The effect of continuous positive airway pressure on cerebral blood flow velocity in awake volunteers.
We measured the effect of 5 and 10 cm H(2)O continuous positive airways pressure (CPAP) on middle cerebral artery blood flow velocity (FV) in 15 awake, healthy volunteers by using transcranial Doppler ultrasonography. Mean, systolic, and diastolic FV plus pulsatility index were recorded. No significant change in any measured variable was observed with the application of 5 or 10 cm H(2)O CPAP. These results are in contrast to those of a previous study, which found a significant increase in mean FV and a decrease in pulsatility index during the application of 12 cm H(2)O CPAP.
Bowie
R A
RA
University Department of Anaesthesia and Intensive Care, City Hospital, Nottingham, UK.
O'Connor
P J
PJ
Hardman
J G
JG
Mahajan
R P
RP
D000328:Adult; D002245:Carbon Dioxide / Q000032:analysis; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D008297:Male; D011175:Positive-Pressure Respiration; D014851:Wakefulness
D002245:Carbon Dioxide