Professional
Technical
IVT
peak respiratory exchange ratio
Pronunciation: R-E-R
The ratio of carbon dioxide production to oxygen consumption at peak exercise, indicating metabolic effort level.
Full Definition
Peak respiratory exchange ratio (RER) is calculated as VCO2/VO2 at maximum exercise and indicates the extent of metabolic stress achieved during testing. An RER ≥1.10 generally indicates near-maximal effort in cardiac rehabilitation patients, validating the reliability of measured exercise capacity. Values below 1.0 may suggest submaximal effort due to early test termination, medications, or patient motivation, which affects the interpretation of functional capacity measurements.
Usage
Usage note: Always specify 'peak' to distinguish from RER at other exercise intensities.
In Context
- "The patient achieved a peak respiratory exchange ratio of 1.15, confirming maximal effort during the cardiopulmonary exercise test." — Exercise test interpretation
- "A peak respiratory exchange ratio below 1.05 suggests the test may have been terminated prematurely." — Test quality assessment
Also known as
peak RER
respiratory quotient at peak
Contrasted with
resting RER
Don't confuse with
respiratory quotient
ventilatory efficiency