Canadian Respiratory Journal

Research Article

Daily Chronic Intermittent Hypobaric Hypoxia Does Not Induce Chronic Increase in Pulmonary Arterial Pressure Assessed by Echocardiography

Table 3

Lowland echocardiography and blood gas analysis at rest and during exercise .


	CIHH	Control	value

Echocardiography at rest
LVEDD (mm)	45.50 ± 3.42	43.75 ± 2.82	0.28
LV-EF (%)	67.63 ± 2.39	65.57 ± 2.37	0.11
RVEDD (mm)	35.25 ± 3.20	32.88 ± 2.36	0.11
sPAP, not measurable at rest (n)	3	4
sPAP (mmHg)	20.20 ± 3.27	18.50 ± 2.08	0.39
TAPSE (mm)	23.88 ± 3.48	22.67 ± 2.58	0.48
Vital signs rest lowland
HR (bpm)	78.28 ± 13.64	77.5 ± 11.64	0.91
Mean RR (mmHg)	94.95 ± 10.37	92.83 ± 8.31	0.69
Blood gas analysis rest lowland
pO₂ (mmHg)	86.41 ± 4.55	85.49 ± 5.91	0.73
pCO₂ (mmHg)	33.63 ± 4.63	37.65 ± 3.17	0.06
pH	7.43 ± 0.03	7.43 ± 0.02	1.00
BE (mmol/l)	−0.90 ± 2.21	0.64 ± 1.08	0.09
SaO₂ (%)	97.29 ± 0.43	97.00 ± 0.74	0.37
AaDO₂	21.2 ± 5.5	17.1 ± 6.1	0.18
Exertion 150 W
HR (bpm)	134.42 ± 12.71	142.5 ± 21.35	0.41
Mean RR (mmHg)	120.58 ± 13.66	110.27 ± 19.14	0.26
sPAP (mmHg)	28.75 ± 3.99	35.33 ± 2.89	0.02
TAPSE (mm)	30.00 ± 2.83	31.17 ± 5.23	0.59
SpO₂ (%)	99.33 ± 1.21	94.75 ± 2.60	0.001

CIHH: chronic intermittent hypobaric hypoxia; LVEDD: left ventricular end diastolic diameter; LV-EF: left ventricular ejection fraction; RVEDD: right ventricular end diastolic diameter; sPAP: systolic pulmonary arterial pressure; TAPSE: tricuspid annular plane systolic excursion; pO₂: oxygen partial pressure; pCO₂: carbon dioxide partial pressure; BE: base excess; SaO₂: arterial oxygen saturation; SpO₂: peripheral oxygen saturation;by t-test; due to lack of TI, sPAP was not measurable in all subjects at rest at lowland; mean sPAP is therefore calculated from the remaining subjects only. During exercise and at altitude, sPAP was measurable in all subjects.