Vascular Reactivity Index as an Effective Predictor of Mortality in Patients With Septic Shock: A Retrospective Study

BACKGROUND

Sepsis is a serious complication that occurs after trauma, burns, and infections, and it is an important cause of death in intensive care unit (ICU) patients. Despite many new measures being proposed for sepsis treatment, its mortality rate remains high; sepsis has become a serious threat to human health, and there is an urgent need to carry out in-depth clinical research related to sepsis. In recent years, it has been found that septic shock-induced vasoplegia is a result of vascular hyporesponsiveness to vasopressors. Therefore, this study intended to establish an objective formula related to vasoplegia that can be used to assess the prognosis of patients and guide clinical treatment.

MATERIALS AND METHODS

A retrospective cohort study was conducted using data from 106 septic shock patients admitted to the ICU of Jining No. 1 People's Hospital from January 2020 to December 2022. The patients were divided into mortality and survival groups based on 28-day survival, and hemodynamics were monitored by the pulse index continuous cardiac output system. The dose and duration of vasopressors, major hemodynamic parameters, lactic acid (Lac) levels, and Sequential Organ Failure Assessment scores were recorded within 48 h of hospital admission. Multifactorial logistic regression was used to analyze the independent risk factors affecting the prognosis of patients, and the predictive value of the vascular response index (VRI) was analyzed by the receiver operating characteristic (ROC) curve.

RESULTS

The differences between the survival and mortality groups in terms of age, sex ratio, body weight, ICU length of stay, distribution of infection sites, underlying disease conditions, baseline Lac levels, and some hemodynamic parameters were not statistically significant (P > .05). The results of multifactorial logistic regression showed that the admission Acute Physiology and Chronic Health Evaluation II score, Lac level at 24 h of treatment, maximal vasoactive inotropic score at 24 h (VISmax24), maximal vasoactive inotropic score at 48 h (VISmax48), and VRI were independent risk factors affecting 28-day mortality. Within 48 h of receiving vasopressor therapy, the VRI was lower in the mortality group than in the survival group. The area under the ROC curve for the VRI was 0.86, and the best cutoff value of the VRI for predicting 28-day mortality was 32.50 (YI = 0.80), with a sensitivity of 0.90, a specificity of 0.90, and a better prediction of mortality than the other indicators.

CONCLUSIONS

The VRI is a good predictor of mortality in patients with septic shock, and a lower VRI indicates more severe vasoplegia, poorer prognosis, and higher mortality in patients with septic shock.