First aid: Syncope
In the fourth part of our series, Samena Chaudhry and Magnus Harrison explain the management of syncope
Many of us will have fainted or seen someone else faint - in medicine, this is called syncope. Syncope is defined as a transient loss of consciousness associated with a decrease in cerebral blood flow.1 Differentiating true syncope from other “non-syncopal” conditions causing a loss of consciousness is important because the mechanisms of syncope range from nearly normal (physiological) to abnormal and life threatening.
In syncope, bradycardia (a slow heart rate), hypotension, and a weak thready pulse are common. Unconsciousness results in muscular relaxation and may cause the tongue to fall into the oropharynx, obstructing or partially obstructing the airway - this itself is life threatening.2 Although many causes of syncope exist, we will briefly focus on the commonest causes seen in the emergency department.
Presyncope is the period of time when inadequate cerebral circulation and the resulting lack of nutrition and oxygen start to take effect. Early manifestations include