Point-of-care ultrasound-guided conservative fluid therapy improved the outcome of critically ill patients: a before-and-after study

Abstract Background The danger of volume overload was not yet well understood and appreciated. Point-of-care ultrasound assessment of blood volume was not widely practiced. Methods Critically ill patients managed with point-of-care ultrasound were compared with those managed without, in an intensive care unit (ICU) for medical and surgical cases. Distended internal jugular veins and inferior vena cava with reduced collapsibility were taken as signs of hypervolemia and negative fluid balance became a goal. Results Compared with critically ill patients admitted before application of point-of-care ultrasound assessment (from March, 2019 through October, 2019; 291 cases), cases admitted after (from November, 2019 through June, 2020; 285 cases) had significantly lower in-ICU mortality (34.7% vs 26.7%, p=0.038; Fisher’s exact test), together with a dramatic change from overall positive fluid balance to negative one. Multiple logistic regression showed that cumulative fluid balance during ICU stay, Acute Physiology and Chronic Health Evaluation (APACHE) II score and Sequential Organ Failure Assessment (SOFA) scores on admission were independent risk factors for in-ICU mortality (p<0.001, p<0.001 and p=0.043 respectively). After controlling for APACHE II and SOFA scores on admission, Cox hazard ratio of cases with a negative cumulative fluid balance during ICU stay was 0.683 (95% confidence interval 0.475-0.981; p=0039). Conclusions Point-of-care ultrasound examination of internal jugular veins and inferior vena cava directed fluid therapy to conservative strategy, and negative cumulative fluid balance during ICU stay was associated with a reduced in-ICU mortality.