Mechanical Ventilation Flashcards

Flashcards covering key concepts related to establishing the need for mechanical ventilation, including respiratory failure, assessment parameters, and indications for different ventilation methods.

What is the primary purpose of mechanical ventilation?

To maintain homeostasis by ensuring adequate gas exchange and acid-base balance.

List four objectives of mechanical ventilation.

Support gas exchange, increase lung volume, reduce work of breathing, reverse respiratory failure

List four assessments to determine if a patient is in respiratory distress.

Level of consciousness, work of breathing, skin appearance, vital signs.

What are the clinical criteria for defining Acute Respiratory Failure (ARF)?

PaO2 below predicted normal, PaCO2 greater than 50 mm Hg and rising, pH of 7.25 or lower.

What condition is associated with acute life-threatening tissue hypoxia?

Hypoxemic Respiratory Failure

What condition is associated with person cannot achieve adequate ventilation to maintain a normal PaCO2?

Hypercapnic Respiratory Failure

Name three causes of hypoxemic respiratory failure.

V/Q mismatch, diffusion defects, right-to-left shunting.

What does hypercapnic respiratory failure result from?

Ventilatory pump failure (respiratory muscles, thoracic cage, and nerves controlled by respiratory centers).

When recognizing hypoxemia, what are mild to moderate signs?

Tachypnea, dyspnea, paleness, tachycardia, mild HTN, restlessness, disorientation, headaches, lethargy

When recognizing hypoxemia, what are severe signs?

Tachypnea, dyspnea, cyanosis, bradycardia, hypotension, somnolence, confusion, blurred vision, loss of consciousness, coma.

What are mild to moderate signs when recognizing hypercapnia?

Tachypnea, dyspnea, tachycardia, HTN, vasodilation, headaches, drowsiness, dizziness, confusion, sweating skin redness.

What are severe signs when recognizing hypercapnia?

Tachypnea (eventually bradypnea), eventually hypotension, hallucinations, hypomania, convulsions, loss of consciousness, eventually coma.

Name 3 disorders that could be associated with Possible Respiratory Failure due to a Reduced Drive to Breathe.

Depressant drugs, brain/brainstem lesions, Hypothyroidism

Name 3 disorders that could be associated with Possible Respiratory Failure due to a Increased Drive to Breathe.

Increased metabolic rate, Metabolic acidosis, Anxiety associated with dyspnea

Name two disorders associated with possible respiratory failure: Neuromuscular Disorders.

Paralytic disorders, Impaired muscle function

Name 3 disorders that increase the Work of Breathing.

Pleura-occupying lesions, Chest wall deformities, Increased airway resistance

What does MIP (Maximum inspiratory pressure) measure?

Respiratory Muscle Strength

What is the normal value for MIP?

-50 to -100 cmH2O

What threshold values are commonly cited for MIP?

−20 to −30 cm H2O or less (i.e., 0 to −20 cm H2O) and a VC lower than 10 to 15 mL/kg.

What does Vital Capacity assess?

Respiratory muscle strength in patients with neuromuscular disease

What is typically the normal value for Vital Capacity?

65 to 75 mL/kg of Ideal Body Weight (IBW); can be as high as 100 mL/kg IBW

What does PEF determine, and what are acceptable values?

PEF is a good indicator of airway resistance and a patient’s ability to maintain airway patency; Acceptable values range from 350 to 600 L/min

What is the normal RR in adults?

12 to 20 breaths/min

What product makes up Minute Ventilation, and what is the normal value?

(Ve = RR x Vt); Normal value is about 5 to 6 L/min

What is the best single indicator of adequate ventilation?

PaCO2

List two key indicators of refractory hypoxemia respiratory failure.

PaO2 < 70mmHg or SpO2 < 90%) on oxygen with FiO2 > 0.6

What are the standard criteria for initiating Mechanical Ventilation

Apnea or absence of breathing, Acute ventilatory failure, Impending ventilatory failure, Refractory hypoxemic respiratory failure with increased work of breathing or an ineffective breathing pattern

Give an indication for Invasive Mechanical Ventilation in Adults with ARF.

Acute exacerbation of chronic obstructive pulmonary disease (COPD)

What are some alternatives to Invasive Ventilation?

Non-invasive positive pressure ventilation (NIV), Heated High Flow Oxygen Therapy

List 4 Absolute Contraindications for NIV.

Respiratory arrest, Cardiac arrest, Cardiovascular instability, Nonrespiratory organ failure

List 3 scenarios when NIV should be changed to Invasive.

Respiratory arrest, Respiratory rate >35 breaths/min, Life-threatening hypoxemia