Liposuction Techniques Treatment & Management

Markings

Make markings using a surgical marker to indicate areas to be treated while the patient is in the standing position. Most surgeons use topographic-type markings to indicate areas of maximal bulge centrally with successive concentric circles farther away to indicate adjacent areas where the liposuction should be tapered gently at the periphery. Once the patient is recumbent, lipodystrophic areas become distorted and shift, making discerning the areas to be treated much more difficult. Thus, the patient must be marked prior to positioning, almost always in the standing position. If the patient also understands the markings, he or she can help confirm the areas of treatment and can be involved in the decision-making process, which helps increase patient satisfaction. Zones of adherence and depressions frequently are drawn with a marker of another color to indicate avoidance areas. ^[6]

Port sites also should be marked with the patient in the standing position. This allows for placement in strategic areas that can be camouflaged by undergarments, shorts, or skirt lines. Plan 2-3 port sites for each problem area to allow cross-tunneling aspiration to minimize surface abnormalities.

Special considerations

Liposuction came under especially close scrutiny due to tragic circumstances surrounding several large-volume procedures. ^{[7, 8]} These issues revolved around fluid delivery and lidocaine/epinephrine dosing. With large-volume liposuction, defined by the American Society of Plastic Surgeons as greater than 5 L, significantly greater fluid shifts occur as a result of tumescent fluid infusion and fat removal. Some have estimated the amount of infusate that is absorbed by the body to be 1 mL/1 mL fat removed and that 20% of the tumescent fluid is removed through suction.

The recommendations for perioperative intravenous (IV) fluids have varied in the literature. Some have recommended no additional IV fluids when using the tumescent technique; others have suggested only maintenance fluids, and yet others, a total infusion volume of 2-3 mL (including infusate, IV, and postoperative fluids) per milliliter of aspirate removed. Other recommendations using the superwet technique involve maintenance fluids and wetting solution if less than 5 L are to be aspirated and maintenance fluids, wetting solutions, and 0.25 mL intravenous crystalloid per each milliliter aspirated after 5 L.

Recent research has utilized the intraoperative fluid ratio (superwet solution volume plus intraoperative IV fluid infused divided by total aspiration volume) to further assess fluid administration and patient safety. No adverse consequences of fluid overload were seen in small volumes of liposuction (< 5 L) with ratios of 1.8 and large-volume liposuction (>5 L) with ratios of 1.2. ^[9]

When epinephrine is used for the tumescent fluid, it can be used safely in much higher dosages than traditionally recommended. The maximum safe dose of epinephrine is < 0.7 mg/kg (ie, when given systemically or administered parenterally). Doses for lidocaine approximating 35 mg/kg body weight have been suggested as safe, with peak plasma concentrations occurring at approximately 12 hours postprocedure when infused into subcutaneous fat for a liposuction procedure. These concentrations usually occur at < 2 mcg/mL, which is lower than that observed with doses of 3-5 mcg/mL (with which toxicity can be observed).

Equipment

An extensive number of liposuction cannulas are available to the surgeon that can be used depending on the area, volume, and type of tissue to be treated. Currently, the most frequently used cannulas are either based upon the Mercedes design (contains 3 windows, 120° apart, with a blunt tip; see the image below) or have downward-facing openings to prevent suctioning of superficial fat, which can create undesirable contour irregularities. Most cannulas used are blunt tipped to limit damage to surrounding soft tissues.

Cannula shaft lengths also vary significantly to allow for proper access to the area to be treated. Areas such as the face and neck are best treated by shorter lengths, while the thighs, hip, back, and abdomen often are treated by longer length cannulas to obtain sufficient reach. Smaller cannula sizes and openings allow for more controlled fat removal with less opportunity for development of contour deformities. Generally, for larger treatment areas, such as the truncal area, 3- to 6-mm cannulas are used, while in areas that require removal of smaller amounts, such as the face and neck, 1.5-, 2.4-, and 3.8-mm cannulas frequently are used.

