First screening for tick-borne pathogens in Chinese Milu deer (Elaphurus davidianus).

Ticks are primary vectors for many tick-borne pathogens (TBPs) and pose a serious threat to veterinary and public health. Information on the presence of TBPs in Chinese Milu deer (Elaphurus davidianus) is limited. In this study, a total of 102 Chinese Milu deer blood samples were examined for Anaplasma spp., Theileria spp., Babesia spp., Rickettsia spp., and Borrelia spp., and three TBPs were identified: Anaplasma phagocytophilum (48; 47.1 %), Candidatus Anaplasma boleense (47; 46.1%), and Theileria capreoli (8; 7.8 %). Genetic and phylogenetic analysis of the 16S rRNA and 18S rRNA confirmed their identity with corresponding TBPs. To our knowledge, this is the first report on Candidatus A. boleense and T. capreoli detection in Chinese Milu deer. A high prevalence of A. phagocytophilum with veterinary and medical significance was identified in endangered Chinese Milu deer, which could act as potential zoonotic reservoirs. The identification of the TBPs in Chinese Milu deer provides useful information for the prevention and control of tick-borne diseases.

Development and application of an indirect ELISA to detect antibodies to Neospora caninum in cattle based on a chimeric protein rSRS2-SAG1-GRA7.

Neospora caninum is an important apicomplexan parasite causing neosporosis in cattle. The disease is recognized as one of the most important cause of reproductive problems and abortion in cattle worldwide. In this context, we developed an indirect enzyme-linked immunosorbent assays (ELISA) with chimeric protein rSRS2-SAG1-GRA7 to diagnose antibodies to Neospora-infection. This indirect ELISA was compared to indirect fluorescent antibody test (IFAT) and western blotting (WB), and the sensitivity and specificity results of ELISA were calculated to be 86.7 and 96.1%, respectively. The overall coincidence rate was 92.6% using IFAT and WB. Additionally, 329 aborting dairy cattle serum samples were tested using this ELISA to evaluate the prevalence of N. caninum in Ningxia, China. The positive rate of N. caninum in these farms was from 19.05 to 57.89%, and the mean rate was 41.64% (±11.01%), indicating that infection with N. caninum may be one of the important causes of cattle abortion in this region. This established rSRS2-SAG1-GRA7 indirect ELISA is capable for detecting the antibodies against N. caninum, and it could be a useful screening tool for monitoring the epidemiology of neosporosis in cattle.

mTORC2 Activation Mediated by Mesenchymal Stem Cell-Secreted Hepatocyte Growth Factors for the Recovery of Lipopolysaccharide-Induced Vascular Endothelial Barrier.

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is characterized by pulmonary microvascular endothelial barrier dysfunction. Mesenchymal stem cell-secreted hepatocyte growth factor (HGF) has positive effects of lipopolysaccharide- (LPS-) induced pulmonary endothelial barrier. Studies have exhibited the mammalian TORC1 (mTORC1) signaling is of potent angiogenesis effects. The mTOR protein kinase has two distinct multiprotein complexes mTORC1 and mTORC2 that regulate different branches of the mTOR network. However, detailed mTORC2 mechanisms of HGF protective effects remain poorly defined. Therefore, the aim of this study was to determine whether mTORC2 mediated protective effects of MSC-secreted HGF against LPS-induced pulmonary microvascular endothelial barrier dysfunction activated like mTORC1 activation. We introduced MSC-PMVEC coculture transwell system and recombinant murine HGF on LPS-induced endothelial cell barrier dysfunction in vitro and then explored potential mechanisms by lentivirus vector-mediated HGF, mTORC1 (raptor), and mTORC2 (rictor) gene knockdown modification. Endothelial paracellular and transcellular permeability, adherent junction protein (VE-Cadherin), cell proliferation, apoptosis, and mTOR-associated proteins were tested. These revealed that HGF could promote quick reestablishment of adherent junction VE-cadherin and decrease endothelial paracellular and transcellular permeability during LSP-induced endothelial dysfunction with the involvement of mTORC2 (rictor) and mTORC1 (raptor) pathways. Raptor and rictor knockdown in LPS-induced PMEVECs with stimulation of HGF increased apoptosis ratio, activated Cleaved-Caspase-3 expression, and downregulated cell proliferation. Moreover, mTORC2/Akt but not mTORC2/PKC had significance on HGF endothelial protective effects. Taken together, these highlight activation mTORC2 pathway could also contribute to vascular endothelial barrier recovery by MSC-secreted HGF in LPS stimulation.

