RESUMEN
Simple and accurate expressions describing the PaO2-FiO2 relationship 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-FiO2 data pairs were obtained from 25 non-smoking patients mechanically ventilated following open heart surgeries. One data pair was collected at each of FiO2 of 40, 60, 80, and 100% while maintaining same mechanical ventilation support settings. Similarly, another 100 hundred PaO2-FiO2 data 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-FiO2 relationship in these patients was assessed by the regression and Bland-Altman analyses. Significant correlations were seen between the true and estimated FiO2 values 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 FiO2 values for non-smoking (3.1%) and smoking (4.1%) patients were observed. Also, significant correlations were seen between the true and estimated PaO2/FiO2 ratios 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/FiO2 ratios for non-smoking (-18 mmHg) and smoking (-16 mmHg) patients were also observed. The new mathematical expression for the description of the PaO2-FiO2 relationship is valid and accurate in non-smoking and smoking patients who are receiving mechanical ventilation for post cardiac surgery.
Asunto(s)
Análisis de los Gases de la Sangre , Procedimientos Quirúrgicos Cardíacos/métodos , Inhalación , Oxígeno , Presión Parcial , Respiración Artificial/métodos , Fumar , Adulto , Anciano , Índice de Masa Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Teóricos , Intercambio Gaseoso Pulmonar , Análisis de Regresión , Adulto JovenRESUMEN
Isolated collapse of the left ventricle (LV) in diastole is not a very common finding on two-dimensional echocardiography. Reported cases in the literature were due to either loculated postoperative pericardial effusion/hematoma or left pleural effusion. To our knowledge, this is the first case report of LV diastolic collapse secondary to extra-thoracic compression.
