Blackouts Due To Multiple Causes

Sometimes syncope is caused by a number of factors occurring at the same time. Each of the factors alone would not result in enough of a fall in blood pressure to cause the person to blackout however together they do.

Example 1: An 85y old lady collapsed when she stood up after lunch in a restaurant.
 

• She had just enjoyed a long, 3 course meal with a couple of glasses of wine.
• The restaurant was crowded and very warm.
• She hadn't drunk much water in the morning in case she needed the toilet whilst travelling on the bus to the restaurant.
• Also, her doctor had increased her blood pressure medication, the week before.

In this example, the factors contributing to her collapse included:

• dehydration,
• low blood pressure after a meal (postprandial hypotension),
• blood vessel dilation from the wine,
• standing up after sitting still for a while (postural hypotension)
• a warm environment and
• a lower background blood pressure due to the higher dose of blood pressure medication.

Example 2: A 23 man collapsed in the shower one morning.

• He had been out with his friends for a few beers the night before.
• He was woken by his neighbour banging on the front door, as they had arranged to go for a training run.
• He got dressed quickly and went for the run, without any breakfast.

In this example, the factors contributing to the young man's collapse included:

• dehydration due to the alcohol the night before,
• no water in the morning
• sweating from the run creating further dehydration
• blood vessel dilation from the run and the hot shower.