen Administration Equipment

• Flowmeter: regulates liters per minute of oxygen.
• Oxygen Analyzer: confirms the oxygen % delivered.
• Humidifier: adds moisture to oxygen to prevent mucosal drying, used above 4L/minute.

Oxygen Delivery Devices

• Nasal Cannula: Delivers low concentrations of oxygen - ideal for non-hypoxic/chronic lung clients.
• High-Flow Nasal Cannula: Delivers up to 100% oxygen
• Masks -Simple Mask: Used when nasal trauma exists. Delivers no less than 5L/minute. -Partial and Non-rebreather Mask: Delivers higher percentages of oxygen. -Venturi Mask: Delivers exact oxygen via color-coded adapters.

Tracheostomy Collar/T-Piece

• Artificial openings need humidification and oxygenation methods.

Oxygen Therapy Nursing Guidelines

• Post oxygen in use signs; oxygen supports combustion.
• No candles.
• Electrical devices must be grounded, inspect for frayed wires.
• Avoid petroleum/aerosol.
• Secure oxygen to stands.

Oxygen Toxicity

• Lung damage from concentrations of >50% over >48-72 hours, reduces surfactant that enhances elasticit.y
• Early symptoms are subtle; prevent with lowest FIO2 for shortest time.

Related Oxygenation Techniques

• Positive Airway Pressure: Relieves apnea/hypopnea with airway ventilation Continuous Positive Airway Pressure (CPAP): keeps alveoli inflated during expiration
• Bilevel Positive Airway Pressure (BiPAP): varies pressure with breath/promotes tolerance
• Water-Seal Chest Tube: Evacuates air or blood from the chest, restoring intrapleural pressure
• Hyperbaric Oxygen Therapy (HBOT): Delivers 100% oxygen, promotes new tissue.

Nursing Diagnoses

• Altered breathing pattern
• Impaired gas exchange
• Activity intolerance
• Chronic/acute anxiety
• Risk for ineffective airway clearance

Nursing Care Plan

• Assess respiratory rate, effort, chest symmetry, air entry
• Check pulse, BP, level of consciousness, and mental status
• Measure SpO2, assess skin color
• Perform auscultation of lung sounds
• Observe cough and sputum production
• Elevate the head and administer to promote optimal ventilation
• Teach pursed lip and diaphragmatic breathing
• Provide 2L of fluid intake.

Key Points

• Oxygen therapy is required to relieve hypoxemia using nasal cannula, mask or mechanical intubation
• Monitor ABGs or pulse oximetry to determine effectiveness.
• Observe for signs of respiratory distress, reduced energy, rapid, shallow breathing is not effective oxygenation.
• Assess breath sounds due to wheezing, stridor is not indicative of adequate oxygen.