Other tips (eg, tiger-tip cannula, saber-toothed cannula) also have been created to help allow for more aggressive removal, especially after secondary procedures or with tough fibrous tissue. Other styles of cannula (eg, loop-de-loop, pickle fork) have been constructed to treat areas of cellulite, disrupting the septa. Several of these also provide mechanisms to re-inject fat after aspiration to correct contour and irregularities. Recently, power-assisted cannulas, with a protected rotating tip, have been developed (eg, Micro-Aire) to assist in easier removal of fat with less physical strain on the operating surgeon. ^[10]

Anesthesia

In the authors' practice, most lipoplasty procedures are performed under general anesthesia with the tumescent or superwet technique. This allows both for ease of repositioning and minimal or no use of lidocaine to prevent toxicity issues postoperatively. Additionally, the authors use body warmers and blankets when possible, along with warmed infusate solution, to help maintain core temperature. To aid in the prevention of deep vein thrombosis or pulmonary embolism, pneumatic compression devices are used in all patients when the procedure is anticipated to last longer than 1 hour. These devices also may be used around the arm if both legs are being treated with liposuction.

Positioning

For most lipoplasty procedures performed by the authors, the supine lateral decubitus (SLD) position is attempted. This allows relatively easy access to and mobility for almost all areas to be treated. Prior to sterile preparation, the patient is circumferentially prepared and then placed supine on sterile blankets, if significant posterior access is necessary. Sterile leg stockinettes wrapped with sterile Coban tape are used to keep the underlying compression stockings away from the sterile field. As the procedure requires, the patient is placed into the supine position, and the patient's knee and hip are flexed and rotated to allow for access to the hip and gluteal areas. This has the added benefit of avoiding repositioning when multiple sites are to be treated. The anesthesiologist also has direct access to the endotracheal tube if critical issues arise that need immediate attention.

Skin preparation

Prepare the patient's skin with a 10-minute scrub with povidone-iodine solution (Betadine) followed with povidone-iodine paint and drape the area to be treated. If rotation of the hips and legs is needed, use a sterile stockinette and self-adherent wraps (eg, Coban wraps) to keep the distal lower extremities sterile after circumferential preparation to allow for manipulation of the lower extremities as needed. For antibiotic prophylaxis, the authors administer a first-generation cephalosporin to cover skin flora 1 hour prior to surgery.

Infiltration and operative technique

Historically, 4 types of wetting solutions have been used for liposuction: dry, wet, superwet, and tumescent. The essential difference between these techniques focuses on the amount of infusate into the tissues and the resultant blood loss as a percentage of aspirated fluid. The dry technique involves no infused fluid and results in approximately 25-40% blood loss of the volume removed. The wet technique uses infusion of 100-300 mL of fluid (with or without epinephrine) into each site to be treated, resulting in a reduction in blood loss of 10-30% of aspirate without epinephrine and 15% with epinephrine. These two techniques have fallen out of favor and have been replaced by superwet and tumescent techniques due to levels of blood loss.

The superwet technique involves instillation of fluid with epinephrine in equal volume to the amount to be removed, eg, 1:1 ratio (supranatant fat and infranatant fluid). Ranges of blood loss have been reported at 1-4% of aspirate. The tumescent technique involves infusions of fluid with epinephrine until the targeted tissue is engorged and tense with fluid (estimated at 2-3 mL/mL removed). Blood loss estimates have been approximated at 1% or less. The American Society of Plastic Surgeons Practice Advisory Committee has recommended use of the superwet technique to reduce the need for infiltrating solutions and the surgical risk. Approximately 50-70% of the infused fluid is estimated to remain at the end of the lipoplasty procedure.

The two major formulas for tumescent infiltration for liposuction are the Tumescent Formula (Klein [Hunstad]) and Modified Tumescent Formula (Hunstad). The Tumescent Formula combines 1 L of normal saline with 50 mL of 1% lidocaine, 1 mL (1 amp) of 1:1000 epinephrine, and 12.5 mL of 8.4% sodium bicarbonate. In this formula, the bicarbonate is added to counteract the acidic nature of the saline solution to decrease the pain of the injection and increase analgesic potency.

