Table 2.

Hemodynamic and cerebrovascular responses during squat-stand maneuvers

	No Intervention	Indomethacin	Hypocapnia
Baseline, sitting
Mean BP, mmHg	84.1 ± 11.6	85.4 ± 13.5	81.3 ± 9.2
Mean MCAv, cm/s	67.7 ± 10.6	45.5 ± 8.4*	44.7 ± 7.1*
MCA CVRi, mmHg·cm−1·s−1	1.3 ± 0.3	1.9 ± 0.4*	1.9 ± 0.3*
Mean PCAv, cm/s	48.8 ± 10.2	33.6 ± 7.6*	30.5 ± 9.6*
PCA CVRi, mmHg·cm−1·s−1	1.8 ± 0.5	2.6 ± 0.7*	2.9 ± 0.8*
End tidal PCO2, mmHg	41.4 ± 3.6	39.9 ± 3.7	25.5 ± 4.7*†
Breathing frequency, per min	13.8 ± 4.4	14.0 ± 3.8	26.4 ± 6.3*†
Heart rate, bpm	61.2 ± 9.8	52.6 ± 8.3	69.0 ± 12.5†
Squat-stand, 0.05 Hz
Mean BP, mmHg	92.4 ± 13.0	91.4 ± 16.3	89.7 ± 11.9
Mean MCAv, cm/s	59.9 ± 12.9	48.9 ± 9.7*	48.3 ± 7.5*
MCA CVRi, mmHg·cm−1·s−1	1.6 ± 0.4	1.9 ± 0.4*	1.9 ± 0.3*
Mean PCAv, cm/s	45.4 ± 8.2	35.9 ± 8.1*	32.4 ± 7.5*
PCA CVRi, mmHg·cm−1·s−1	2.1 ± 0.4	2.6 ± 0.7*	2.8 ± 0.7*
End tidal PCO2, mmHg	38.9 ± 3.2	37.7 ± 3.5	25.8 ± 4.3*†
Breathing frequency, per min	16.2 ± 4.5	17.5 ± 4.6	27.0 ± 7.0*†
Heart rate, bpm	86.3 ± 14.2	78.7 ± 12.5	84.5 ± 11.2
Squat-stand, 0.10 Hz
Mean BP, mmHg	93.3 ± 15.4	91.2 ± 12.1	89.7 ± 11.1
Mean MCAv, cm/s	60.5 ± 13.8	50.0 ± 9.3*	48.1 ± 7.4*
MCAv CVRi, mmHg·cm−1·s−1	1.6 ± 0.4	1.9 ± 0.3*	1.9 ± 0.3*
Mean PCAv, cm/s	44.9 ± 8.5	36.2 ± 7.0*	33.1 ± 7.5*
PCAv CVRi, mmHg·cm−1·s−1	2.1 ± 0.5	2.6 ± 0.6*	2.7 ± 0.6*
End tidal PCO2, mmHg	39.6 ± 4.4	38.0 ± 4.3	25.5 ± 4.2*†
Breathing frequency, per min	17.0 ± 4.0	18.1 ± 5.0	28.7 ± 7.8*†
Heart rate, bpm	86.0 ± 12.9	79.0 ± 11.6	85.9 ± 11.2

Values are means ± SD.

BP, blood pressure; MCAv, middle cerebral artery velocity; PCAv, posterior cerebral artery velocity; CVRi, cerebrovascular resistance index; bpm, beats per minute.

Statistical significance was set at P < 0.05.

^*Significance from no intervention.

^†Significance from indomethacin intervention.