Nucleotide polymorphism in ARDS outcome: a whole exome sequencing association study.

BACKGROUND: Genetic locus were identified associated with acute respiratory distress syndrome (ARDS). Our goal was to explore the associations between genetic variants and ARDS outcome, as well as subphenotypes. METHODS: This was a single-center, prospective observational trial enrolling adult ARDS patients. After baseline data were collected, blood samples were drawn to perform whole exome sequencing, single nucleotide polymorphism (SNP)/insertion-deletion to explore the quantitative and functional associations between genetic variants and ICU outcome, clinical subphenotypes. Then the lung injury burden (LIB), which was defined as the ratio of nonsynonymous SNP number per megabase of DNA, was used to evaluate its value in predicting ARDS outcome. RESULTS: A total of 105 ARDS patients were enrolled in the study, including 70 survivors and 35 nonsurvivors. Based on the analysis of a total of 65,542 nonsynonymous SNP, LIB in survivors was significantly higher than nonsurvivors [1,892 (1,848-1,942)/MB versus 1,864 (1,829-1,910)/MB, P=0.018], while GO analysis showed that 60 functions were correlated with ARDS outcome, KEGG enrichment analysis showed that SNP/InDels were enriched in 13 pathways. Several new SNPs were found potentially associated with ARDS outcome. Analysis of LIB was used to determine its outcome predicting ability, the area under the ROC curve of which was only 0.6103, and increase to 0.712 when combined with APACHE II score. CONCLUSIONS: Genetic variants are associated with ARDS outcome and subphenotypes; however, their prognostic value still need to be verified by larger trials. TRIAL REGISTRATION: Clinicaltrials.gov NCT02644798. Registered 20 April 2015.

Effects of Propofol on Respiratory Drive and Patient-ventilator Synchrony during Pressure Support Ventilation in Postoperative Patients: A Prospective Study.

BACKGROUND: Propofol is increasingly used during partial support mechanical ventilation such as pressure support ventilation (PSV) in postoperative patients. However, breathing pattern, respiratory drive, and patient-ventilator synchrony are affected by the sedative used and the sedation depth. The present study aimed to evaluate the physiologic effects of varying depths of propofol sedation on respiratory drive and patient-ventilator synchrony during PSV in postoperative patients. METHODS: Eight postoperative patients receiving PSV for <24 h were enrolled. Propofol was administered to achieve and maintain a Ramsay score of 4, and the inspiratory pressure support was titrated to obtain a tidal volume (VT) of 6-8 ml/kg. Then, the propofol dose was reduced to achieve and maintain a Ramsay score of 3 and then 2. At each Ramsay level, the patient underwent 30-min trials of PSV. We measured the electrical activity of the diaphragm, flow, airway pressure, neuro-ventilatory efficiency (NVE), and patient-ventilator synchrony. RESULTS: Increasing the depth of sedation reduced the peak and mean electrical activity of the diaphragm, which suggested a decrease in respiratory drive, while VT remained unchanged. The NVE increased with an increase in the depth of sedation. Minute ventilation and inspiratory duty cycle decreased with an increase in the depth of sedation, but this only achieved statistical significance between Ramsay 2 and both Ramsay 4 and 3 (P < 0.05). The ineffective triggering index increased with increasing sedation depth (9.5 ± 4.0%, 6.7 ± 2.0%, and 4.2 ± 2.1% for Ramsay 4, 3, and 2, respectively) and achieved statistical significance between each pair of depth of sedation (P < 0.05). The depth of sedation did not affect gas exchange. CONCLUSIONS: Propofol inhibits respiratory drive and deteriorates patient-ventilator synchrony to the extent that varies with the depth of sedation. Propofol has less effect on breathing pattern and has no effect on VT and gas exchange in postoperative patients with PSV.

Epidemiological Study of Sepsis in China: Protocol of a Cross-sectional Survey.

BACKGROUND: Sepsis is the leading cause of death among critically ill patients. Herein, we conducted a national survey to provide data on epidemiology and treatment of sepsis in the clinical practice in China, which has no detailed epidemiological data available on sepsis. METHODS: This was a prospective cross-sectional survey from December 1, 2015 to January 31, 2016 in all provinces/municipalities of the mainland of China. The primary outcome of this study was the incidence of sepsis, and the secondary outcome was its etiology in China. Patients with sepsis admitted to the Intensive Care Units were included in this study. The demographic, physiological, bacteriological, and therapeutic data of these patients were recorded. The incidence of sepsis was estimated using the data from the sixth census in China, reported by the Chinese National Health and Family Planning Commission and the National Bureau of Statistics as the standard population. The independent risk factors for increased mortality from sepsis were calculated. CONCLUSIONS: This study indicated the incidence and outcome of sepsis in China. It also showed the most common etiology of different sites and types of infection, which could guide empiric antibiotic therapy. Moreover, it provided information on the independent risk factors for increased mortality due to sepsis. The findings provide evidence to guide clinical management and may help improve the outcome in septic patients. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02448472; https://clinicaltrials.gov/show/NCT02448472.

