Microlipo, or The Tumescent Technique

Features of the Tumescent technique

1. Dilution and Vasoconstriction
The tumescent liposuction approach typically uses large volumes of a diluted solution also containing lidocaine and epinephrine. The method is considered extremely safe due to the extreme dilution of these two anaesthesia solutions, and a constriction of capillaries in the area of fat which delays their absorption. In contrast, undiluted lidocaine and epinephrine can be absorbed into the bloodstream in less than an hour. The increase in absorption time, spread over 24-36 hours, reduces peak concentration of lidocaine in the blood, which then reduces the toxicity of the dose of lidocaine. The use of dilute epinephrine stops the heart rate increasing due to the delay in absorption caused by extensive vasoconstriction.

2. Prevention Of Blood Loss
The injection of large volumes of dilute local anaesthesia causes a shrinkage of the capillary blood vessels. This has practically eliminated blood loss during or after the procedure, a common occurrence in older methods often resulting in the patient needing a blood transfusion.

3. Reduction Of Postoperative Pain
Due to the delay in absorption of lidocaine, the anaesthetic remains in the subcutaneous fat area for several hours. The extended anaesthetic effect allows surgery for up to 10 hours, and 24-36 hours of pain relief after the operation. The need for heavy-duty painkillers is more often than not eliminated.

4. Use Of Microcannulae
During liposuction a cannula is inserted into fat layers just under the skin. In older methods of liposuction, typically, cannulae were over 6mm in diameter, often causing extreme blood loss and postoperative skin disfigurations. The tumescent technique uses microcannula with a diameter of less than 2.3mm, resulting in dramatically less scarring and a smoother end result.

5. Use Of Adits
Adits are tiny holes made in the skin through which the cannulae are passed in and out during the liposuction process. Postoperatively, adits allow the drainage of blood-tinged residual local anaesthetic, which dramatically reduces scarring and bruising, tenderness and swelling. The adits are so small that they do not require sutures and hence enable easy drainage. Adits are made using skin-biopsy punches, and because the skin is stretchable, microcannulae can fit through these adits (usually anywhere between 1.0 to 2mm round).

Dry Technique

Although this technique is no longer used it’s important to understand how liposuction has evolved and the industry’s improved safety and patient satisfaction records. This technique required general anaesthesia and did not use injections of local anaesthesia into the fat before liposuction, causing extensive blood loss. It was eventually abandoned for safety reasons.

Dry Vs. Tumescent

There’s no doubt the tumescent technique of liposuction is dramatically safer than the dry method in terms of blood loss and skin smoothness. Whilst the dry technique requires hospitalisation, general anaesthetic and possibly blood transfusions, the tumescent technique is far less daunting. Tumescent surgery can even be conducted in an office setting, using only local anaesthesia, with practically no blood loss. Almost 30% of the tissue removed through the dry method was composed of blood, which in today’s day and age is an unacceptable amount.
To demonstrate the difference here are two abstracts from The Plastic and Reconstructive Surgery Journal, one of the leading plastic surgery publications globally.

Large-Volume Suction Lipectomy: An Analysis of 108 Patients (by Eugene H. Courtiss, M.D., et al., Division of Plastic Surgery, Department of Surgery, Harvard Medical School, Boston, MA).
“We have treated 108 patients who had over 1500ml of material removed. All patients were treated in the hospital; 44% were admitted after surgery. A total of 227 units of autologous and 2 units of homologous blood were transfused. As measured by a computerized monitor, the average amount of blood in the material removed from thighs was 30%; from abdomens, the blood loss was 45 percent. No complications were encountered. A few patients developed undesirable sequelae, the most common of which was seroma formation, which occurred in 19% of those who had suction of abdominal-wall fat.” (Plastic and Reconstructive Surgery, volume 89, pages 1068-1079,1992).

Tumescent Technique for Local Anaesthesia Improves Safety in Large-Volume Liposuction (by Jeffrey A. Klein, M.D., Capistrano Surgicenter, San Juan Capistrano, CA).
“The tumescent technique for local anaesthesia improves the safety of large-volume liposuction ( 1,500 ml of fat) by virtually eliminating surgical blood loss and by completely eliminating the risks of general anaesthesia. Results of two prospective studies of large-volume liposuction using the tumescent technique are reported. In 112 patients, the mean lidocaine dosage was 33.3mg/kg, the mean volume of aspirated material was 2657ml, and the mean volume of supernatant fat was 1945 ml. All patients were treated as outpatients. There were no hospitalizations. There were no transfusions. There were no complications. There were no seromas. The mean volume of whole blood aspirated by liposuction was 18.5 ml. For each 1000ml of fat removed, 9.7ml of whole blood was suctioned. In 31 large volume liposuction patients treated in 1991, the mean difference between preoperative and 1-week postoperative haematocrits was -1.9%. The last 87 patients received no parenteral sedation.” (Plastic and Reconstructive Surgery, volume 92, pages 1085-1098,1993).

Wet Technique

The wet technique also requires general anaesthetic, however it was used in combination with about 100ml of local anaesthesia and with epinephrine. Although the blood loss in this technique was less than the dry method it was still at very high levels – 15-20% of the tissue removed consisted of blood.

Super Wet Technique

Further refinement resulted in the introduction of the super wet technique, which also used general anaesthesia, but with a greater amount of dilute local anaesthesia. Surgical blood loss via this technique was found to be only 8% of the total tissue removed; a marked reduction from the dry and wet techniques, but higher than the tumescent approach.

Ultrasonic Assisted Liposuction (UAL) – First & Second Generation

This technique, also abandoned, used large volumes of tumescent fluid and either a metal probe or a metal paddle to administer ultrasonic heat and energy into under-the- skin fat.
Internal UAL used a metal probe that could be either solid or hollow to be inserted into the fat through a large incision. The patient would have to be under general anaesthesia or extremely heavy sedation. The primary risk with this kind of method was burning of the skin, often resulting in irreversible scarring.

External UAL used the tumescent solution with a metal paddle directly on the skin, directing ultrasonic heat into the subcutaneous layers. Surgeons discovered over time this method also caused burned the skin and did not improve the liposuction results.
It is interesting to note that the U.S. Food and Drug Administration has never given approval for marketing or advertising of UAL devices for liposuction due to safety concerns.

Vaser lipo

This method is a third-generation internal UAL delivered through cannulae. It was used for patients typically with a BMI under 25kg/m2. It was not possible to use this method on larger areas due to the high risk of burns, scarring and other complications associated with UAL.