From the Guidelines
Yes, a patient can have decompensated type 2 respiratory failure, which is characterized by inadequate ventilation leading to hypercapnia and hypoxemia, and requires prompt treatment to prevent further deterioration and improve outcomes in terms of morbidity, mortality, and quality of life. Type 2 respiratory failure, as defined by the British Thoracic Society, occurs when there is a PaCO2 above the normal range of 4.6–6.1 kPa and patients with hypercapnia are said to have type 2 respiratory failure even if the oxygen saturation is in the normal range 1. Decompensated type 2 respiratory failure typically happens when CO2 levels rise significantly, overwhelming the kidneys' ability to retain bicarbonate to buffer the acidity, and can be caused by severe COPD exacerbations, neuromuscular disorders, opioid overdose, or chest wall deformities.
Some key points to consider in the management of decompensated type 2 respiratory failure include:
- The use of non-invasive ventilation (NIV) like BiPAP, with typical initial settings of IPAP 12-16 cmH2O and EPAP 4-6 cmH2O, or mechanical ventilation in severe cases, as recommended by the BTS/ICS guideline for the ventilatory management of acute hypercapnic respiratory failure in adults 1.
- Careful titration of supplemental oxygen to maintain oxygen saturation between 88-92% in COPD patients to avoid suppressing respiratory drive, as suggested by the BTS/ICS guideline 1.
- The importance of addressing the underlying cause of the respiratory failure, such as COPD exacerbations, and providing optimal medical care, including bronchodilators, corticosteroids, and antibiotics as needed, to improve morbidity, mortality, and quality of life outcomes.
It is essential to note that the definition of hypercapnia and the threshold for initiating NIV have evolved over time, with the BTS/ICS guideline recommending that NIV be started when a pH <7.35, a PaCO2 of ≥6.5 kPa, and RR >23 breaths/min persists or develops after an hour of optimal medical therapy 1. By prioritizing the management of decompensated type 2 respiratory failure and following the latest guidelines and evidence-based recommendations, healthcare providers can improve patient outcomes and reduce the risk of morbidity and mortality.
From the Research
Definition of Decompensated Type 2 Respiratory Failure
Decompensated type 2 respiratory failure refers to a condition where the body's ability to compensate for impaired gas exchange is overwhelmed, leading to severe hypercapnia (elevated CO2 levels) and hypoxemia (low oxygen levels) 2.
Causes and Associations
Decompensated type 2 respiratory failure can occur in patients with chronic obstructive pulmonary disease (COPD) 3, as well as in those with other underlying respiratory conditions. It is often associated with acute exacerbations of COPD 4, and can be precipitated by factors such as infection, air pollution, or other environmental stressors.
Key Characteristics
Key characteristics of decompensated type 2 respiratory failure include:
- Severe hypercapnia (PaCO2 > 50mmHg) 3
- Hypoxemia (PaO2 < 60mmHg) 2
- Acidosis (pH < 7.35) 4
- Increased respiratory rate and work of breathing 5
Patient Phenotype and Risk Factors
Patients with decompensated type 2 respiratory failure often have underlying chronic respiratory disease, such as COPD 3. Other risk factors include:
- Frequent exacerbations of COPD 3
- High BODE index 6
- Low FEV1% 6
- Previous use of non-invasive ventilation (NIV) 6
Clinical Implications
Decompensated type 2 respiratory failure is a serious condition that requires prompt medical attention. Patients with this condition are at high risk of life-threatening events, including respiratory arrest and cardiac arrest 6. Early recognition and treatment of decompensated type 2 respiratory failure are critical to improving outcomes and reducing morbidity and mortality 5.