Syncope is the medical term for the sudden, involuntary loss of consciousness, or fainting. For some individuals, this temporary blackout is accompanied by the loss of bladder or bowel control, known as syncopal incontinence. While distressing, this is a recognized medical occurrence associated with common forms of fainting. Understanding the physiological reason helps demystify the event and guides appropriate treatment.
Why Syncope Can Lead to Incontinence
Syncope occurs due to a sudden, brief drop in blood flow to the brain, a state called cerebral hypoperfusion. The nervous system, which regulates heart rate and blood pressure, sometimes overreacts to triggers, causing a vasovagal episode. During this episode, the heart rate slows and blood vessels in the lower body widen, causing blood to pool in the legs.
This pooling lowers blood pressure, reducing the supply of oxygen-rich blood reaching the brain. The brain, temporarily starved of oxygen, initiates a protective shutdown, resulting in the loss of consciousness. This neurological disruption extends to the brain centers that maintain muscle tone, including the sphincter muscles that keep the bowels and bladder closed.
The relaxation of these sphincter muscles causes the involuntary release of waste. This loss of control is transient and resolves once consciousness is regained and normal blood flow to the brain is restored.
Differentiating Fainting (Syncope) from Seizures
Incontinence during a loss of consciousness often raises concern about a seizure, making medical distinction important. While both syncope and seizures involve a loss of bodily control, their underlying causes differ. Syncope results from a temporary circulatory problem—a drop in blood flow to the brain—while a seizure is caused by abnormal electrical activity within the brain.
A primary difference is the duration of unconsciousness and the recovery phase. Fainting is typically brief, lasting seconds to a minute, with rapid recovery of awareness once the person is lying down. Seizures often last longer and are followed by a prolonged period of confusion, drowsiness, or fatigue, known as the postictal state.
Muscle movements also provide clues. Syncope can sometimes involve brief, irregular muscle jerks (convulsive syncope). Seizure movements, however, are typically more rhythmic, sustained, and involve tonic-clonic activity (stiffening and jerking of the limbs). Tongue biting, especially injury to the side of the tongue, is a strong indicator of a seizure.
Identifying Common Triggers
Identifying the circumstances preceding a fainting episode is crucial, as syncope is often triggered by specific situational or physiological events. Vasovagal syncope, the most common type, involves the nervous system overreacting to external stimuli. Emotional triggers include intense fear, severe pain, or the sight of blood or medical procedures like injections.
Other triggers relate to the physical environment or body state, such as standing still for prolonged periods, being in a hot or crowded area, or dehydration. Situational syncope occurs during bodily functions involving straining or pressure changes. Examples include syncope triggered by coughing, swallowing, or straining during urination or a bowel movement.
Medical Evaluation and Next Steps
Any syncope episode, especially one involving incontinence, warrants a medical evaluation to rule out serious underlying conditions. The initial step involves taking a thorough history, including a detailed account of the event from the patient and any witnesses. Key details include the duration of unconsciousness, symptoms experienced immediately before the event, and the person’s state upon waking.
Diagnostic testing often begins with an Electrocardiogram (EKG) to check the heart’s electrical rhythm, as cardiac issues are a serious cause of fainting. Other tests may include checking orthostatic vital signs (measuring blood pressure and heart rate while lying down and standing) and a tilt-table test to evaluate the body’s response to gravity.
Management of Recurrent Vasovagal Syncope
For those diagnosed with recurrent vasovagal syncope, management focuses on avoiding known triggers and using preventative strategies. Simple lifestyle modifications, such as maintaining adequate hydration and increasing salt intake, can help stabilize blood pressure. Patients can also be taught counter-pressure maneuvers to perform at the first sign of lightheadedness, such as crossing the legs or clenching the hands, which temporarily increases blood pressure and prevents fainting.