Liposuction: a comprehensive review of techniques and safety

Basic science and anatomic considerations

Anatomy texts divide subcutaneous fat throughout the body into superficial and deep layers or compartments separated by Scarpa's fascia, or the superficial fascial system. However, for the purposes of liposuction and body contouring, subcutaneous fat is arbitrarily divided into three layers: superficial, intermediate, and deep ( Fig. 25.2.1 ). The importance of this distinction is that the superficial layer is one that should be approached with caution and by those with a strong foundation and experience in liposuction. If this layer is treated, there may be vascular compromise and/or a significantly increased risk for contour irregularities. The relative consistency and thickness of each of these separate layers varies for different anatomic areas. For example, the fat of the back has a more fibrous, compact superficial and intermediate layer, with an underlying loose, areolar layer. This contrasts with the fat of the inner thigh, which is not as fibrous and is less compact. This is critical information for the aesthetic surgeon in order to perform safe and appropriate suctioning of the targeted area, while minimizing potential contour irregularities and skin necrosis. The variation in fat consistency and depth will be discussed further, as it relates to safe suctioning techniques and the choice of modality for the most effective treatment.

Anatomic “zones of adherence”, which are present in both men and women, are important to identify and note during the preoperative consultation. These are areas of relatively dense fibrous attachments to underlying deep fascia, which help define the natural shape and curve of the body. There are gender-specific variations with respect to each of these zones ( Fig. 25.2.2 ). It is important to recognize these zones, as they are identified as high-risk areas for contour irregularities after surgical intervention if not properly respected. However, these are not areas to avoid in all cases and, on occasion, help guide the surgeon in establishing “contour goals” for surgical intervention. Regardless of the tool used for liposuction, it is helpful to consider the treatment area in terms of the three surgical layers. These arbitrary layers help delineate areas of safety when performing liposuction. The most common areas treated are the intermediate and deep layer. Treatment of these layers allows uniform reduction without risk of injury to the subdermal plexus and unwanted skin injury.

Classification

It is helpful to classify patients based on the three types of lipodystrophy and skin redundancy ( Fig. 25.2.3 ):

• Type I: localized lipodystrophy . Often younger patients with good skin tone and minimal skin irregularities.

• Type II: generalized lipodystrophy . These patients tend to have slightly diminished skin tone with some skin irregularities and circumferential lipodystrophy throughout their trunk and extremities.

• Type III: skin redundancy and lipodystrophy . Patients displaying significant skin redundancy that would be more amenable to excisional surgical techniques to improve shape and contour. If necessary, liposuction may be a useful adjunct in order to achieve an optimal result.

Cellulite is a skin condition that is often seen when evaluating patients for liposuction. Cellulite is a dimpling of the skin, particularly in the areas of thighs and buttocks. It has a poorly understood pathophysiology but is thought to be related to fibrous, dermal attachments to the underlying fascia and surrounding hypertrophied fat. It has a hormonally mediated component. A range of surgical and non-surgical techniques have been described for treatment of cellulite, all with the similar goal of disrupting the fibrous septae that separate the fat. These have ranged from liposuction with aggressive cannulas with fat grafting, 1440-nm pulsed laser, needle or blade subcision release, and more recently, injection of collagenase. There is no high level evidence comparing the efficacy of these techniques. Any provider should carefully approach the treatment of this difficult pathophysiology. This should be clearly delineated to the patient as the goals of surgery are reviewed.

Diagnosis, operative indications, and patient selection

Liposuction patients often present with a variety of expectations, concerns, and/or complaints. In order to achieve optimal contour with liposuction, appropriate patient selection is imperative. As a general rule, liposuction is performed in healthy patients who maintain realistic goals and expectations. Studies have shown that patients who undergo proper long-term lifestyle changes will in fact achieve the highest level of postoperative satisfaction from their liposuction-assisted body contouring procedure. Rohrich et al . concluded that those patients who were committed to a positive lifestyle change involving a healthy diet and regular exercise, or who were already practicing a “healthy lifestyle” that continued postoperatively, experienced the best self-assessment and satisfaction scores with liposuction postoperatively ( Fig. 25.2.4 ). A successful body contouring patient must satisfy four key elements to achieve and maintain optimal results:

• 1.

  Lifestyle change.

• 2.

  Regular exercise.

• 3.

  Well-balanced diet.

• 4.

  Body contouring.

Appropriate candidates for liposuction are not morbidly obese, are of a stable weight, and have incorporated the above lifestyle changes into their preoperative regimen. It is preferable for patients to commit to the necessary changes in diet, exercise, and lifestyle modification before undergoing surgery. It is the responsibility of the surgeon to address all concerns, expectations, and goals prior to the procedure in order to establish realistic expectations of the procedure to the patient. Preoperative consultation with a dietician may prove beneficial for long-term patient satisfaction. Liposuction is contraindicated in patients who are pregnant or in poor general medical health. Patients with morbid obesity, cardiopulmonary disease, body image perception issues, unrealistic expectations, wound healing difficulties, or who have extensive or poorly located scars should be excluded from consideration for liposuction.

