The following is a summary of “Ability of diastolic arterial pressure to better characterize the severity of septic shock when adjusted for heart rate and norepinephrine dose,” published in the March 2025 issue of Annals of Intensive Care by Goury et al.

Septic shock’s reduced vasomotor tone, often caused by poor vascular response to norepinephrine (NE), is not accurately reflected by the diastolic arterial pressure (DAP) /heart rate (HR) ratio despite its link to vasomotor tone.  

Researchers conducted a retrospective study to determine whether index of vascular responsiveness to NE (VNERi), calculated as DAP/ (NE dose × HR), showed a stronger association with outcomes than DAP, DAP/HR, or mean arterial pressure (MAP)/NE dose in individuals with persistent hypotension despite NE.  

They performed a post-hoc analysis using the ANDROMEDA-SHOCK database. Hemodynamic variables and initial NE doses were documented at the randomization time point within 4 hours of septic shock diagnosis. The NE doses were measured in µg/kg/min using the bitartrate NE formulation. A multivariate model was utilized to analyze the associations between these variables and key clinical outcomes, including in-hospital mortality, vasopressor-free days, and renal replacement therapy (RRT)-free days up to day 28.  

The results showed that the database included 424 individuals with septic shock receiving NE. The median DAP was 52 mmHg [interquartile range (IQR): 45–50], and the median NE dose at inclusion was 0.2 µg/kg/min [IQR: 0.1–0.4]. In-hospital mortality was 43%. The VNERi had the strongest association with in-hospital mortality compared to DAP, DAP/HR, and MAP/NE dose, making it the most significant covariate in the multivariate model. Similar associations were observed for vasopressor-free days and RRT-free days up to day 28. The model identified an inverted J-shaped relationship between in-hospital mortality and VNERi, with a nadir at 6.7, below which mortality increased.  

Investigators concluded that VNERi showed the strongest link to outcomes in patients with early septic shock on NE compared to other markers. 

Source: annalsofintensivecare.springeropen.com/articles/10.1186/s13613-025-01454-y