Objective  To explore the association between systolic blood pressure variability and in-hospital mortality in patients with sepsis. Methods  This study was a prospective, multicenter, and cohort study. Data were derived from the China Critical Care Sepsis Trial, which was conducted from January 2013 to August 2014. Patients aged ≥18 years with length of stay of intensive care unit （ICU）more than 24 h were included. The patients who were diagnosed  as sepsis for more than 48 h and lack of blood pressure for 2 h or longer were excluded. Systolic blood pressure, diastolic blood pressure, fluid intake and output were collected. The systolic blood pressure coefficient of variation (SBP_cv) was calculated and divided into four groups (Q₁, Q₂, Q₃, Q₄) according to the interquartile of SBP_cv. The multivariable Logistic regression was applied to explore the association between systolic blood pressure variability and in-hospital mortality. Results  A total of  1 356 patients with sepsis were included, with 929 (68.5%) males and 427 (31.5%) females, median age 67.0 years (52.0, 78.0).Among them,  483 (35.6%) patients died during hospitalization. After adjusting for potential confounding factors, for every 10% of SBP_cv increasing, the risk of in-hospital mortality increased 43% (OR=1.43, 95%CI:1.11-1.98). Compared with Q1 group, patients in Q4 group had a 69% increased risk of in-hospital mortality (OR=1.69, 95%CI:1.31-2.25) and a 23% increased risk of 28 d mortality (OR=1.23, 95%CI:1.07-1.84). Conclusion  Higher systolic blood pressure variability was correlated with higher risks of in-hospital mortality and 28 d mortality.

Objective  To investigate the impact of Candida albicans colonization on the mortality, duration of antibiotic therapy, immune and inflammation status in patients with ventilator-associated pneumonia (VAP) caused by multidrug-resistant Pseudomonas aeruginosa. Methods  This prospective multicenter cohort study included patients with VAP caused by multidrug-resistant Pseudomonas aeruginosa (MDR-Pa) admitted to six tertiary teaching hospitals from June 2018 to June 2023. The patients were divided into colonization group and non-colonization group based on the presence of Candida albicans detected in the broncho-alveolar lavage fluid (BALF). The 30-d all-cause mortality, duration of antibiotic therapy, immune and inflammation status were compared between the two groups after VAP diagnosis on the day1, day3, day5, and day7. Results  During the five-year research period, a total of 232 VAP patients caused by MDR-Pa were included from six participating units in the intensive care unit (ICU), with 105 cases in the colonization group and 127 cases in the non-colonization group. The Pseudomonas aeruginosa detected in BALF samples from the non-colonization group showed higher sensitivity to aminoglycosides, cephalosporins, and carbapenems compared to the colonization group (P<0.05). However, both groups showed lower sensitivity to 16 antibiotics compared to China antimicrobial surveillance network (CHINET) 2022 (P<0.05).  Interleukin-17A and (1,3)-β-D glucan levels in the non-colonization group were consistently lower than those in the colonization group at various time points, and other inflammatory markers were more likely to return to normal values (P<0.05). Additionally, the absolute values of T and Th lymphocytes in the non-colonization group recovered to normal levels faster on the day 7 (P<0.05). There was no statistically significant difference in the 30-d all-cause mortality between the two groups (25.7% vs 22.8%, P=0.61), but the non-colonization group had a significantly shorter duration of antibiotic therapy compared to the colonization group ［(11.3±3.1)d vs （14.2±4.7)d, P<0.01］, with a trend towards shorter ICU hospitalization time. Conclusion  The colonization of Candida albicans in the airway does not affect the 30-d all-cause mortality of patients with VAP caused by MDR-Pa. However, it does prolong the inflammatory response and the duration of antibiotic use, as well as delay the recovery of immune function.

Objective  To explore the correlation of simple measurement of inspiratory muscle pressure index from the ventilator (PMIvent) and reference measurement of inspiratory muscle pressure index on experimental condition (PMIref), the relationship between PMIvent and inspiratory effort, and further to determine the clinical feasibility and validity of PMI for assessing inspiratory effort during pressure support ventilation (PSV).  Methods  Adult acute respiratory failure patients undergoing mechanical ventilation were screened daily and enrolled 24 h after switching to PSV mode. Baseline ventilators were set according to the principle of keeping tidal volume/ predicted body weight(VT/PBW) at 6-8 mL/kg and respiratory rate (RR) at 20-30 breaths/min and the decision of the responsible ICU physician. A downward support pressure ( PS )titration was conducted from 20 cmH₂O to 2 cmH₂O. Three end-inspiratory holdings (EIO) and three end-expiratory holdings (EEO) were performed. PMIvent was calculated as the difference between plateau pressure (Pplat) within 2 s after EIO and the airway peak pressure (Ppeak) at EIO. PMIref was calculated as the difference between Pplat at one cardiac cycle after EIO and Ppeak at EIO. Flow, airway pressure (Paw), and esophageal pressure (Pes) signals were displayed continuously and saved. PMIref, PMIvent and esophageal pressure time product per breath (PTPes) were measured. PTPes per minute was calculated as the product of PTPes and RR. The “normal” range of PTPes per minute was defined as 50 to 200 cmH2O·s·min-1. The accuracy of PMIvent compared to PMIref was assessed with a Bland-Altman plot. The correlation between PMI and inspiratory effort was evaluated as the coefficient of determination (R²). The ability of PMI to detect high/low effort was assessed using the area under the receiver operating characteristics curve (ROC AUC). The optimal cut-off values were selected based on the Youden index. Results  The accuracy and precision of PMIvent compared to PMIref showed a low bias (0.18) with smaller 95% limits of agreements (-0.44,0.80). PMIref was significantly related to the PTPes per minute (between-patients R²=0.61, within-patients R²=0.80, respectively). PMIvent was also related to the PTPes per minute (between-patients R²=0.62, within-patients R²=0.81). For a cut-off PTPes<50 cmH₂O·s·min^-1, PMIvent showed an ROC AUC of 0.93 ［0.89,0.96］, and the best threshold was -0.77 cmH₂O. Conclusion  PMIvent can effectively replace PMIref. Like PMIref, PMIvent was significantly related to inspiratory effort and had the potential value to predict low inspiratory effort. 

