With the rapid advancement of hemodynamic indices and monitoring technologies, their classification methods and application processes have become increasingly complex. Currently, no unified standard hasbeen established, making it difficult to fully meet the clinical requirements for hemodynamic management. To assist in hemodynamic monitoring assessment and therapeutic decision-making in critically ill patients, the Critical Hemodynamic Therapy Collaborative Group, in conjunction with the Critical Ultrasound Study Group, has jointly developed the Standard for the Application of Hemodynamic Monitoring Techniques in Critical Care. The first part of this standard systematically categorizes hemodynamic indicators into flow indicators, pressure and its derivative indicators, and tissue perfusion indicators, while elaborating on the clinical application of each. The second part establishes a standardized clinical implementation pathway for hemodynamic monitoring. It proposes a tiered monitoring strategy-comprising basic, advanced, indication-specific, and special scenario monitoring-tailored to different clinical settings. It emphasizes the central role of critical care ultrasound across all levels of monitoring and establishes hemodynamic assessment standards for organs such as the brain, kidneys, and gastrointestinal tract. This standard aims to provide a unified framework for clinical practice, teaching, training, and research in critical care medicine, thereby promoting standardized development within the discipline.

Objective:To explore the risk factors and prognosis of sepsis-related cardiomyopathy.Methods:Patients with sepsis and septic shock admitted to the Critical Care Medicine Department at Peking Union Medical College Hospital from October 2017 to February 2021 were enrolled. Echocardiographic parameters including left ventricular ejection fraction (LVEF), tricuspid annular plane systolic excursion (TAPSE) and cardiac index (CI) were obtained within 24 h after admission. Hemodynamic parameters including heart rate, mean arterial pressure and central venous pressure were also collected. The risk factors of 45-day mortality were analyzed using Cox regression analysis. Kaplan-Meier survival analysis was performed to compare 45-day mortality among patients with normal left ventricle (LV) systolic function group, sepsis-related takotsubo cardiomyopathy (ST) and septic cardiomyopathy (SC) group as well as between patients with normal right ventricular (RV) function and patients with RV dysfunction.Results:According to LV systolic function, patients were categorized into three groups: normal group [174 (66.9%)], SC group [66 (25.4%)] and ST group [66 (25.4%)]. In comparison with those in normal group, patients in SC group and ST group had higher acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score and sequential organ failure assessment (SOFA) score ( P<0.05). No difference was found between SC group and ST group regarding APACHE Ⅱ score and SOFA score( P>0.05). ST group had lower LVEF [33(28, 41)% vs. 45(38, 48)%, P<0.05], CI [2.29 (1.99, 2.53)L·min -1·m -2 vs. 3.04(2.61, 3.61) L·min -1·m -2, P<0.05] higher TAPSE [18.6(16.0, 21.2)mm vs. 15.1(12.5, 19.0)mm, P<0.05] than SC group. A Cox regression survival analysis showed that right ventricular dysfunction (RVD) was an independent predictor of 45-day mortality ( HR=1.992, 95% CI 1.088-3.647, P=0.025). A Kaplan-Meier analysis revealed no significant difference regarding 45-day mortality among ST group [25.0%(5/20)], SC group [30.3%(20/66)] and normal group 18.4%(32/174)( P=0.158). RVD patients [38.0%(30/79)] had significantly higher 45-day mortality than patients with normal RV function [14.9%(27/181), P<0.001]. Conclusions:In comparison with SC patients, ST patients tend to have worse LV systolic function, lower cardiac output and better RV function. However, neither ST nor SC is associated with 45-day mortality. RVD is a risk predictor of 45-day mortality, which should be monitored in septic patients.