Preoperative assessment

Physical exam

A detailed physical exam is performed at the first visit and consultation. Specific attention to skin quality, prior scars, presence or absence of hernias, evidence of venous insufficiency, and presence of pre-existing asymmetry or contour irregularity should be discussed and noted in the chart. At the initial and subsequent visits, height and weight with calculation of body mass index (BMI) is paramount for safety, as well as for observation of long-term trends during follow-up. For liposuction candidates, six key elements are documented:

• 1.

  Evaluation of areas of lipodystrophy and contour deformities.

• 2.

  Skin tone and quality.

• 3.

  Asymmetries.

• 4.

  Dimpling and cellulite.

• 5.

  Myofascial support/presence of hernia(s).

• 6.

  Zones of adherence.

The physical exam begins in front of a full-length mirror ( Fig. 25.2.5 ). This allows an open dialogue between patient and physician, wherein the patient's concerns can be addressed and previously unrecognized problem areas can be assessed and addressed. Any areas of cellulite should be pointed out to the patient, and a specific discussion of expected outcome in these areas should be noted. While the patient is in a supine position with the head elevated, abdominal integrity is examined ( Fig. 25.2.6 ). This is helpful for detecting hernias or myofascial diastases. Findings may be difficult to interpret in larger individuals, males, or patients with multiple scars. An ultrasound examination or computed tomography (CT) scan may further clarify this region and prevent potential intra-abdominal injury in these challenging patients. During the initial consultation, when the patient is in front of the mirror, it is important to point out potential problem areas that may cause less than optimal results, so the patient may visualize and appreciate these areas.

At the initial evaluation, high-quality medical images should be obtained, with anterior, posterior, lateral, and oblique views. This will allow for documentation of results, as well as objective evaluation of outcomes by both patient and physician. Professional medical photography can be a very useful tool for accurate and consistent pre- and postoperative documentation. If superficial liposuction or “liposculpture” is planned, a detailed exam of the subcutaneous fat distribution is essential. Attention must be paid to “gender ideal” muscular shape, mass, and fat distribution. Additionally, dynamic areas must be examined and marked in the full range of muscular contraction to yield natural results. Inattention to these details may result in unnatural appearances and contour irregularities.

A follow-up visit is typically scheduled 2–3 weeks after the initial consultation. During this visit, computer images ( Fig. 25.2.7 ) are potentially reviewed, which allows the patient to establish realistic expectations. These objective images portray the advantages, disadvantages, and limitations of body contouring surgery. The patient should understand that imaging is for educational purposes only and is not a guarantee of the final result. The second visit allows further dialogue between the patient and physician so that all questions may be answered and issues addressed. For example, a second opportunity to address any last minute concerns by the patient in regard to recovery time, pain control, bruising, and postoperative changes will help strengthen the patient's confidence in the procedure and decrease the likelihood of any uncertainties or surprises within the perioperative period. The second visit may be structured in a HIPAA (Health Insurance Portability and Accountability Act) compliant, virtual consultation setting for patient convenience.

Preoperative marking

Guiding marks are performed prior to surgery with the patient in the standing, upright position. In patients undergoing total body liposuction or contouring in combination with excisional surgery and/or fat transfer, marking can be done in the office the day before surgery. This allows for a more private environment and ample time to review the plan with the patient including review of preoperative markings and photos. Marking is done in front of a mirror, thus allowing the patient to contribute to the process, and further confirms exactly what will be addressed during the procedure. Areas to be suctioned are marked with a circle; zones of adherence and areas to avoid are marked with hash marks. Asymmetries, cellulite, and dimpling are marked for their respective treatment and to allow patients to see problem areas highlighted. When complete, the marks are once again reviewed with the patient to ensure that all areas of concern are addressed. Access incisions are also marked at this setting. Often two incisions are needed per area to be treated; these incisions should be placed adjacent to suctioned areas and not too distant. With liposuction, it is beneficial to choose access points that can treat multiple areas when possible. That being said, incisions are small and typically heal well so should be utilized liberally to achieve cross-hatching of the area and an ability to contour from multiple sites, allowing for more uniform reduction and decreasing the risk for access site depression. Care should be taken to prevent access incision placement in or adjacent to zones of adherence. The suctioning may cross the zone and disrupt it. Incisions should also allow each area to be treated from different directions for optimal contouring. Incisions should be no longer than 3–5 mm in length and placed in well-concealed areas. The surgeon should not hesitate to place additional incisions if access is insufficient with the existing markings. The use of skin protectors is preferred to prevent friction induced thermal injury to the skin and subcutaneous fat at the cannula access port location.

Fig. 25.2.8 shows the preoperative markings and preferred placement of access incisions based on areas to be suctioned. Cosmetically, it is preferable to stagger incisions in an asymmetric fashion to camouflage their appearance.

