Dehydration and heatstroke

Dehydration: critical loss of body water.

• Causes: hot flight decks/lines, wind, humidity, diuretic drinks (coffee, tea, alcohol, caffeinated soda).
• Signs: headache, fatigue, cramps, sleepiness, dizziness.
• Thirst is a late warning. A small mouthful can switch it off before loss is replaced.
• Long flight: carry ample water, drink frequently, whether thirsty or not (PHAK ch.17).

Heatstroke: body loses ability to control its temperature.

• Onset may show as ordinary dehydration signs.
• May go unrecognized until sudden collapse.

Trap: headache and cramps are dehydration signs, not motion-sickness signs.

Practice