Respiratory Flashcards
3 Step Process of Oxygenation
- Ventilation (moving gases in and out of lungs)
- Perfusion (oxygenated blood to tissue and deoxygenated blood to lungs)
- Diffusion (movement of molecules from high to low concentration)
Factors that compromise oxygenation
- Physiological (cardiac disorders, anemia, pregnancy, fever, infection, CNS, chest wall conditions)
- Developmental (aging, decreased ability for the lungs to expand)
- Lifestyle (smoking, obesity, malnourishment)
- Environmental (smog, asbestos, high altitudes)
Partial pressure of oxygen or carbon dioxide
Amount of oxygen or carbon dioxide dissolved in plasma
Normal arterial oxygen tension (PaO2)
80-100 mmHg
Normal arterial carbon dioxide tension (PaCO2)
35-45 mmHg
Hyperventilation
Ventilation greater than required (exhaling more than you inhale)
- decreased level of CO2 in blood
- at the alveoli level
- clinical presentation: increased depth and rate
Causes of hyperventilation
- anxiety
- infections
- fever
- shock
- acid-base imbalance
- meds (i.e. ASA, amphetamines)
Hypoventilation
Ventilation less than required
- elevation of carbon dioxide
- alveolar ventilation is inadequate in meeting body’s oxygen demand
Atelectasis
collapse of the alveoli that prevents normal respiratory exchange of O2 and CO2 (lead to hypoventilation)
Causes of hypoventilation
- atelectasis
- inappropriate administration of excess O2 in patients with COPD
COPD
adapted to high CO2 level, their stimulus to breathe is low O2 concentrations
if O2 concentration increase, respiratory rate decreases
pulse oximetry levels: high 80s to low 90s
Hypoxia
inadequate tissue oxygenation at the cellular level
- life threatening condition
- can result in dysrhythmia and possibly death
Causes of hypoxia
- decreased hemoglobin level and lowered O2 carrying capacity
- decreased concentration of O2 (high altitude)
- inability of tissue to extract O2 from blood
- decreased diffusion of O2 from alveoli to blood (pneumonia)
- poor tissue perfusion (shock)
- impaired ventilation
signs and symptoms of hypoxia
- restlessness
- apprehension/agitation
- declining LOC
- dizziness
- fatigue
- increased pulse, resps and bp (unless caused by shock) (decreased vitals when things get worse)
- cyanosis (around lip)
Pulmonary Function Test (PFT)
- measures lung volume and capacity
- done by RT
- take deep breath and forcefully exhale
Arterial Blood Gases (ABG)
- measures the adequacy of tissue oxygenation
- radial artery most commonly used
- pH: 7.35 - 7.45
Pulse Oximetry (SpO2)
indirect measure of oxygen saturation
99% = 99% of hemoglobin have O2 attached
Normal = 95 - 100%
70% or lower is considered life threatening
Imaging
xray and CT scans provide visualization of lung fields
Common Respiratory Tests
- Pulmonary Function Test (PFT)
- Arterial Blood Gases (ABG)
- Pulse Oximetry (SPO2)
- Imaging
Factors that affect pulse oximetry
- poor peripheral circulation
- nail polish
- artificial nails
- tremors
Potential Nursing Diagnoses of Respiration
- ineffective airway clearance
- ineffective breathing pattern
- impaired gas exchange
- impaired spontaneous ventilation
- ineffective tissue perfusion
Interventions for Airway Maintenance
- Mobilization of pulmonary secretions (humidification, nebulization, chest physiotherapy, postural drainage)
- Suctioning
- Artificial airways
Humidification
- process of adding water to gas
- keeps airways moist and helps to loosen secretions
- needed for clients receiving O2 > 4 lpm
oral or nasal passage humidifies air naturally
Nebulization
- process of adding moisture or medications to inspired air
- improves clearance of pulmonary secretions
- often used for administration of bronchodilators and mucolytic agents (thins secretion)
Chest Physiotherapy (CPT)
- for loosening secretions
- for pts who have collapsed alveoli
- vibrations (during exhale)
Contraindication to CPT
- bleeding disorders
- fractured ribs
- steroid medications
Postural drainage
- using different positioning technique to draw out secretions
- typically an order
- be mindful of patient’s tolerance level and contraindications (head injury, cognitive status, aneurysm)
Types of suctioning
- oropharyngeal and nasopharyngeal (pt has effective cough but unable to clear secretions by expectorating or swallowing)
- orotracheal and nasotracheal (pt unable to manage secretion and does not have an artificial airway - can’t cough, spit or swallow)
