Liposuction 

• Anatomy: There are several different layers of subcutaneous fat, which becomes important when discussing liposuction. There is the superficial layer, the intermediate layer, and the deep layer. 
• The first layer is the superficial layer which contains dense fat adherent to overlying skin. This region is usually avoided to prevent contour irregularities. The next layer is the intermediate layer. This is the safest layer to perform liposuction. The deep layer is loose and less compact fat and can be removed safely in most areas except the buttock.  

• Cellulite, or gynoid lipodystrophy, is caused by hypertrophy of the superficial fat within the setpa that connects the superficial fascia system and the dermis.  
• The next concept is zones of adherence, which is important to remember when considering liposuction. These zones should not be violated during liposuction as they will result in contour irregularities. The zones of adherence are the distal iliotibial tract, the gluteal crease, the lateral gluteal depression ,the middle medial thigh, and the distal posterior thigh.  
• About Liposuction: Typically, liposuction cannulas are made in different lengths and widths, blunt vs sharp. The overall general principle is that blunt tipped cannulas carry less of a risk of injuring important neurovascular structures or fascia, and the smaller the diameter of the cannula will lend itself to more even fat removal.  
• Wetting Solutions: Wetting solutions are frequently tested on inservice examinations. These include dry, wet, superwet and tumescent. Dry liposuction does not offer any infiltrate and will generally have a greater blood loss of up to 50%. Wet is 200-300mL of infiltrate regardless of what is removed and carries a 3-10% blood loss of total infiltrate. Superwet is a 1:1 ratio of infiltrate to amount of aspirate and carries a 1% blood loss rate. Tumescent is 2-3:1 infiltrate to aspirate and carries <1% blood loss.  
• Wetting solutions provide volume replacement, hemostasis, pain control and can include lactated ringers, lidocaine and epinephrine. The general makeup is 1L of LR for 30-5-mL of 1% lidocaine and 1mL of 1:1000 epinephrine.  

• Infiltration may provide up to 18 hours of analgesia. The maximum dose of lidocaine is 35-55mg/kg resulting in peak levels at 12 hours post op. The ability to provide higher amounts without toxicity is due to the diluted solution, slow infiltration, high solubility, and relative vasocontrictive effect of epinephrine.  
• Remember, 10-30% of lidocaine is aspirated with liposuction. 
• Indications: Indications for suction lipectomy include lipodystrophy, HIV lipodystrophy, madelungs, axillary hyperhydrosis, lymphedema.  
• Techniques: 
• UAL: Ultrasound Assisted Liposuction emulsifies subcutaneous fat by three processes micromechanical (direct trauma by ultransonic wave), thermal, and cavitation (tissue fragmentation). Suction lipectomy is then used for evacuation. The process usually includes infiltration, ultrasonic treatment for emulsification of fat, followed by evacuation and final contouring. Complications include risk of thermal injury, seroma, neuropraxia, and hyperpigmentation.  

• Power Assisted Liposuction: This is the most common type of liposuction employed and involves infiltration, and evacuation with externally powered oscillating cannula. This technique is able to perform aspiration of larger volumes and fibrous areas.  
• Laser Assisted Liposuction: The mechanism of action of  includes disrupting fat cell membranes and emulsifying fat. It begins by infiltration, application of laser, suction lipectomy through traditional techniques and subdermal skin stimulation. The heating of subdermal tissue is thought to be the main factor for the skin tightening effect. This technique is known to have a decrease in post operative pain. 
• Safety Considerations:  
• Fluid resuscitation should include 2:1 with 2x the amount of resuscitation for each ML aspirated. This should include the infiltration and IVF. 
• Lidocaine infiltration should not exceed 35m/kg 

• Large volume liposuction (>5L) should be performed at the appropriate health care facility, without simultaneous procedures, include overnight monitoring, and include MIVF along with infiltration.  
• If local anesthetic toxicity is suspected, infusion of 20% lipid emulsion should occur.  
• Suction lipectomy rarely transects vessels, usually causes neuropraxia, observe for deficits > 3 months 
• PE most common cause of death in suction lipectomy 
• Irregularities in liposuction are usually due to large cannula, superficial tunneling and a single port.  

• Contour deformity is the most common complication.  

Abdominoplasty: 

• Anatomy: The abdominal wall has seven layers and includes skin, subcutaneous fat, scarpas fascia, subscarpal fat, anterior rectus sheath (above the arcuate line) muscle, and posterior rectus sheath. Remember from liposuction that the abdominal wall has separate layers of fat separated by scarpas fascia. Thinning of the superficial layer of fat during an abdominoplasty is a risk factor for skin compromise.  
• Remember, above the arcuate line there is a anterior and posterior rectus sheath consisting of fascial contributions from external and internal oblique (anterior rectus sheath) and internal oblique and transverse abdominus (posterior rectus sheath. Below the arcuate line these contributions form an anterior rectus sheath only with no posterior rectus sheath. 
• The blood supply of the abdomen in separated by zones. Zone 1 consists of the superior and inferior epigastric system, zone 2 the circumflex iliac and external pudendal systems, and zone 3 the intercostals and external pudendal system. Zone 1 is primarily mid abdomen overlying the rectus, zone 2 is between the ASIS and inguinal crease and zone 3 is is lateral and superior to zone II 

