Quantification of Cannula Influence on Negative Pressure in Syringe Assisted Liposuction.

To make the results of the autologous fat transfer more satisfactory, all parameters of suction, preparation, and reapplication must be well understood. Since syringe-assisted liposuction is frequently used for small-volume procedures, we quantified the influence of the cannula on negative pressure.For these experiments, we used a digital manometer to which a syringe and one of seven different cannulas were connected. Data was collected and analyzed using LabVIEW and Matlab. The volume of our measurement setup was calculated using Boyle-Mariotte's law to ease interpretation, which revealed a volume of 2.82 ± 0.03 mL.We demonstrate that the volume of the measurement setup significantly affects the measurement results. Consequently, we accounted for this factor and calculated the theoretical values accordingly. Statistical analysis shows a significant influence on negative pressure across different cannulas, except for two pairs, which had minimal volume differences. Exemplary, for cannulas with volumes under 1.75 mL, a 2 mL syringe plunger pull was sufficient to create a - 0.5 bar (- 14.8 inHg) negative pressure.The present data indicate that the size of the suction cannula must be considered in syringe-assisted suction to ensure a specific negative pressure is not exceeded. Other research groups have demonstrated that adipocyte vitality and the amount of stromal vascular fraction are reduced by excessively strong negative pressure.