The study evaluated superior mesenteric artery (SMA) hemodynamic changes in 103 patients with acute purulent appendicitis (ASA) diagnosed by ultrasound and pathology in 2015–2022 versus 98 healthy controls. Parameters measured included peak systolic velocity (PSV), end-diastolic velocity (EDV), resistance index (RI) and systolic/diastolic ratio (S/D). In the ASA group, PSV, RI and S/D were significantly higher (p < 0.05): median PSV 215.9 cm/s (IQR 169.1–233.7), RI 0.83 (IQR 0.79–0.85), S/D 5.8 (IQR 4.7–6.7); in controls PSV 132.8 cm/s (IQR 118.1–155.0), RI 0.73 (IQR 0.69–0.77), S/D 3.7 (IQR 3.2–4.4). ROC analysis for PSV showed an optimal cut-off value of 157.5 cm/s with an area under the curve (AUC) of 0.89. Ultrasound measurement of SMA hemodynamics is of significant value in the diagnosis of ASA, especially when direct visualization of the appendix is limited. Increased PSV in SMA is related to systemic inflammatory response, oxidative stress and expression of molecules associated with ferroptosis. This non-invasive approach helps in early diagnosis and clinical decision-making.