Jp. Kress et al., Determination of hemoglobin saturation in patients with acute sickle chestsyndrome - A comparison of arterial blood cases and pulse oximetry, CHEST, 115(5), 1999, pp. 1316-1320
Citations number
22
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Study objectives: To evaluate three different methods of measuring oxygen s
aturation in patients suffering from acute sickle chest syndrome.
Design: A prospective, descriptive study of 9 months' duration.
Setting: A tertiary care university hospital.
Patients: Adult patients with acute sickle chest syndrome scheduled to unde
rgo RBC exchange transfusion.
Interventions: None.
Measurements: Baseline hemoglobin oxygen saturation was determined simultan
eously by (1) calculation based on PaO2 and an oxyhemoglobin dissociation c
urve algorithm, (2) co-oximetry, and (3) pulse oximetry, These same measure
s were repeated after exchange transfusion. Baseline and postexchange hemog
lobin electrophoresis was performed in all patients.
Results: Baseline calculated saturation overestimated hue saturation (deter
mined by co-oximetry) with a baseline mean bias (co-oximetry minus calculat
ed saturation) of -6.78 +/- 2.63% (95% confidence interval for bias: -8.37%
to -5.19%). Pulse oximetry was not different than co-oximetry at baseline
with a baseline bias of +1.86 +/- 3.25% (95% confidence interval: -0.1% to
3.82%). After exchange transfusion, there was no bias between either co-oxi
metry and calculated saturation (mean difference: -0.17 +/- 1.31% [95% conf
idence interval: -0.95% to 0.61%]), or co-oximetry and pulse oximetry (mean
difference: +0.3 +/- 1.53% [95% confidence interval: -0.62% to 1.22%]).
Conclusions: Calculated saturation overestimates true saturation during acu
te sickle chest syndrome. This discrepancy abates after exchange transfusio
n. Pulse oximetry more closely follows co-oximetry than does calculated sat
uration during acute sickle chest syndrome.