Hepatic Perfusion Alterations in Septic Shock Patients: Impact of Early Goal-directed Therapy.

BACKGROUND: Early goal-directed therapy (EGDT) has become an important therapeutic management in early salvage stage of septic shock. However, splenic organs possibly remained hypoperfused and hypoxic despite fluid resuscitation. This study aimed to evaluate the effect of EGDT on hepatic perfusion in septic shock patients. METHODS: A prospective observational study was carried out in early septic shock patients who were admitted to Intensive Care Unit within 24 h after onset and who met all four elements of the EGDT criteria after treatment with the standard EGDT procedure within 6 h between December 1, 2012 and November 30, 2013. The hemodynamic data were recorded, and oxygen metabolism and hepatic functions were monitored. An indocyanine green clearance test was applied to detect the hepatic perfusion. The patients' characteristics were compared before treatment (T0), immediately after EGDT (T1), and 24 h after EGDT (T2). This study is registered at ClinicalTrials.org, NCT02060773. RESULTS: Twenty-one patients were included in the study; however, the hepatic perfusion data were not included in the analysis for two patients; therefore, 19 patients were eligible for the study. Hemodynamics data, as monitored by pulse-indicator continuous cardiac output, were obtained from 16 patients. There were no significant differences in indocyanine green plasma disappearance rate (ICG-PDR) and 15-min retention rate (R15) at T0 (11.9 ± 5.0%/min and 20.0 ± 13.2%), T1 (11.4 ± 5.1%/min and 23.6 ± 14.9%), and T2 (11.0 ± 4.5%/min and 23.7 ± 15.3%) (all P > 0.05). Both of the alterations of ICG-PDR and R15 showed no differences at T0, T1, and T2 in the patients of different subgroups that achieved different resuscitation goal numbers when elected (P > 0.05). CONCLUSION: There were no hepatic perfusion improvements after EGDT in the early phase of patients with septic shock. TRIAL REGISTRATION: Clinicaltrials.gov NCT02060773 (https://clinicaltrials.gov/ct2/show/NCT02060773).

Comparison of the effects of albumin and crystalloid on mortality in adult patients with severe sepsis and septic shock: a meta-analysis of randomized clinical trials.

INTRODUCTION: The aim of this study was to examine whether albumin reduced mortality when employed for the resuscitation of adult patients with severe sepsis and septic shock compared with crystalloid by meta-analysis. METHODS: We searched for and gathered data from MEDLINE, Elsevier, Cochrane Central Register of Controlled Trials and Web of Science databases. Studies were eligible if they compared the effects of albumin versus crystalloid therapy on mortality in adult patients with severe sepsis and septic shock. Two reviewers extracted data independently. Disagreements were resolved by discussion with other two reviewers until a consensus was achieved. Data including mortality, sample size of the patients with severe sepsis, sample size of the patients with septic shock and resuscitation endpoints were extracted. Data were analyzed by the methods recommended by the Cochrane Collaboration Review Manager 4.2 software. RESULTS: A total of 5,534 records were identified through the initial search. Five studies compared albumin with crystalloid. In total, 3,658 severe sepsis and 2,180 septic shock patients were included in the meta-analysis. The heterogeneity was determined to be non-significant (P = 0.86, I(2) = 0%). Compared with crystalloid, a trend toward reduced 90-day mortality was observed in severe sepsis patients resuscitated with albumin (odds ratio (OR) 0.88; 95% CI, 0.76 to 1.01; P = 0.08). However, the use of albumin for resuscitation significantly decreased 90-day mortality in septic shock patients (OR 0.81; 95% CI, 0.67 to 0.97; P = 0.03). Compared with saline, the use of albumin for resuscitation slightly improved outcome in severe sepsis patients (OR 0.81; 95% CI, 0.64 to 1.08; P = 0.09). CONCLUSIONS: In this meta-analysis, a trend toward reduced 90-day mortality was observed in severe sepsis patients resuscitated with albumin compared with crystalloid and saline. Moreover, the 90-day mortality of patients with septic shock decreased significantly.

