Diving Response 1

Question 1

• During breath-hold diving in an average individual, the apnea duration is mainly based on the
  body’s tolerance to the increased…

*What can also play a role

• what do breath-hold durations range from

Answer 1

• During breath-hold diving in anaverage individual, the apnea duration is mainly based on the
  body’s tolerance to the increased PaCO2 (arterial carbon dioxide tension)
• Decreased PaO2 (arterial oxygen tension) can also play a role
• Breath-hold durations range from 15-20 seconds and rarely exceed 2-minutes

Question 2

Hydrostatic Pressure
* The deeper you dive….

Water Temperature
* Cooler temperatures ….
* Peripheral ________

Answer 2

• The deeper you dive the more pressure you experience
• Cooler temperatures change metabolism
• Peripheral vasoconstriction

Question 3

Pressure-Volume Relationships - test question, at given volume

• at atmosphere 1 what is depth and lung volume
• at atmosphere 2 what is depth and lung volume
• at atmosphere 3 what is depth and lung volume
• at atmosphere 4 what is depth and lung volume
• at atmosphere 6 what is depth and lung volume
• at atmosphere 6 what is depth and lung volume
• at atmosphere 7 what is depth and lung volume
• at atmosphere 10 what is depth and lung volume

Answer 3

• 0m/0ft and 1/1 (6L)
• 10m/33ft and 1/2 (3L)
• 20m/66ft and 1/3 (2L)
• 30m/99ft and 1/4 (1.5L)
• 40m/133ft and 1/5 (1.2L)
• 50m/166ft and 1/6 (1L)
• 60m/199ft and 1/7 (0.85L)
• 91m/300ft and 1/10 (0.6L)

Question 4

• Boyle’s law (P1V1=P2V2): At constant temperature, the volume of a given mass of gas varies…
• When pressure doubles, volume ______; conversely, reducing pressure by one half expands…
• Failure to permit the extra air volume to escape through the nose or mouth during ascent…
• The diving depth is limited by the understanding of Boyle’s law: there are physical limitations into how we can accumulate or divert blood to…as a result of what

Answer 4

• Boyle’s law: At constant temperature, the volume of a given mass of gas varies inversely with its pressure
• When pressure doubles, volume halves; conversely, reducing pressure by one half expands
  any gas volume to twice its previous size
• ruptures lung tissue from the powerful force of expanding gases (especially important during scuba)
• to the central region, as a result of the chest deformation under hyperbaric conditions

Question 5

Three possible outcomes may occur due to the environment in which there is an excessive pressure on the lung and chest during apnea

1. Alveolar _____ with formation of atelectasis - complete or partial collapse of….
2. Infiltration of _____ from the capillaries into…
3. Disruption of the AC mem with bleeding into…

• These changes in lung function are indicative of….

Answer 5

1. Alveolar collapse with formation of atelectasis - complete or partial collapse of the entire lung (or lobe)
2. Infiltration of liquid from the capillaries into the airways and alveolar space
3. Disruption of the alveolar-capillary membrane with bleeding into the empty spaces

• These changes in lung function are indicative of pulmonary edema

Question 6

• Henry’s law: At constant temperature, the amount of gas absorbed is proportional to the solubility coefficient of the….. and their….
• increase pressure moves….
• decrease pressure moves…
• why does o2 go up in blood the father we go down
• what is shallow water black outs

Answer 6

• Henry’s law: At constant temperature, the amount of gas absorbed is proportional to the solubility coefficient of the particular gas and their partial pressure
• increase pressure moves gas to liquid
• decrease pressure moves gas from liquid
• o2 go up in blood the father we go down because increase pressure means oxygen into blood until at zero
• when we reach near surface we do not have enough resources to combat widening of airways so we plummet and brain doesn’t have nutrients so pass out (lack of o2 brain)

Question 7

• if a scuba diver starts to ascend while holding his breath (or with air otherwise trapped in the lungs), as air…. and can damage
• Expanding air may rupture the ____ and cause a ____
• Arterial gas embolisms occur when nitrogen bubbles are….through alevoli resulting in
• Decompression sickness produces symptoms related to the effects of bubbles on…

Answer 7

• the air expands as the ambient water pressure decreases (like a balloon). This can damage the alveoli
  and bronchial passages
• Expanding air may rupture the lung and cause a pneumothorax
• Arterial gas embolisms occur when nitrogen bubbles are forced into the bloodstream through alveoli resulting in blockages when bubbles reach smaller blood vessels (cerebral arterial gas embolism occurs in brain)
• on areas of body: tissues, spinal cord, brain, lungs, skin, and the inner ear.

Question 8

• The risk of arterial gas embolism development can be decreased by avoidance of what two things
• Risk of decompression sickness is decreased by reduction of exposure or by elimination of what..
• A decompression schedule specifies the stop times typically at…according to the maximum dive depth and bottom time

Answer 8

• The risk of arterial gas embolism development can be decreased by avoidance of breath holding, rapid
  ascent
• decreased exposure or by elimination of inert gas before (higher oxygen concentrations) or during decompression
• A decompression schedule specifies the stop times typically at 3 m intervals during ascent according to the maximum dive depth and bottom time

Question 9

• Deadspeace VE before snorkeling
• Total ventilation, alveolar ventilation before snorkel
• Deadspeace VE with snorkeling
• alveolar ventilation with snorkel

Answer 9

• 2250ml/min (150ml dead space x 15, frequency)
• 7500ml/min is total vetilation and alveolar ventilation is 3000ml/min (dead space ve + va = total)
• 350 ml snorkle + 150 ml spead space = 500x15 = 7500ml/min
• VA is zero because deadspace + snorkle take it all up (no VA means lungs get tired quicker

Question 10

• Increased pulmonary deadspace by…
• Need to increase Tidal Volume otherwise limits access to..
• Hydrostatic pressure on the chest cavity is increased as…
• Compressive force against the chest cavity becomes so large that the inspiratory muscles

Answer 10

• Increased pulmonary deadspace by enlarging the snorkel’s volume
• Need to increase Tidal Volume otherwise limits access to fresh air/encroaches on alveolar VE (match ventilation)
• Hydrostatic pressure on the chest cavity is increased as one descends beneath the water
• cannot overcome the external pressure to breathe deep enough to exchange gases

Question 11

• what does the mammalian reflex override
• seen in all vertebrates (of mammals) as a protective mechanism when we are rendered apneic by…

The dive response mainly consists of four independent reflex behaviors
- an a______
* a parasympathetically mediated _______
* a sympathetically mediated …
* ______ contraction

Answer 11

• overrides basic homeostatic reflexes
• seen in all vertebrates (of mammals) as a protective mechanism when we are rendered apneic by
  underwater submersion
• an apnea
• a parasympathetically mediated bradycardia (less o2 per beat)
• a sympathetically mediated peripheral vasoconstriction (stop using o2 in peripheral to redirect to core)
• splenic contraction (spleen has rbc)

Question 12

Mammalian Dive Response
- This reflex is triggered by the innervation of the _________ nerve

why?
- all 3 zone and what involves them

Answer 12

• This reflex is triggered by the innervation of the trigeminal nerve
• trigeminal nerve involves 3 zones of the face covering eyes nose and mouth and because all of face is innervated it controls sense for air gettting into the body