What Happens During An Asthma Attack?

The goal of any asthma treatment program is to prevent and control asthma. Still, there may be times when your asthma gets the best of you. Here is what actually happens during an asthma attack, and why it is important to take it seriously.

Airway Inflammation. All asthmatics have some degree of airway (bronchiole) inflammation. This is due to an abnormal immune response caused by the interaction of asthma genes with certain environmental factors, which include common allergens, viral infections, obesity, poor diet, gastrointestinal reflux, air pollution, cigarette smoke, wood smoke, rapid breathing, etc. 

Asthma Severity.  The degree of inflammation determinesasthma severity: mild, moderate, or severe, and intermittent or persistent. It determines how twitchyyour airways are.

Hyperactive Airways.  Inflamed airways are over-sensitive, hypersensitive, or twitchy, when exposed to to asthma triggers. As you can probably see, I like to use the term twitchy.

Asthma Triggers. These are stimuli (things that arouse a response) in your environment that trigger the asthma response. These include common allergens, viral infections, strong emotions, gastrointestinal reflux, cold air, rapid breathing, strong smells, air pollution, cigarette smoke, wood smoke, etc.

Abnormal Immune Response. This is what begins the asthma response. Your immune system recognizes asthma triggers as harmful, and initiates a full out onslaught on them. Various chemical reactions occur, including the release of inflammatory markers called histamine and leukotrienes from mast cells lining airways.

Worsening inflammation. This causes underlying airway inflammation to worsen, making airways twitchy. This causes a tickly feeling inside your chest, chest pressure, chest tightness, or chest pain. This ultimately leads to mucus hypersecretion and bronchospasm. The goal of this is to trap and kill, pathogens, although in our case this response is not needed.

Mucus Hypersecretion.  Asthmatics have an abnormally large amount of goblet cells (cells that make sputum), making them prone to developing excessive secretions (sputum) just prior to or during acute asthma episodes. It may result in throat clearing, spitting up phlegm, and coughing. These are all early warning signs of asthma.

Bronchospasm. Worsening airway inflammation causes the muscles wrapped around airways (bronchiolar muscles) to spasm, constrict, and squeeze airways.

Airflow Obstruction.  The combination of bronchospasm and mucus hypersecretion creates airway obstructions, or narrowed airways.

Wheeze. This is the sound air makes as it passes through narrowed airways. It is heard during an acute (it’s happening now) asthma attack. Please note here that some asthmatics do not wheeze.

Increased Airway Resistance. Obstructed airways act as a barrier that resists, or acts to prevent, the flow of air out of the airways (meaning, during exhalation).

Airflow Limitation. This increased resistance thereby slows the movement of air during exhalation.  This makes it so that you can take in air, although your exhalation is prolonged. Your next breath may come before exhalation is complete.

Air Trapping.  When the next breath comes before the current breath is complete, this causes air to become trapped inside your chest. When you inhale, it may feel like you can’t take in a complete breath.

Dyspnea. The feeling you can’t catch your breath, or shortness of breath, is a tell tale symptom of an acute (it's happening now) asthma episode.

Barrel Chest. When you cannot exhale completely, air can become trapped inside your chest to the point it is fully expanded, thereby giving the appearance of a barrel. This occurs when your lungs or over-inflated with air, making your chest appear to be larger than normal (over expanded). 

Hunched Shoulders.  Your shoulders will be elevated as high as you can get them, completing the picture of barrel chest. This is done in an effort to create more room to suck in air. It is a classic sign that the asthma episode is severe.

Leaning on things to breathe. This is done in an attempt to keep the shoulders as high as possible in order to create room for more air. This also completes the picture of barrel chest, and is another classic sign of a severe asthma episode.

Mucus Plugging.  Excessive mucus may plug the smaller airways, and this creates even more resistance to breathing.²

Accessory Muscles. These are muscles that are not normally used for breathing, and most are used to assist with inhalation. When your intercostal muscles and diaphragm need assistance getting air through obstructed and narrowed airways due to increased resistance, these muscles are used. They are used in an effort to suck more air into your chest. Once you recover from your asthma attack, your chest may feel sore and stiff, and it is because you used these muscles. They hurt for the same reason that your muscles hurt following a good workout, because microscopic tears occur in muscle fibers. This is normal, and the soreness will go away in a few days.^{3, 4}

Paradoxical Breathing.  You can always tell when someone has increased airway resistance because they will use their accessory muscles to breathe. In children, because they have more flexible chests, it causes their chest to retract, or cave in, during inspiration. The chest caves in and the stomach goes out during inspiration . In adults, retractions may occur, although they are less prominent. What is usually observed in adults is the stomach being sucked in during inspiration, and out during exhalation. In either case, these are signs of paradoxical breathing due to increased airway resistance.^{3, 4, 6}

Absence of wheezing. This can sometimes be an indicator of severe airflow obstruction and limitation, especially when in the presence of paradoxical breathing, leaning on things to breathe, and talking in short, choppy sentences. Rather than hearing the the flow of air, lung sounds may appear as diminished, or absent. This is not a good sign.

Status Asthmaticus. This is when the asthma attack becomes so severe that it does not respond to treatment, and therefore becomes prolonged.

Asthma Control and Prevention.  Asthma is a chronic syndrome, meaning you will always have it. However, a neat thing about asthma is acute asthma episodes are either completely or partially reversible with treatment.⁵ They may also be prevented, or at least made less severe, by working with your asthma doctor to develop anasthma management program tailored specifically to your individual needs. It’s also a good idea to work with your doctor to develop an asthma action plan to help you decide what actions to take when you observe your early, acute, or severe asthma symptoms and signs.