Objective  To evaluate the influence of vagus nerve stimulation on renal function in septic rats and explore its mechanism. Methods  Forty male SD rats were divided into four groups：sham group, sepsis group, vagus nerve stimulation（VNS）group, and alpha7 nicotinic acetylcholine receptors（α7nAChR）antagonist group（n=10）. Rats in sham injury group only underwent laparotomy to expose the cecum, and then the cecum was returned to the abdominal cavity. Sepsis rat model was constructed by cecal ligation and perforation（CLP）. Rats in VNS group were given electrical stimulation on left cervical vagus nerve for 20 min after CLP. Rats in α7nAChR antagonist group were intraperitoneally injected with 2 mg/kg methyllycaconitine（MLA） at 30 min before CLP. At 24 h after CLP, serum of rats was collected to detect levels of blood urea nitrogen（BUN）, serum creatinine（Scr）, tumor necrosis factor-α（TNF-α）and interleukin-6（IL-6）by biochemical and enzyme-linked immunosorbent assay（ELISA）. The 24 h urine volume of each rat was collected, and the 24 h urine volume per kilogram body weight of each rat was calculated. Urinary neutrophil gelatinase-associated lipocalin（NGAL）and kidney injury molecule-1（KIM-1）were analyzed by ELISA. hematoxylin-eosin (HE) staining and TdT-mediated dUTP nick-end labeling (TUNEL) staining were performed to evaluate renal histopathological changes and tubule cell apoptosis. Results  ① The levels of BUN, Scr, TNF-α and IL-6 of rats in sepsis group were significantly higher than those in sham group and VNS group（P<0.01）. ② The 24 h urine volume per kilogram body weight of rats in sepsis group was significantly lower than that in sham group and VNS group （P<0.01）. ③ The levels of urinary NGAL and KIM-1 in sepsis group were significantly higher than those in sham group and VNS group（P<0.01）. ④ As compared with those of rats in sham group and VNS group, the renal histological damage score and the renal tubule apoptotic cell coun of rats in sepsis group were significantly increased（P<0.01）. ⑤ Scr, BUN, TNF-α, IL-6, urinary NGAL, urinary KIM-1, 24 h urine volume per kilogram, renal histological damage score, and renal tubule cell apoptosis count in sepsis group showed no significant difference from α7nAChR antagonist group（P>0.05）. Conclusion  Electrical stimulation of vagus nerve can significantly alleviate sepsis-induced acute kidney injury in rats，through the activation of α7nAChR dependent cholinergic anti-inflammatory pathway.

Objective  To evaluate the correlation between optic nerve sheath diameter (ONSD) and intracranial pressure (ICP) in patients with aneurysmal subarachnoid hemorrhage (aSAH). Methods  All patients were diagnosed with aSAH and received microsurgery clipping at the Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University from December 1, 2019 to June 1, 2022. The patients received head computed tomography (CT) and subdural ICP monitoring devices were kept to monitor the ICP. The ONSD were measured with CT and ICP was recorded. The agreement among the three observers was evaluated with intraclass correlation coefficient (ICC), and the regression of ONSD and ICP was evaluated with Spearman's correlation coefficient. Results  A total of 184 patients were included, with 282 data of ONSD and ICP recorded. The median ICP was 12 (9, 18) mmHg (1 mmHg=0.133 kPa)， and the median ONSD was 5.59 (5.26, 5.99) mm. The ICC of left and right ONSD measured by three observers was 0.895 (0.872-0.915, P<0.001) and 0.869 (0.841-0.894, P<0.001), respectively. There was a significant positive correlation between ONSD and ICP (r=0.273，95% CI: 0.158-0.381, P<0.001). The area under the receiver operating characteristics curve of ONSD to predict ICP>22 mmHg was 0.753 (95% CI: 0.670-0.836, P<0.001), The cutoff point was 5.61 mm, with 85.2% sensitivity and 55.3% specificity. Conclusion  Measurement of ONSD by CT is repeatable, and it significantly correlates by ICP.