With the patient standing, the target areas for treatment as well as entry sites for cannula insertion are outlined with a permanent marker. The patient is brought to the procedure table and undergoes sterile preparation. Entry sites are anesthetized locally using 1% lidocaine with 1:100,000 epinephrine. These sites are then incised with a No. 11 blade. A blunt-tipped infiltration cannula or 21-gauge needle is inserted, and tumescent anesthesia fluid is delivered to the subcutaneous space. Rates of infiltration and amounts of fluid delivered vary depending on target area and patient tolerance.
Liposuction aspiration cannulas vary in diameter, tip style, and tip configuration. One innovation is powered liposuction using a motorized cannula. In general, larger cannulas with tapered tips and multiple distal apertures allow easier fat removal but also increase tissue injury. The choice of cannula depends on anatomic site as well as surgeon preference and experience. The cannula is inserted into entry sites with the tip apertures facing downward, away from the dermis. Tunneling with the cannula is performed in linear, even strokes with the surgeon's dominant hand, with the nondominant hand, or “smart hand,” controlling cannula tip position at all times. The majority of suctioning should be aimed parallel to the axis of lymphatic drainage to minimize tissue trauma. Uneven or overly aggressive suctioning can lead to contour irregularities and should be avoided. Endpoints can be measured as the time spent in a given area, the amount of fat suctioned, patient discomfort, and assessment of the target area by palpation. The transition from yellow adipocyte-rich aspirate into fat-sparse serosanguineous tumescent fluid is an additional endpoint. Comparative suctioned aspirate volumes and vital signs are also recorded throughout the procedure.