Objectives: Sepsis is one of the most common comorbidities in severe community-acquired pneumonia (SCAP) patients. We aimed to investigate the characteristics and mortality risk factors of SCAP patients hospitalized with Sepsis.

Design: A retrospective, single-centre study.

Setting: This study was conducted at a tertiary hospital in Southern China.

Participants: A total of 119 patients with SCAP, aged 17 years or older, were treated in the Integrated intensive care unit from 1 January 2018 to 30 December 2020.

Interventions: none.

Outcome: 180-day mortality was the primary outcome.

Results: 119 patients were divided into the survivors (83 patients,69.75%), and the non-survivors (36 patients,30.25%). There are more pronounced inflammatory responses and respiratory problems at the beginning of the disease in non-survivors, requiring stronger respiratory and circulatory support. The CURB-65 score was a better predictor of mortality than the PSI and APACHE2 scores, AUCs of CURB-65: OR 0.744, p<0.005. For the entire treatment cycle, the non-survivors had a longer duration of persistent fever, required continuous and repeated airway intervention, and a longer duration of Vasopressor support (P<0.001). SCAP with bacterial infection as the onset, or secondary bacterial infection had a poor prognosis (P=0.018). The non-survivors had more use of different types of antimicrobials (P<0.05), because of Multidrug-resistant (MDR) organisms. And have faced more antifungal treatment failures (P=0.006). The mortality risk factors were comorbid with a duration of Vasopressors support, duration of persistent fever, age, numbers of antimicrobials for MDR organisms, CURB-65 score and duration of Neuromuscular Blocking Agents (NMBAs) (OR=1.234, OR=1.158, OR=1.084, OR=6.484, OR=3.386, OR=1.505, p<0.005, respectively).

Conclusion: Dynamic monitoring of the duration of patients' abnormal indicators can help predict the prognosis. Age≥65.5 years, fever duration ≥9.5 days, number of antimicrobials for MDR organisms ≥2 types, longer NMBAs and Vasopressors use, and higher CURB-65 score were mortality risk factors in SCAP-Sepsis patients.

Study design

This was a single-centre retrospective analysis. Patients with the onset of CAP and conforming to Sepsis (infection +SOFA≥2) were included in the analysis,[8] with the outcome conforming to severe pneumonia. [11-12] The primary outcome was 180-day mortality. The baseline characteristics, clinical outcomes, and prognostic factors related to mortality were assessed. The written informed consent was waived due to the observational nature of the study. Ensure patients’ anonymity.

Subjects

We retrospectively analyzed the clinical data of 119 patients with SCAP who were treated in the Integrated ICU of The First Affiliated Hospital of Soochow University (a comprehensive tertiary adult hospital) from 1 January 2018 to 30 December 2020. The observation endpoint was 180-day mortality. Our inclusion criteria were: CAP whose outcome met the diagnosis of severe pneumonia and patients who met Sepsis criteria (SOFA≥2) at the onset. Our exclusion criteria were: patients Under 17 years of age. Patients who refused invasive resuscitation. Patients who have incomplete data. Patients whose outcome of treatment is not clear. Patients with unknown or mixed infection (more than one known infection source). Patients with Long-term Sanatoriums and Tend and Protect Hospitals treatment experience. Patients with transplantation, primary lung tumor, or advanced tumors at other sites. Presence of leukopenia or neutropenia (unless due to pneumonia). Adjuvant therapy for severe immunosuppression in human immunodeficiency virus-positive (HIV) patients (CD4 <100). Patients with previous underlying pulmonary diseases (e.g., COPD, asthma, etc.) require long-term home oxygen therapy. Figure 1 shows the flow diagram of the study.

Data collection and definition

Our study used an electronic medical record system to collect data for retrospective analysis. Our data were recorded by attending nurses and doctors at the time of patients’ presentation to the emergency department (ED). The demographic characteristics of each patient including comorbidities were reviewed thoroughly. We collected the patients' worst vital signs, laboratory results, ventilator support, and use of pressors within 24 hours of admission before initiation of ICU treatment. Score scales were used to calculate the relevant parameters of patients at admission, including APACHE2, SOFA, Pneumonia Severity Index (PSI), and CURB-65(a 5-point score based on confusion, urea, respiratory rate, blood pressure, and age ≥65). [13-16] (table2) Duration of fever, infection markers, respiratory management, and Sepsis medication were recorded during ICU treatment. Pathogenic microorganisms and subsequent antibiotic use of CAP were also collected.