[The effect of stress dose glucocorticoid on patients with acute respiratory distress syndrome combined with critical illness-related corticosteroid insufficiency].

OBJECTIVE: To investigate the effect of stress dose glucocorticoid on patients with acute respiratory distress syndrome (ARDS) combined with critical illness-related corticosteroid insufficiency (CIRCI). METHODS: All early ARDS patients combined with CIRCI were screened by an adrenal corticotrophic hormone (ACTH) test and randomly divided into treatment group (hydrocortisone 100 mg intravenous, 3 times/day, consecutively for 7 days, n = 12) and control group (equivalent normal saline, n = 14). General clinical data, changes of arterial blood gas, hemodynamics and respiratory mechanics were observed and recorded at admission and at 7 days after treatment. Ventilator-free and shock-free days, ICU stay within 28 days after admission were recorded and 28-day mortality was used as judge prognosis index. RESULTS: CIRCI rate in 45 early ARDS patients was 57.8% (26 patients), and the shock rate was markedly higher in ARDS patients with CIRCI than patients without CIRCI (46.2% vs 5/19). There were no significant differences in baseline parameters, oxygenation and illness severity between the treatment and control groups, except for markedly lower lactic level in the treatment group [2.7(1.2, 3.9) mmol/L vs 4.6(2.5, 6.3) mmol/L, P < 0.05]. After 7 days of treatment, PaO2/FiO2 markedly increased, while heart rate obviously decreased in the both groups. Compared with the control group, survival time of patients was significantly longer and shock rate of the patients was markedly lower in treatment group within 28 days (5/12 vs 10/14, P < 0.05). The 28-day mortality, which were adjusted by baseline arterial lactic, was lower in the treatment group (2.6/12) than in the control group (5.8/14) while with no significant difference (P > 0.05). There was no significant difference in complication incidence between the two groups. CONCLUSION: Stress dose glucocorticoid could reduce shock incidence and prolong survival time, and has a tendency of lower 28-day mortality in early ARDS patients combined with CIRCI.

[The evaluation value of severity and prognosis of septic shock patients based on the arterial-to-venous carbon dioxide difference].

OBJECTIVE: To assess the value of central venous-to-arterial carbon dioxide difference [P((cv-a))CO2] in evaluation of disease severity and prognosis in patients with septic shock. METHODS: There were 45 consecutive resuscitated septic shock patients from April 2009 to October 2010 included immediately after their admission into our ICU. The patients were divided into low P((cv-a))CO2 group and high P((cv-a))CO2 group according to a threshold of 6 mm Hg (1 mm Hg = 0.133 kPa). All patients were treated by early goal directed therapy (EGDT). The parameters of hemodynamics, lactate clearance rate, the Acute Physiology and Chronic Health Evaluation II (APACHE II) score, the sequential organ failure assessment (SOFA) score, 6 h rate of EGDT achievement, the ICU mortality and 28 days in-hospital mortality were recorded for all patients. RESULTS: There were 30 patients in the low P((cv-a))CO2 group, and 15 in the high P((cv-a))CO2 group. There were no significant differences between low P((cv-a))CO2 and high P((cv-a))CO2 patients in age, APACHE II score and SOFA score (all P > 0.05). Compared with the high P((cv-a))CO2 group, the low P((cv-a))CO2 group had higher cardiac index (CI) and 24 h CI, higher delivery O2 (DO2) and 24 h DO2, higher central venous oxygen saturation (ScvO2) [(74 ± 9)% vs (67 ± 8)%], lower lactate [(3.4 ± 2.1) mmol/L vs (5.7 ± 4.5) mmol/L] and higher ΔSOFA score [(0.7 ± 1.8) vs (-0.4 ± 1.1)], lower 24 h SOFA score [(7.8 ± 2.0) vs (9.8 ± 2.0)], higher 6 h rate of EGDT achievement (83.3% vs 53.3%) (P < 0.05), however, there were no differences in 28 days mortality and ICU mortality between the two groups (P > 0.05). CONCLUSION: P((cv-a))CO2 might be an indicator for predicting the severity of patients with septic shock and evaluating tissue perfusion.

[Assessment of central venous-to-arterial CO(2) difference during early goal-directed therapy in patients with septic shock].

