Tussive syncope is the loss of consciousness following prolonged episodes of vigorous coughing. Patients recover spontaneously a few seconds to minutes later. This condition is associated with overweight middle-aged males with a history of smoking and chronic obstructive lung disease. The diagnosis is based on a detailed history, physical exam, and the appropriate studies.
Tussive syncope, a well-recognized condition, is characterized by a brief loss of consciousness following vigorous coughing  . This syndrome is typically observed in middle-aged men who are overweight smokers with underlying chronic obstructive lung disease (COPD)  . Tussive syncope can also occur in children with asthma as well  . The exact mechanism of tussive syncope is not fully elucidated  . It is important to note, however, that since tussive syncope and adult tussive cough are common  , it is likely that pertussis is underdiagnosed in this age group   . Moreover, tussive syncope may also be associated with underlying diseases of respiratory, cardiovascular, and central nervous systems .
Patients with tussive syncope experience intense and prolonged episodes of coughing prior to losing consciousness, The syncope is rapid, lasts for a very short duration, and resolves spontaneously and completely  . In addition to a paroxysmal cough, other features may include cyanosis and signs related to congestion of the face . Furthermore, the syncope may be accompanied by movement disorders without postictal confusion and loss of bladder or bowel control   . Also, visual disturbance and lightheadedness may precede the syncopal episode  . Antitussive medications and management of chronic obstructive lung disease will cause the decrease of syncope episodes  .
Vital signs may be normal . Notable findings may include wheezing .
Any patient with syncope needs a full workup consisting of the personal medical history, full physical exam, and the appropriate studies. Specifically, details surrounding the onset of the syncope and the overall clinical picture are necessary to differentiate tussive syncope from similar presentations such as seizures and other causes of syncope .
The initial workup should include the complete blood count (CBC), which is typically normal. Additionally, biochemical tests are important to rule out hypoglycemia or other metabolic abnormalities. Very importantly, cultures of the blood, sputum, and throat are usually negative for the typical offending organisms .
With regards to diagnosing pertussis, polymerase chain reaction (PCR) analysis of nasopharyngeal samples can detect Bordetella pertussis  . Furthermore, serologic tests constitute a sensitive method for the identification of pertussis in adult patients . Pertussis has been discovered in patients with prolonged coughing which highlights the notion that adult cases of pertussis are probably not diagnosed or reported adequately .
Chest radiography, which is likely to be normal, should be performed in these patients . Moreover, syncope associated with a cough requires assessment with pulmonary function tests (PFTs) to determine the presence of lung disease .
During further evaluation of syncope, the workup should include an electrocardiogram (ECG), echocardiogram, and a 24 hour ECG monitoring, which are all unremarkable  .
Neurologic workup includes computed tomography (CT) scan of the head and electroencephalography (EEG), which will exclude seizures or some other central nervous system (CNS) causes  .