[Circadian rhythms op ventilatory mechanical factors in healthy children]

Circadian rhythms in lung resistance (R1) and dynamic compliance (C1dyn) of 7 healthy children (6 to 10 years) were validated (p less than .05) and then quantified (cosinor method); subjects' synchronization: light on at 0700; light off at 2100. Measurements were performed at fixed per hours (0730, 1130, 1630 and 2230) before and after the inhalation of a beta sympathomimetic bronchodilatator: minus 2mg orciprenaline. The measurements carried out after orciprenaline inhalation show a flattening of the curves, both circadian rhythms in R1 and C1 dyn are not detected (p greater than .05).