Respiratory Flashcards
What is the primary function of the respiratory system?
Gas exchange between atmospheric air in
alveoli and blood in pulmonary circulation
Explain the difference between ventilation, diffusion, perfusion, and oxygenation
Ventilation: movement of air in and out of the lungs
Diffusion: Gas exchange. Oxygen moves from the lungs into the blood, and carbon dioxide moves from the blood into the lungs to be exhaled
Perfusion: This is blood flow. It’s how oxygen-rich blood is delivered to organs and tissues through the bloodstream.
Oxygenation: How much oxygen is available in the blood for the body to use
What is anatomic dead space? Where does this occur in the respiratory system?
Where air moves in and out but does not participate in gas exchange
Mouth, nose etc
What is the difference between hypoxemia and hypoxia?
How do we test for hypoxemia? Hypoxia?
Hypoxemia: low oxygen levels in blood. ABG
Hypoxia: low oxygen levels in tissues. Pulse ox
What happens to ABG levels in hypoventilation?
How does this affect pH and PaCO₂?
Hypoventilation:
Since breathing is slow, paCO2 builds up in the blood instead of being exhaled.
CO2 is acidic, so it decreases PH.
How does hyperventilation affect ABG results and oxygenation?
Since breathing is fast, paCO2 is being breathed out too quickly
PH goes up because losing CO2 makes the blood less acidic.
What is restrictive lung disease?
Compliance?
Diseases?
Lungs cannot fully expand, so they hold less air than normal.
↓ compliance = harder for the lungs to inflate leads to lung stiffness, limits expansion and difficulty inhaling
ARDS, pneumonia
Decreased compliance => Increased restriction
What is obstructive lung disease?
Compliance?
Disease?
Air gets trapped in the lungs and cant fully exhale because the airways are narrow or blocked
COPD, emphysema
Increased compliance => Decreased restriction
What are the differences between respiratory and metabolic causes of acidosis and alkalosis?
Respiratory causes involve changes in PaCO₂ (carbon dioxide levels).
Metabolic causes involve changes in HCO₃⁻ (bicarbonate levels)
What does V mean?
What does Q mean?
Normal?
Ideal?
What does a low V/Q mean?
What does a high V/Q mean?
What conditions would cause a low V/Q?
A high V/Q?
Both cause?
V: Amount of air reaching the alveoli
Q: Volume of blood passing through lungs
Normal: 0.8
Ideal: 1.0
Low V/Q: Less air but too much blood to pick up the air.
COPD, Pulmonary edema
High V/Q: Air coming in, but not enough blood to pick up the air.
Pulmonary embolism, hypovolemic shock
Both mismatches cause hypoxemia
What is the difference between relative and absolute shunts?
What are the criteria for hypoxemic and hypercapnic respiratory failure?
Absoulte Shunt: NO gas exchange
Relative Shunt: Some exchange, but not enough
Hypoxemic Respiratory Failure
Low Oxygen, Normal/Low CO₂
PaO₂ < 60 mmHg (low oxygen)
PaCO₂ normal or low
Hypercapnic Respiratory Failure
High CO₂, Low Oxygen
PaCO₂ > 45 mmHg (too much CO₂)
pH < 7.35 (acidosis)
When should oxygen therapy be initiated, and what are the goals of oxygenation?
Oxygen therapy should be started when a patient shows signs of hypoxemia
Correct hypoxemia / hypoxia
Always administer O2 at the lowest possible FiO2 (O2 concentration)
What is the key clinical manifestation of ARDS?
Refractory hypoxemia (low o2 levels that dont improve with extra oxygen)
Explain the use of prone positioning and PEEP in the management of ARDS.
Patient is placed on their stomach
Improves air flow and oxygen
Improves V/Q
Do it 12-16 hours a day
PEEP: Positive End Expiratory Pressure
Extra air pressure given by a ventilator to keep the alveoli open when a patient breathes out.
How do we manage ARDS patients? Focus on the bolded categories (not all the things underneath):
-Protective lung ventilation?
-Nutritional needs?
-Pharmacotherapy?
Low tidal volume (4-8 mL) are used to protect fragile lungs
Enteral feeding/TPN
Albumin
Watch I/Os
Cortecosteroids
Inhaled nitric oxide
What are the indications for using CPAP or BiPAP? Contraindications?
Patient must be?
What does CPAP do?
What does BIPAP do?
Contraindicated for?
Patient must be awake and alert with respiratory drive!!!!
CPAP: Provides constant positive pressure. Keeps the airways open throughout the respiratory cycle.
BiPAP: Provides higher pressure on inhalation and lower pressure on exhalation
*Most often used for pts with COPD and those in more severe resp distress
Contraindicated for:
Decreased level of consciousness
High O2 requirements
Decreased respiratory drive
Facial trauma
Hemodynamic instability
Excess secretions
What are priority assessments when implementing oxygen therapy?
Monitor the patient’s response to O2 therapy
Assess:
-Changes in mental status
-Vital signs – Especially respiratory rate and O2
-ABGs
Under what circumstances would you consider intubation over non-invasive options???
Patient is not awake, alert, or has an intact airway with respiratory drive
What are the advantages of a tracheostomy?
Easier to keep clean
better oral & bronchial hygiene
patient comfort increased
less risk of long-term damage to vocal cords
What should always be at bedside for a patient with a new tracheostomy?
Always have a replacement tube at
bedside
Preventive measures to avoid Ventilator-Associated Pneumonia (VAP)? 5
DVT prophylaxis
GI stress ulcer prophylaxis
Semi-recumbent positioning (HOB 30° – 45°)
Daily assessment of extubation readiness: sedation vacation and spontaneous breathing trial
Daily oral care with chlorhexidine
How do you troubleshoot common ventilator alarms and what do those alarms mean (e.g., high pressure, low pressure)?
HIGH PRESSURE - Triggered by increased resistance in the airway
LOW PRESSURE - Ventilator not receiving enough pressure. Triggered by decreased airway resistance & tidal volume
How do you prepare for intubation as the nurse? (During the intubation: Does the
provider give sedation or a paralytic first?)
SEDATION FIRST!!!! then paralytic
What are indications for suctioning your patient?
Suction only when needed
Visible sections in ET tube
Increased RR or frequent (moist) coughing
Sudden decrease in SpO2
Suspected aspiration of secretions
Increase in airway pressures noted on ventilator
Auscultating adventitious breath sounds over trachea or bronchi
Restlessness or agitation
How do we confirm placement of an endotracheal tube (ETT)?
Why do we need a swallow study post extubation?
What does stridor indicate post-extubation?
What actions are needed for these patients emergently?
Chest X-RAY
To assess for dysphagia (difficulty swallowing) and the risk of aspiration
Glottic edema/epiglottitis or upper airway edema
Racemic epi nebulizer, IV steroid, call for reintubation, RT STAT
What are the key assessment priorities post-intubation?
Priority- Assess ETT for proper placement
FIRST: auscultate both lung fields for equal
breaths while patient receives breaths via resuscitation bag
