musculoskeletal pump

Question 1

what is the respiratory cycle?

Answer 1

1 inspiration

1 expiration

Question 2

which muscles help with inhalation?

Answer 2

external intercostals aid in quiet and forced

Question 3

which muscles help with expiration?

Answer 3

internal intercostals aid in forced

Question 4

what is the zone of apposition?

Answer 4

-angle formed between ribcage and diaphragm where it connects
acute angle=normal
45-90= flattened diaphragm

Question 5

what motion does the sternum make

Answer 5

pump handle

Question 6

what motion does the ribcage make

Answer 6

bucket handle

Question 7

what is abdominal paradox

Answer 7

the inward motion of the abdomen as the rib cage expands during inspiration

• shows diaphragm weakness
• using accessory muscles to breathe
• diaphragm can get sucked up

Question 8

what is the sniff test

Answer 8

to test diaphragm weakness/palsy

-descent of diaphragm will be seen in people without the disorder

Question 9

what is MIP

Answer 9

maximal inspiratory pressure
-lowest pressure developed during forceful inspiration against an occluded airway

primarily measures inspiratory muscle strength

indicates if a ventilator is required

Question 10

what is MEP

Answer 10

maximal expiratory pressure
-highest pressure developed during forceful exhalation against an occluded airway

primarily measures expiratory muscle strength
positive number

its with neurogenic conditions

Question 11

what is MVV

Answer 11

maximal voluntary ventilation

• total volume of air exhaled during 12 sec of rapid, deep breathing
• measures breathing reserve (respiratory muscle endurance)

recorded as l/min

Question 12

which factors influence breathing?

Answer 12

• hypothalamus (emotions, pain)
• cortex (voluntary control)
• chemoreceptors (central and peripheral)

Question 13

what do the central chemoreceptors do

Answer 13

• respond to increase in co2
• in medulla oblongata
• co2 passes blood brain barrier
• h stimulates receptors and leads to increased breathing depth and rate

Question 14

what do the peripheral chemoreceptors do

Answer 14

• respond to low levels of o2 and some co2
• in aortic/carotid bodies
• respond when o2< 60 leading to increased ventilation
• respond to decrease in pH which leads to increased ventilation

Question 15

talk about control of breathing and central chemoreceptors

Answer 15

-sensitive to H in the extra cell fluid
-however, h doesn’t cross BBB but co2 can
-

Question 16

talk about control of breathing and peripheral chemoreceptors

Answer 16

• sensentivie to o2 greater than co2
• pao2 < 60
• synergistic effect w higher paco2
• hypoxic drive

-respond to oxygen but have to drop low before they kick in

Question 17

what is flail chest

Answer 17

• result of multiple rib fractures on the same rib= free floating segments
• causes wasted effort, pain, not much can be done

Question 18

what is respiratory muscle fatigue

Answer 18

supply: energy available (BF, O2)
demand: energy required (WOB, strength, effifeicny)

Question 19

can dyspnea be a psychological event?

Answer 19

yes

Question 20

what happens in patients with chronic COPD and elevated CO2?

Answer 20

-central chemoreceptors become less sensitive to Co2 due to overexposure so the peripheral receptors become more important

Question 21

what makes peripheral chemoreceptors fire?

Answer 21

low O2

high CO2

Question 22

what happens if you give supplemental O2 to increase PaO2?

Answer 22

you will not turn off drive to breathe