Objective:To investigate clinicians' compliance with the 2018 Surviving Sepsis Campaign (SSC) update "1-hour sepsis Bundle therapy" (1-hour Bundle) when treating patients with Sepsis 3 in the intensive care unit (ICU), and to analyze its impact on patient outcomes.Methods:A multicenter, prospective observational cohort study was conducted. A total of 153 ICU patients in Ziyang First People's Hospital, Ziyang People's Hospital and Yanjiang District People's Hospital who were diagnosed of sepsis by the definition and diagnostic criteria of Sepsis 3 from January 2019 to December 2020 were selected. Among them, 95 patients who had completed 1-hour Bundle were divided into the Bundle compliance group. 58 patients who did not complete the Bundle within 1 hours were classified as the Bundle non-compliance group. The distribution of pathogenic bacteria and infected sites, 1-hour Bundle compliance and 28-day survival in the 3 hospitals were analyzed. Univariate analysis was used to analyze the risk factors affecting the prognostic between the two groups of sepsis patients. Cox regression model was used to draw a 28-day survival curve to evaluate the survival of the patients in the two groups.Results:Among 153 sepsis patients in 3 hospitals, the detection rate of pathogenic bacteria was 61.44% (94/153), and Gram-negative bacteria accounted for 79.79% (75/94). The top 3 infection sites were respiratory system, gastrointestinal tract and urinary system, accounted for 32.0%, 28.1% and 18.3%, respectively. In the 3 hospitals, 62.09% (95/153) of patients fully implemented the 1-hour Bundle. The poorly implemented indicators in the 1-hour Bundle were 1-hour blood microbial culture [77.78% (119/153)] and 1-hour antimicrobial application [79.74% (122/153)]. There was no significant difference in the baseline indicators between Bundle compliance and non-compliance groups. Univariate analysis showed that the main prognostic indicators: 28-day survival rate in the Bundle compliance group was significantly higher than that in the Bundle non-compliance group [80.00% (76/95) vs. 62.06% (36/58), χ2= 6.447, P = 0.014]. Secondary evaluation indicators: mean arterial pressure (MAP) at 6 hours and 24 hours in the Bundle compliance group were significantly higher than those in the Bundle non-compliance group [mmHg (1 mmHg = 0.133 kPa): 78.22±11.25 vs. 69.86±14.04, 79.78±11.45 vs. 75.35±12.90]. However, the median length of in hospital stay in the Bundle compliance group was significantly longer than that in the Bundle non-compliance group [days: 13 (17) vs. 6 (11)], with statistically significant differences (all P < 0.05). Bivariate Logistic regression analysis showed that 6 hours and 24 hours MAP were risk factors affecting the prognosis of patients with sepsis [odds ratio ( OR), 95% confidence interval (95% CI): 1.064 (0.994-1.102), 1.032 (1.003-1.063), both P < 0.05]. Conclusions:The 1-hour Bundle compliance rate of ICU patients with sepsis in 3 hospitals of Ziyang City was 62.09%, and the compliance is still to be improved, especially for the 2 aspects of empirical antimicrobial use and microbial culture retention before antimicrobial use. The 28-day survival rate in the Bundle compliance group was significantly higher than that in the Bundle non-compliance group, suggesting that the 1-hour Bundle regimen can improve the prognosis of patients with sepsis.