Accuracy of Pulse Oximetry in Children

Abstract

WHAT'S KNOWN ON THIS SUBJECT: Saturations from pulse oximetry (SpO 2 ) may overestimate arterial oxygen saturations measured by CO-oximetry (SaO 2 ). The overestimation can be affected by location of measurement, perfusion, and skin color. Previous studies are limited by small numbers of observations in a hypoxemic range. WHAT THIS STUDY ADDS:This large sample of hypoxemic patients identified that SpO 2 typically overestimates SaO 2 . Bias and precision varied throughout the SpO 2 range. The SpO 2 range of 81% to 85% had the greatest bias: median SpO 2 6% higher than SaO 2 measured by CO-oximetry. abstract OBJECTIVE: For children with cyanotic congenital heart disease or acute hypoxemic respiratory failure, providers frequently make decisions based on pulse oximetry, in the absence of an arterial blood gas. The study objective was to measure the accuracy of pulse oximetry in the saturations from pulse oximetry (SpO 2 ) range of 65% to 97%. METHODS:This institutional review board-approved prospective, multicenter observational study in 5 PICUs included 225 mechanically ventilated children with an arterial catheter. With each arterial blood gas sample, SpO 2 from pulse oximetry and arterial oxygen saturations from CO-oximetry (SaO 2 ) were simultaneously obtained if the SpO 2 was #97%. RESULTS:The lowest SpO 2 obtained in the study was 65%. In the range of SpO 2 65% to 97%, 1980 simultaneous values for SpO 2 and SaO 2 were obtained. The bias (SpO 2 -SaO 2 ) varied through the range of SpO 2 values. The bias was greatest in the SpO 2 range 81% to 85% (336 samples, median 6%, mean 6.6%, accuracy root mean squared 9.1%). SpO 2 measurements were close to SaO 2 in the SpO 2 range 91% to 97% (901 samples, median 1%, mean 1.5%, accuracy root mean squared 4.2%).CONCLUSIONS: Previous studies on pulse oximeter accuracy in children present a single number for bias. This study identified that the accuracy of pulse oximetry varies significantly as a function of the SpO 2 range. Saturations measured by pulse oximetry on average overestimate SaO 2 from CO-oximetry in the SpO 2 range of 76% to 90%. Better pulse oximetry algorithms are needed for accurate assessment of children with saturations in the hypoxemic range. KEY WORDS oximetry, hypoxia, heart defects, congenital heart disease/ defects, pediatric, mechanical ventilation ABBREVIATIONS ABG-arterial blood gas ABG/SpO 2 pairs-simultaneous measurement of ABG and SpO 2 AHRF-acute hypoxemic respiratory failure A rms -accuracy root mean squared CCHD-cyanotic congenital heart disease FDA-US Food and Drug Administration SaO 2 -arterial oxygen saturations from CO-oximetry SpO 2 -saturations from pulse oximetry

Clinical Practice Guideline: The Diagnosis, Management, and Prevention of Bronchiolitis

“…Accuracy of pulse oximetry is poor, especially in the 76% to 90% range. 110 Further, it has been well demonstrated that oxygen saturation has much less impact on respiratory drive than carbon dioxide concentrations in the blood. 111 There is very poor correlation between respiratory distress and oxygen saturations among infants with lower respiratory tract infections.…”

Algorithms to Estimate PaCO2and pH Using Noninvasive Parameters for Children with Hypoxemic Respiratory Failure

“…For example, pulse oximetry in a low range (Ͻ 87%) may have 95% prediction intervals greater than Ϯ 10% against co-oximetry. 20 For example, if the pulse oximeter reading is 85%, then 50% of the time, the actual S aO 2 on co-oximetry would lie between 75 and 83%, but for 95% certainty, the S aO 2 could range from 64 to 89%. Nevertheless, pulse oximetry in a low range is routinely used for clinical decision making for children with cyanotic congenital heart disease.…”

Dosing and efficacy of intranasal dexmedetomidine sedation for pediatric transthoracic echocardiography: a retrospective study

“…16 Oxygen desaturation was defined as a SpO 2 \ 92% for normoxic patients or as C 5% below awake admission values for cyanotic patients. 17,18 Following completion of the echocardiographic exam, patients were evaluated and discharged according to previously published discharge criteria for pentobarbital sedation in our institution.…”