RESPONSE OF CEREBROSPINAL-FLUID PRESSURE TO CONTINUOUS POSITIVE AIRWAY PRESSURE IN VOLUNTEERS

The effect of a 10-min period of continuous positive airway pressure ( CPAP) of 12 cm H2O on lumbar cerebrospinal fluid pressure (CSFP), cere bral perfusion pressure (CPP), central venous pressure (CVP), mean art erial pressure (MAP), heart rate (HR), and end-tidal carbon dioxide (E Tco(2)) was studied in eight volunteers. CSFP increased (7 +/- 4 contr ol vs 11 +/- 4 mm Hg; P < 0.001; mean +/- SD) and CVP increased (2 +/- 2 control vs 5 +/- 3 mm Hg; P < 0.001; mean +/- SD) when CPAP of 12 c m H2O was applied. CPP decreased slightly during CPAP (79 +/- 13 vs 74 +/- 19 mm Hg; P < 0.05; mean +/- SD), whereas MAP, HR, and ETco(2) re mained unchanged. The findings of our study suggest that changes in CS FP and CPP due to moderate levels of CPAP, although statistically sign ificant, are probably of only minor clinical importance.