Hospital acquired pneumonia (HAP) and ventilatorassociated pneumonia (VAP) are common hospital-acquired infections with higher mortality, longer hospital stay and more hospitalization expenses. With the latest research results and evidence-based guideline methodology, Infectious Diseases Society of America (IDSA) and American Thoracic Society (ATS) have collaborated to create updated guidelines for the diagnosis and treatment of HAP and VAP in 2016. It is worth critically reading and thinking that most recommendations are supported by low-quality or very-low quality evidence and some strong recommendations is different from the actual clinical work in China. We will focus on these topics that are associated closely with clinical practice and inconsistent with the current implementation in China to provide better understanding of the guideline.

Sedation and analgesia for ventilated patients is an important treatment in intensive care unit (ICU). Patients receiving mechanical ventilation therapy comfortably and safely can improve patient-ventilator synchrony, reduce ventilation-related lung injury (VILI), improve compliance, decrease oxygen consumption and stress, prevent accidents, and reduce the incidence of complications and mortality in critical patients. Although sedation mayprotect lung function, it also has a greater impact on respiratory function. Therefore, based on domestic and overseas related researches about sedation therapy in ventilated patients, we expounded on the effects of sedation therapy, different sedatives and different sedative methods on respiratory function of ventilated patients. The effects of sedation improving patient-ventilator synchrony or protecting pulmonary function as well as problems about inhibition of spontaneous respiration or delayed extubation were discussed to provide references for sedation treatment in patients with mechanical ventilation.

Objective To compare the efficiency of acute physiology and chronic health evaluation (APACHE)Ⅱ and Ⅳ in mortality risk prediction of severe acute pancreatitis (SAP).Methods From January 2013 to December 2014,SAP patients admitted to intensive care units (ICU) were retrospectively analyzed in single center.The clinical data of the first 24 hours since the patients admitted into ICU were collected.The modified Marshall score,APACHE Ⅱ and APACHE Ⅳ score were calculated.The mortality risk predictive value of each patient was calculated by APACHE Ⅱ and APACHE Ⅳ.According to the final clinical outcome of patients,Hosmer-Lemeshow was performed to compare real mortality rate with predictive mortality rate,and calibration of APACHE Ⅱ and APACHE Ⅳ in the mortality risk of each patients was evaluated.The resoluation of the two scoring systems was compared by the area under the receiver operator characteristic curve (AUC).Results In the end,192 patients (152(79.2％) survivors and 40(20.8％) dead) were enrolled.Modified Marshall score,APACHE Ⅱ score and APACHE Ⅳ score of patients in dead group was 6.30±0.36,21.3±8.0 and 88.1± 30.2,respectively;and those of survival group was 3.70 ± 0.20,12.3 ± 5.6 and 53.4 ± 19.0,respectively,and the differences between two groups were statistically significant (t-6.436、-6.683、-6.913,all P＜ 0.01).The results of Hosmer-Lemeshowin calibration of APACHE Ⅱ and APACHE Ⅳ indicated that both two systems could predict mortality risk of SAP patients well (P＞ 0.05).The AUC of APACHE Ⅱ score (cut-off ≥26) and APACHE Ⅳ score (cut off≥91) was 0.81(95％CI 0.74 to 0.89) and 0.83(95％CI 0.75 to 0.90),respectively,and the difference was not statistically significant (x2 =0.21,P=0.644),which indicated that there was no statistically significant difference in calibration.Conclusions APACHE Ⅳ scoring system is not better than APACHE Ⅱ scoring system in prognosis prediction of SAP patients.The prognosis of SAP patients could be accurately evaluated by APACHE Ⅱ.

Objective There are two main functions of gastrointestinal tract,digestion and absorption,and barrier function.The latter has an important defensive effect,which keeps the body away from the invading and damaging of bacteria and endotoxin.It maintains the systemic homeostasis.Intestinal dysfunction would happen when body suffers from diseases or harmful stimulations.The more serious intestinal disorders would harm the intestinal protective mechanism,or intestinal barrier function,and bacterial/endotoxin translocation,of intestinal failure(IF) would ensue.This article provides a critical review of the evidence indicating that an increase in bacterial translocation is associated with sepsis,and even the multiple organ failure syndrome in critically ill patients.The in-transit microorganisms play an essential role in the homeostasis of local and systemic immunity.Methods All studies published from 2000 to June 2005 about intestinal permeability,bacterial translocation,and systemic inflammatory response syndrome were located by search of PubMed.Results Clinical and experimental studies investigating the correlation between bacterial translocation and systemic inflammatory response syndrome,associated with the damage of the gut barrier function.To keep the mucosal barrier function intact is one of the main issues in the prevention of bacterial translocation.This could be achieved by the adequate delivery of oxygen and nutrient supplementation to the gut.Enteral nutrition,probiotic can be a good choice.Conclusion With a better understanding of the bacteria-host interactions in health and the alterations induced by critical illness,new therapies that improve the environment of both may lead to better recovery rates in intensive care unit patients.

