Does an asthmatic patient exhibit tachypnea (rapid breathing) or bradypnea (slow breathing)?

From the Guidelines

Asthmatic patients typically experience tachypnea, characterized by a respiratory rate greater than 25 breaths per minute, as indicated in the guidelines for the management of asthma 1. During an asthma attack, inflammation and bronchoconstriction narrow the airways, making it difficult to move air in and out of the lungs. The body compensates for this reduced airflow by increasing the respiratory rate, resulting in tachypnea. This faster breathing is an attempt to maintain adequate oxygen levels and expel carbon dioxide despite the airway obstruction. Some key features of severe asthma include:

• Respirations >25/min
• Pulse >110 beats/min
• Bradycardia or hypotension
• Exhaustion, confusion, or coma, as outlined in the guidelines 1. However, it's essential to note that bradypnea (abnormally slow breathing) can occur in severe cases, indicating severe respiratory fatigue or impending respiratory failure, and requires immediate medical attention. The pathophysiology of asthma involves a complex interplay of airway inflammation, bronchoconstriction, and hyperresponsiveness, leading to variable and recurring symptoms, airflow obstruction, and an underlying inflammation, as described in the expert panel report 3 (EPR-3) guidelines for the diagnosis and management of asthma 1. In terms of management, rescue medications like albuterol (a short-acting beta-agonist) can help reduce tachypnea by relaxing the bronchial smooth muscles to open airways. Overall, tachypnea is a common symptom of asthma, and its management is crucial to prevent severe complications and improve quality of life for patients with asthma.

From the Research

Asthmatic Patient Respiratory Rate

• Asthmatic patients often experience respiratory symptoms during acute attacks, including changes in breathing rate.
• Studies have shown that asthmatic patients tend to hyperventilate during acute attacks, with an increased respiratory rate 2.
• The respiratory rate in asthmatic patients is often correlated with spirometric measures of airflow obstruction, such as peak expiratory flow rate and forced expired volume in one second 2.
• In acute severe episodes of asthma, patients typically exhibit tachypnea, with a respiratory frequency ranging from 25 to 28 breaths per minute 3.

Tachypnea vs Bradynea

• Tachypnea, or rapid breathing, is a common symptom of acute asthma, whereas bradynea, or slow breathing, is not typically associated with asthma exacerbations 2, 3.
• The increased respiratory rate in asthmatic patients is thought to be a response to airways obstruction and hypoxia, rather than a primary cause of the disease 2.
• While some studies have reported variable breathing patterns in asthmatic patients, including both rapid and deep breathing, tachypnea is generally considered a characteristic feature of acute asthma 2, 3.

Clinical Correlates

• The clinical presentation of asthma, including symptoms and signs such as wheezing, dyspnea, and cough, is often associated with physiologic abnormalities, including airways obstruction and hyperinflation of the thorax 3.
• The severity of asthma exacerbations can be assessed using various clinical and physiologic measures, including respiratory rate, peak expiratory flow rate, and forced expired volume in one second 4, 5, 6.
• Monitoring respiratory rate and other clinical correlates can be useful in assessing disease activity and response to therapy in asthmatic patients 6, 2, 3.