[Breath drive response of COPD patients with hypercapnic respiratory failure and their families].
OBJECTIVE
To investigate the breath drive response of COPD patients and their offspring and to analyze the potential heredity.


METHODS
P(0.1) and ventilatory response to hypoxia (DeltaV(E)/DeltaSaO(2)), P(0.1) response to hypoxia (DeltaP(0.1)/DeltaSaO(2)), P(0.1) response to hypercapnia (DeltaP(0.1)/DeltaP(ET)CO(2)DeltaV(E)/P(ET)CO(2)) and ventilatory response to hypercapnia (DeltaV(E)/P(ET)CO(2)) were measured in 6 COPD patients with type II respiratory failure and in 21 of their normal adult offspring.


RESULTS
(1) P(0.1) was remarkably higher among all of the COPD patients than among their offspring and normal controls. The hypoxia response (DeltaP(0.1)/DeltaSaO(2)) and DeltaP(0.1)/DeltaP(ET)CO(2) were significantly decreased among the COPD patients (P < 0.05). (2) The hypoxia response was low among 10 of the offspring of COPD patients, and was normal among the other 11. (3) The ventilatory response to hypercapnia (DeltaV(E)/DeltaP(ET)CO(2)) was significantly decreased among the COPD patients, and varied greatly among their offspring.


CONCLUSIONS
(1) The depression of respiratory responses to hypoxia and hypercapnia may be the reason of type II respiratory failure. (2) The depression of hypoxia response may be influenced by genetic factors.
Ji
R
R
Department of Respirology, Second Hospital of Peking University, Beijing 100044, China.
He
Q
Q
Zhang
R
R
D000328:Adult; D000368:Aged; D001784:Blood Gas Analysis; D002245:Carbon Dioxide / Q000494:pharmacology; D005260:Female; D006801:Humans; D006935:Hypercapnia / Q000503:physiopathology*; D000860:Hypoxia / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000235:genetics* / Q000503:physiopathology; D012119:Respiration / Q000187:drug effects
D002245:Carbon Dioxide