Normal breathing is quiet and effortless, requiring no conscious thought. Increased respiratory effort, often called work of breathing, occurs when the body must use additional muscles and significantly more energy to move air into the lungs. This heightened effort serves as a visible and audible signal that the body is struggling to maintain adequate oxygen intake or carbon dioxide removal. Recognizing these signs quickly indicates a serious medical situation where the body is working harder than it can safely sustain to overcome airway resistance or lung stiffness.
Visible Physical Signs
One of the most apparent indicators of increased effort is retractions, the inward pulling of soft tissues during inhalation. This happens because a narrowed or blocked airway forces the diaphragm and chest muscles to create greater negative pressure inside the chest cavity to draw air in. This suction effect pulls the compliant skin and muscle inward.
Retractions are classified by where they occur on the body, with the location potentially suggesting the area of obstruction. Upper airway obstructions often cause retractions higher on the body. These signs demonstrate the body’s reliance on accessory muscles, such as those in the neck and shoulders, which are not typically used during resting respiration.
Types of Retractions
- Intercostal retractions involve the skin sinking in between the ribs.
- Subcostal retractions appear just below the rib cage.
- Substernal retraction is the skin pulling in below the breastbone.
- Suprasternal retractions occur in the notch above the breastbone.
- Supraclavicular retractions appear above the collarbones.
Nasal flaring, the widening of the nostrils with each breath, is another observable sign, representing an attempt to decrease resistance and draw more air through the nose.
A head bobbing motion, where the head moves forward with each inhalation, is often observed in infants. This results from the heavy recruitment of neck muscles to assist breathing. A rocking or seesaw motion can also be seen, where the chest sinks as the abdomen rises during inhalation, indicating extreme respiratory muscle fatigue.
Audible Indicators of Distress
Abnormal sounds indicate the body is working harder to breathe. Grunting is a distinct sound heard primarily on exhalation, which is the body’s attempt to generate its own positive pressure. The person partially closes the glottis (vocal cord opening) and exhales against it to maintain positive end-expiratory pressure (PEEP). This mechanism keeps the small air sacs (alveoli) open longer, improving oxygen exchange.
Wheezing is a high-pitched, whistling sound typically heard when breathing out. It is caused by air passing through narrowed lower airways, such as the bronchioles, often seen in asthma. Stridor is a harsh, high-pitched noise heard most often when breathing in, suggesting a blockage or narrowing high up in the upper airway, such as the larynx or trachea.
The subjective sensation of “air hunger” is an intense urge to breathe, often described as gasping or a feeling of suffocation. The resulting rapid, shallow breathing is a behavioral response to the brain signaling that oxygen needs are not being met.
Changes in Breathing Rate and Systemic Signs
An altered breathing rate is a measurable sign that the body is trying to compensate for a lack of oxygen. Tachypnea, or rapid breathing, is often the first compensatory mechanism, increasing the number of breaths per minute to boost overall ventilation. Normal resting rates vary: adults average 12 to 20 breaths per minute, while infants typically breathe 30 to 60 times per minute.
Rates significantly above these benchmarks indicate compensation. Conversely, a slow or absent rate, called bradypnea, suggests impending respiratory failure. Bradypnea indicates that respiratory muscles are fatigued and can no longer sustain the high effort, leading to a decline in oxygen levels.
Systemic signs reflect the body’s overall response to poor oxygenation. Cyanosis, a bluish or grayish tint to the skin, is a physical manifestation of low oxygen levels in the blood. This color change is most easily observed in areas like the lips, nail beds, and mucous membranes. Paleness (pallor) is also common, indicating poor circulation that accompanies respiratory distress.
A change in mental status is a systemic red flag, as the brain is highly sensitive to oxygen deprivation. This can manifest as anxiety, restlessness, or irritability in earlier stages, but can quickly progress to confusion, lethargy, or unresponsiveness as oxygen levels fall.
Immediate Action: When to Seek Emergency Care
Any sign of increased respiratory effort, especially when occurring at rest, requires prompt medical attention. Specific signs mandate an immediate call to emergency services, as they indicate severe or rapidly worsening distress.
These red flags include any blue or gray color change around the mouth or fingernails, signaling critically low blood oxygen. The inability to speak or cry due to the effort of breathing, or a sudden silence after a noticeable struggle, should be treated as an emergency. Any significant change in responsiveness, such as becoming limp, drowsy, or difficult to rouse, signals that the brain is being deprived of oxygen. While waiting for help, position the individual to maximize comfort and ease of breathing, such as sitting upright and leaning forward slightly.