The accuracy of a fiberoptic oximeter over a wide range of arterial oxygen saturation values in piglets.
A piglet model was used to evaluate the accuracy of a fiberoptic oximeter over a wide range of arterial oxygen saturation (SaO2) values. In eight anaesthetized piglets, the inspired oxygen concentration was varied from 30% to 6% resulting in a SaO2 range from 100% to 15%. Paired data of the Opticath fiberoptic catheter, which was placed in the descending aorta, and blood sample SaO2 values assessed by a multiwavelength oximeter, were analysed. After in vitro calibration according to the manufacturer's instruction, the fiberoptic catheter started to underestimate the SaO2 below 78%, worsening towards lower SaO2 values. The overall bias was -3.4% and the precision 3.8%. An off-line fit with a non-linear model resulted in a standard deviation of residuals of 2.6%. After several in vivo calibration adjustments when the fiberoptic oximeter deviated more than 4% from the blood sample value, the bias was eliminated over the total SaO2 range and the precision was 3.7%. The Opticath fiberoptic oximeter could have an accuracy for the whole SaO2 range between 15-100% close to the accuracy of the multiwavelength oximeter, when the fiberoptic oximeter is adapted for the underestimation below 78% SaO2.
Nijland
R
R
Department of Obstetrics & Gynaecology, Faculty of Medical Sciences, University of Nijmegen, The Netherlands.
Jongsma
H W
HW
Nijhuis
J G
JG
Oeseburg
B
B
D000768:Anesthesia, General; D000818:Animals; D001011:Aorta; D015982:Bias; D002138:Calibration; D002404:Catheterization / Q000295:instrumentation; D004195:Disease Models, Animal; D005260:Female; D005336:Fiber Optic Technology / Q000295:instrumentation; D000860:Hypoxia / Q000097:blood; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation* / Q000592:standards; D010092:Oximetry / Q000295:instrumentation* / Q000592:standards; D010100:Oxygen / Q000008:administration & dosage / Q000097:blood*; D012044:Regression Analysis; D013552:Swine
D010100:Oxygen