• There are several nerves to be aware of in abdominoplasty.  The lateral femoral cutaneous nerve innervates the skin of the lateral aspect of the thigh and emerges close to the ASIS. This may be inadvertently injured during abdominoplasty and is prevented by leaving a layer of fat over the ASIS. Innervation to the muscles comes from t7-t12 and travels between the internal oblique and transversus muscles. Nerves at risk for injury during abdominoplasty, ilioinguinal, iliohypogastric, intercostal. Lateral femoral cutaneous supplies lateral thigh (above ASIS); genitofemoral nerve supplies pubis; iliohypogastric (lateral buttocks, lateral mons); ilioinguinal (mons); obturator (medial thigh) 
• The umbilicus is important in abdominoplasty for both location and shape. It is typically located near the level of the iliac crest in the midline. Pleasing characteristics include a shallow umbilicus that has superior hooding, inferior retraction and a round shape. The blood supply is important to maintain and includes the subdermal plexus, the inferior epigastrics, the ligamentum teres, and median umbilical ligament. 
• There are differences in aging between men and women. Typically: men have > upper rectus diastasis than women, intrabdominal accumulation of fat, accumulation of fat centrally below iliac crest, less skin laxity, and less tendency for striation 
• Patient Evaluation: It is important to obtain a full history from a patient seeking abdominoplasty. Pertinent positives include children, c-section, hernias, previous abdominal surgery, smoking status.  
• Physical examination is important to note skin laxity (in both horizontal and vertical directions), striae, rashes, scars from previous surgery, fascial laxity, hernias. Upper midline scars may limit movement of flap, while subcostal scars represent an interruption to the superolateral blood supply.Epigastrics disrupted in abdominoplasty and rely on intercostals which can be interrupted in subcostal incision). Abdominoplasty in these patients may inadvertently cause wound healing issues due to interruptions of blood supply. If abdominoplasty is performed, it is important to not undermine beneath these incisions. Diastasis is typically an indication for plication during abdominoplasty and is noted as a bulge that decreases when lying down. 

• Complications: In general the complication rate can be as high as 34%. Wound healing complications alone are 14% and increase to 50% in smokers. Infra umbilical and supraumbilical abdomen has the highest incidence of wound healing issues. Skin necrosis occurs at suprapubic region due to lateral interstitial vessels. Remember, complications in abdominoplasty occur more often in those with BMI >30. 
•  Other risks include malposition or death of the umbilicus, seroma (which is the most common complication of abdominoplasty when performed alone, venothromboembolism (higher than any other cosmetic procedure), and infection. In the case of painful neuroma- treatment may consist of lidocaine injection for diagnosis followed by CSI and resection and reimplantaiton if the patient remains symptomatic. 
• Current guidelines for VTE prophylaxis include chemical prophylaxis for those with caprini score >7. Lovenox 40mg should be given 6-8 hours after the procedure and for the duration of the hospital stay. VTE risk during abdominoplasty is 8%. 
• Current SCIP (surgical care improvement project) recommends no shaving and no using of razors, IV antibiotics 30-59 minutes prior to incision, post operative antibiotics for 24 hours, no elective surgery if A1c >7, and prevention of intraoperative hypothermia. 
• Procedures:  

• There are several different procedures that are indicated for differing conditions. It is important to take into account the amount, location, and direction of skin laxity when choosing the best procedure for your patient. Here, we will talk about the three most common types of abdominoplasty: the traditional abdominoplasty, the miniabdominoplasy, and the fleur de lis abdominoplasty. Remember that there are many other variations that exist.  
• Traditional abdominoplasty is indicated for those that have significant amounts of skin and fat not limited to the infraumbilical region. This is a combination of liposuction abdominoplasty. 

• Planned incision is marked at the level of the pubic bone and must be 5-7cm above the top of the vulvar commissure. A pinch test is then performed to determine how much skin can be resected (typically just slightly above the level of the umbilicus). 
• In general, the umbilicus is incised and separated down to the rectus sheath, taking care not to skeletonize the umbilical stalk which may comprise its vascularity. The inferior incisions are made and the flaps are raised above the level of the rectus and oblique fascia. This may be raised in the areolar plane or with a small layer of subcutaneous fat left in place. These flaps are raised above the umbilicus and then with discontinuous undermining to the costal margins laterally and the xiphoid process medially. Remember to leave a small amount of fat above the level of the ASIS to protect the lateral femoral cutaneous nerves. Rectus plication is then performed, and the patient is placed in beach chair position to remove the abdominal flap and perform a tension free closure. Rectus plication is performed in both vertical and horizontal planes and utilizes permanent suture.  
• Upon closure, progressive tension sutures may be used to distribute tension. These are placed from scarpas to abdominal wall fascia sequentially. This decreases tension, prevents hematomas and seromas, decreases necrosis and hypertrophic scaring.  

• The new position of the umbilicus is determined (based on iliac crest) and is transposed and inset. Drains are typically used and the incision is closed in layers.  

• Miniabdominoplasty: The miniabdominoplasty is useful fore patients with primarily infraumbilical excess of skin and fat. This utilizes a shorter transverse scar and does not separate the umbilicus from the abdominal wall flap. Instead, the umbilical stalk is transected, the fascial defect repaired, plication performed, and conservative abdominal flap removed. Keep in mind that this will move the umbilicus inferiorly.  
• Fleur-de-lis abdominoplasty: This technique allows for excision of excess skin in both horizontal and vertical directions. It includes a trasnverse incision at the level of the pubis as well as a mdiline incision that may go as superiorly as the xiphoid process. Take care not to underline past what will be contained within the excision.  

• Combined Procedures: Recent Grotting data for reported complications.  

• Multiple combined body contouring procedures- wound dehiscence most common followed by seroma 

• Abdominoplasty combined with liposuction – 3.8% 
• Abdominoplasty combined with a breast procedure – 4.3% 
• Abdominoplasty combined with a breast procedure and liposuction – 4.6% 
• Abdominoplasty combined with liposuction and a body contouring procedure – 10.4% 
• Abdominoplasty combined with liposuction, a breast procedure, and a body procedure – 12.0%