A prospective observational study to compare and evaluate delta down, aortic velocity time integral variability, and superior vena cava collapsibility index as predictors of fluid responsiveness in patients with supratentorial brain tumors undergoing elective neurosurgery

Abstract

Patients undergoing surgical resection of brain tumors frequently exhibit a spectrum of hemodynamic fluctuations necessitating careful fluid management. This study aimed to evaluate the feasibility of dynamic predictors of fluid responsiveness, such as delta down (DD), aortic velocity time integral variability (VTIAoV), and superior vena cava collapsibility index (SVCCI), in patients undergoing neurosurgery for brain tumors. In this prospective study, 30 patients scheduled to undergo elective neurosurgery for brain tumor resection were enrolled. Baseline measurements of vitals, anesthetic parameters, and study variables were recorded post-induction. Subsequently, patients received a fluid bolus of 10 mL/kg of colloid over 20 min, and measurements were repeated post-loading. Data were presented as mean ± standard deviation. The normally distributed continuous variables were compared using Student’s t-test, with P < 0.05 considered statistically significant. The predictive capability of variables for fluid responsiveness was assessed using Pearson’s coefficient analysis (r). Of the 30 patients, 22 were identified as volume responders (R), while eight were non-responders (NR). DD >5 mmHg effectively distinguished between R and NR (P < 0.001), with a good predictive ability (r = 0.759). SVCCI >38% differentiated R from NR (P < 0.001), with excellent predictability (r = 0.994). Similarly, VTIAoV >20% was also a good predictor (P < 0.05; r = 0.746). Our study revealed that most patients undergoing surgical resection of brain tumors exhibited fluid responsiveness. Among the variables assessed, SVCCI >38% emerged as an excellent predictor, followed by VTIAoV >20% and DD >5 mm Hg, for evaluating fluid status in this population.