- tracheal suction (suction via artificial airway)
Principles of suctioning
trachea is considered sterile and mouth is considered clean
suctioning of oral secretions after suctioning of the oropharynx and trachea
Suction devices
- Yankauer (for oropharyngeal)
- Flexible suction catheter/soft suction catheter
- the smaller the size (French), the smaller the catheter, depending on thickness of the secretion
6-10 French for infant and children
12-16 French for adult (14 avg)
Suctioning Considerations
- nasal route (nasopharyngeal and nasotracheal) preferred to prevent gag reflex
- Contraindications to naso: nose bleed, bronchospasm, epiglottitis, myocardial infarction)
- No absolute contraindication to tracheal suctioning
Suctioning Technique
- assess pt (include SPO2)
- semi-fowler’s
- no suction during insertion of catheter
- rotate and apply intermittent suction during withdrawal
- suction pressure between 100-150 mmHg
- should not exceed 10 seconds per pass
- encourage pt to cough before suctioning
- administer O2 between passes
Specific Suctioning Technique
nasopharyngeal and nasotracheal
- water soluble lubricant
- insert during inhalation
- nasopharyngeal: approx 15-20 cms
- nasotracheal: approx 20 cms, turn head L for R bronchus, R for L bronchus
tracheal
- choose suction catheter no bigger than 50% of airway diameter
- hyperoxygenate before starting
- if able, cough to get mucus into trachea
Artificial Airways
- Oral
- Nasal
- Tracheal (endotracheal and tracheal tubes)
Indications for artificial airways
- decreased LOC
- airway obstruction
- help with removal of secretions
Oral airways
- measure from corner of mouth to angle of jaw
- not to use if gag reflex and after oral surgery
Nasal airways
- measure from nose to ear lobe
- patient is conscious but may have decreased LOC
- patient getting oropharyngeal suctioning
Endotracheal tube (ETT)
- inserted by physician or RT
- meant for short term ventilation (no more than 14 days)
- balloon at the end inflated to keep in place
Tracheostomy Tube
- more permanent
- some have balloon cuffs to keep in place, may cause trauma
- some patients can talk
Bag Valve Mask (ambu-bag)
- used in emergency
- turned on high, 15 L/min
- C and E position
- 1 half squeeze per 6-8 seconds, enough to see chest rise and fall
Promotion of Lung Expansion
Non-invasive methods
- ambulation
- positioning (sit up, fowler’s or higher)
- cough techniques and deep breathing exercises
- incentive spirometer (IS)
Invasive method
- chest tubes
Incentive Spirometer
encourage voluntary deep breathing by providing visual feedback about inspiratory volume
Chest tubes
- inserted to remove air and fluid from pleural space
- catheter inserted through the thorax
- commonly used after chest surgery and chest trauma
Maintenance and promotion of oxygenation
To prevent or relieve hypoxia
- 02 is a drug to be used only when indicated, usually an order
- concentration (FiO2) = mixture of room air and O2 delivered to patient (i.e. 28%)
low flow device: nasal cannulas, simple face masks, reservoir masks, face tent
- oxygen concentration varies depending on breathing pattern
high flow device: venturi mask
- deliver O2 rate above normal inspiratory flow rate
Oxygen supplies
- Wall units
- Portable O2 tank (tip: check level before ambulating)
- Equipment
Nasal Cannula
- nasal prongs
- typically 4 L/min (up to 6 L/min)
- risk of skin breakdown and drying to the nose
Face Mask
- should be fitted loosely
- used for delivering 40-60% concentration
- contraindication: COPD
WITH RESERVOIR BAG
- delivers 60-80% O2 concentration
- 10 L/min to keep bag inflated
Venturi Mask
- high flow device
- must set O2 level
- contains venturi barrel
- 24-60% concentration, 4-12 L/min
- helpful for COPD with fixed amount of O2 concentration
Safety Precautions
- O2 is highly combustible
- no smoking
- ensure equipment works properly
- check level of portable tanks prior to ambulating
Adverse Effect of O2 administration
- nosocomial infections
- skin breakdown
- hypoventilation in patient with COPD
- oxygen toxicity
Oxygen toxicity
receiving O2 at concentration greater than 50% for more than 24 hrs
- damage to alveolar-capillary membrane
- use lowest concentration possible
manifestations: dyspnea, nasal congestion, cough, sore throat, chest pain with deep breathing
