From the Guidelines
The normal respiratory waveform is characterized by a smooth, rhythmic pattern with an inspiratory phase of about 1-1.5 seconds and an expiratory phase of 2-3 seconds, resulting in an inspiration-to-expiration (I:E) ratio of approximately 1:2, as observed in healthy subjects with normal forced oscillation technique (FOT) indices 1. In healthy individuals, the respiratory rate typically ranges from 12-20 breaths per minute, with each breath having approximately equal depth and duration. The waveform should show consistent amplitude, representing adequate tidal volume (approximately 500mL in adults during normal breathing). There should be no significant pauses between breaths except for normal, brief end-expiratory pauses. This regular pattern reflects proper functioning of the respiratory control centers in the brainstem, intact respiratory muscles, and normal airway resistance, as indicated by normal values of Rrs and Xrs in healthy subjects 1. Deviations from this pattern, such as irregular intervals, abnormal I:E ratios, or changes in amplitude, may indicate respiratory distress, neuromuscular disorders, airway obstruction, or other pathological conditions affecting the respiratory system, which can be detected by changes in FOT indices, such as an increase in Rrs, especially in the lower frequency range, and a decrease in Xrs, associated with an increase in fres 1. For example, in adult patients with intrapulmonary airway obstruction, Rrs is increased at the lower frequencies and falls with increasing frequency, as shown in studies using FOT indices 1. Therefore, monitoring respiratory waveforms and FOT indices can provide valuable insights into respiratory function and help diagnose and manage various respiratory conditions.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Normal Respiratory Waveform
- A normal respiratory waveform is typically characterized by a regular and rhythmic pattern of breathing, with a normal breathing frequency, depth, and effort 2.
- The normal breathing frequency for an adult is typically between 12-20 breaths per minute, with a normal minute ventilation of approximately 6-8 liters per minute 2.
- Monitoring respiratory values such as breathing frequency, pattern, and effort is crucial in identifying impending respiratory failure and guiding treatment decisions 2.
Factors Affecting Respiratory Waveform
- Respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD) can affect the respiratory waveform, leading to abnormal patterns of breathing 3, 4, 5.
- Treatment with oxygen, bronchodilators, and corticosteroids can help alleviate symptoms and improve respiratory function in patients with respiratory diseases 3, 4, 5.
- Non-invasive positive pressure ventilation (NIPPV) has been shown to be safe and effective in treating respiratory distress due to acute pulmonary edema, bronchospasm, and other conditions 3.
Clinical Assessment and Monitoring
- Accurate monitoring and interpretation of respiratory values is essential in identifying early signs of respiratory failure and guiding treatment decisions 2.
- Clinicians should use a combination of clinical assessment skills and technology to monitor respiratory values and improve patient safety and outcomes 2.
- Education and improved technology are needed to reestablish the clinical potential of breathing frequency and other respiratory values in the clinical setting 2.