=Faints, “whitey”.  Insufficient blood to the brain, due to immature or hyporesponsive autonomic nervous system control of cardiac output and peripheral vascular tone.

Similar symptoms with POTS but with obvious drop in blood pressure.

Symptoms of light headedness, feeling hot/clammy, dizziness, black spots in vision or tunnel vision (pre-syncopal), potentially followed by collapse, which can be remembered in most cases. Can be brief posturing or clonus due to hypoxia, but only for a few seconds, which freaks everyone out as it looks like an epileptic seizure.

Recovery is fast, within seconds or a minute, once circulation to brain improves – requires that person is left lying on ground and not propped up!

They look pale, feel hot, but once on ground go clammy/sweaty. Heart rate and blood pressure typically low.

Typically fast growing teenagers, but can be anyone.  In some, lifelong tendency.  You can suffer significant facial trauma from syncope so it’s not trivial, if recurrent can also be disabling with significant psychological co-morbidity. Usually prolonged standing, or standing up after sitting/lying for a while (especially boys going to the toilet for a pee).  Other common triggers are physical stimuli (reflex syncope) eg painful procedures, esp immunisation (distinguish from anaphylaxis), cannulation.  Some unusual triggers eg hair brushing/combing.

Mostly trivial but potential for injury (eg facial fractures) and can be disabling.

Useful to become aware of triggers, so countermeasures can be tried.  But sometimes no warning, which is difficult.  Worth asking directly how often symptoms happen, as child might not tell anyone.

Other differentials are epilepsy, arrhythmia. Syncope with exercise is a red flag.

Abortive manoeuvres

• Lower body muscle tensing – abdomen, buttocks, thighs
• Same, but with leg crossing
• Whole body tensing!
• Squatting
• “Brace” position – sit with head between knees

These should all work, probably worth practicing though.  And should work within seconds.  You hopefully only need to keep doing it for 30-60 seconds. [Krediet, J Appl Physiology 2005 Vol. 99 no. 5, 1697-1703 DOI: 10.1152/japplphysiol.01250.2004]  All of the evidence seems to come from the Netherlands!  Some evidence for isometric arm/hand exercises, but might be incidental abdominal tensing at same time!

Preventive measures

Regular meals/snacks. Avoid big carbohydrate meals though – low GI foods (ie wholegrain/wholemeal) best to avoid big swings in sugar levels. Avoid sugary drinks for the same reason.

Getting hungry is probably bad – have emergency snacks available (oat cakes, nuts, malt loaf, dark chocolate – not high sugar).

Drink plenty – consider increasing to 2-3 litres. Try to drink 1L in the first 2 hours of the day.

Caffeine?

Salt intake may need to be boosted, especially if a “healthy” eater, or losing a lot in sport. Slow salt tablets?

Good cardiovascular fitness.

Could try putting blocks under the foot of the bed to raise it up 2-3 inches! Retrains baroreceptors.

Medication

Desmopressin, to increase circulating blood volume?

Beta blockers? Fludrocortisone? See POTS.

Patient/family info at www.stars.org.uk.