Diagnosis

The history of the nature of attack as well as observation of the episode should establish the diagnosis. Onlookers may describe the person as becoming ‘vacant’ or yawning prior to collapse and this together with typical appearance of pallor and sweating points to the diagnosis of fainting.

Examination may show signs of bradycardia (slow heart rate, weak pulse that is difficult to find and pallor of the hands and feet. The blood pressure will be low (systolic pressure below 100mm Hg). General examination should be undertaken to exclude signs of cardiac murmur or neurological changes.

Episodes of simple vasovagal fainting usually recover spontaneously and require no follow up investigation.

If the period of unconsciousness is prolonged or accompanied by an extended convulsion then investigations such as electrocardiogram (ECG) or electroencephalogram (EEG) are indicated to exclude an underlying cardiac or neurological cause.

If the initial findings suggest a more serious underlying problem then more extensive investigation is needed depending on the possible causes.