Chronic respiratory failure is a common medical condition characterized by the inability to maintain normal oxygen (PaO2 ≥ 60mmHg) and/or carbon dioxide (PaCO2 ≤ 45mmHg) levels. Many diseases may lead to chronic respiratory failure, including chronic obstructive pulmonary disease (COPD), thoracic restrictive diseases (TRD) such as kyphoscoliosis, neuromuscular diseases (NMD), and obesity hypoventilation.1 Associated with increased morbidity and mortality, chronic respiratory failure may range from mild to severe and may be stable or progressive.
Chronic respiratory failure with hypercapnia may be treated with chronic mechanical ventilation. Mechanical ventilator devices are broadly classified into two categories: home mechanical ventilators (HMV) and bi-level positive airway pressure (BPAP) devices. While both HMV and BPAP devices provide positive pressure ventilation, their technical features may vary and overlap considerably. Variability includes: interface (tracheostomy or mask), mode of ventilation (such as pressure targeted versus volume targeted), respiratory circuit (such as single-limb versus double-limb), monitoring capability, safety and alarm systems, and internal battery life. Devices also differ by level of oversight and servicing. In addition, certain device features (such as the ability to perform lung volume recruitment) may only be available with certain devices and settings.
If deemed to be feasible and safe, using these devices in the home setting is preferred to other settings such as intensive care units (ICUs), ventilator weaning units, or long-term care hospitals. Advantages of home use include lower costs, greater independence, increased quality of life, decreased risk of healthcare-associated infections, and reduced use of acute care facilities. The number of patients using long-term HMVs and BPAP devices in the home setting is growing.and this patient population is increasingly differentiated from patients with acute respiratory failure who use such devices in the hospital setting. In addition, the cost of caring for patients with medical conditions associated with chronic respiratory failure is also growing, with estimates as high as $50 billion annually in the United States for COPD alone.
For patients who use home mechanical ventilation through a noninvasive interface, or noninvasive positive pressure ventilation (NIPPV), selecting the optimal device type (HMV versus BPAP versus continuous positive airway pressure [CPAP]) and device settings is imperative. Depending on the severity of illness, patients with chronic hypercapnic respiratory failure may require no, intermittent, or continuous ventilatory support. Failing to adequately treat chronic respiratory failure with the appropriate device could potentially result in sudden or gradual hypoxemia and/or hypercapnia. This can lead to poor quality of life, sleepiness, hospital admission, intubation, and even respiratory arrest and death. Some patients have progressive respiratory failure and may require advanced ventilatory capabilities as their disease progresses.
Currently, substantial variability exists regarding the usage, prescribing patterns, policies, and guidelines for noninvasive HMVs, BPAPs, and CPAPs. While a number of guidelines address home use of BPAPs and HMVs, there is marked variability in the conclusions, recommendations, and evidence basis for these guidelines. With current practice and guideline variability, there is a clear need to synthesize the best available evidence to guide prescribing.
This systematic review evaluates home NIPPV in adult patients with chronic respiratory failure primarily due to chronic obstructive pulmonary disease (COPD), thoracic restrictive disorders, and neuromuscular disease. Other causes of respiratory failure were included due to additional interest.