- KleinLipo – Tumescent Technique – The tumescent technique is a method that provides local anesthesia to large volumes of subcutaneous fat and thus permits liposuction totally by local anesthesia.
- Dry Technique – The dry technique derived its name from the fact that it did not use injections of local anesthesia into the fat before liposuction.
- Wet Technique – The wet technique required the injection of approximately 100 milliliters of local anesthesia containing epinephrine.
- Super Wet Technique – The super wet technique requires the injection of a volume of dilute local anesthesia that is less than half the volume used for the tumescent technique.
- Ultrasonic (UAL) – Ultrasonic Assisted Liposuction (UAL) requires the use of a large volume of tumescent fluid and uses either a metal probe or metal paddle to deliver ultrasonic energy and heat into subcutaneous fat.
- Power Assisted Techniques (PAL) – PAL devices use power supplied by an electric motor or compressed air to produce either a rapid in-and-out movement or a spinning rotation of an attached liposuction cannula.
The word “tumescent” means swollen and firm. By injecting a large volume of very dilute lidocaine (local anesthetic) and epinephrine (capillary constrictor) into subcutaneous fat, the targeted tissue becomes swollen and firm, or tumescent. The tumescent technique is a method that provides local anesthesia to large volumes of subcutaneous fat and thus permits liposuction totally by local anesthesia. The tumescent technique eliminates both the need for general anesthesia and need for IV narcotics and sedatives. The tumescent technique for liposuction 1) provides local anesthesia, 2) constricts capillaries and prevents surgical blood loss 3) provides fluid to the body by subcutaneous injection so that no IV fluids are needed.
Depending upon the clinical requirements, a tumescent anesthetic solution may contain a 5 to 40 fold dilution of lidocaine found in commercially available formulations of local anesthesia. Commercial solutions of lidocaine used by dentists and anesthesiologists typically contain 1 gram of lidocaine and 1 milligram of epinephrine per 50 milliliters of saline. In contrast, tumescent solutions of local anesthesia contain approximately 1 gram of lidocaine and 1 milligram of epinephrine in 1,000 milliliters of saline. This is a 20 fold dilution of the commercial version of lidocaine and epinephrine.
Dilution & Vasoconstriction Produce Safety
Tumescent liposuction totally by local anesthesia has proven to be extremely safe despite the use of unprecedented large doses of lidocaine and epinephrine. The explanation for this remarkable safety is the extreme dilution of the tumescent local anesthetic solution. Large volumes of dilute epinephrine produce intense constriction of capillaries in the targeted fat, which in turn greatly delays the rate of absorption of lidocaine and epinephrine. Undiluted lidocaine and epinephrine is absorbed into the bloodstream in less than an hour. Tumescent dilution causes widespread capillary constriction which causes the absorption process to be spread over 24 to 36 hours. This reduces peak concentration of lidocaine in the blood, which in turn reduces the potential toxicity of a given dose of lidocaine. Dentists typically use concentrated epinephrine which may cause a rapid heart rate if the epinephrine is rapidly absorbed. When very dilute tumescent epinephrine is used, the wide spread vasoconstriction slows the rate of epinephrine absorption, which in turn prevents an increase in heart rate.
Vasoconstriction Prevents Blood Loss
Profound vasoconstriction (shrinkage of capillary blood vessels) results from the tumescent infiltration of a large volume of dilute epinephrine into subcutaneous fat. Tumescent vasoconstriction is so complete that liposuction can be done with virtually no blood loss. In contrast, the older forms of liposuction used before the invention of the tumescent technique were associated with so much surgical blood loss that autologous blood transfusions were often routine.
Vasoconstriction Prolongs Local Anesthesia
Because the vasoconstriction delays lidocaine absorption, the local anesthetic remains in place in the fat for many hours. This prolonged anesthesia permits surgery for up to 10 hours after infiltration, and provides 24 to 36 hours of significant postoperative analgesia.
Recommended Lidocaine Dosage
Maximum recommended lidocaine dosage is 40 mg/kg to 50 mg/kg for tumescent liposuction when lidocaine is greatly diluted. This is a relatively large dosage compared to the 7 mg/kg which is widely accepted as the “safe maximum dose for lidocaine with epinephrine” that anesthesiologists use. They use non-diluted lidocaine for nerve blocks such as epidural blocks.
A liposuction cannula is a stainless steel tube which is inserted into subcutaneous fat through a small opening or incision in the skin. A microcannula has an outside diameter of less than 3 millimeters (mm). The diameter of microcannulas range from 1 mm to 3 mm. With special designs, microcannulas can remove fat very efficiently. The use of larger cannulas, for example those having an outside diameter ranging from 3 mm to 6 mm require larger incisions which usually leave visible scars.
