[Blood gas changes in Duchenne type muscular dystrophy].
We studied changes in blood gas data from 32 patients with Duchenne type muscular dystrophy (DMD), who were followed for more than 5 years. Regression lines for each blood gas variable were obtained by the least square regression method, from 276 observations. The mean change per year was calculated by averaging the individual slopes. All blood gas variables (PaO2, PaCO2, pH, and [HCO3-]) correlated significantly with age the regression lines were: PaO2 = 95.6-0.45x Age, PaCO2 = 34.7 + 0.70x Age, pH = 7.397-0.0023x Age, [HCO3-] = 20.7 + 0.28x Age. The rates of change were -0.74 Torr/year for PaO2, 1.07 Torr/year for PaCO2, -0.0028 per year for pH and 0.55 mEq/l/year for [HCO3-]. The slope of each regression line was within the average individual yearly change +/- one standard deviation. AaDO2 did not change significantly with age, but chronic respiratory acidosis worsened because of alveolar hypoventilation. As an index of the severity of DMD, PaCO2 was better than PaO2, because the former was more strongly correlated with age and the values of PaCO2 deviated less from the the regression line.
Takasugi
T
T
National Higashi-saitama Hospital, Japan.
Ishihara
T
T
Kawamura
J
J
Sasaki
K
K
Toyoda
T
T
Oosumi
M
M
Suzuki
K
K
Nishio
K
K
Aoyagi
T
T
Kawashiro
T
T
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001784:Blood Gas Analysis; D002245:Carbon Dioxide / Q000097:blood*; D002648:Child; D006801:Humans; D008297:Male; D009136:Muscular Dystrophies / Q000097:blood*; D010100:Oxygen / Q000097:blood*; D012044:Regression Analysis
D002245:Carbon Dioxide; D010100:Oxygen