Respiratory Pt. 2 Flashcards
What is the difference between absolute and relative shunts?
- Absolute shunt: no ventilation (increasing oxygen doesn’t help)
- Relative shunt: alveoli still partially ventilating (can improve with higher oxygen levels)
What is the criteria for hypoxemic respiratory failure?
- Conditions that prevent enough oxygen from getting into the blood, leading to hypoxemia
- Decrease in arterial O2 (PaO2) and saturation (SaO2)
- Insufficient O2 transferred to blood
- PaO2 < 60 mmHg (despite supplemental O2)
Issue: less O2 exchange between the alveoli and pulmonary capillaries
What is the criteria for hypercapnic respiratory failure?
- Conditions that make it hard to get rid of enough carbon dioxide, leading to hypercapnia
- increase in arterial CO2 (PaCO2)
- Inadequate CO2 removal
- PaCO2 > 50 mmHg
- pH < 7.35 (acidosis)
Issue: insufficient CO2 removal and the body’s inability to compensate
How do ABGs help differentiate between hypoxemic and hypercapnic respiratory failure?
- Hypoxemic: Low PaO2 (<60 mmHg), normal or low PaCO2.
- Hypercapnic: High PaCO2 (>50 mmHg), low pH (acidosis), and usually normal PaO2.
When should oxygen therapy be initiated?
- PaO2 < 60 mmHg
- SpO2 < 90%
What are the goals of oxygenation?
- Maintain PaO2 ≥ 60 mmHg or SpO2 ≥ 90%
- Correct hypoxemia/hypoxia
What are the initial manifestations of Acute Respiratory Distress (ARDS)?
- Respiratory distress
- Dyspnea (shortness of breath)
- Tachypnea (rapid breathing)
- Hypoxemia (low oxygen levels)
- Tachycardia
How does the presentation of ARDS evolve over time?
- may survive the acute phase of lung injury and recover
- some injured lungs repair and recover, but in others ARDS progresses
- patients may need several weeks of long-term mechanical ventilation
- fribrotic stage - chance of survival is low
fribrotic stage = lung tissue becomes scarred and stiff
What is the key clinical manifestation of ARDS?
severe, refractory hypoxemia
doesn’t respond to oxygen
Explain the use of prone positioning and PEEP in the management of ARDS.
- Prone positioning (face down): Helps improve V/Q mismatch and enhances oxygenation
- PEEP (Positive End-Expiratory Pressure): Keeps the lungs open to improve oxygen levels while reducing the need for high levels of O2 (prevents O2 toxicity)
How is ARDS managed with protective lung ventilation strategies?
- smaller breaths (4-8 mL/kg) to reduce lung injury
- lungs are stiffer and harder to inflate
- difficult to maintain normal CO2 levels at low pressures
- higher CO2 (permissive hypercapnia) is allowed to prevent further lung damage
uses smaller breaths to protect lungs, even if it means letting CO2 rise
How do we manage ARDS patients with nutritional needs?
- Enteral feeding/TPN (adequate nutrition)
- Albumin (maintain fluid imbalance/blood pressure)
- Watch I/Os (prevent fluid overload/dehydration)
- Psychosocial support (help emotional strain)
How do we manage ARDS patients with pharmacotherapy?
- corticosteroids and surfactant replacement (anti-inflammatory and lung protection)
- inhaled nitric oxide and beta-agonists (improve oxygenation)
- diuretics (reduce fluid buildup)
- neuromuscular blockers and sedation (ventilator support)
What are the indications for using CPAP or BiPAP?
- CPAP: sleep apnea
- BiPAP: COPD and severe respiratory distress
CPAP - uses a mask to keep air flowing into your lungs
BiPAP - gives different pressures for breathing in and out, making it easier to breathe
What are the contraindications for using CPAP or BiPAP?
- Low consciousness or lethargic
- High oxygen needs (severe failure)
- Decreased respiratory drive
- Facial trauma
- Unstable blood pressure
- Too much secretions
Under what circumstances would you consider intubation over non-invasive options?
- Acute ventilatory or oxygenation failure
- RR > 35
- Asymmetrical chest rise
- GCS score < 8
Glasgow Coma Scale = LOC
<8 indicates severe brain injury
What are priority assessments when implementing oxygen therapy?
- Changes in mental status
- Vital signs – RR and O2
- ABGs
What are the advantages of a tracheostomy?
- easier to clean
- better oral & bronchial hygiene
- more comfortable
- less risk of damaging vocal cords
What should always be at the bedside for a patient with a new tracheostomy? Why?
- Spare tracheostomy tube (in case of tube dislodgement)
- Suction equipment (clear secretions)
- O2 source (supplemental O2)
- Tracheostomy care supplies (prevent infection)
What strategies should be used to minimize ventilator-associated complications?
- elevate the head of the bed (prevent aspiration)
- oral care with chlorhexidine (reduce infection)
- sedation vacations (assess readiness for extubation)
- prevent DVTs and stress ulcers.
- frequent suctioning (clear secretions)
- hand hygiene (reduce infection risk)
How do you troubleshoot common ventilator alarms and what do those alarms mean?
- High pressure alarm: increased resistance
- clear airway, check tubing
- Low pressure alarm: decreased resistance/tidal volume
- check connections, secure tubing
always assess patient first! if cause unknown, remove from ventilator
How do you prepare for intubation as a nurse?
- Alert provider and ensure consent (unless emergency)
- Prepare resuscitation equipment (airway cart, suction)
- Call for help, explain to patient/family
- Page respiratory therapist for ventilator setup
- Check IV access and pre-oxygenate with 100% O2
- Prepare sedation and meds
During intubation, does the provider give sedation or paralytics first?
Sedation is given first, followed by paralytics to facilitate intubation
How do you confirm placement of an ETT?
- auscultating breath sounds
- capnography (measures CO2 levels)
- chest x-ray
