High Altitude, Diving and Space Physiology

Question 1

At what estimated height will a person begin to experience drowsiness, lassitude, mental and muscle fatigue, sometimes headache, occasionally nausea and euphoria?

Answer 1

12,000 ft or 3659 meters

Question 2

At what estimated height will a person begin to experience twitchings and seizures?

Answer 2

18,000 ft or 5486.4 m

Question 3

At what estimated height will a person fall into coma or death due to hypoxia?

Answer 3

23,000ft or 7010.4 m

Question 4

Reflex that will compensate for hypotension during the effects of +G in circulatory system

Answer 4

Baroreceptor reflex

Question 5

Acceleration greater than ___ G causes blackout of vision within a few seconds and unconsciousness shortly after

Answer 5

4-6 G

Question 6

Degree of positive acceleration that the average person can withstand in the sitting position before vertebral fracture is about ___ G

Answer 6

20 G

Question 7

Between positive and negative G, which is less dramatic but is more damaging in the long term

Answer 7

Negative G

Question 8

Between positive and negative G, which causes red out?

Answer 8

Negative G
Eyes are not protected by the cranium, intense hyperemia occurs during strong negative G resulting to eyes becoming temporarily blinded called redout

Question 9

Cerebral edema may happen probably around __ G

Answer 9

-20G

Question 10

To help prevent some of the pooling of blood in the large vessels of the abdomen and delay onset of blackout, aviators tightens which muscles?

Answer 10

Abdominal muscles

Question 11

T/F:

Centrifugal acceleration is of little importance except when the spacecraft goes into abnormal gyrations

Answer 11

True

Question 12

The volume to which a given quantity of gas is compressed is inversely proportional to the pressure is known as _____ law, which is appreciable in the effects of sea depth

Answer 12

Boyle’s law

Question 13

With NITROGEN NARCOSIS, strength wanes at the depth of:

Answer 13

200-250ft

Question 14

With NITROGEN NARCOSIS, drowsiness occurs at depth of:

Answer 14

150-200ft

Question 15

With NITROGEN NARCOSIS, mild narcosis occurs at the depth of:

Answer 15

120ft

Question 16

With the use of hyperbaric oxygen therapy, Clostridial organisms, that grow best in anaerobic conditions, stop growing at O2 pressures greater than _________

Answer 16

70mmHg

Question 17

Conditions that may be addressed by Hyperbaric O2 therapy:

Answer 17

decompression sickness, arterial gas embolism, carbon monoxide poisoning, osteomyelitis, and myocardial infarction.

Question 18

In hyperbaric therapy, O2 is usually administered at PO2 values of _____ atm through a mask or intratracheal tube, whereas the gas around the body is normal air compressed to the same high-pressure level.

Answer 18

2 to 3 atmosphere pressure

Question 19

Major problem of escape from submarines is prevention of _____

Answer 19

air embolism