Renal Resistive Index in Patients with Septic Shock: Changes in the Renal Resistive Index as a Parameter of Tissue Perfusion in the Assessment of Response to Treatment during Resuscitation of Patients with Septic Shock; a Prospective Observational Study

Abstract

BackgroundSeptic shock, a complication characterized by altered tissue perfusion, is associated with high mortality if left untreated. Renal resistive index (RRI) reflects changes in intrarenal perfusion. Therefore, the present study aimed at investigating changes in RRI during resuscitation of patients with septic shock and evaluating its relationship with other micro- and macrociculatory perfusion parameters.MethodsThe present prospective observational study was performed on all patients referring to the emergency department intensive care unit (ED-ICU) diagnosed with septic shock from July 2018 to September 2019. Demographic characteristics of the study subjects were recorded and their hemodynamic, paraclinical, and RRI values were measured at three time points of on arrival, and 30 and 120 minutes and six hours after admission, by ultrasound.ResultsA total of 109 subjects entered data analysis; their mean age was 67.62 ± 14.67 years, of which 65 (59.1) were male. The RRI values were 0.71 ± 0.27, on arrival, at 30 and 0.70 ± 0.1 on 60 minutes, at six hours after treatment onset, respectively, showing that RRI values decreased during the study, which was statistically significant (P-value= 0.00). ConclusionA decrease in RRI value during resuscitation is associated with an increase in MAP in patients with septic shock. Accordingly, RRI can be used as an indicator of microcirculatory perfusion in the treatment process and volume assessment of patients with septic shock.