Adits are small holes in the skin made with round, skin-biopsy punches. Adits are used as access sites, in which the liposuction cannula is passed in and out of during the liposuction process. Adits also facilitate the drainage of blood-tinged anesthetic solution after liposuction. Because of the skin’s ability to stretch, microcannulas can usually fit through a 1.0 mm, 1.5 mm, or 2 mm round hole made in the skin with a skin biopsy punch. Such tiny holes usually disappear without scars after liposuction. Adits are so small that it is not necessary to close them with sutures. Because adits are not closed with sutures, they promote copious postoperative drainage of blood-tinged tumescent anesthesia, which in turn reduces post-operative bruising, tenderness and swelling. Larger cannulas require larger incisions. When larger incisions are closed with sutures, there is delayed drainage, and prolonged swelling, bruising and pain after liposuction.
Dry Technique (no longer used) required general anesthesia. The dry technique derived its name from the fact that it did not use injections of local anesthesia into the fat before liposuction. This technique was abandoned because of the excessive blood loss it caused. Blood composed approximately thirty percent (30%) of the tissue that was removed by liposuction using the dry technique.
Comparing Dry and Tumescent Techniques
The following two abstracts are excerpts from two articles published in the Plastic and Reconstructive Surgery Journal, and are provided to help you compare the differences in blood loss associated with the dry technique and the tumescent technique for liposuction. With the older dry technique for liposuction every patient required hospitalization, general anesthesia and blood transfusion because of the significant blood loss. The newer tumescent technique permitted liposuction in an office setting, totally by local anesthesia, and without any blood loss.
• 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 1500 ml of material removed. All patients were treated in the hospital; 44 percent 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 percent; 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 percent of those who had suction of abdominal-wall fat. (Plastic and Reconstructive Surgery, volume 89, pages 1068-1079,1992).
• Tumescent Technique for Local Anesthesia Improves Safety in Large-Volume Liposuction (by Jeffrey A. Klein, M.D., Capistrano Surgicenter, San Juan Capistrano, CA).
The tumescent technique for local anesthesia improves the safety of large-volume liposuction ( 1,500 ml fo fat) by virtually eliminating surgical blood loss and by completely eliminating the risks of general anesthesia. Results of two prospective studies of large-volume liposuction using the tumescent technique are reported. In 112 patients, the mean lidocaine dosage was 33.3 mg/kg, the mean volume of aspirated material was 2657 ml, and the mean volume of supranatant 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 1000 ml of fat removed, 9.7 ml of whole blood was suctioned. In 31 large volume liposuction patients treated in 1991, the mean difference between preoperative and 1-week postoperative hematocrits was -1.9 percent. The last 87 patients received no parental sedation.(Plastic and Reconstructive Surgery, volume 92, pages 1085-1098,1993).
Wet Technique also required general anesthesia. The wet technique required the injection of approximately 100 milliliters of local anesthesia containing epinephrine. Although the wet technique caused less blood loss than the dry technique, blood loss with the wet technique was still excessive and dangerous. Blood composed approximately 15% to 20% of the tissue removed by liposuction using the wet technique.
Super Wet Technique also requires general anesthesia. The super wet technique requires the injection of a volume of dilute local anesthesia that is less than half the volume used for the tumescent technique. Surgical blood loss with the super wet technique is greater than the tumescent technique but significantly less than the wet technique. Approximately eight percent (8%) of the fluid removed by super wet liposuction is blood.
Ultrasonic Assisted Liposuction (UAL) requires the use of a large volume of tumescent fluid and uses either a metal probe or metal paddle to deliver ultrasonic energy and heat into subcutaneous fat. Internal UAL is the term used to describe the technique where a long metal probe, which may be solid or hollow, is inserted into fat through a large incision. Among those surgeons who do internal UAL, most rely on the use of general anesthesia or heavy IV sedation. Internal UAL has largely been abandoned because of the risk of full-thickness skin burns and severe scaring. The initial reports of internal UAL were unrealistically enthusiastic. Some authors did not report their complications, and others have learned of major UAL complications after publishing their articles. External UAL requires the use of tumescent fluid and uses a metal paddle applied to the skin and directs ultrasonic energy into subcutaneous fat. External UAL does not improve liposuction results and can cause burns to the skin. Because there is insufficient proof of the safety of UAL devices, the FDA (Food & Drug Administration) has never given approval for marketing and advertising of UAL devices to be specifically used for liposuction.
Power Assisted Liposuction (PAL) devices have recently become available. PAL devices use power supplied by an electric motor or compressed air to produce either a rapid in-and-out movement or a spinning rotation of an attached liposuction cannula. Advocates of PAL assert that it makes liposuction easier for the surgeon. While some liposuction surgeons have expressed enthusiasm about PAL, many others remain skeptical about any advantages of PAL. There are no objective scientific publications to support the enthusiastic claims made by manufacturers of PAL devices.