OBJECTIVE: To detect the changes of central venous-to-arterial carbon dioxide difference (P(cv-a)CO(2)) during early goal-directed therapy (EGDT) in patients with septic shock and evaluate its' value in predicting adequate resuscitation and prognosis. METHODS: From April 2009 to October 2010, 26 septic shock patients were enrolled in the study. EGDT was performed in all the patients immediately after enrollment. According to the whether they achieved early goal with in the 6 hour or not, patients were separated to EGDT achievement and un-achievement groups. At the onset and after the 6 hours EGDT, mean arterial pressure (MAP), cardiac index (CI), central venous oxygen saturation (ScvO(2)), oxygen delivery (DO(2)), oxygen consumption (VO(2)), oxygen extraction ratio (O(2) ext), lactate, P(cv-a)CO(2) were recorded. The Acute Physiology and Chronic Health Evaluation II (APACHE II) score and 28 day mortality were compared between 2 groups. RESULTS: There were no significant difference of age and sex between the 15 patients who achieved early goals and 11 patients who did not. EGDT un-achievement patients had higher APACHE II score (21 ± 5) and 28 day mortality (9/11) when compared with EGDT achievement patients (t = 2.985, χ(2) = 4.547, P < 0.05). In EGDT un-achievement group, MAP, CI, DO(2), VO(2), O(2)ext, ScvO(2), Lac, P(cv-a)CO(2) were comparable between the onset and 6 hours after EGDT. However, in EGDT achievement group, MAP ((90 ± 9) mmHg (1 mmHg = 0.133 kPa)), CI ((4.0 ± 1.8) L×min(-1)×m(-2)), DO(2) ((596 ± 274) ml×min(-1)×m(-2)), ScvO(2) (76.9% ± 4.1%) increased, and P(cv-a)CO(2) ((4.2 ± 2.7) mmHg) decreased significantly after 6 hours of EGDT (t values were -3.393, -2.985, -2.103 and -3.195 respectively, all P < 0.05). The changes of P(cv-a)CO(2) between the onset and 6 hours after EGDT, demonstrated high value for predictability of outcome, according to the area under the ROC curve (AUC) was 0.839 (P = 0.004). As a predictor for death, increasing of P(cv-a)CO(2) after 6 hours of EGDT has a sensibility of 100% and specificity of 60%. CONCLUSIONS: Increasing of P(cv-a)CO(2) after EGDT purports inadequate tissue perfusion in patients with septic shock. Changes of P(cv-a)CO(2) during EGDT demonstrated a useful tool to evaluate adequate resuscitation and prognosis.

[The clinical application of pulmonary vascular permeability index on differential diagnosis of acute pulmonary edema].

OBJECTIVE: To assess the value of pulmonary vascular permeability index in differentiating acute lung injury (ALI) from cardiac pulmonary edema. METHODS: Critically ill patients with acute pulmonary edema were included from May, 2004 to September, 2008. Patients were divided into two groups, the ALI group and the cardiac pulmonary edema group (C group). Pulmonary vascular permeability index (PVPI), intrathoracic blood volume (ITBVI) were determined by pulse indicator continuous cardiac output (PiCCO) system. RESULTS: (1) Thirty-four patients were enrolled, 22 cases in ALI group and 12 cases in C group. (2) The PVPI in patients of ALI group (2.7 ± 1.4) was higher than that of C group (1.9 ± 0.6; P < 0.05). EVLWI and ITBVI did not have the significant difference between the two groups (P > 0.05). (3) PVPI was positively correlated with EVLWI (r = 0.762), negatively correlated with PaO2/FiO2 (r = -0.478). (4) ARDS was diagnosed in 13 cases, including 8 pulmonary cause (ARDSp) and 5 extra-pulmonary cause (ARDSexp). PVPI, EVLW/ITBV and EVLWI of patients with ARDSexp were obviously higher than those with ARDSp. CONCLUSIONS: PVPI may be useful for differentiating the types of pulmonary edema in the critically ill.

[Effect of conservative fluid management strategy on the outcomes in patients with acute lung injury: a meta-analysis].

OBJECTIVE: To evaluate the effect of conservative fluid management on the outcomes in patients with acute lung injury (ALI). METHODS: Randomized controlled trials (RCTs) and cohort trials on conservative fluid management from January 1, 1990 to May 20, 2010 were retrieved by electronic and manual searching. A meta-analysis of effect of conservative fluid management on the outcomes in ALI patients was conducted by the methods as recommended by the Cochrane Collaboration. RESULTS: Four RCTs involving 594 cases in conservative fluid management group and 584 in conventional fluid management group were included into the Meta-analysis. Compared with the conventional fluid management group, there was no beneficial effect of conservative fluid management strategy on mortality in ALI patients (P = 0.16). However, the duration of mechanical ventilation was shortened while the incidence of renal failure remained unchanged. Three retrospective cohort trials involving 296 cases in conservative fluid management group and 750 in conventional fluid management group were included into the meta-analysis. As compared with the conventional fluid management strategy, conservative fluid management strategy had improved the patient outcomes (P < 0.001). CONCLUSION: No beneficial effect of conservative fluid management strategy on the mortality is observed in the ALI patients. And the ventilator-free durations become elongated. However, further trials of a larger sample size and a higher quality are warranted.

