Physiological Threats Dehydration

How do you build situational awareness? Aviate Navigate Communicate 4. Physiate Noise Hypoxia Stress Spatial D Airsickness Situational Awareness G-LOC Nutrition Fatigue Bad ALSS Barotraumas Hydration

Conflict with co-worker Physiological threats can compound creating a serious safety of flight issue. Circadian disruption Avoidable? Pre-flight temp = 100º Avoidable? High OPTEMPO Avoidable? Conflict with co-worker Avoidable? Haven’t eaten for 8 hrs Avoidable? MANAGEABLE?

Dehydration Can Happen in Cold and Hot Weather

Dehydration can negatively affect mental and physical performance. Increase reaction time Narrowed attention Task fixation 30% reduction in +Gz tolerance Decreased situational awareness

How do I recognize that I am dehydrated? 2-3% body wt loss (24hr) Thirst Elevated heart rate Light headed upon standing Headache Dark urine Dry mouth Nausea General fatigue Reduced SA? Dehydration definitely affects physical performance. A 3% body weight loss due to dehydration can cause a reduction in cardiovascular endurance, a reduction in muscular endurance, reductions in muscular strength and a reduction in muscular power. The impact is greater with increased levels of dehydration. Dehydration can also cause a 30% reduction in Gz tolerance. Even small amounts of dehydration put you at a greater risk of a heat injury. A good rule of thumb for hydration prior to physical activity is to drink until you urinate clear before starting. This is especially true prior to exercise in the heat. Thirst is generally a good indicator of hydration status, unless you are exercising vigorously or are exposed to a challenging thermal environment. In a hot environment you must drink proactively because under these conditions thirst lags behind hydration status. Because dehydration can affect your Gz tolerance and performance, you should treat a flight like an exercise session and ensure that you are well hydrated prior to flight. You should also consider options for in flight hydration. What are your options for in flight hydration? What can you carry? After a particularly challenging flight, you should rehydrate quickly, just as you would after a hard workout. Sports drinks are a good choice. So is water. If all you have is Coke, it is better than nothing. It is not true that you lose more water than you gain when you drink soft drinks. You can hydrate effectively with most water based beverages. Those with high sugar content will take longer to process and caffeinated beverages will result in a small amount of water. Neither issue is particularly significant and shouldn’t prevent you from drinking these beverages to rehydrate if they are all you have access to.

Don’t avoid caffeinated or sugar based drinks without replacing them with other fluids. You can hydrate effectively with most water based beverages high sugar content caffeinated beverages Eating is hydrating 30% of your daily hydration comes from food High fat and high sodium food can dehydrate

What are some dehydration countermeasures? Drink fluids before you are thirsty Drink fluids before and after exercise Drink fluids until your urine is clear Eat food high in water content Avoid high fat and high sodium food Avoid alcohol Dehydration definitely affects physical performance. A 3% body weight loss due to dehydration can cause a reduction in cardiovascular endurance, a reduction in muscular endurance, reductions in muscular strength and a reduction in muscular power. The impact is greater with increased levels of dehydration. Dehydration can also cause a 30% reduction in Gz tolerance. Even small amounts of dehydration put you at a greater risk of a heat injury. A good rule of thumb for hydration prior to physical activity is to drink until you urinate clear before starting. This is especially true prior to exercise in the heat. Thirst is generally a good indicator of hydration status, unless you are exercising vigorously or are exposed to a challenging thermal environment. In a hot environment you must drink proactively because under these conditions thirst lags behind hydration status. Because dehydration can affect your Gz tolerance and performance, you should treat a flight like an exercise session and ensure that you are well hydrated prior to flight. You should also consider options for in flight hydration. What are your options for in flight hydration? What can you carry? After a particularly challenging flight, you should rehydrate quickly, just as you would after a hard workout. Sports drinks are a good choice. So is water. If all you have is Coke, it is better than nothing. It is not true that you lose more water than you gain when you drink soft drinks. You can hydrate effectively with most water based beverages. Those with high sugar content will take longer to process and caffeinated beverages will result in a small amount of water. Neither issue is particularly significant and shouldn’t prevent you from drinking these beverages to rehydrate if they are all you have access to.

Your Aeromedical Safety Officer Located at Wing Safety Office Aviation Life Support Systems Ejection seat briefs PHYSEP and HAZREP submission Custom hearing protection Airsickness desensitization Physiological threat briefs Egress Command Fitness Leader

LT Tim Welsh Wing Safety Office x3997