Accuracy of calculated arterial saturation in oxygen in neonatal foals and effects of monitor, sensor, site of sensor placement, and degree of hypoxemia on the accuracy of pulse oximetry. (11th September 2014)

• Record Type: Journal Article
• Authors: Giguère, Steeve; Sanchez, L. Chris; Shih, Andre
• Is Part Of: Journal of veterinary emergency and critical care. Volume 24:Number 5(2014:Sep./Oct.)
• Page Start: 529
• Page End: 535
• Publication Date: 2014-09-11
• Subjects: Veterinary emergencies -- Periodicals; Veterinary critical care -- Periodicals; 636.089
• DOI: 10.1111/vec.12231
• Languages: English
• ISSNs: 1479-3261

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <sec id="vec12231-sec-0010" sec-type="section"> <title>Objectives</title> <p>To (1) assess the agreement between calculated values for arterial hemoglobin saturation of oxygen (SaO<sub>2</sub>) and values obtained by co‐oximetry, (2) assess the accuracy of 2 pulse oximetry monitors for measurement of SaO<sub>2</sub> in foals, and for each monitor, and (3) determine the optimal combination of sensor type and site of sensor placement for SaO<sub>2</sub> monitoring.</p> </sec> <sec id="vec12231-sec-0020" sec-type="section"> <title>Design</title> <p>Prospective experimental study.</p> </sec> <sec id="vec12231-sec-0030" sec-type="section"> <title>Setting</title> <p>University teaching hospital.</p> </sec> <sec id="vec12231-sec-0040" sec-type="section"> <title>Animals</title> <p>Six neonatal foals.</p> </sec> <sec id="vec12231-sec-0050" sec-type="section"> <title>Interventions</title> <p>Foals were anesthetized with isoflurane and SaO<sub>2</sub> was manipulated by varying the inspired fraction of oxygen. SaO<sub>2</sub> was calculated from oxygen tension or measured by pulse oximetry using 2 monitors equipped with transmission or reflectance sensors attached to the foal's tongue, lip, ear, or inserted rectally (reflectance sensor only). SaO<sub>2</sub> values measured by co‐oximetry were used as the gold standard to calculate bias.</p> </sec> <sec id="vec12231-sec-0060" sec-type="section"> <title>Measurements and Main Results</title> <p>Mean (±SD) SaO<sub>2</sub> determined by co‐oximetry was 65.2% ± 11.8%, 85.4% ± 2.5%, and 97.2% ± 0.4% at the low, intermediate, and high SaO<sub>2</sub> level, respectively. Sensors attached to the ear failed to provide SaO<sub>2</sub> readings for most attempts. Reflectance sensors placed on the lip or rectally gave significantly larger biases at low SaO<sub>2</sub> (−17.0% and −23.6%, respectively) than at higher levels. Bias of all other combinations of monitors, sensors, and sites (−1.8 to −4.1%) was not significantly influenced by the level of SaO<sub>2</sub> or different from each other. The bias of calculated saturation was similar to that of pulse oximetry.</p> </sec> <sec id="vec12231-sec-0070" sec-type="section"> <title>Conclusions</title> <p>Transmission sensors placed on the lip or tongue or reflectance sensors placed on the tongue give the most accurate assessment of SaO<sub>2</sub> in anesthetized neonatal foals. Calculated saturation is not more accurate than pulse oximetry to estimate SaO<sub>2</sub>.</p> </sec> </abstract>