[Analysis of epidemiological features and prognostic risk factors in septic shock]

To analyze the epidemiological characteristics of septic shock and identify high risk factors influencing the prognosis based on the eICU Collaborative Research Database.

A retrospective cohort study was conducted. Data of patients with septic shock from 2014 to 2015 in the eICU Collaborative Research Database were collected, including demographic information, general information of intensive care unit (ICU) and hospital, severity scores of illness, comorbidities, primary infection site, vital signs, interventions, serum lactic acid, and outcome measures. Epidemiological characteristics of the septic shock population were analyzed, as well as the ICU mortality, in-hospital mortality, and ICU readmission rate. Multivariate Logistic regression analysis was used to identify independent risk factors for ICU death in patients with septic shock.

A total of 5 564 patients with septic shock were enrolled, comprising 2 903 males and 2 661 females. The age was (66.31±15.84) years (ranged 18-91 years), and body mass index (BMI) was (28.84±9.34) kg/m² (ranged 10.72-121.67 kg/m²). The majority were first admitted to a medical ICU [79.31% (4 413/5 564)], and a higher proportion were hospitals with ≥250 beds [63.93% (3 557/5 564)]. The Sequential Organ Failure Assessment (SOFA) score was 8.51±3.83 (ranged 2-23), Acute Physiology Score III (APS III) was 67.73±29.89 (ranged 7-200), and Acute Physiology And Chronic Health Evaluation IV (APACHE IV) score was 81.57±30.85 (ranged 9-205). Common comorbidities included cardiovascular and cerebrovascular diseases [35.14% (1 955/5 564)], diabetes [31.99% (1 780/5 564)], and liver/kidney diseases [23.89% (1 329/5 564)]. The main primary infection site was pulmonary [34.38% (1 913/5 564)] and urinary tract infections [21.53% (1 198/5 564)]; 14.41% (802/5 564) had two or more concurrent infections. 55.10% (3 066/5 564) received vasopressors, 5.66% (315/5 564) received renal replacement therapy (RRT), and 72.09% (4 011/5 564) received invasive mechanical ventilation. Within the entire eICU population, septic shock patients accounted for 3.310 3% (6 649/200 859) of the total ICU admissions, and accounted for 24.869% (6 649/26 736) of the sepsis patients. The ICU mortality for septic shock patients was 21.30% (1 416/6 649), the in-hospital mortality was 29.39% (1 954/6 649), and the ICU readmission rate was 16.30% (1 084/6 649). Multivariate Logistic regression analysis identified 16 independent risk factors associated with ICU death in patients with septic shock, including female [odds ratio (OR)=1.209, 95% confidence interval (95%CI) was 1.035-1.411, P=0.016], advanced age (OR=1.018, 95%CI was 1.186-1.329, P<0.001), low BMI (OR=0.950, 95%CI was 0.907-0.995, P=0.030), admission in community hospital (OR=1.548,95%CI was 1.321-1.814, P<0.001), higher SOFA score (OR=1.110, 95%CI was 1.081-1.140, P<0.001), higher APSIII score (OR=1.120, 95%CI was 1.085-1.156, P<0.001), comorbidities of chronic obstructive pulmonary disease (OR=1.221, 95%CI was 1.152-1.451, P<0.001), severe liver disease (OR=1.652, 95%CI was 1.226-2.214, P<0.001), or metastatic solid tumor (OR=1.441, 95%CI was 1.184-1.749, P<0.001), pulmonary infection (OR=1.423, 95%CI was 1.210-1.674, P<0.001), increased heart rate (OR=1.082, 95%CI was 1.041-1.126, P<0.001), increased respiratory rate (OR=1.129, 95%CI was 1.067-1.194, P<0.001), decreased systolic blood pressure (OR=0.942, 95%CI was 0.902-0.983, P<0.001), decreased body temperature (OR=0.857, 95%CI was 0.796-0.923, P<0.001), RRT (OR=1.533, 95%CI was 1.117-2.086, P=0.007), and elevated serum lactic acid (OR=1.171, 95%CI was 1.144-1.198, P<0.001).

The ICU mortality for patients with septic shock was 21.30%, in-hospital mortality was 29.39%, and the ICU readmission rate was 16.30%. Female, advanced age, low BMI, admission in community hospital, higher SOFA score, higher APS III score, comorbidities of chronic obstructive pulmonary disease, severe liver disease, or metastatic solid tumor, pulmonary infection, increased heart rate, increased respiratory rate, decreased systolic blood pressure, decreased body temperature, RRT, and elevated serum lactic acid are high risk factors for death in ICU in the patients with septic shock.