Alternatively, the modified formula is composed of 1 L of lactated Ringer solution with the same lidocaine and epinephrine solution as in the standard formula. Because the pH of the lactated Ringer solution is higher than that of the saline solution, the need for the bicarbonate is obviated. In both concentrations, a final concentration of lidocaine of 0.05% and epinephrine of 1:1,000,000 is created. Some surgeons omit the lidocaine component of the solution when the patient is undergoing general anesthesia to further reduce potential lidocaine toxicity issues. The authors also take the additional measure of warming the injectate to 38-40°C to help maintain core body temperature and prevent hypothermia.

Infiltration begins by creating a small stab incision, just enough to accommodate the infiltration needle. Alternatively, some use an awl or punch device to attempt to decrease bleeding at the local site. Blunt-tipped cannulas of varying lengths are used to infiltrate the fluid into the desired deep subcutaneous adipose layer using either a handpiece or foot pedal to control administration. When using the tumescent technique, infuse the fluid until the skin is uniformly distended and firm at the operative site. After 8-10 minutes, the skin should become blanched from the vasoconstriction. Commonly, back pressure causes transient spurting of fluid from the ports.

Pretunneling can help increase cannula control by establishing desired planes of fat removal before suction is activated. This concept, delineated by Mladick, involves using a larger cannula (6 mm on the trunk/extremities and 3-4 mm on the face) that is passed many times without suction into the most superficial layer of the desired area of removal. This helps prevent inadvertent removal in the subdermal fat layer, which can result in contour irregularities. Ultimately, this can assist in increasing precision in accurate and safe removal of fat.

Cross tunneling is an additional technique helpful in improving cosmetic results of lipoplasty. The technique of cross tunneling involves the use and creation of at least two port sites at right angles to treat an area of adiposity. The use of multiple port sites provides for better contouring and feathering of edges and allows for more thorough treatment of problem areas.

Fat layers generally are treated from deep to superficial in sequence. Parallel tracks are developed in standard fashion, and as the procedure is moved more superficially, cannula size can be decreased along with suction intensity to help decrease risk of irregularity to surface layers. Take care to keep the tip openings facing downward or deep to prevent suction of superficial fat near the dermis, which can result in dimpling. Additionally, moving the tip more rapidly helps prevent dermal deformity. A technique called mesh undermining also can be used to recontour transition and treatment area edges. A blunt cannula is used without suction and is passed laterally into surrounding transition areas, loosening adjacent tissue and softening the edge of treated and untreated areas.

Deep versus superficial

The most traditional liposuction treatment involves removal of the deeper layers of fat. However, superficial liposuction is performed in an attempt to improve skin contour in individuals with flaccid skin or cellulite in specific areas. With this method, a very narrow cannula is used to make multiple closely spaced passes in the subdermal fat to undermine the affected tissue. The hope with this technique is that superficial treatment initiates skin retraction. Pseudoptosis of the posterior neck and/or jowls, dorsal back, outer thigh, banana roll, abdomen, flank and/or lumbar rolls, breasts, and inner thigh and/or arm have been stated as most favorable for treatment. Individuals with cellulite of the outer and anterior thighs have been shown to be most likely to respond well with changes.

Several indications help determine when to stop liposuction to an area. Assessment of symmetry (if bilateral), shape, and overall smooth contour helps determine end points of the procedure. As more adipose tissue is removed, skin pinch testing should become less than an inch and should be symmetric between sides. If both sides were fairly equal prior to surgery and infusate was similar, amount of aspirate also should be close in volume on both sides. With removal of more of the remaining fat, stroking of the cannula changes to a grittier feel as it passes against the remaining fibrous septa.

After completion, the soft tissue is rolled manually with a roller or a rolled laparotomy sponge against the skin to remove persistent tumescent fluid and decrease postoperative drainage from the port sites. This adds to patient comfort. Port sides can be re-excised to improve cosmesis, and closure can be completed with either a deep dermal absorbable suture or simple nylon sutures that are removed 1 week postoperatively. Inform the patient to expect significant postoperative drainage from port sites early; this tapers significantly during the first 1-2 days. For this reason, many surgeons use absorbable dressings (ABD dressings) to help prevent soilage of compressive binders and/or dressings. Although not all physicians use dressings, the authors use compression garments, such as girdles, binders, compression hose, or Ace wraps, postoperatively. They have observed more rapid improvement in resolution of edema and ecchymosis with these garments.