[Passive leg raising predicts volume responsiveness in patients with septic shock].

OBJECTIVE: To evaluate the hemodynamic response to passive leg raising (PLR) indicates fluid responsiveness in patients with septic shock. METHODS: Twenty patients with septic shock, considered for fluid challenge (FC), were enrolled in the study from June 2009 to May 2010. Hemodynamic changes were determined by pulse-contour derived cardiac index at baseline, before and after PLR, return to baseline for 10 min, before and after fluid challenge (250 ml saline for 10 min). An increase of SV after fluid challenge (FC-ΔSV) ≥ 10% were defined responders. RESULTS: Twenty patients with septic shock were included in the study. PLR and fluid challenge were performed 46 instances, among which 15 instances were defined as response group. SV and pulse pressure induced by PLR (PLR-ΔSV and PLR-ΔPP) were increased significantly in response group [(76 ± 19) ml vs. (65 ± 18) ml, (73 ± 20) mmHg vs. (62 ± 20) mmHg (1 mmHg = 0.133 kPa), P < 0.05], while in nonresponse group there were no significant change. PLR-ΔSV and PLR-ΔPP were correlated with FC-ΔSV (r = 0.51, P = 0.001; r = 0.45, P = 0.006), central venous pressure (CVP) were unrelated with FC-ΔSV. Area under curve (AUC) for PLR-ΔSV, PLR-ΔPP and stroke volume variation (SVV) were 0.846, 0.791 and 0.708. PLR-ΔSV ≥ 12.5% predicted fluid responsiveness with sensitivity of 80% and specificity of 93.5%. PLR-ΔPP ≥ 9.5% predicted fluid responsiveness with sensitivity of 73.3% and specificity of 83.9%. CONCLUSIONS: PLR-ΔSV and PLR-ΔPP can predict fluid responsiveness in patients with septic shock. PLR-ΔSV and PLR-ΔPP have a greater ability in predicting volume responsiveness than CVP and SVV.

[Effects of different reference point on intra-abdominal pressure measurement in critically ill patients: a clinical trial].

OBJECTIVE: To investigate the effects of different reference point on intra-abdominal pressure (IAP) measurement. METHODS: Nine critically ill patients with risk of intra-abdominal hypertension (IAH) were studied from July 2008 to June 2010, all of the patients were equipped with abdominal cavity drain and urinary drainage tube. By which IAP was measured using direct and indirect methods respectively. The symphysis pubis, phlebostatic axis and the midaxillary line at the level of the iliac crest were defined as reference points. According to the different reference point, three sets of IAP measurements were obtained in the supine position with each method and kept as IAP(S), IAP(P), IAP(I). Bland-Altman method analysis and Pearson's correlation were performed to evaluate the relationships between results from different reference points with direct and indirect methods. Paired t-test was performed to evaluate the differences among different reference points. RESULTS: Sixty measurements of IAP(S), IAP(P) and IAP(I) were obtained. In direct measurement through abdominal cavity drain, IAP(I) (13.8 ± 3.9) mmHg (1 mmHg = 0.133 kPa) was significantly higher than IAP(P) (12.8 ± 3.6) mmHg and IAP(S) (9.1 ± 3.6) mmHg, P < 0.05; while in indirect measurement through urinary drainage tube, IAP(I) (12.7 ± 3.2) mmHg was significantly higher than IAP(P) (11.7 ± 2.9) mmHg and IAP(S) (7.9 ± 3.0) mmHg too, P < 0.05. In either direct or indirect method, IAP(P) was higher than IAP(S), P < 0.05. And good correlations were found among IAP(S), IAP(P) and IAP(I). CONCLUSIONS: In the supine position, pressure obtained via the bladder could reflect authentic IAP. But selection of reference point has great impact on IAP measurement.

[Prospective research on the prognosis of septic shock based on the change of lactate concentration in arterial blood].

