The Impact of Early Norepinephrine Use on Outcomes in Patients with Septic Shock: A Retrospective Study Based on the MIMIC IV Database

Abstract

Abstract Background Septic shock is a life-threatening condition that requires timely and effective hemodynamic support. Norepinephrine is a preferred vasopressor in the treatment of septic shock, but there is still controversy regarding the optimal timing of its use. This study aims to assess the impact of norepinephrine administration in the early management of septic shock on short-term and medium-term outcomes. Methods A retrospective analysis was conducted on 3642 septic shock patients from the MIMIC IV 2.2 database. Patients were divided into four groups based on the timing of norepinephrine initiation (within 1 hour, within 3 hours, within 6 hours, and after 6 hours). Mortality rates at 28 days, 90 days, and 180 days, as well as secondary outcome measures such as ICU and hospital length of stay, duration of mechanical ventilation, and urine output were compared among the groups. Survival analysis was employed to evaluate survival rates among different groups. Results Primary Outcome: Survival curves showed that the group receiving norepinephrine within 3 hours had the highest survival rate at 28 days, while the group receiving norepinephrine within 6 hours had the highest survival rates at 90 and 180 days (logrank chi2 25.51, p < 0.001). Secondary Outcome: The group receiving norepinephrine within 1 hour had the shortest ICU length of stay (P < 0.001) and hospital length of stay (P < 0.001). This group also had the shortest duration of mechanical ventilation (P < 0.001) and the least fluid administration (P < 0.001). There was no significant difference in total norepinephrine usage among the groups (P > 0.05). Conclusion Early norepinephrine use, especially within 3 hours, may be associated with lower short-term mortality in patients with septic shock, while initiation within 6 hours may be associated with improved medium-term survival. Early norepinephrine use may also contribute to reduced hospital length of stay, decreased fluid administration, and improved renal perfusion. These findings support considering norepinephrine use in the early management of septic shock, but further research is needed to optimize the timing of its administration.