Acute Respiratory Failure Overview

Study Notes

Acute Respiratory Failure (ARF)

ARF is a common critical care disorder where the lungs can't adequately exchange oxygen and remove carbon dioxide.
Severe ARF often involves acute lung injury (ALI) or acute respiratory distress syndrome (ARDS), marked by diffuse alveolar damage and profound hypoxia.
Respiratory function has two key components: ventilation (physical air movement) and respiration (gas exchange).
Disruption in either process can lead to respiratory failure.

Types of Respiratory Failure

Type I (Hypoxemic Failure): Impaired oxygen transport from alveoli to arterial flow.
- Causes include pneumonia, pulmonary edema, ARDS, aspiration, and atelectasis.
- Related to Impaired Gas Exchange nursing diagnosis.
Type II (Hypoxemic Hypercapneic Failure): Musculoskeletal or anatomical lung dysfunction causing inadequate ventilation.
- Causes include COPD, neurological issues (narcotics, head injury), muscle weakness, or skeletal abnormalities.
- Results in CO2 buildup (hypercapnea) and reduced oxygenation (hypoxemia).

Oxygen Therapy Devices

Nasal Cannula (Nasal prongs): Low-flow, comfortable, up to 6 LPM, but FiO2 quantification can be inaccurate.
Simple Mask: Higher FiO2 (8-12 LPM), but FiO2 calculation is also affected by breathing patterns.
High-Flow Oxygen Therapy: Delivers higher flow than patient's inspiratory rate; mixes with room air; may have positive pressure, oxygen reservoir. Used with nasal cannula, pillow, or face mask.

Mechanical Ventilation

Mechanical ventilation supports breathing for patients unable to ventilate independently.
Can be non-invasive or invasive.
Noninvasive ventilation (NIV) aims to improve oxygenation and decrease CO2 levels (using methods like BiPAP).
- Effects on gas exchange are seen within 15 minutes from ABGs.
Invasive ventilation uses positive pressure devices through tubes (nasotracheal, endotracheal, or tracheostomy) to maintain a patent airway.
Intubation (insertion of ET/NT tube) requires monitoring oxygenation and cardiovascular health.

Desired Outcomes of Mechanical Ventilation

Symptom relief
Muscle rest
Reduced work of breathing
Improved oxygenation
Improved ventilation
Acid-base balance restoration
Chest wall stabilization
Sedation/anesthesia provision

Description

This quiz covers the essential aspects of Acute Respiratory Failure (ARF), including its types and underlying causes. Understanding ARF is crucial for critical care, as it directly impacts ventilation and gas exchange. Test your knowledge on hypoxemic and hypercapnic respiratory failure.