Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học quốc tế cung cấp cho các bạn kiến thức về ngành y đề tài: Bedside quantification of dead-space fraction using routine clinical data in patients with acute lung injury: secondary analysis of two prospective trials. | Siddiki et al. Critical Care 2010 14 R141 http content 14 4 R141 c CRITICAL CARE RESEARCH Open Access Bedside quantification of dead-space fraction using routine clinical data in patients with acute lung injury secondary analysis of two prospective trials 1 2 -2 3 4 2 2 Hassan Siddiki Marija Kojicic Guangxi Li Murat Yilmaz Taylor B Thompson Rolf D Hubmayr Ognjen Gajic Abstract Introduction Dead-space fraction Vd Vt has been shown to be a powerful predictor of mortality in acute lung injury ALI patients. The measurement of Vd Vt is based on the analysis of expired CO2 which is not a part of standard practice thus limiting widespread clinical application of this method. The objective of this study was to determine prognostic value of Vd Vt estimated from routinely collected pulmonary variables. Methods Secondary analysis of the original data from two prospective studies of ALI patients. Estimated Vd Vt was calculated using the rearranged alveolar gas equation Vd Vt 1- VE XPaCO2 where VCQ is the estimated CO2 production calculated from the Harris Benedict equation minute ventilation VE is obtained from the ventilator rate and expired tidal volume and PaCO2 from arterial gas analysis. Logistic regression models were created to determine the prognostic value of estimated Vd Vt. Results One hundred and nine patients in Mayo Clinic validation cohort and 1896 patients in ARDS-net cohort demonstrated an increase in percent mortality for every 10 increase in Vd Vt in a dose response fashion. After adjustment for non-pulmonary and pulmonary prognostic variables both day 1 adjusted odds ratio-OR 95 CI to and day 3 OR 95 CI to estimated dead-space fraction predicted hospital mortality. Conclusions Elevated estimated Vd Vt predicts mortality in ALI patients in a dose response manner. A modified alveolar gas equation may be of clinical value for a rapid bedside estimation of Vd Vt utilizing routinely collected clinical data.
