From the Guidelines
The workup for distinguishing between seizures and syncope should begin with a detailed history and physical examination, followed by targeted diagnostic tests such as an electrocardiogram, electroencephalogram (EEG), and brain imaging, as these tests are essential for identifying the underlying cause of the symptoms and guiding treatment decisions. When evaluating a patient with a history of loss of consciousness, it is crucial to differentiate between seizures and syncope, as the treatment and management of these conditions are distinct.
- A detailed history should include questions about prodromal symptoms, such as lightheadedness, nausea, and visual changes, which may suggest syncope, while auras like strange smells or déjà vu may indicate seizures 1.
- The event itself, including tonic-clonic movements, tongue biting, and incontinence, should be thoroughly described, as these features can help distinguish between seizures and syncope 1.
- Post-event symptoms, such as confusion and sleepiness after seizures versus rapid recovery after syncope, should also be assessed 1. The physical examination should include orthostatic vital signs, cardiac and neurological assessments, as these can provide valuable information about the patient's condition 1. For diagnostic testing, an electrocardiogram is essential for all patients to identify arrhythmias or conduction abnormalities, which can be a cause of syncope 1. Seizure evaluation typically includes an EEG and brain imaging, such as MRI, which is preferred over CT, as it can provide more detailed information about the brain structure and function 1. In contrast, syncope workup may require cardiac monitoring, such as Holter or event monitor, echocardiogram, tilt-table testing, or carotid sinus massage in appropriate patients 1. Laboratory tests, including electrolytes, glucose, and complete blood count, should also be performed to rule out underlying metabolic or hematological disorders that may be contributing to the symptoms 1. The distinction between seizures and syncope is critical, as the treatment and management of these conditions are different, and seizures typically require anticonvulsant medications, such as levetiracetam or lamotrigine, while syncope management addresses the underlying cause, such as volume repletion for vasovagal syncope or pacemaker implantation for cardiogenic syncope 1.
From the Research
Seizure vs Syncope Workup
- The workup for seizures and syncope involves a thorough history and physical examination to determine the underlying cause of the event 2.
- Seizures are a common neurological disorder, affecting 1 in 26 people in the United States, and can be caused by various factors, including neurologic or medical conditions 3.
- The evaluation of a patient presenting with a seizure involves excluding underlying neurologic or medical conditions, classifying the seizure type, and determining if the patient has epilepsy 3.
- Laboratory tests, such as prolactin and creatine kinase levels, can help differentiate between epileptic and non-epileptic seizures, and identify potential causes of symptomatic seizures 4.
- A first seizure presentation in adults requires careful assessment and management, including early specialist assessment and consideration of potential underlying causes, such as metabolic derangements or structural brain lesions 5.
- The use of evidence-based care, including early initiation of antiepileptic drugs, can reduce the risk of early seizure recurrence, but the prognosis for the development of epilepsy is not altered by early intervention 6.
- Key points in the history and physical examination of a patient presenting with a first seizure include:
- Characterization of the event
- Exclusion of alternative diagnoses
- Determination of specific acute or remote causes
- Identification of previously unrecognized seizures
- The role of postictal laboratory blood analyses in the diagnosis and prognosis of seizures includes:
- Differentiation between epileptic and non-epileptic seizures
- Identification of potential causes of symptomatic seizures
- Monitoring for rare, threatening complications, such as rhabdomyolysis or acute renal failure 4.