Relationship between Doppler snuffbox resistive index and systemic vascular resistance in patients with sepsis

Background: This study aimed to explore whether the snuffbox resistive index (SBRI) measured by ultrasound can serve as an indicator of vasoplegia in patients with sepsis. Methods: Patients admitted to the intensive care unit with sepsis were enrolled, and their systemic vascular resistance index (SVRI) was measured using a pulse contour cardiac output monitor. The SBRI and peripheral perfusion index (PI) were measured immediately after measuring the SVRI. The Pearson correlation coefficient (r) was used to test both the correlation between patients’ SBRI and SVRI, and the correlation between SBRI and PI. Results: Of the 76 patients with sepsis, 53 (70%) were male. A total of 166 sets of measurements were obtained. The mean (±standard deviation SD) cardiac index was 3.01 (±0.98) L/min/m², the mean (±SD) SVRI was 2367 (±914) dyn·s·m²/cm 5 , and the mean (±SD) SBRI measured by ultrasound was 0.9 (±0.14). The SBRI was not correlated with the SVRI (r = 0.003, P = 0.956) but was moderately negatively correlated with the PI (r = −0.516, P < 0.001). Conclusions: SBRI was not correlated with the SVRI but was moderately negatively correlated with the PI. Caution should be made when the SBRI is used to evaluate systemic vascular status.