Study objective: To determine whether the plasma concentration of vascular endothelial growth factor (VEGF) is elevated after a common surgical procedure, and if any increase is followed by a reduction in the amount of infused crystalloid fluid in the blood.
Design: Nonrandomized study. Experimental group age-matched to control group.
Setting: Operating room of a large medical research center.
Patients: 10 ASA physical status I, II, and III patients, aged 51 to 94 years, scheduled for hip surgery; and 10 ASA physical status I and II volunteers, aged 53 to 71 years, comprising a control group.
Interventions: Patients and control subjects were given an intravenous volume load of Ringer's acetate solution (12.5 mL/kg for 30 min).
Measurements: The plasma concentrations of C-reactive protein, interleukin-6, interleukin-8 (inflammatory parameters used as biochemical evidence of trauma), and VEGF were measured in patients the morning after the day of the surgery. The area under the curve (AUC) for the plasma dilution was calculated in response to the intravenous fluid.
Main results: VEGF concentration was tripled in the hip group (100.7 +/- 18.5 pg/L vs. 31.9 +/- 7.2 pg/L; p < 0.001) as a consequence of the trauma of surgery. The other inflammatory parameters were also significantly increased. There was no difference in AUC between the two groups during infusion, but after infusion AUC was significantly increased in the hip group versus controls (4.88 vs. 2.8; p = 0.025), suggesting persistence of the infused fluid to remain in the vasculature. AUC was not highly correlated with any of the inflammatory parameters regardless of group during or after infusion.
Conclusions: Intravascular persistence of infused crystalloid is increased after hip surgery despite elevated VEGF levels in plasma.