OBJECTIVE: To evaluate the correlation between the lactate in artery blood and lactate clearance rate and prognosis in patients with septic shock in intensive care unit (ICU). METHODS: Prospectively studied 221 consecutive patients with septic shock from December 2005 to December 2007, the diagnosis of septic shock was made based on the criteria of 2001 ACCP/SCCM. For inclusion in the study, we required admission of the patients within 24 h of septic shock diagnosed. The criteria for exclusion from the study were an age of less than 18 years, pregnancy, serious inadequacy of liver and renal, needing blood purification, or acidosis result of biguanides drugs, or do-not-resuscitate. The eligible patients assigned to early goal-directed therapy. The 6-, 24- and 72-hour lactate clearance rate were calculated, the relationship between the level of lactate, lactate clearance rate, the APACHE II score, the number of failed organ and the 28-day mortality were evaluated. RESULTS: One hundred and five patients with septic shock were admitted, 74 male and 31 female, the mean age was 70 +/- 12 years. The 28-day mortality was 54.3%. The average APACHE II score at baseline was 20 +/- 8, the number of failed organs was 3.0 +/- 1.1 and the average concentration of lactate in artery blood at baseline was (3.8 +/- 3.6) mmol/L. Significant differences of the lactate at 0-, 6-, 24- and 72-hour were found between death group and survival group. There were 69 patients whose lactate in artery blood at baseline was > 2 mmol/L, 24 survived. The lactate clearance rate of 6- and 24-hour in survival group were significantly higher than death group (P < 0.01, P < 0.05, respectively), but the lactate clearance rate of 72-hour was not (P > 0.05). By using a multivariate logistic regression analysis, it showed that the lactate clearance rate of 6-hour was the independent predictive factor of survival. The area under the receiver operating characteristic curve (ROC) was 0.564, 0.649, 0.754, 0.784, respectively according to the level of the lactate at 0-, 6-, 24-hour and the 6-hour lactate clearance rate. The cutoff of 6-hour lactate clearance rate was >or= 30.0%, resulting in a sensitivity of 60.0% and a specificity of 77.3%. CONCLUSIONS: Dynamic observation of lactate level is very important for the survival in the patients with septic shock. Patients with elevated lactate and not decreased rapidly have a worse outcome. The 6-hour lactate clearance rate might be the indicator for predicting the prognosis of patients with septic shock.

[Effect of lung stress index upon titration of positive end-expiratory pressure at post-recruitment in patients with acute respiratory distress syndrome].

OBJECTIVE: To investigate the relationship of stress index and positive end-expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS) and to determine the relationship of stress index, lung recruitment, oxygenation and respiration mechanics. METHODS: Fourteen ARDS patients were enrolled. During volume control ventilation with constant inspiratory flow, the pressure-time (P-t) curve was fitted to a power equation: P = a x time(b) + c, where coefficient b (stress index) describes the shape of curve: b = 1, straight curve; b < 1, progressive increase in slope; and b > 1, progressive decrease in slope. Positive end-expiratory pressure (PEEP) was set to obtain b value between 0.9 and 1.1 after application of a recruiting maneuver (RM). PEEP was changed to obtain 0.6 < b < 0.8 and 1.1 < b < 1.3. The sequence of experimental conditions was random. Recruited volume (RV) was measured by static pressure-volume curve method. Hemodynamics, pulmonary mechanics and gas exchange were observed simultaneously. RESULTS: PEEP at b < 1, b = 1 and b > 1 were (8.3 +/- 1.5) cm H2O, (15.0 +/- 1.9) cm H2O and (18.4 +/- 1.9) cm H2O respectively with a significant difference (P < 0.001). At b = 1 and b > 1, the partial arterial oxygen tension (PaO2/FiO2) [(350 +/- 113) mm Hg, (338 +/- 124 mm Hg)] were higher than that [165 +/- 60) mm Hg] of pre-RM (P < 0.05). the plateau pressure (Pplat) at b = 1 [(29 +/- 4) cm H2O] and b > 1 [(33 +/- 7) cm H2O] post-RM were significantly higher than that at b < 1 [(22 +/- 4) cm H2O] (P < 0.05); the Pplat at b > 1 was higher than that [(25 +/- 16) cm H2O] pre-RM (P < 0.05). Compared with the static pulmonary compliance (Cst) at b = 1 [(39 +/- 11) ml/cm H2O], Cst at b > 1 [(26 +/- 7) ml/cm H2O] decreased significantly (P < 0.05). The RV at b = 1 and b > 1 [(402 +/- 204) ml, (588 +/- 269) ml] were significantly higher than that at pre-RM and b < 1 [(136 +/- 111) ml, (175 +/- 122) ml] (P < 0.05). At pre-RM, b < 1, b = 1 and b > 1, HR, mean arterial pressure (MAP) and lactate showed no significant difference (P > 0.05). CONCLUSION: Stress index at post-RM can be an excellent method of PEEP titration for ARDS patients.

