Table 2 Inspiratory and expiratory lung and lobe volumes as determined using CT in the supine position with arms raised, standing position with arms down, and sitting position with arms down (100 volunteers).

From: Comparison of inspiratory and expiratory lung and lobe volumes among supine, standing, and sitting positions using conventional and upright CT

  Lung and lobe volumes on CT
Average ± SD (Range)
P value Average percent increase/decrease in volume in standing position compared to that in supine position (%) Average percent increase/decrease in volume in sitting position compared to that in supine position (%) Average percent increase/decrease in volume in sitting position compared to that in standing position (%)
Supine (mL) Standing (mL) Sitting (mL) Supine vs. standing Supine vs. sitting Standing vs. sitting
Total (Bilateral) lung (Inspiratory) 4286.2 ± 1091.7
(2404.5‒7216.3)
4682.6 ± 1055.4
(2726.9‒7481.2)
4713.5 ± 1112.3
(2704.0‒7477.6)
< 0.0001 < 0.0001 0.3134 + 9.2 + 10.0  + 0.7
Right lung (Inspiratory) 2286.4 ± 554.8
(1282.4‒3724.6)
2481.5 ± 540.4
(1550.8‒3956.4)
2508.4 ± 576.2
(1596.7‒3982.9)
< 0.0001 < 0.0001 0.1026 + 8.5 + 9.7  + 1.1
 Right upper lobe (Inspiratory) 786.1 ± 196.9
(383.3‒1289.2)
847.9 ± 198.0
(451.3‒1335.4)
852.8 ± 204.5
(435.4‒1382.4)
< 0.0001 < 0.0001 0.2484 + 7.9 + 8.5 + 0.6
 Right middle lobe (Inspiratory) 383.0 ± 111.6
(189.1‒747.6)
382.5 ± 106.6
(173.7‒670.8)
386.6 ± 112.9
(172.3‒678.8)
0.8896 0.3212 0.1588 − 0.1 + 0.9 + 1.1
 Right lower lobe (Inspiratory) 1117.2 ± 313.4
(547.2‒1905.8)
1251.1 ± 303.9
(637.8‒2218.5)
1269.0 ± 322.7
(646.4‒2108.4)
 < 0.0001  < 0.0001 0.0777 + 12.0 + 13.6 + 1.4
Left lung (Inspiratory) 1999.9 ± 543.8
(1045.5‒3491.8)
2201.1 ± 521.4
(1100.7‒3524.8)
2205.1 ± 542.8
(1084.9‒3494.7)
 < 0.0001  < 0.0001 0.7876 + 10.1 + 10.3 + 0.2
 Left upper lobe (Inspiratory) 1009.3 ± 250.2
(540.9‒1692.9)
1073.9 ± 243.0
(633.9‒1676.2)
1078.3 ± 251.8
(649.2‒1711.9)
< 0.0001 < 0.0001 0.4176 + 6.4 + 6.8 + 0.4
 Left lower lobe (Inspiratory) 990.5 ± 319.6
(382.5‒1798.8)
1127.3 ± 309.6
(418.0‒1905.8)
1126.8 ± 322.2
(413.3‒1913.2)
< 0.0001 < 0.0001 0.9621 + 13.8 + 13.8 − 0.0
Total (Bilateral) lung (Expiratory) 2688.0 ± 683.5
(1442.6‒4541.0)
2859.8 ± 760.0
(1388.4‒4937.8)
2943.6 ± 778.9
(1396.9‒5589.4)
< 0.0001 < 0.0001 0.0347 + 6.4 + 9.5 + 2.9
Right lung (Expiratory) 1460.6 ± 356.4
(806.5‒2477.5)
1538.7 ± 396.4
(742.2‒2712.6)
1588.0 ± 413.0
(764.7‒3025.5)
0.0004 < 0.0001 0.0208 + 5.3 + 8.7 + 3.2
 Right upper lobe (Expiratory) 537.7 ± 151.4
(236.2‒911.2)
603.4 ± 156.1
(299.4‒985.8)
611.8 ± 160.8
(306.3‒1066.9)
< 0.0001 < 0.0001 0.1925 + 12.2 + 13.8 + 1.4
 Right middle lobe (Expiratory) 282.7 ± 80.3
(150.2‒512.7)
236.7 ± 73.5
(83.0‒432.3)
242.7 ± 77.1
(121.8‒497.1)
< 0.0001 < 0.0001 0.1194 − 16.3 − 14.1 + 2.5
 Right lower lobe (Expiratory) 640.2 ± 178.4
(309.9‒1203.6)
698.6 ± 213.7
(287.6‒1294.6)
733.5 ± 216.1
(293.0‒1461.4)
< 0.0001 < 0.0001 0.0036 + 9.1 + 14.6 + 5.0
Left lung (Expiratory) 1227.4 ± 333.9
(636.2‒2063.5)
1321.1 ± 368.6
(571.6‒2275.1)
1355.6 ± 370.6
(616.1‒2564.0)
< 0.0001 < 0.0001 0.0652 + 7.6 + 10.4 + 2.6
 Left upper lobe (Expiratory) 684.6 ± 186.2
(339.7‒1251.4)
724.7 ± 186.7
(359.1‒1237.2)
733.0 ± 191.2
(356.5‒1434.7)
< 0.0001 < 0.0001 0.3584 + 5.9 + 7.1 + 1.1
 Left lower lobe (Expiratory) 542.9 ± 168.1
(223.8‒1050.2)
596.4 ± 202.3
(212.5‒1190.6)
622.6 ± 199.6
(189.9‒1137.2)
< 0.0001 < 0.0001 0.0108 + 9.9 + 14.7 + 4.4
  1. P < 0.0167 was considered to be statistically significant, with Bonferroni correction for multiple comparisons.