The “seesaw sign,” formally known as paradoxical breathing, is a visual sign of severe respiratory distress. It represents an abnormal pattern where the chest and abdomen move in opposite directions during the respiratory cycle. This indicates the body is struggling to move air effectively. This unusual motion suggests that the primary breathing muscles are failing or working against a major obstruction or mechanical failure. Recognizing this sign is crucial because it often precedes respiratory failure, a life-threatening condition requiring immediate medical intervention.
What the Seesaw Sign Looks Like
The seesaw sign is a clear, visible reversal of the body’s normal breathing motion. During healthy inhalation, the chest and abdomen both expand outward as the lungs fill with air. In paradoxical breathing, the chest wall visibly sinks inward while the abdomen simultaneously pushes outward during the attempt to inhale. This opposing motion resembles the action of a playground seesaw, which is how the sign gets its common name. The movement then reverses during exhalation: the chest moves outward while the abdomen sinks back in.
The Physiological Explanation
Normal breathing is primarily driven by the diaphragm, a dome-shaped muscle beneath the lungs. When the diaphragm contracts, it moves downward, increasing the volume of the chest cavity and creating a strong negative pressure that draws air into the lungs. This downward movement also displaces the abdominal contents, causing the belly to expand outward.
The seesaw pattern occurs when the diaphragm is weak or fatigued, or when the resistance to airflow is extremely high. During severe respiratory distress, the patient attempts to overcome this resistance by generating immense negative pressure inside the chest cavity. If the diaphragm is weak or the chest wall is unstable, this powerful negative pressure sucks the chest wall inward instead of allowing it to expand. The chest is pulled in by the vacuum created by the failed inspiratory effort, while the diaphragm still attempts to contract and push the abdomen out. This mechanical disconnect between the chest and abdomen indicates that the respiratory pump is struggling and gas exchange is impaired.
Common Causes of Paradoxical Breathing
The underlying causes for the seesaw sign are conditions that lead to severe respiratory muscle fatigue or major mechanical failure of the chest wall. One immediate mechanical cause is flail chest, which results from blunt trauma where multiple adjacent ribs are broken in more than one place. This creates an unstable segment of the chest wall that moves independently.
Neuromuscular disorders can also lead to this pattern by weakening or paralyzing the diaphragm and other respiratory muscles. Conditions like Guillain-Barré syndrome or advanced muscular dystrophy disrupt the nerve signals that coordinate muscle movement, resulting in diaphragmatic dysfunction.
Severe respiratory illnesses, such as advanced Chronic Obstructive Pulmonary Disease (COPD) exacerbations, severe asthma attacks, or bronchiolitis in infants, can cause profound muscle exhaustion. The constant, strenuous effort to breathe against blocked airways eventually leads to the fatigue of the intercostal muscles, causing the chest to collapse inward during inspiration.
Immediate Medical Assessment and Care
The appearance of the seesaw sign always signals a medical emergency and requires immediate professional attention. This visible struggle means the body is on the verge of, or has already entered, respiratory failure. The first step is to contact emergency services right away.
While waiting for help, initial assessment involves checking the person’s level of consciousness and observing the rate and depth of their breathing. Medical professionals will rapidly assess oxygen saturation using a pulse oximeter and check other vital signs. Stabilization begins with providing supplemental oxygen to compensate for the ineffective air exchange. Depending on the severity, the patient may require non-invasive support, such as continuous positive airway pressure, or invasive mechanical ventilation to take over the work of breathing. Definitive care involves identifying and treating the underlying cause, such as relieving an airway obstruction, stabilizing a traumatic chest injury, or managing a neurological crisis.