Mechanical Vent Chapter 4- Establishing the need for mechanical ventilation

Flashcards based on lecture notes about Mechanical Ventilation, covering assessment, respiratory failure, physiological measures, and objectives of mechanical ventilation.

How can you primarily assess a patient in respiratory distress?

Physical examination, patient history and diagnosis, and physiologic indicators, often starting from the doorway.

What are the key aspects of physical examination when assessing a patient in respiratory distress?

Level of consciousness, skin color and appearance, vital signs (HR, BP, respirations, breath sounds, SpO2), and mental status.

What historical information is important to gather from a patient in respiratory distress?

Patient's PMH (Past Medical History) and diagnosis, pre-existing pulmonary or neuromuscular diseases, and any traumatic injuries to the head or spine.

Define Acute Respiratory Failure (ARF)

Respiratory activity that is absent or insufficient at removing CO2 and picking up O2, leading to an inability to maintain acceptable PaO2, PaCO2, and pH levels.

What are the typical blood gas values in respiratory failure?

PaO2 < 70 on > 0.6 FiO2, PaCO2 > 55 and rising, pH < 7.25.

List the two types of respiratory failure

Hypoxic respiratory failure and Hypercapnic respiratory failure.

What are potential treatments for hypoxic respiratory failure besides mechanical ventilation?

O2 therapy and/or CPAP.

List causes of hypercapnic respiratory failure

CNS, neuromuscular, and increased work of breathing (WOB) disorders.

Why is hypercapnic respiratory failure also called Ventilatory Pump Failure?

Reflects the body's inability to maintain normal PaCO2 levels due to issues with the respiratory 'pump' mechanisms.

How do CNS disorders typically cause hypercapnic respiratory failure?

By causing hypoventilation.

How can paralytic disorders lead to hypercapnic respiratory failure?

By impairing the muscles necessary for breathing.

How do increased airway resistance, bronchospasm, mucosal edema, or airway inflammation impact WOB?

Increases the work of breathing, potentially leading to hypercapnic respiratory failure.

What does MIP (Maximum Inspiratory Pressure), or NIF, measure?

The maximum amount of negative pressure a patient can generate during an inspiratory effort, indicating the strength of their inspiratory muscles.

What does VC (Vital Capacity) measure?

Maximum inspiration followed by maximum expiration, indicating a patient's ability to generate a significant cough.

What does PEFR (Peak Expiratory Flow Rate) indicate?

A patient’s ability to maintain adequate airway patency.

What PaCO2 level is the best indicator of adequate ventilation?

35-45

How is increased dead space characterized?

VD/VT ratio > 0.4. Dead space is an area that is ventilated but not perfused.

What is a good indicator of a patient's total oxygen carrying capacity?

CaO2 (Arterial Oxygen Content)

List the Physiological objectives of Mechanical Ventilation

To support or manipulate pulmonary gas exchange, increase lung volume, and reduce the work of breathing.

List the Clinical objectives of Mechanical Ventilation

Reverse acute respiratory failure, reverse respiratory distress, reverse hypoxemia, prevent or reverse atelectasis, reverse ventilatory muscle fatigue, permit sedation and/or paralysis, reduce systemic or myocardial oxygen consumption, reduce intracranial pressure, and stabilize the chest wall.

List the Criteria for Mechanical Ventilation

Apnea or absence of breathing/airway protection, Acute Respiratory Failure, Impending Respiratory Failure, Refractory hypoxic Respiratory Failure with increased WOB and acute exacerbation of COPD with complicating factors