[Effect of continuous aspiration of subglottic secretions on the prevention of ventilator-associated pneumonia in mechanically ventilated patients: a prospective, randomized, controlled clinical trial].

OBJECTIVE: To evaluate the effect of continuous aspiration of subglottic secretions (CASS) on the prevention of ventilator-associated pneumonia (VAP) in mechanically ventilated patients. METHODS: Patients ventilated mechanically at the ICU from October, 2004 to April, 2006 were randomly divided into 2 groups: one group received CASS and the other did not (NASS group). CASS was performed immediately after admission for patients in the CASS group. The diagnosis of VAP was made based on clinical presentations, and the evaluation of VAP was done using simplified version of the clinical pulmonary infection score (CPIS). The general status of the patients, days of ventilated treatment, the volume of daily aspirated subglottic secretions, the morbidity and timing of VAP, days of stay in ICU and mortality within 28 days of hospitalization were recorded. RESULTS: One hundred and one patients were included in the study. There were 48 patients in the CASS group who were treated with mechanical ventilation more than 48 hours, and 43 patients in the NASS group. There was no significant difference in the general status of the patients and days of ventilation between 2 groups with the averaged score of APACHE II being 20.8 +/- 6.1. The average of CPIS was of 5.6 +/- 1.0 when VAP was diagnosed. The mean volume of aspirated subglottic secretions within the first 24 hours in the CASS group (n = 48) was (27.2 +/- 21.2) ml. The morbidity of VAP in the CASS and the NASS groups was 25.0% and 46.5% respectively (P = 0.032), and the length of time before the onset of VAP in these 2 groups was (7.3 +/- 4.2) days and (5.1 +/- 3.0) days respectively (P = 0.100). There was a significant increase in the percentage of gram-positive cocci from the lower respiratory tracts in the NASS group compared with that in the CASS group (P = 0.004). In the CASS group, the volume of the first daily aspirated subglottic secretions in patients with VAP was significantly less than that in patients without VAP (P = 0.006). The morbidity of VAP in patients with failed early aspiration (the volume of first daily aspirated secretions < or = 20 ml) was significantly higher than that in patients in whom the aspiration was effective (P < 0.01). The length of mechanical ventilation in patients with VAP was significantly longer than that in patients without VAP (P = 0.000). The in-hospital mortality in patients with VAP was significantly higher than that in patients without VAP (P = 0.009), and the mortality in 28 days after admission in patients with VAP was significantly higher than that in patients without VAP (P = 0.035). CONCLUSION: Effective continuous aspiration of subglottic secretions could significantly reduce the morbidity of early-onset VAP.

[The prognostic value of extravascular lung water index in critically ill septic shock patients].

OBJECTIVE: To investigate the prognostic value of extravascular lung water index (EVLWI) in critically ill patients with septic shock in intensive care unit (ICU). METHODS: EVLWI was determined by using a PiCCO Monitor, and the daily fluid balance was recorded. RESULTS: Fifty patients with septic shock were admitted and twenty-six patients survived. The average EVLWI at baseline was 11.7 ml/kg, and the difference was not different between survivors and nonsurvivors, P = 0.551. The EVLWI of day 3 (EVLWI(d3)) in nonsurvivors was significantly higher than the survivors [(14.3 +/- 8.8) ml/kg vs (8.1 +/- 2.7) ml/kg, P = 0.001]. If the patients were divided into three groups by the EVLWI(d3), group one 0-7 ml/kg (4/16), group two 8-14 ml/kg (10/24), and group three > 14 ml/kg (10/10), the hospital mortality of the third group was significantly higher than the other two groups (P = 0.000, 0.002). There was a significant difference between the survivors and the nonsurvivors in the fluid balance at the first day and the following three days (P = 0.000, 0.000). Negative fluid balance was associated with a lower mortality. By using receiver operating characteristic analysis, the area under the curve was 0.740 +/- 0.072 to EVLWI(d3). If EVLWI > 7.5 ml/kg, the sensitivity and the specificity of accurate judgment were 83.3% and 53.8%. CONCLUSION: Dynamic observation of EVLWI can be one of the factors for predicting the prognosis of patients with septic shock. A reduction of EVLWI at early treatment and a negative fluid balance were associated with a better prognosis.