Introduction

As a prerequisite of any pain-related medical treatment, the matter of anesthesia is of greatest importance. Usually the anesthesiological part of the whole medical treatment has a preparatory character, but is not an essential part of the actual therapy. When tumescent local anesthesia (TLA) was performed for the first time, the primary motivation for the invention was to be able to perform liposuction surgery on an outpatient basis, since most dermatologists in the United States at that time did not have hospital privileges to be able to perform liposuction.

It was a secondary observation to experience a dramatically reduced rate of complications in liposuction. For the first time in medical history the local anesthesia itself became an important active part of the surgical intervention. Comparable to the mobilization of a skin flap, the TLA fluid prepares the surgical site by hydrodissection for a more predictable treatment outcome. Today, understanding of TLA has reached an even more advanced state of importance. As more experience in liposuction surgery enables the surgeon to have a better and more refined imagination in debulking fat and mobilizing different tissue planes and at the same time where to avoid fat removal, we have learned how liposuction surgery should be performed.

Today we have explored the subcutaneous anatomy and have a clear comprehension of the interaction in the subcutaneous honeycomb-type structure of connective tissue in which the fat lobules are embedded. Depending on the body area we can find two, three or four planes of fat layers, each being separated by anatomically described fascias. For a predictable liposuction surgery today, extended knowledge about the subcutaneous anatomy is needed in order to achieve the potential esthetic results in body sculpturing. By conditioning the fat tissue with the TLA fluid, a hydrodissection process will expose the subcutaneous anatomy to the liposuction cannula and will enable the surgeon to orientate himself in the multiple fat tissue levels. Also, the extended amounts of fluid will lead to a homogenization of the fat tissue itself due to the high fluid volume and the resulting diffusion pressure.

Historical Background

When the first liposuction surgery was performed by Arpad and Georgio Fischer in Rome in 1975, a suction unit for abortion was used to curettage and remove fat from the human body through a hollow cannula.

Amongst others, the French surgeons Illouz and Fournier in 1978 started to inject saline solution in fairly minimal amounts (up to 300 ml per surgery) and this showed some improvement with regards to the ease of cannula penetration through the subcutaneous space and also a diminished amount of bleeding. In 1984, to my personal knowledge, Lawrence Field performed an abdominal liposuction on his own wife using a dilute formula of local anesthesia of 0.1%.

In 1985 Jeffrey Klein, a dermatologist from San Juan Capistrano, California, performed his first case using the original TLA formula (Table 45.1). Dr. Klein is trained also in internal medicine, pharmacology, biostatistics and mathematics.

TABLE 45.1 Klein Formula

At that time TLA was called the “tumescent technique for liposuction surgery” or “tumescent liposuction”.

Today¹ we use the term “tumescent local anesthesia” (TLA). The formula is composed of a combination of a local anesthetic drug (short acting), epinephrine, bicarbonate, and optional triamcinolone, diluted in physiologic saline solution. Today we use the so called “Hamburg Formula”, which has been described by Friedrich and Schneider-Affeld (Table 45.2).

TABLE 45.2 Hamburg Formula

The subcutaneous infiltration of large volumes of this formula causes the targeted tissue to become swollen and firm, or tumescent, and permits procedures to be performed on patients without general anesthesia while minimizing blood loss due to the vasoconstrictive effect of epinephrine² and also reduces the resorption of the local anesthesia drug in order to avoid lidocaine toxicity.

The major advantage of the Hamburg Formula is the use of two short-acting local anesthesia drugs, lidocaine and prilocaine, which are metabolized through different pathways. Lidocaine is mostly metabolized in the liver by cytochrome CYP 3A4 to monoethylglycinexylidide (MEGX) and then to glycine xylidide.

Prilocaine is metabolized in the liver but also in the kidneys and the lungs.

Usually the elimination half-life of lidocaine is about 90 to 120 minutes for most patients. This may be prolonged in patients with hepatic impairment or congestive heart failure.

Since patients today expect marked improvements after undergoing a liposuction procedure in terms of body sculpturing, in many cases four to five areas of the body need to be prepared and anesthetized by the TLA. This sets the need for high volumes of TLA fluid in one session for liposuction. Consequently the TLA formula we are using today is a modified Hamburg solution with an exact concentration of 0.038%.

When J. Klein performed his first case with TLA, he used 35 mg/kg bodyweight as a maximum amount of local anesthetic. In a patient of 70 kg the total amount of drug used would be 2450 mg. This is about 5 liters of the classical Klein formula.

Patrick Lillis published data explaining that 55 mg up to 90 mg/kg bodyweight would be safe. Today most of the dedicated uses of TLA use 55 mg/kg of bodyweight. In a 70 kg patient this allows us to use approximately 7.5 liters of the Klein formula. With our sure dilute formula we are able to use approximately 9.5 liters of TLA fluid, still taking into account that we use two different kinds of local anesthetic, which reduces the risk of toxicity to half.

Preoperative Preparation

The prepared bags of TLA solution are connected to an infusion pump which should be able to determine the speed of infiltration, currently infiltrated amount, and maximum amount of fluid. Preferably the solution should be preheated, at least to room temperature. While the infiltration process is ongoing the patient should be kept in warm blankets and supplied with a warm air system. Blunt or sharp cannulas can be used as infiltration devices; these are called rainbow cannulas. We use a sharp needle system using 12 outlets simultaneously so a slow administration of fluid can be accomplished in an acceptably short period of time (Fig. 45.1). At an infiltration speed of 200 ml/min, 10 liters of TLA fluid can be infiltrated in about 50 minutes (Fig. 45.2 and Box 45.1).

