Chest
Original ResearchCritical Care MedicineComparison of the Spo2/Fio2 Ratio and the Pao2/Fio2 Ratio in Patients With Acute Lung Injury or ARDS
Section snippets
Derivation Data Set
Corresponding measurements of Spo2 and Pao2 from patients enrolled in the National Heart, Lung, and Blood Institute ARDS Network trial11 comparing tidal volumes of 6 mL/Kg predicted body weight (PBW) with those of 12 mL/kg were utilized to establish the relationship between S/F and P/F ratios. Each ARDS Network site received approval from local institutional review boards to conduct the studies. The inclusion and exclusion criteria for the ARDS Network tidal volume study11 have been reported
Results
Of the 861 patients enrolled in the study comparing tidal volumes of 6 and 12 mL/kg PBW, 189 were enrolled at sites located at > 1,000 m in altitude (Fig 1). The remaining 672 patients provided 3,384 Pao2 and Spo2 measurements at known Fio2 values. Spo2 exceeded 97% in 711 patients, leaving 2,673 data points for analysis in the derivation data set. Of the 549 patients who were enrolled in the trial comparing high and low PEEP, 146 were enrolled at centers that were at altitudes of > 1,000 m,
Discussion
We hypothesized that the continuously available S/F ratio can serve as a surrogate for P/F ratio in the diagnostic criteria for ALI/ARDS. Using data from patients with ALI and ARDS who were enrolled in two large clinical trials,11,14 we found that S/F ratio correlates well with a simultaneously obtained P/F ratio. The correlation improves slightly if PEEP is included in the regression model. S/F ratios of 235 and 315, were found to correspond to P/F ratios of 200 and 300, respectively, which
References (43)
- et al.
Control of blood gas measurements in intensive-care units
Lancet
(1991) - et al.
Meta-analysis of arterial oxygen saturation monitoring by pulse oximetry in adults
Heart Lung
(1998) - et al.
Reliability of pulse oximetry in titrating supplemental oxygen therapy in ventilator-dependent patients
Chest
(1990) - et al.
Variability of arterial blood gas values in stable patients in the ICU
Chest
(1983) - et al.
Variability of arterial blood gas values over time in stable medical ICU patients
Chest
(1994) Advances in respiratory monitoring during mechanical ventilation
Chest
(1999)- et al.
Development of a clinical definition for acute respiratory distress syndrome using the Delphi technique
J Crit Care
(2005) - et al.
The APACHE III prognostic system: risk prediction of hospital mortality for critically ill hospitalized adults
Chest
(1991) - et al.
The acute respiratory distress syndrome
N Engl J Med
(2000) - et al.
Incidence and outcomes of acute lung injury
N Engl J Med
(2005)
The American-European Consensus Conference on ARDS: definitions, mechanisms, relevant outcomes, and clinical trial coordination
Am J Respir Crit Care Med
Acute respiratory distress syndrome: underrecognition by clinicians and diagnostic accuracy of three clinical definitions
Crit Care Med
Quality improvement report: linking guideline to regular feedback to increase appropriate requests for clinical test; blood gas analysis in intensive care
BMJ
Practice guideline for arterial blood gas measurement in the intensive care unit decreases numbers and increases appropriateness of tests
Crit Care Med
Do changes in pulse oximeter oxygen saturation predict equivalent changes in arterial oxygen saturation?
Crit Care
Potential errors in pulse oximetry: II. Effects of changes in saturation and signal quality
Anaesthesia
Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome: the Acute Respiratory Distress Syndrome Network
N Engl J Med
Arterial oxygenation time after an Fio2increase in mechanically ventilated patients
Am J Respir Crit Care Med
Longitudinal data analysis for discrete and continuous outcomes
Biometrics
Higher versus lower positive end-expiratory pressures in patients with the acute respiratory distress syndrome
N Engl J Med
Pulse oximetry
Intensive Care Med
Cited by (570)
Development and validation of a prediction model for evaluating extubation readiness in preterm infants
2023, International Journal of Medical Informatics
This research was funded by National Institutes of Health grants N01-HR-46054 (to Drs. Rice, Wheeler, and Bernard), N01-HR-46064 (to Mr. Hayden and Dr. Schoenfeld), HL07123 (to Dr. Rice), HL70521 (to Dr. Ware), and HL81332 (to Dr. Ware) from the National Heart, Lung, and Blood Institute.
The authors have reported to the ACCP that no significant conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.