pk 8 - Respiratory Rhythmogenesis

Question 1

Breathing requires ………… ………. to coordinate respiratory muscle movement

Answer 1

neural control

Question 2

Whilst …………. control of breathing can be temporarily override by …………… control, it dominates to regulate …….. in the face of changes in VCO2

Answer 2

automatic
conscious
PACO2

Question 3

What are the 2 extremes of respiratory control?

Answer 3

Locked in syndrome - no concious control, cannot alter breathing rate
Ondines curse - no automatic control, have to remember to breathe

Question 4

The respiratory drive to breathe can be modulated by ……… from ……….. and …….. receptors located in the …….. that provide ……….. information

Answer 4

afferents
mechanical 
chemical 
periphery
feedback

Question 5

Describe the 3 phases of neural rhythm, in terms of the diaphragm and accessory muscles

Answer 5

I = inspiratory phase, diaphragm contracts 
PI = post-inspiratory phase, diaphragm slowly relaxes
E-2 = diaphragm is silent but active accessory muscles are contracting

Question 6

The primary respiratory oscillator may be in the ……………. ……………

Answer 6

pre-Botzinger complex

Question 7

Diaphragmatic contraction is driven by the …… and the accessory muscles of respiration are driven by the …… . The …… and higher centres modulate outputs of the …….. and ……..

Answer 7

DRG
VRG
PRG
DRG and VRG

Question 8

1. Which centre influences the timing of breathing?
2. Which centre drives accessory insp/exp?
3. Which pathway bypasses the brainstem nuclei?
4. What does the Botzinger complex do?
5. Which nuclei drives inspiration?

Answer 8

1. PRG
2. VRG
3. voluntary control goes straight from cerebral cortex to spinal cord and muscles of respiration
4. inhibits inspiration, drives expiration
5. DRG

Question 9

What four things can modulate the respiratory rhythm?

Answer 9

Special situations e.g. altitude, exercise
Respiratory stimulants
Sleep
Drugs and respiratory depressors