TABLE 2.
Blood gas analyses at base line and during hypoxia exposurea.
| Total (n = 49) | Acclimatization (n = 23) | Control (n = 26) | Estimateb with 95% Cl | p-valuec | |
| Ph | |||||
| Pre-testing: baseline | 7.41(7.39−7.43) | 7.41(7.39−7.43) | 7.41(7.39−7.42) | 0.00(−0.02to0.02) | 1 |
| Pre-testing: 30 min | 7.43(7.41−7.45) | 7.43(7.41−7.47) | 7.43(7.42−7.44) | 0.01(−0.01to0.04) | 0.5175 |
| Pre-testing: 360 min | 7.46(7.44−7.48) | 7.45(7.44−7.48) | 7.46(7.45−7.48) | 0.00(−0.03to0.02) | 0.8756 |
| Post-testing: baseline | 7.39(7.38−7.42) | 7.41(7.38−7.44) | 7.39(7.37−7.41) | 0.02(−0.01to0.05) | 0.2108 |
| Post-testing: 30 min | 7.43(7.41−7.46) | 7.45(7.41−7.5) | 7.43(7.41−7.44) | 0.02(−0.01to0.07) | 0.2124 |
| Post-testing: 360 min | 7.46(7.44−7.47) | 7.46(7.44−7.49) | 7.46(7.44−7.47) | 0.01(−0.02to0.04) | 0.5618 |
| Pa02(mmHg) | |||||
| Pre-testing: baseline | 78(73−82) | 76.0(73.8−79.3) | 80(73−84) | −2(−8to3) | 0.4377 |
| Pre-testing: 30 min | 38(34−1) | 35.5(33.8−38.3) | 39(34−2) | −2(−7to2) | 0.2657 |
| Pre-testing: 360 min | 38(35−2) | 36.0(35.0−39.0) | 41(37−3) | –3 (–7 to 1) | 0.1686 |
| Post-testing: baseline | 77(73−82) | 75.5(72.5−78.8) | 78(74−82) | −2(−6to3) | 0.3626 |
| Post-testing: 30 min | 38(37−43) | 41.0(37.3−44.3) | 38(37−41) | 2 (–2 to 7) | 0.2052 |
| Post-testing: 360 min | 38(36−2) | 39.0(36.8−4.0) | 38(35−40) | 2(−2to6) | 0.3860 |
| Sp02 (%) | |||||
| Pre-testing: baseline | 98.0(97.0−98.0) | 98.0(96.5−98.0) | 98.0(97.0−99.0) | –1 (–2 to 1) | 0.2938 |
| Pre-testing: 30 min | 80.8(78.4−84.3) | 80.0(79.0−88.5) | 81.0(78.0−84.0) | 1.4 (–2.6 to 7.2) | 0.5426 |
| Pre-testing: 360 min | 81.4 (79.2 – 87.7) | 81.2(79.3−85.1) | 81.5(76.8−87.7) | 0.6(−5.9to6.1) | 0.9077 |
| Post-testing: baseline | 97.5(97.0−98.0) | 97.0(96.5−97.5) | 98.0(97.0−98.0) | −1(−1to0) | 0.0633 |
| Post-testing: 30 min | 83.2(78.5−87.0) | 86.1(81.5−90.6) | 80.7(78.0−84.8) | 4.1(−0.7to9.6) | 0.1240 |
| Post-testing: 360 min | 83.8(78.7−85.4) | 84.5(79.7−89.3) | 83.3(78.6−84.8) | 1.4(−3.8to7.6) | 0.5623 |
| PaC02(mmHg) | |||||
| Pre-testing: baseline | 37.5(34.8−0.0) | 37.0(35.0−0.5) | 38(34−39) | 1(−3to4) | 0.8161 |
| Pre-testing: 30 min | 35.5(33.0−38.0) | 34.0(32.5−38.0) | 36(34−38) | –1 (–4 to 2) | 0.5211 |
| Pre-testing: 360 min | 32.5(30.8−36.0) | 32.0(32.0−35.5) | 33(30−36) | 0(−3to3) | 0.9303 |
| Post-testing: baseline | 38.0(36.0−1.3) | 37.0(34.5−41.5) | 39(36−41) | −2(−5to2) | 0.5599 |
| Post-testing: 30 min | 34.5(32.0−38.0) | 32.0(29.0−35.5) | 37(33−38) | −4(−8to0) | 0.0515 |
| Post-testing: 360 min | 33.5(29.8−35.5) | 33.0(28.5−34.0) | 34(32−37) | −2(−6to2) | 0.2557 |
| HVR (L/min%) | |||||
| Pre-testing | 0.64(0.36−1.01) | 0.74(0.50−1.03) | 0.44(0.33−0.96) | 0.22(−0.03to0.48) | 0.0987 |
| Post-testing | 0.60(0.31−0.89) | 0.61(0.30−0.87) | 0.59(0.35−0.87) | −0.03(−0.29to0.23) | 0.8194 |
aBinary data are presented as no./total no. (%), continuous data as medians (25th to 75th percentile). bOdds ratios for binary variables and estimated median difference for continuous variables. cAssessed by Fisher’s Exact Test for categorical variables and Wilcoxon Rank Sum Test for continuous variables in intergroup comparison. Cl reflects confidence interval, pH reflects arterial pH, pa02 reflects arterial partial pressure of oxygen taken from the arterialized earlobe, Sp02 reflects peripheral saturation of oxygen, paC02 reflects arterial partial pressure of carbon dioxide taken from the arterialized earlobe, HVR reflects hypoxic ventilatory response.