OBJECTIVETo detect the levels of dipalmitoyl phosphatidyl choline (DPPC) in the sputum of the patients with acute cerebral injury without primary pulmonary injury after mechanical ventilation treatment.

METHODSDPPC levels in sputum of 35 patients with acute cerebral injury but without pulmonary injury were detected with high performance liquid chromatography at the beginning of ventilation and 16-20 days, 21-40 days, and 41-60 days after ventilation, respectively.

RESULTSThere was no significant difference of the DPPC levels between 16-20 days after ventilation (3.36+/-0.49) and at the beginning of ventilation (3.37+/-0.58) (P>0.05). The mean levels of DPPC decreased significantly at 21-40 days (2.87 mg/ml+/-0.26 mg/ml, P<0.05) and 41-60 days (1.93 mg/ml+/-0.21 mg/ml, P<0.01) after ventilation compared with that at the beginning of ventilation. At the same period, the peak inspiratory pressure and the mean pressure of airway increased significantly, whereas the static compliance and the partial pressure of oxygen in artery decreased significantly. Among the 25 patients who received ventilation for more than 20 days, 8 (32%) had slightly-decreased partial pressure of oxygen in artery compared with that at the beginning of ventilation.

CONCLUSIONSMechanical ventilation can decrease the DPPC levels, decrease the lung compliance and increase the airway pressure, even impair the oxygenation function in patients with acute cerebral injury. Abnormal DPPC is one of the major causes of ventilator-associated lung injury.

1,2-Dipalmitoylphosphatidylcholine ; metabolism ; Acute Disease ; Adolescent ; Adult ; Brain Injuries ; physiopathology ; Chromatography, High Pressure Liquid ; Female ; Humans ; Male ; Respiration, Artificial ; Sputum ; metabolism

OBJECTIVE: To develop and validate a user-friendly risk score for older mitral regurgitation (MR) patients, referred to as the Elder-MR score. METHODS: The China Senile Valvular Heart Disease (China-DVD) Cohort Study functioned as the development cohort, while the China Valvular Heart Disease (China-VHD) Study was employed for external validation. We included patients aged 60 years and above receiving medical treatment for moderate or severe MR (2274 patients in the development cohort and 1929 patients in the validation cohort). Candidate predictors were chosen using Cox's proportional hazards model and stepwise selection with Akaike's information criterion. RESULTS: Eight predictors were identified: age ≥ 75 years, body mass index < 20 kg/m², NYHA class III/IV, secondary MR, anemia, estimated glomerular filtration rate < 60 mL/min per 1.73 m², albumin < 35 g/L, and left ventricular ejection fraction < 60%. The model displayed satisfactory performance in predicting one-year mortality in both the development cohort (C-statistic = 0.73, 95% CI: 0.69-0.77, Brier score = 0.06) and the validation cohort (C-statistic = 0.73, 95% CI: 0.68-0.78, Brier score = 0.06). The Elder-MR score ranges from 0 to 15 points. At a one-year follow-up, each point increase in the Elder-MR score represents a 1.27-fold risk of death (HR = 1.27, 95% CI: 1.21-1.34, P < 0.001) in the development cohort and a 1.24-fold risk of death (HR = 1.24, 95% CI: 1.17-1.30, P < 0.001) in the validation cohort. Compared to EuroSCORE II, the Elder-MR score demonstrated superior predictive accuracy for one-year mortality in the validation cohort (C-statistic = 0.71 vs. 0.70, net reclassification improvement = 0.320, P < 0.01; integrated discrimination improvement = 0.029, P < 0.01). CONCLUSIONS The Elder-MR score may serve as an effective risk stratification tool to assist clinical decision-making in older MR patients.