Objective To discuss the mechanism of growth hormone (GH) in infection and its safety. Methods Advances in the application of GH in infection of recent years were reviewed. Results In infectious patients, GH may promote protein synthesis, strengthen the immunity of body, and protect the integrity of intestinal barrier function. But some patients present GH resistance. The safety of GH for infectious patients needs further evaluation. Conclusion GH may play a supplementary role in infection therapy, but further research is needed.

Objective To discuss the feasibility and safety of early enteral nutrition (EN) on treatment of severe acute pancreatitis (SAP) and its influence. Methods The advancement about application of early EN on treatment of SAP in recent years were reviewed. Results In patients with SAP, early EN via catheter placed in the jejunum could protect the integrity of intestinal barrier and reduce infectious complications. But no consensus had been reached about the starting time, ingredient and infusion mode yet. Conclusion Early EN may have positive effects on treatment of SAP, but further researches are still needed.

Critical Illness ; therapy ; Fluid Therapy ; Humans

Clinical education for undergraduates in China can be divided into three phases:preclinical phase,clinical clerkship phase,clinical practice phase,and each phase has its own features and different teaching tasks.Currently there are four teaching methods mostly applied in clinical education:lecture-based Learning (LBL),team-based learning (TBL),case-based learning (CBL) and problem-based learning (PBL).LBL is a teacher-centered.teaching method,which focuses on making knowledge accurate,systematic and comprehensive;TBL,CBL and PBL are student-centered teaching methods,which can improve students' enthusiasm and subject initiative.Each teaching method has advantages and dis-advantages.According to the different characteristics of three stages of medical education,this paper analyzes the reasonable application of different medical teaching methods in three stages of undergraduate medical education:in preclinical stage,combining LBL with TBL teaching methods;in clinical clerkship phase,combining the teaching methods of LBL,TBL and CBL;in clinical practice stage,combining CBL with PBL teaching methods.

BACKGROUND:The strength of al-ceramic crowns is affected by many factors. At present there are many studies concerning the neck edge shape, cutting thickness, binder and convergence angle, but little has been reported on the effects of different occlusions on al-ceramic crowns. OBJECTIVE:To explore the maxilary central incisor al-ceramic crowns in different occlusal states by finite element analysis. METHODS: Three-dimensional finite element models of the maxilary central incisor al-ceramic crowns were established. Empress II and In-Ceram Zirconia were selected. The normal overbite position and deep overbite position were applied to force a load of 230 N, with the long axis of the tooth at a 45° angle. Distribution of inner stress and edge stress was analyzed at different occlusal states. RESULTS AND CONCLUSION:(1) The stress distribution of al-ceramic crowns under different occlusion relationship was different. The stress peaks of cementum, alveolar bone and periodontium in the deep overbite were lower than those in the normal overbite. The stress peaks of al-ceramic crowns and binder were higher than in the deep overbite than the normal overbite. The stress peak of the dentin in the Empress II group was higher in the deep overbite than in the normal overbite. The stress peak of the dentin in the In-Ceram Zirconia group was lower in the deep overbite than in the normal overbite. Different al-ceramic crowns had no influence on the stress distribution, but in the deep overbite, the stress was mainly concentrated in the occlusal contact area, and in the normal overbite, the stress was mainly concentrated in the occlusal contact area and at the labial cervical margin. (2) The stress distribution of different al-ceramic crowns under the same occlusal state was different. In the normal overbite, different al-ceramic crowns had no evident influence on the stress peak, and in the deep overbite, there was a certain effect of different al-ceramic crowns on the stress peak, but there was no significant difference. The stress peaks of blinder and dentin were obviously affected by al-ceramic crowns. The stress peaks of blinder and dentin in Empress II group were higher than those in the In-Ceram Zirconia group.