Usefulness of Stroke Volume Index Obtained with the FloTrac/Vigileo System for the Prediction of Acute Kidney Injury After Radical Esophagectomy

Purpose

To assess the impact of stroke volume index (SVI) at the end of esophagectomy upon postoperative renal function.

Methods

We reviewed medical records of 128 patients undergoing esophagectomy. Intraoperative hemodynamics were monitored with the FloTrac sensor/Vigileo monitor system in addition to standard monitors. Patients were divided into two groups according to SVI at the end of surgery: the normal SVI group (n = 76), with SVI ≥ 35 ml/m², and the low SVI group (n = 52), with SVI < 35 ml/m². We compared postoperative renal function, indicated by serum creatinine and estimated glomerular filtration rate, on postoperative days 0 through 3. We also compared numbers of patients who developed postoperative acute kidney injury (AKI).

Results

Although there were no intergroup differences in preoperative renal function or other intraoperative hemodynamic variables, including arterial pressure, central venous pressure, stroke volume variation, a volume of infusion, urine output, and the total intraoperative in–out balance, estimated glomerular filtration rate was significantly lower and serum creatinine was significantly higher in the low SVI group than in the normal SVI group on postoperative days 1 and 2 (P < 0.05). In addition, more patients developed postoperative AKI in the low SVI group than in the normal SVI group (12 of 52 vs. 5 of 76, P = 0.015).

Conclusions

Low SVI at the end of esophagectomy may represent a risk factor for AKI in the early postoperative period. Further studies are required to examine whether maintaining SVI above 35 ml/m² reduces the incidence of AKI after esophagectomy.