FIG. 45.1 Administration devices for TLA.

FIG. 45.2 Infiltration towards the state of tumescence.

A quick manner of fluid infiltration will lead in the first step to an “interseptal hydrodissection” (Fig. 45.3), since these tissue planes offer the lowest resistance for the TLA fluid to spread. After a short time, depending on the rising interstitial tissue pressure, the TLA fluid will penetrate the fascias and will surround the fat lobules, which we call “paralobular distribution” (Fig. 45.4). Increasing amounts of fluid will cause the fat lobules to absorb the TLA fluid. This stage is called the “intralobular penetration” (Fig. 45.5). After more and more fluid is added, the complete extent of all the fat levels is flooded by the TLA fluid, which after 30 minutes of diffusion we call the “state of tumescence” (Fig. 45.6).

FIG. 45.3 Interseptal hydrodissection.

FIG. 45.4 Paralobular distribution.

FIG. 45.5 Intralobural penetration and homogenization of the subcutaneous tissue.

FIG. 45.6 Physiodynamics of tumescent fluid.

How to know how much to use? Which is the best amount of fluid for a safe and predictable liposuction surgery?

In order to standardize the individual circumstances of a patient as well as tissue character, enough TLA fluid is needed to achieve a situation of maximum firmness of the skin surface. This could be compared to the firmness of an orange or a watermelon.

A time of penetration allows the fluid to distribute throughout all levels of the subcutaneous anatomy, which leads to a situation of “homogenization of the fat tissue”. When after 30 minutes of penetration time firmness on the skin surface still exists, then the “state of tumescence” has been achieved. If the skin surface should show severe softness, additional fluid infiltration is indicated in order to avoid unnecessary shearing and avulsion forces during the liposuction surgery.

Surgical Technique

For a superior liposuction surgery outcome, smooth skin surfaces as well as firm and tight skin textures without irregularities of the outer circumferential lines are essential. When fat tissue presents itself in a unique homogenized kind, the aspiration process will also show a unique kind of aspiration characteristic. If we have no homogenization of the fat tissue, we will not able to expect an even tissue aspiration. In cooking, this compares to raw potatoes, cooked potatoes, and mashed potatoes. Each state of potato will demonstrate its own aspiration characteristics; mixing these three types will never offer evenness after removal due to aspiration.

Furthermore, the hydrodissection of the subcutaneous space separates the horizontal fascia planes from the different fat compartments. This allows the surgeon to perform a fat debulking procedure under anatomical considerations at different levels (Fig. 45.7).

FIG. 45.7 Fat removal in the state of homogenization of the subcutaneous tissue.

Optimizing Outcomes

Performing liposuction surgery under solely local anesthetic treatment, relevant aspects of the surgical performance for an improved procedure and cosmetic outcome need to be addressed.

Active positioning of the patient during surgery performed under local anesthesia allows the patient to move on the operating table; a patient can stretch, bend, tense muscles, and will position as advised actively, so the surgeon is able to shape and sculpt a three-dimensional part of the human body. By tensing the muscle, the underlying firmness gives the surgeon better judgment in regard to the depth of anatomical levels.

In regard to safety, TLA demonstrates the issues of local anesthesia. There is always a range of action. This disadvantage in regard to safety is a very important point. A potential injury from perforation of the underlying structures (such as the abdominal wall) by the liposuction cannula would be noticed by the patient immediately, so undesired injuries can be prohibited before they even happen. Also, the softening effect on the fat by the TLA fluid severely reduces the force needed to push the liposuction cannula forward. This increases the surgeon’s control of his own fine-motor-sensitivity (Fig. 45.8).

FIG. 45.8 Endoscopic view of best case situation after liposuction. Completely “fat-free“ subcutaneous field including unharmed connective tissue fibers of the dermis.

After a liposuction under TLA, the situation of open drainage will occur; having extensive amounts of saline solution present in the surgical area has an exceptional advantage. Blood will not coagulate in the presence of saline solution and therefore the postoperative liposuction period will show a pronounced wash-out situation with the open drainage of reddish-colored fluid through the distal incisions of the surgical field. This leads to less bruising, less pain, and less swelling, as well as a lesser potential for infection during the postoperative period (Fig. 45.9).

FIG. 45.9 Atraumatic lipoaspiration in tumescent local anesthesia uses an open drainage technique. The higher the volume of the tumescent fluid, the more intense the wash-out effect will be.

Due to the biopharmacologic properties of local anesthetic drugs, they all demonstrate a pronounced bacteriostatic activity, which also enables the TLA solution to have this bacteriostatic character. By using this TLA formula, we are actually using an antiseptic fluid, which reduces the risk of potential bacterial infection.

In many cases using TLA for liposuction, additional anesthesiologic therapy is beneficial. The use of TLA still allows the use of additional sedative drugs like midazolam, remifentanil, or propofol. These drugs should be administered by an experienced anesthesiologist. In conclusion, this combination of TLA with anesthesiologic therapy allows the performance of liposuction with the comfort of a general anesthesia but under local anesthesia.

Postoperative Care

It is mandatory and should be possible that the patient walks around immediately to prevent deep vein thrombosis and to use the muscle pump for better drainage. As the small incisions are left open, thick gauze pads or diapers are used on top of the compression garment for the first 2 days. Mild lymphatic drainage beginning on the very first day is recommended and continued for 2 weeks or longer.

Complications and Contraindications

See Box 45.2.