A health care worker involved in vaccination, drug injection or venipuncture needs to be familiar with signs and symptoms associated with a vasovagal reaction or syncopal attack. Early recognition allows for interventions that can reduce injury to the patient.


Vasovagal signs and symptoms:

(1) hypotension

(2) bradycardia

(3) anxiety

(4) pallor

(5) perspiration

(6) trembling

(7) cool and clammy skin

(8) nausea

(9) rapid, irregular and/or shallow breathing


Syncope may occur suddenly within seconds of a needlestick without any warning signs. It usually occurs within the first 5 to 30 minutes after the event, but may occur several hours later.


The syncope is usually of brief duration, but may last up to 2 hours.


Seizures may occur during vasovagal syncope associated with cerebral anoxia. These may take the form of:

(1) tonic clonic seizures

(2) muscle rigidity


Prevention of injury:

(1) Attention of the health care worker to the patient's appearance and reaction before, during and after the needlestick.

(2) Pad any sharp edges in the immediate area.

(3) A person manifesting symptoms should lie down with the legs raised for up to 30 minutes. A person with a more severe reaction should be observed for a longer period.

(4) An asymptomatic person with a history suggesting needle phobia should sit for several minutes after the procedure.

(5) A person with seizure activity should have tongue protection during the episode.


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