high blood oxygen partial pressure vs breathing rate

[hausee]

does high oxygen partial pressure affect breathing rate?

Campbell 7th edition page 893 says " oxygen concentrations in the blood usually have little effect on the breathing control center. However, when the O2 level is severely depressed................respond by increasing the breathing rate." But should we assume increased blood oxygen partial pressure will decrease breathing rate?

This is one of the destroyer Q. But I think the answer is wrong.

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[UCB05]

does high oxygen partial pressure affect breathing rate?

Campbell 7th edition page 893 says " oxygen concentrations in the blood usually have little effect on the breathing control center. However, when the O2 level is severely depressed................respond by increasing the breathing rate." But should we assume increased blood oxygen partial pressure will decrease breathing rate?

This is one of the destroyer Q. But I think the answer is wrong.

Not in normal people. We respond to high CO2 levels (hypercapneic) and low O2 (hypoxemic) with elevated CO2 drive >> low O2 drive. In people with lung disease (ie COPD), the CO2 levels are chronically elevated so they lose their CO2 drive and their low O2 drive takes over. In these patients, a high O2 level (from supplemental O2) could depress their respiratory drive and they will hold their breath (RR decreases). In a normal person breathing extra O2, when they hold their breath, their O2 (saturation) would be 100% (meaning a PAO2 of >100 mm hg) and they would still need to take a breath once their CO2 starts to rise.