Effect of Multiple Factors on Foam Stability in Foam Sclerotherapy

Foam sclerotherapy is a widely used treatment for varicose veins. However, complications caused by poor foam stability still remain. Most studies ignore multiple influencing factors and only study a single factor. Furthermore, a stable foam preparation using different preparation conditions has not been developed. This study aimed to explore the changing laws of foam stability under multifactorial conditions, and to determine the influence of various factors and optimal preparation conditions on the half-life of foam. A two-level orthogonal test was conducted using four factors (syringe size, surfactant, preparation temperature, and pump speed). Classifications were established as follows: syringe sizes, 2.5 mL and 5 mL; surfactant concentrations, 6% and 0%; preparation temperatures, 20 °C and 10 °C; and pump speeds, 250 mm/s and 125 mm/s, respectively. Eight experimental group (EG) multi-factor combinations were tested. Half-life and drainage time were recorded for analysis. The initial drainage time was within 200 s, but the difference between the groups was also about 200 s. The drainage rate curves of all EGs gradually increased over time. Conversely, the foam half-life extended by about 10 times for the four factors. In addition, the analyses revealed that the order of influence was surfactant >temperature >pump speed >syringe size. The most stable foam preparation was determined. Syringe size, surfactant, temperature, and pump speed had markedly observable influences on foam half-life. A combination of multiple factors can be used to prepare a more stable foam in clinical scenarios and to suitably superimpose favorable conditions to avoid unfavorable conditions.