6 The Diving Response Flashcards
1
Q
The Diving Response
A
- Physiological responses to immersion that overrides the basic homeostatic reflexes
- Optimizes respiration by distributing oxygen stores to the heart and brain, enabling submersion for an extended time:
- Apnoea
- Bradycardia
- Selective vasoconstriction
- Oxygen conservation
2
Q
Diving response stimuli
A
Apnoea:
- arterial chemoreceptors
Face immersion:
- trigeminal nerve endings
3
Q
Factors affecting diving response:
A
- Water temperature
- Lung volume
- Breath-hold time
- Stress
4
Q
Cold protection
A
-Cerebral metabolism decreases with brain cooling
-Brain neural activity abolished at 22°C
To survive submersion:
– normal Tbrain must rescue in 5-7 min
– Tbrain at 30°C must rescue in 10-14 min
5
Q
Diving vs Cold shock response factors:
A
Diving- Fit, cold adapted, dry suit
Shock- Unfit, unhabituated, naked.
6
Q
Control of the diving response
A
Apnoea Trigeminal nerve Carotid chemoreceptors Pulmonary stretch receptors Baroreceptors
