What are the distinguishing signs and symptoms between a mild to moderate asthma (asthma) exacerbation and a life-threatening asthma attack?

From the Guidelines

Distinguishing between mild to moderate and life-threatening asthma attacks is crucial, with life-threatening attacks characterized by severe breathlessness, inability to speak in full sentences, respiratory rate over 30 breaths per minute, heart rate over 120 beats per minute, oxygen saturation below 90%, and peak flow less than 50% of personal best, as outlined in the most recent guidelines 1. The key signs and symptoms that distinguish a mild to moderate asthma exacerbation from a life-threatening asthma attack include:

• Respiratory rate: less than 30 breaths per minute in mild to moderate attacks, and over 30 breaths per minute in life-threatening attacks
• Heart rate: less than 120 beats per minute in mild to moderate attacks, and over 120 beats per minute in life-threatening attacks
• Oxygen saturation: above 90-92% in mild to moderate attacks, and below 90% in life-threatening attacks
• Peak expiratory flow: 50-80% of personal best in mild to moderate attacks, and less than 50% of personal best in life-threatening attacks
• Ability to speak: full sentences in mild to moderate attacks, and only a few words at a time in life-threatening attacks
• Posture: no hunched-forward posture in mild to moderate attacks, and adoption of a hunched-forward posture in life-threatening attacks
• Accessory muscle use: no use of accessory muscles in mild to moderate attacks, and use of accessory muscles in life-threatening attacks
• Additional danger signs in life-threatening attacks include confusion, drowsiness, silent chest, cyanosis, and paradoxical thoracoabdominal movement, as highlighted in the guidelines 1. It is essential to note that the management of asthma exacerbations should be guided by the severity of the attack, with life-threatening attacks requiring immediate treatment and close monitoring, as recommended by the National Asthma Education and Prevention Program Expert Panel Report 3 guidelines for the management of asthma exacerbations 1.

From the Research

Distinguishing Signs and Symptoms

The distinguishing signs and symptoms between a mild to moderate asthma exacerbation and a life-threatening asthma attack can be identified through various clinical assessments and measures.

• Clinical asthma scores (CAS) have been developed to assess the severity of an asthma exacerbation, and the adoption of CAS and asthma guidelines can help identify patients with more severe asthma 2.
• Factors such as lack of response to aggressive therapy or hypoxia on initial presentation can indicate a more severe asthma exacerbation 2.
• Measures of lung function, such as peak expiratory flow (PEF), forced vital capacity (FVC), and forced expiratory volume in one second (FEV1) percent of predicted, can help assess the severity of an asthma exacerbation 3.
• Early response to treatment, measured by the percent variation of FEV1 at 30 minutes over baseline value, can be a reliable assessment of acute adult asthma and predict patient outcome 3.

Assessment of Acute Asthma

The assessment of acute asthma in the emergency department can involve various clinical and objective measures, including:

• Age, duration of attack, heart rate, respiratory rate, PEF, FVC, FEV1 percent of predicted, accessory-muscle use, dyspnea, wheezing, steroid use, and early response to treatment 3.
• Factor analysis can help identify separate and distinct dimensions of asthma, including lung function, respiratory rate, accessory-muscle use, dyspnea, heart rate, wheezing, and age, duration of attack, and steroid use 3.

Treatment of Acute Severe Asthma

The treatment of acute severe asthma can involve various delivery methods, including:

• Inhaled albuterol delivered via jet nebulizer, metered dose inhaler with spacer, or dry powder 4.
• A fixed-dose combination of albuterol and budesonide as rescue medication can reduce the risk of severe asthma exacerbation 5.
• Inhaled corticosteroids and long-acting β2-agonists can be effective in patients for whom inhaled corticosteroids alone are insufficient 6.

Management of Persistent Asthma

The management of persistent asthma requires:

• Avoidance of aggravating environmental factors 6.
• Use of short-acting β2-agonists for rapid relief of symptoms 6.
• Daily use of inhaled corticosteroids 6.
• Consideration of additional treatment, including injectable biologic agents, for patients with severe asthma 6.