Although debated, some argue that compression also helps to provide support for the recently undermined skin to allow for better postoperative contouring while the skin is re-adhering to deeper layers. Use of self-adhering foam (eg, Reston foam) has been very popular after liposuction. However, the adhesive backing is extremely adherent and cases of blistering and hyperpigmentation have occurred due to shearing forces on the foam. To decrease this risk, many apply a light coating of antibiotic ointment to the adhesive side. However, the manufacturing company of the foam (3M) does not recommend that the foam be applied to the skin, which has resulted in fewer surgeons using the foam postoperatively. The authors' practice has been not to use the foam postoperatively.

Patients routinely are treated on an outpatient basis unless the lipoaspirate is >5 L or another concomitant procedure is performed that warrants closer observation. Discharge patients with an informed caregiver and instruct them on drainage and compression garment use. Patients should continue ambulation and light activity to deter deep vein thrombosis and its associated complications. The patient may shower after 2-3 days and replace the garment for continued use. Under most circumstances, the patient may return to work after 1 week but should avoid strenuous activity or working out for 2-3 weeks depending on the areas and amount treated. Garments should be worn for at least 2 weeks continuously. Some surgeons use garments to improve postoperative edema and contour for as many as 6 weeks after surgery. ^[11]

The development and use of ultrasound-assisted liposuction (UAL) as a surgical technique has allowed for body contouring through the liquefaction of fat. ^[12]  While initially used with solid probe devices, hollow cannulas are more frequently used as the mainstay of current therapy. Fat is eliminated through the process of cavitation, in which ultrasonic frequencies form microcavities or bubbles within low-density tissues (fat or water) that allow cell membrane disruption. Because this process can create significant amounts of heat, two concepts are essential in the treatment with this method of lipoplasty: (1) use only in the presence in a wet environment or solution (for control of temperature and the improvement of cavitation), and (2) apply ultrasonic energy to the cannula only while the cannula is in motion to avoid thermal burns/injury.

Many surgeons believe that UAL is best considered not as a replacement for suction-assisted liposuction (SAL) but rather as a compliment to decrease effort and surgeon workload during treatment, especially in fibrous areas or with large volumes. Some also feel that UAL results in improved feathering or contouring to allow for a smoother effect on surrounding fatty tissue to be treated. ^[13]

Vibration amplification of sound energy at resonance (VASER) liposuction is a third-generation UAL technology that provides a less invasive means of carrying out superficial and deep lipectomy. ^{[14, 15]}

A study by Tran et al of 261 patients who underwent VASER liposuction found the overall complication rate to be 4.6%. Complications, at minimum 6-month follow-up, included contour irregularity (1.9%), seroma (0.8%), cellulitis (0.8%), pigmentation changes (0.4%), and electrolyte imbalance (0.4%). ^[14]

Power-assisted liposuction (PAL) uses a small rotating blade at the tip of the aspiration cannula. As with UAL, this variant is designed to decrease the level of effort required to perform the procedure. ^[10]

The aforementioned study by Stein et al indicated that the proportion of UAL procedures has decreased, making up 5% of liposuction operations between 2005 and 2014 and 2% of procedures between 2015 and 2021. Over those two periods, the proportion of PAL procedures increased from 24% to 40%. ^[1]

Laser-assisted liposuction (LAL) has various proprietary names, including Smartlipo, Slimlipo, and Coollipo. The principle is similar in that laser energy is introduced into the subcutaneous tissue and the deep portion of the dermis. Advantages are reported to include ease of procedure, increased fat removal and decreased recovery. Also, as with UAL, the energy is applied to the dermis to increase skin tightening. The efficacy of this continues to be studied, but skin tightening appears to be more reliably obtained with the use of the laser energy application. ^[16]

Another modality is water jet liposuction. This technique uses high pressure water jets to break down the fat tissue and facilitate aspiration.

