POCUS Assessment of Fluid Responsiveness in Patients Undergoing Major Surgery

Abstract

Background: Accurate prediction of fluid responsiveness is important during major surgery to optimise haemodynamics and avoid unnecessary fluid administration. This study evaluated point-of-care ultrasonography (POCUS) for predicting fluid responsiveness.

Methods: This prospective observational study included 90 patients undergoing major surgery. IVC respiratory variation and LVOT-VTI were measured before and after a standardised fluid challenge. Patients were classified as responders or non-responders based on change in stroke volume.

Results: Of 90 patients, 52 (57.8%) were responders. Responders had greater IVC respiratory variation (21.8 ± 6.4% vs 13.2 ± 5.1%, p<0.001), lower baseline LVOT-VTI (15.2 ± 2.6 vs 18.1 ± 2.9 cm, p<0.001), and greater change in LVOT-VTI (21.4 ± 7.6% vs 4.3 ± 3.1%, p<0.001). IVC variation >18% predicted fluid responsiveness with an AUC of 0.84, sensitivity of 82.7%, and specificity of 78.9%. LVOT-VTI ≤16.5 cm yielded an AUC of 0.79, sensitivity of 76.9%, and specificity of 73.7%.

Conclusion: POCUS-derived IVC variation and LVOT-VTI showed good predictive ability for fluid responsiveness and may help guide individualised perioperative fluid therapy.