Table 3—

Lung diffusing capacity and its components over five sequential trials in 31 subjects

VariablesPredicted valueTrial 1Trial 2Trial 3Trial 4Trial 5Average of 5 trials
DL,NO mL·min−1·mmHg−1167±18 (137–206)166±29 (115–214)169±29 (114–222)167±31 (112–214)168±30 (110–226)165±30 (108–217)167±29 (112–217)
Dm,CO mL·min−1·mmHg−1#62.4±10.6 (49.1–84.8)**68.8±12.0 (47.3–88.6)69.6±12.1 (47.0–91.9)69.0±12.6 (46.3–88.4)69.3±12.5 (45.4–93.6)68.2±12.4 (44.8–89.8)69.0±12.1 (46.4–89.6)
Dm,CO mL·min−1·mmHg−1¶62.4±10.6 (49.1–84.8)**84.5±14.7 (58.1–108.8)85.5±14.8 (57.8–112.9)84.8±15.5 (56.9–108.6)85.2±15.3 (55.7–114.9)83.8±15.3 (55.0–110.3)84.8±14.9 (57.0–110.0)
DL,CO mL·min−1·mmHg−136.5±4.1 (29–44.5)**32.9±6.0 (23.4–49.6)32.4±5.6 (22.1–43.7)32.1±6.2 (21.2–47.6)31.7±5.8 (21.2–44.1)*31.4±5.9 (20.8–41.9)*32.1±5.8 (21.7–45.4)
Vc mL+75±8 (63–97)**91±16 (59–149)87±13 (56–120)87±16 (59–143)*84±12 (57–116)*83±13 (50–109)*86±13 (58–127)
Vc mL§75±8 (63–97)77±12 (51–120)75±10 (49–100)74±12 (51–115)*73±10 (50–98)*72±10 (52–92)*74±11 (50–105)
  • Data are presented as mean±sd (range). DL,NO: lung diffusing capacity for nitric oxide; Dm,CO: alveolar membrane diffusing capacity for carbon monoxide; DL,CO: lung diffusing capacity for carbon monoxide; Vc: pulmonary capillary blood volume. #: when Dm,CO = DL,NO/2.42; : when Dm,CO = DL,NO/1.97; +: when Dm,CO = DL,NO/2.42; §: when Dm,CO = DL,NO/1.97. *: significantly different from trial one (p<0.05); **: predicted value significantly different from the measured value averaged over five trials (p<0.05). Predicted Dm,CO values are from Zanen et al. 25 and are reported as mL·min−1·mmHg−1. For males, Dm,CO = 3×1/(0.127+0.0003304×age–0.04753×height in m); for females, Dm,CO = 3×1/(0.111+0.0003304×age–0.04753× height in m). Predicted DL,CO = 0.41×height in cm−0.21×age−26.31 (r2 = 0.60; see = 4.8) from Crapo and Morris 32. Vc values are from Zanen et al. 25. For males Vc = 1/(0.04455−0.01805×height in m); for females Vc = 1/(0.04375−0.01805×height in m). Predicted DL,NO in mL·min−1·mmHg−1 = 2.0164×height in cm−175.63 (r2 = 0.39; see = 23.3) from the current study. The units reported are traditional (mL·min−1·mmHg−1). For SI units (mmol·min−1·kPa−1), divide by 3.