Cerebral blood flow and cerebral oxygen consumption in patients with COPD on mechanical ventilation.
OBJECTIVE
To investigate the effect of PaCO2 on cerebral blood flow (CBF) in chronic obstructive pulmonary disease (COPD).


METHODS
Before-after trial.


METHODS
General ICU in a regional hospital.


METHODS
7 patients undergoing mechanical ventilation because of an exacerbation of COPD.


METHODS
CBF and cerebral metabolic rate of oxygen (CMRO2) of COPD were measured before and after hyperventilation and were compared by those of normal patients. CBF was measured by the Kety-Schmidt technique using 15% N2O.


RESULTS
Hyperventilation produced a significant reduction in CBF in COPD with no concomitant change in CMRO2. CMRO2 in COPD was significantly lower than those in normal patients. The regression equation was shifted significantly more to the right in COPD.


CONCLUSIONS
The sensitivity of CBF in CO2 remained but CMRO2 was reduced markedly in COPD patients.
Sari
A
A
Department of Anesthesia, Kurashiki Central Hospital, Okayama, Japan.
Oshiata
S
S
Toriumi
T
T
Yamashita
S
S
Kojima
S
S
Kakumoto
S
S
Yonei
A
A
D000328:Adult; D000368:Aged; D000403:Airway Resistance; D001783:Blood Flow Velocity; D001784:Blood Gas Analysis; D001921:Brain / Q000378:metabolism*; D002245:Carbon Dioxide / Q000097:blood; D002560:Cerebrovascular Circulation; D005069:Evaluation Studies as Topic; D006439:Hemodynamics; D006801:Humans; D016014:Linear Models; D008173:Lung Diseases, Obstructive / Q000378:metabolism / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009609:Nitrous Oxide; D010101:Oxygen Consumption; D012121:Respiration, Artificial / Q000379:methods / Q000592:standards*; D016896:Treatment Outcome
D002245:Carbon Dioxide; D009609:Nitrous Oxide