Objective:To explore the relationship between the pulse pressure/central venous pressure (PP/CVP) ratio and the cardiac output (CO) of patients after cardiac surgery from the basic principles of hemodynamics, and to further evaluate the predictive value of PP/CVP ratio in patients with secondary low cardiac output syndrome (LCOS) after cardiac surgery.Methods:A retrospective study was conducted, and patients who received pulse indicator continuous cardiac output (PiCCO) monitoring were enrolled at the department of critical care medicine of Peking Union Medical College Hospital from January 1, 2016, to September 1, 2021. Patients were divided into two groups: the LCOS group [cardiac index (CI) < 33.34 mL·s -1·m -2, 25 cases] and the non-LCOS group (CI ≥ 33.34 mL·s -1·m -2, 125 cases) according to the CI at 6 hours after surgery. The general clinical data and hemodynamic parameters were collected. Correlations between PP/CVP ratio and PiCCO monitoring indicators were performed with Pearson or Spearman correlation test. Receiver operator characteristic curve (ROC curve) analysis was carried out to evaluate the predictive value of the parameters in patients with LCOS after cardiac surgery. Results:A total of 150 patients with PiCCO monitoring after cardiac surgery were included. There were no differences in baseline characteristics between the two groups, while PP in the LCOS group was lower than that in the non-LCOS group [mmHg (1 mmHg ≈ 0.133 kPa): 40 (37, 44) vs. 55 (46, 64)], CVP was higher than that in the non-LCOS group [mmHg: 12 (11, 14) vs. 10 (8, 12)], and PP/CVP ratio in the LCOS group was lower than that in the non-LCOS group [3.3 (2.9, 3.7) vs. 5.5 (4.6, 6.8)], with significant differences (all P < 0.05). Correlation analysis results showed that PP/CVP ratio was positively correlated with CI, CO, and stroke volume index (SVI), respectively ( rs = 0.660, 0.592, 0.600, all P < 0.001). CI was negatively correlated with PP ( rs = 0.509, P < 0.001) and positively correlated with CVP ( rs = -0.297, P < 0.001). ROC curve analysis revealed that compared with PP, CVP, SVI and cardiac function index (CFI), PP/CVP ratio was the best predictor of LCOS after cardiac surgery [area under the ROC curve (AUC) was 0.94±0.02, P < 0.001], when the optimum cut-off value was 4.41, the sensitivity was 80.00%, and the specificity was 96.00%. Conclusion:PP/CVP ratio was moderately positively correlated with CO after cardiac surgery, and PP/CVP ratio could be used as a prognostic predictor for LCOS after cardiac surgery.

Objective: To explore the safety and efficacy of dezocine preemptive analgesia in the reconstruction of nasal bone fracture. Methods: From September 2016 to May 2018, 63 patients with simple nasal bone fracture admitted to the 908th Hospital of PLA Joint Logistics Support Force were selected in the study.The patients were divided into two groups by random number table method: dezocine group(n=32) and control group(n=31). The dezocine group was injected with dezocine before surgery, while the control group was injected with 0.9% sodium chloride solution.The differences of MAP, HR, SpO₂ at different time points between the two groups were observed.And the difference of VAS/RSS during operation and 2 hours after surgery were also observed. Results: There were no statistically significant differences in MAP, HR and SpO₂ between the two groups at different time points(10 min before and 10 min after intramuscular injection) (all P>0.05). During operation and 20 min after operation, the MAP values of the control group were (110.1±16.38)mmHg and (105.28±14.81)mmHg, respectively, which were higher than those of the dezocine group [(102.35±14.25)mmHg and (101.25±13.12)mmHg)], the differences were statistically significant(t=2.259, 2.153, all P<0.05). There were no statistically significant difference in HR between the two groups at 10 min before and 10 min after intramuscular injection(all P>0.05). The HR in the control group during operation and at 20min after operation were (90.81±19.52)times/min, (77.25±18.25)times/min, respectively, which were faster than those in the dezocine group [(85.16±17.25)times/min, (71.36±16.15)times/min], the differences were statistically significant(t=2.074, 2.047, all P<0.05). There were no statistically significant differences in SpO₂ between the two groups at different time points(all P>0.05). In the surgery, the RSS score of dezocine group[(4.3±0.6)points] was better than that in control group[(2.1±0.4)points], the difference was statistically significant(t=17.008, P<0.05). The VAS scores in the control group during operation and 20 min after operation were (2.3±0.5)points, (1.5±0.8)points, respectively, , which were lower than those in the control group [(5.5±0.7)points, (2.1±0.6)points](t=20.572, 3.277, all P<0.05). Conclusion Application of dezocine preemptive analgesia in the reconstruction of nasal bone fracture is effective and safe, the hemodynamics is stable and the analgesic effect is definite in the surgery.

In this paper, a new probe is proposed for the dielectric measurement of anisotropic tissue in radio frequency band, which could accomplish the dielectric measurement in perpendicular directions by one operation. The simulative studies are performed in the frequency range from 1-1 000 MHz in order to investigate the influence of probe dimension on the energy coupling and sensitivity of measurement. The suitable probe is designed and validated for the actual measurement in this frequency band. According to the simulation results, the energy coupling of the probe could be kept below -12 dB in the frequency range from 200-400 MHz with high sensitivity of measurement for the dielectric properties of anisotropic tissue. That indicates the new type of probe has the potential to achieve the dielectric measurement of anisotropic tissue in radio frequency band and could avoid the measurement error by multi-operations in the conventional method. This new type of probe could provide a new method for the dielectric measurement of anisotropic tissue in radio frequency band.