Comparison of cerebral oxygen saturation in premature infants by near-infrared spatially resolved spectroscopy: observations on probe-dependent bias

TY - JOUR

T1 - Comparison of cerebral oxygen saturation in premature infants by near-infrared spatially resolved spectroscopy: observations on probe-dependent bias

AU - Sorensen, Line C

AU - Leung, Terence S

AU - Greisen, Gorm

N1 - Keywords: Artifacts; Brain; Computer-Aided Design; Equipment Design; Equipment Failure Analysis; Female; Humans; Infant, Newborn; Infant, Premature; Male; Oximetry; Oxygen; Oxygen Consumption; Reproducibility of Results; Sensitivity and Specificity; Spectroscopy, Near-Infrared; Transducers

PY - 2008

Y1 - 2008

N2 - Spatially resolved spectroscopy (SRS) allows the estimation of absolute tissue oxygen saturation, the ratio of oxygenated to total hemoglobin concentration, which may facilitate the comparison of results among patients. Eighty-two premature infants were included over two years. The cerebral tissue oxygenation index (c-TOI) was measured using NIRO 300 (Hamamatsu Photonics KK). c-TOI was measured at several positions in each infant. c-TOI varied over time, increasing in the first third and decreasing in the last third of the study period (p<10(-6)). Two probes were used in the study, and a highly significant difference was found between these (p<10(-6)). The mean difference was 8.5% (95%CI 5.4 to 11.6%). After correction for this difference, there was no variation over time. A conclusive explanation for the bias could not be identified. Since the study groups were well distributed, the bias had no influence on the results of our clinical study. We investigated an unexpected but highly significant probe-dependent bias in c-TOI with no conclusive explanation. Hence, comparisons of absolute TOI between groups of patients and among studies should be regarded with caution. A better strategy to detect potential instrumental problems will be useful in preventing biased c-TOI from occurring Udgivelsesdato: 2008/11

AB - Spatially resolved spectroscopy (SRS) allows the estimation of absolute tissue oxygen saturation, the ratio of oxygenated to total hemoglobin concentration, which may facilitate the comparison of results among patients. Eighty-two premature infants were included over two years. The cerebral tissue oxygenation index (c-TOI) was measured using NIRO 300 (Hamamatsu Photonics KK). c-TOI was measured at several positions in each infant. c-TOI varied over time, increasing in the first third and decreasing in the last third of the study period (p<10(-6)). Two probes were used in the study, and a highly significant difference was found between these (p<10(-6)). The mean difference was 8.5% (95%CI 5.4 to 11.6%). After correction for this difference, there was no variation over time. A conclusive explanation for the bias could not be identified. Since the study groups were well distributed, the bias had no influence on the results of our clinical study. We investigated an unexpected but highly significant probe-dependent bias in c-TOI with no conclusive explanation. Hence, comparisons of absolute TOI between groups of patients and among studies should be regarded with caution. A better strategy to detect potential instrumental problems will be useful in preventing biased c-TOI from occurring Udgivelsesdato: 2008/11

U2 - 10.1117/1.3013454

DO - 10.1117/1.3013454

M3 - Journal article

C2 - 19123660

SN - 1083-3668

VL - 13

SP - 064013

JO - Journal of Biomedical Optics

JF - Journal of Biomedical Optics

IS - 6

ER -