Anesthesia and location of operation

It is up to the surgeon to determine the optimal surgical setting for each patient undergoing liposuction. Factors that influence this decision are the amount of expected lipoaspirate, length and extent of procedure, patient positioning, operating surgeon preference, anesthesiologist preference, and overall health of the patient. Depending on the geographical location, there are differing regulations for the location of liposuction procedures, usually based on the type of anesthesia and the area or total lipoaspirate volume of the liposuction procedure. For example, one recommendation is to avoid epidural and spinal anesthesia in office-based settings because of potential hypotension and volume overload issues.

As a general rule, small-volume liposuction cases can be performed with local anesthesia, with or without mild sedation. Complex, large-volume liposuction and combined cases should be performed under general anesthesia or regional block. Our institutional preference has been to perform liposuction cases under general anesthesia. Deep-sedation cases and general anesthesia procedures are performed under supervision of board-certified anesthesiologists in licensed surgery centers or hospitals. All cases are performed with general endotracheal anesthesia for airway control and patient paralysis to permit predictable patient position while cannulas are in movement. Operative location should be determined after careful patient evaluation, assessment of the complexity of operation, and appropriate evaluation of medical comorbidities. The anticipated postoperative course and the need for possible overnight observation both factor into choice between inpatient observation or outpatient hospital settings.

Awake liposuction has been performed in the office-based setting with a tumescent technique. The authors prefer to do such procedures only for single area treatments or in small revisions. Detailed patient assessment and strict limitations on volumes infiltrated and amount of lipoaspirate expected should be reviewed prior to performing in an unmonitored office-based setting; this should be approached with caution and the patient's safety kept in mind.

Special importance should be given to medical comorbidities such as obstructive sleep apnea. American Society of Anesthesiology recommendations include the following: for patients with signs or symptoms suggestive of moderate to severe obstructive sleep apnea, surgery should be performed in a hospital setting with extended recovery and observation to prevent postoperative respiratory complications, including postoperative respiratory failure. It is recommended that liposuction procedures, whether inpatient or outpatient, if under anesthesia care, should be performed in an accredited facility with the capability to manage any postoperative problems with a board-certified anesthesiologist present as part of the care team. During the liposuction procedure, it is useful to have the circulating nurse maintain an accurate liposuction data sheet to facilitate consistent and accurate communication between the surgeon, the anesthesiologist, and the operating room team.

Maintaining core body temperature and immediate preoperative care

The patient is placed in a forced air warming blanket 30–60 min prior to the procedure in the preoperative holding area. Additionally, pedal or calf compression devices are also applied in the holding area. This should be instituted as part of preoperative orders to assist in DVT prophylaxis and prevent the patient becoming cold during the procedure. During the procedure, all areas not being treated should be covered by the forced warm air blanket. The wetting solutions should be warmed and not administered cold. Additionally, warmed intravenous resuscitative fluids can be administered for longer procedures that contribute greater risk secondary from prolonged patient exposure to ambient operating room temperatures and anesthesia.

Patient positioning

Prone/supine

Once marked, the patient position is determined. The cadence of the operation usually begins with the patient in the prone position followed by supine. This necessitates prepping and draping the patient twice. If the team works together, turnaround time should be limited to less than 10 min. An alternative method is to prep the patient circumferentially while standing and to then position the patient on a sterile table with position changes not necessitating a reprep. We dislike this technique as it may be embarrassing for the patient and increases the likelihood of hypothermia. Once in the operating room, the compression devices already applied to the patient are reconnected before being placed under general anesthesia. In the majority of our liposuction cases, we prefer to position the patient prone first. A soft hip roll is placed beneath the iliac crests to elevate the treatment areas off the bed, and either pillows or longitudinal rolls are used to support the upper chest after the induction of anesthesia in a prone position on the adjacent preoperative stretcher ( Fig. 25.2.9 ). The breasts should be placed medially and nipples protected.

The patient's arms are carefully placed on padded arm boards with elbows bent and hands forward with the elbow below the level of the axilla to decrease potential positional risk injury such as direct pressure injury or nerve stretch injury. The face must be appropriately padded, including placing the cervical spine in a neutral position and protecting the globes. Patients in the prone position are subjected to pressure changes over the forehead, malar areas, iliac crest, and bony prominences of the arms and legs. Special attention also needs to be given to the female and male genitals. In the prone position, up to 70% of the contouring can be performed and may include liposuction of the arms, back, hips/flanks, lateral, posterior, and medial thighs.

With the patient in the supine position, the remainder of the trunk and extremities can be addressed. This may include treatment of the chest, arms, abdomen, anterior medial thighs, and knees. The hips and knees should be flexed at approximately 30° with a pillow. Pressure points in the supine position include the occiput, scapula, posterior iliac crest, sacrum, and heels. Regardless of prone or supine position, careful attention should be paid to pressure points, maintaining joints with normal range of motion, and adequate coverage of patient with warming devices or blankets.