Cardiorespiratory function measurement

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This page briefly summarises cardiorespiratory function measurements that are used in clinical work and environmental health studies.

PEF
Peak expiratory flow. The largest flow of air that a person is able to produce momentarily during exhale. PEF is typically decreased during an asthma attack. Normal values depend on age, size and other characteristics but are typically 400-600 l/min in adults.
FEV1
Forced expiratory flow during the first second of exhale. Measured with vitalography.
FVC
Forced vital capacity. The largest volume difference in lungs a person can produce between an inhale and an exhale.
Impulse oscillometry (IOS)
IOS apparatus produces small 5 or 20 Hz square oscillations that are applied at the mouth. It measures the impedance (which is the imaginary sum of resistance and reactance) of the respiratory system. It can be used to measure airway hyper-reactivity and obstruction e.g. during provocation test or at rest.
Pulse wave velocity
Measures the speed of a cardiac pulse wave in arteries. It is measured from the time difference of the pulse between carotic and femoral arteries. If the artery wall is stiff, the velocity increases.
Systolic blood pressure
Blood pressure in arteries during a heartbeat. It is the higher value of the two blood pressure values, and it clearly increases during exercise.
Diastolic blood pressure
Blood pressure in arteries just before a heartbeat. It is the lower value of the two, and its long-term increase indicates hypertensive disease.
Augmentation index
The enhancement of the central aortic pressure by a reflected pulse wave. It measures of arterial stiffness.

These variables were used in e.g. Respiratory and cardiovascular responses to walking down a traffic-polluted road compared with walking in a traffic-free area in participants aged 60 years and older with chronic lung or heart disease and age-matched healthy controls: a randomised, crossover study. Rudy Sinharay, MBBS† , Jicheng Gong, PhD† , Benjamin Barratt, PhD , Pamela Ohman-Strickland, PhD , Sabine Ernst, MD , Prof Frank Kelly, PhD , Prof Junfeng (Jim) Zhang, PhD , Prof Peter Collins, MD , Prof Paul Cullinan, MD , Prof Kian Fan Chung, DSc'Correspondence information about the author Prof Kian Fan ChungEmail the author Prof Kian Fan Chung The Lancet. Published: 05 December 2017 Open Access PlumX Metrics DOI: http://dx.doi.org/10.1016/S0140-6736(17)32643-0

More discussion on the topic: CNN (5.12.2017): Working out on polluted streets bears minimal benefit for older people [1]