At present,the strategy of setting the optimal positive end-expiratory pressure(PEEP)for mechani-cal ventilation still needs further clinical exploration.Electrical impedance tomography(EIT)is a newly devel-oped technology at the end of the 20th century.It can monitor pulmonary ventilation in real time,so is exten-sively important to optimal PEEP setting.This review summarizes the principles of using EIT to guide PEEP setting,monitoring respiratory system compliance,spatial distribution,temporal distribution,local lung perfu-sion and other information published in recent years,analyzes the basic and clinical research information relat-ed to PEEP effect and its application in individualized PEEP setting.

The incidence and mortality of venous thromboembolism (VTE) are high in critically ill patients, and there is still a risk of VTE and bleeding after the use of fixed-dose low molecular weight heparin (LMWH) for prophylaxis. The level of anti-factor Ⅹa is not up to standard after LMWH prophylaxis in patients with surgery or trauma. The condition of critically ill patients is complicated, and the proportion of patients with low antithrombin Ⅲ is high, which can affect the prophylactic efficacy of LMWH and contribute to VTE occurrence. There is currently no consensus on whether adjusting LMWH dose according to anti-factor Ⅹa levels can reduce VTE occurrence in critically ill patients. High-quality multicenter randomized controlled studies are needed in the future to establish new approaches for precise prevention of VTE in critically ill patients.

BACKGROUND: The aim of this study was to analyze the incidence of lower limb deep venous thrombosis (DVT) and the corresponding coagulation status in severe patients after thoracic surgery. METHODS: Severe patients after thoracic surgery who received mechanical prophylaxis of lower limb DVT between July 2016 and June 2018 were analysed retrospectively. Their general information, disease species, surgical treatment, and coagulation index were reviewed. RESULTS: Fifty patients were finally included. There were 34 male and 16 female, aging from 22 to 80 years. The incidence of DVT was 22.0%, all of them were isolated calf DVT. The incidence was 29.4% in male patients, while 6.3% in female; 23.5% in malignant diseases and 18.6% in benign. All coagulation index presented no statistical difference between patients with and without DVT, except activated partial thromboplastin time (APTT). CONCLUSIONS Even on the basis of adequate mechanical prophylaxis, lower limb DVT is common in severe patients after thoracic surgery. Meanwhile, male patients and malignant diseases are more suscepted.
Adult ; Aged ; Aged, 80 and over ; Blood Coagulation ; Female ; Humans ; Incidence ; Lower Extremity ; blood supply ; Lung Neoplasms ; surgery ; Male ; Middle Aged ; Retrospective Studies ; Thoracic Surgical Procedures ; adverse effects ; Venous Thrombosis ; etiology ; physiopathology ; Young Adult