title: Prediction of inspired oxygen fraction for targeted arterial oxygen tension following open heart surgery in non-smoking and smoking patients.
abstract: Simple and accurate expressions describing the PaO2-FiO2relationship in mechanically ventilated patients are lacking. The current study aims to validate a novel mathematical expression for accurate prediction of the fraction of inspired oxygen that will result in a targeted arterial oxygen tension in non-smoking and smoking patients receiving mechanical ventilation following open heart surgeries. One hundred PaO2-FiO2data pairs were obtained from 25 non-smoking patients mechanically ventilated following open heart surgeries. One data pair was collected at each of FiO2of 40, 60, 80, and 100% while maintaining same mechanical ventilation support settings. Similarly, another 100 hundred PaO2-FiO2data pairs were obtained from 25 smoking patients mechanically ventilated following open heart surgeries. The utility of the new mathematical expression in accurately describing the PaO2-FiO2relationship in these patients was assessed by the regression and Bland-Altman analyses. Significant correlations were seen between the true and estimated FiO2values in non-smoking (r2= 0.9424; p < 0.05) and smoking (r2= 0.9466; p < 0.05) patients. Tight biases between the true and estimated FiO2values for non-smoking (3.1%) and smoking (4.1%) patients were observed. Also, significant correlations were seen between the true and estimated PaO2/FiO2ratios in non-smoking (r2= 0.9530; p < 0.05) and smoking (r2= 0.9675; p < 0.05) patients. Tight biases between the true and estimated PaO2/FiO2ratios for non-smoking (-18 mmHg) and smoking (-16 mmHg) patients were also observed. The new mathematical expression for the description of the PaO2-FiO2relationship is valid and accurate in non-smoking and smoking patients who are receiving mechanical ventilation for post cardiac surgery.
authors: Division of Pulmonary and Critical Care, Department of Medicine, American University of Beirut, Beirut, Lebanon.
authors: Pierre
authors: P
authors: Bou-Khalil
authors: Division of Pulmonary and Critical Care, Department of Medicine, American University of Beirut, Beirut, Lebanon.
authors: Salah
authors: S
authors: Zeineldine
authors: Institution of Respiratory Research, Cleveland Clinic Foundation, Cleveland, OH, USA.
authors: Robert
authors: R
authors: Chatburn
authors: Department of Anesthesiology, Medical Center, American University of Beirut, P.O.Box:11-0236, Beirut, 1107-2020, Lebanon.
authors: Chakib
authors: C
authors: Ayyoub
authors: School of Medicine, American University of Beirut, Beirut, Lebanon.
authors: Farouk
authors: F
authors: Elkhatib
authors: Division of Pulmonary and Critical Care, Department of Medicine, American University of Beirut, Beirut, Lebanon.
authors: Imad
authors: I
authors: Bou-Akl
authors: Department of Anesthesiology, Medical Center, American University of Beirut, P.O.Box:11-0236, Beirut, 1107-2020, Lebanon. mk05@aub.edu.lb.
authors: Mohamad
authors: M
authors: El-Khatib
mesh_terms: D000328:Adult; D000368:Aged; D001784:Blood Gas Analysis; D015992:Body Mass Index; D006348:Cardiac Surgical Procedures / Q000379:methods*; D005260:Female; D006801:Humans; D001239:Inhalation; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D010100:Oxygen; D010313:Partial Pressure; D011659:Pulmonary Gas Exchange; D012044:Regression Analysis; D012121:Respiration, Artificial / Q000379:methods*; D012907:Smoking; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: Open heart; Oxygen; PaO2/FiO2 ratio; Partial pressure of oxygen