ObjectiveTo investigate the prevalence and risk factors of deep venous thrombosis (DVT) in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD). MethodsOne hundred and eight patients with acute exacerbation of COPD admitted between March 2009 and September 2010 were consecutively included.On admission,color Doppler ultrasound examination of lower extremities was performed for diagnosing DVT in all cases.The patients with DVT were compared with those without DVT in demographics,symptoms,physical signs,risk factors and laboratory examination including Ⅷ factor and von Willebrand factor (VWF). ResultsAmong 108 patients with acute exacerbation of COPD,DVT was detected in 11 cases (10.1%).In the COPD patients with DVT,the duration of hospitalization was longer (P<0.001) and the mechanical ventilation requirement increased (P=0.024) compared those without DVT.Other indicators for more possibility of DVT were immobility over 3 days (P=0.001),pneumonia as concomitance (P=0.004),type Ⅱ respiratory failure (P=0.011),and current smoking (P=0.002).The plasma leukocytes,D-dimer and Ⅷ factor levels were significantly higher in the COPD patients with DVT than those without DVT (P=0.005;P<0.001;P=0.009). ConclusionThe incidence of DVT in patients with acute exacerbation of COPD is 10.1%.The prevalence of DVT is higher in distal extremities than that in proximal,especially the intermuscular veins.The patients with acute exacerbation of COPD have a higher risk of DVT when immobilized over 3 days,complicated by pneumonia or type Ⅱ respiratory failure,and having a high levels of plasma leukocytes,D-dimer and Ⅷ factor.
ObjectiveTo investigate the physiologic effects of different pressure assist (PA) on ventilatory status,oxygenation and work of breathing (WOB) when a new generation of proportional assist ventilation (PAV) is applied in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). MethodsA prospective,crossover randomized physiologic study was performed.80%PA,60%PA and 40%PA was sequentially randomized to be applied with the duration of 30 minutes,and pressure support ventilation (PSV) with the duration of 30 minutes was applied before each PA.Ventilatory status, oxygenation,dyspnea indexes in PSV and different PA were compared,and WOB of patients and ventilator were compared in different PA. ResultsTwenty-eight patients were recruited into the study.With the decrease of PA,peak inspiratory pressure (PIP),mean airway pressure (Pm),and tidal volume (VT) decreased gradually (P>0.05),respiratory rate (RR) increased gradually (P<0.05),while minute volume (MV),heart rate (HR),systolic blood pressure (SBP),mean arterial pressure (MAP),pH,arterial carbon dioxide tension (PaCO2),and arterial oxygen tension/inspired oxygen fraction (PaO2/FiO2) did not change significantly (P>0.05).Compared with PSV mode,PIP increased significantly in 80%PA (P<0.05),decreased significantly in 60%PA and 40%PA (P<0.05).Pm did not change significantly in 80%PA (P>0.05),decreased significantly in 60%PA and 40%PA (P<0.05).VT increased significantly in 80%PA (P<0.05),decreased significantly in 60%PA and 40%PA (P<0.05).RR did not change significantly in 80%PA (P>0.05),increased significantly in 60%PA and 40%PA (P<0.05).MV did not change significantly in 80%PA (P>0.05),decreased significantly in 60%PA and 40%PA (P<0.05).With the decrease of PA,Borg score and scale for accessory muscle use increased gradually (P<0.05).Compared with PSV mode,Borg score and scale for accessory muscle use did not change significantly in 80%PA (P>0.05),increased significantly in 60%PA and 40%PA (P<0.05).WOB of patients in 40%PA was significantly higher than that in 60%PA (P=0.000) and that in 80%PA (P=0.000),while which in 60%PA was significantly higher than that in 80%PA (P=0.000).On the contrary,WOB of ventilator in 40%PA was significantly lower than that in 60%PA (P=0.004) and that in 80%PA (P=0.000),while which in 60%PA was significantly lower than that in 80%PA (P=0.000). ConclusionThe new generation of PAV can safely and effectively provide respiratory support to patients with AECOPD.Respiratory pattern,levels of dyspnea and accessory muscle use in 80%PA are similar with those in PSV.With the decrease of PA,levels of spontaneous breathing and WOB increase and dyspnea worsens.PAV can promote spontaneous breathing and prevent respiratory muscle disuse atrophy even more, but easily lead to respiratory muscle fatigue with inappropriate use.
ObjectiveTo explore the early predictive value of Wells score and D-dimer for acute pulmonary embolism. MethodsEighty-two cases with acute pulmonary embolism comfirmed by computed tomography pulmonary angiography and (or) lung ventilation/perfusion scan were retrospectively studied from October 2013 to October 2014 in our hospital. Another 82 cases without acute pulmonary embolism in the chest pain center simultaneously were selected as control group. The data on admission were analyzed including Wells score, D-dimer, pH, PCO2, PO2, P(A-a)O2, brain natriuretic peptide, troponin I of two groups of patients. Relevant variables were selected by multivariate logistic regression analysis. The receiver operating characteristic (ROC) curve was made by sensitivity as the ordinate and 1 minus specificity as abscissa. The area under ROC curve (AUC) for relevant variables was calculated and the variable with higher AUC was selected. The best threshold, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were achieved from the ROC curves. ResultsThe multivariate logistic regression analysis showed that Wells score (OR=8.114, 95%CI 1.894-34.761, P=0.005) and D-dimer (OR=1.009, 95%CI 1.001-1.017, P=0.021) could predict APE early. The AUC, sensitivity, specificity, PPV, NPV of Wells score for the early prediction of patients with acute pulmonary embolism were 0.990, 50.0%, 100.0%, 100.0%, 66.7%, respectively. The AUC, sensitivity, specificity, PPV, NPV of D-dimer for the early prediction of patients with acute pulmonary embolism were 0.986, 95.1%, 97.6%, 97.5%, 95.2%, respectively. ConclusionWells score and D-dimer have high predictive value in patients with acute pulmonary embolism, and can be used in preliminary screening of acute pulmonary embolism in the emergency department.