The most common complications after lipoplasty are contour deformities and skin irregularities. Because they may lessen as swelling and edema resides, under most situations, the authors recommend waiting 6 months for treatment or revision if necessary. Other complications include seromas, hematomas, hyperpigmentation and/or dyschromias, skin slough and/or necrosis, infection (chronic and/or acute), perforated intra-abdominal structures, hypesthesias and/or dysesthesias, fat embolism, pulmonary edema and/or adult respiratory distress syndrome (ARDS), and death. Seroma formation has been recently demonstrated to be more frequent in overweight or obese patients. ^[17]

A study by Sieffert et al indicated that compared with nonobese patients, obese patients who undergo outpatient plastic surgery procedures, such as liposuction, more frequently have serious adverse events and a need for hospital-based acute care, within 30 days following the operation. The study found, for example, that among obese patients who underwent liposuction, adjusted hospital charges within 30 days after the procedure were $3917 higher, on average, than those of nonobese patients. The study looked at 47,741 discharges for liposuction, abdominoplasty, breast reduction, and blepharoplasty, with patients in 2052 of these discharges being obese. ^[18]

A retrospective study by Saad et al indicated that when abdominoplasty and liposuction are performed concurrently, the venous thromboembolism rate at 30 days and 1 year postoperatively is greater than the individual thromboembolism rates for the two procedures combined. Specifically, the individual 1-year thromboembolism rates for abdominoplasty and liposuction are 0.57% and 0.20%, according to the investigators, while the 1-year rate when the procedures are performed at the same time is 0.81%. ^[19]

A study by Kaoutzanis et al also indicated that the risk of major complications is greater when liposuction is performed in combination with other aesthetic procedures. Performed by itself, liposuction had a major complication rate of 0.7%, the most common complications being hematoma (0.15%), pulmonary complications (0.1%), infection (0.1%), and confirmed venous thromboembolism (0.06%). Performed with other procedures, the relative risk for major complications was 4.81. ^[20]

A literature review by Kanapathy et al involving large-volume liposuction found the pooled overall incidence of major surgical complications associated with the procedure to be 3.35%. An average volume of 7734.90 mL was aspirated from each patient in the study, with major complications including, in order of frequency, blood loss requiring transfusion (2.89%), pulmonary embolism (0.18%), hematoma (0.16%), necrotizing fasciitis (0.13%), and deep vein thrombosis (0.12%). Minor surgical complications had a pooled overall incidence of 11.62%, the commonest one being seroma (5.51%). ^[21]

Media attention has focused on patient deaths after large-volume liposuction. Studies indicate mortality rates of approximately 20 per 100,000, with pulmonary thromboembolism and fluid imbalances the major causes of mortality (23%). Review of major and lethal complications demonstrate major risk factors resulting from insufficient hygiene standards, infiltration of multiple liters of wetting solutions, permissive postoperative discharge, selection of inappropriate patients, and lack of surgical experience. These same authors also recommend the evaluation of patients the day after surgery to assess for major complications, as almost 80% of major complications were clinically evident within that time frame. ^[22]

Since initial descriptions of fat removal with curettes and suction, technical advances with the development of blunt-tipped cannulas, cross-tunneling techniques through multiple ports, the tumescent technique, and inpatient postoperative observation for patients undergoing aspiration of >5 L have resulted in lower complication rates and improved cosmetic outcomes.

Outcome studies have shown that 80% of patients were satisfied with their liposuction results and 53% rated their appearance as excellent or very good. ^[23] Similarly, a questionnaire study by Papadopulos et al found that 6 months after undergoing aesthetic liposuction, patients demonstrated high satisfaction with the procedure’s results, with significant improvement found in the quality of life in general, as well as in health, body image, and emotional stability. Individuals also experienced reduced anxiety. ^[24]

A study by Broughton et al found that following liposuction, three-quarters of patients rated postoperative discomfort as mild to moderate, with 60% indicating that pain persisted for less than a week. ^[23]

Interestingly, weight gain is common after liposuction and is seen in 43% of patients, with the abdomen serving as the most common location of recurrence. ^[23]