Fat Embolism Syndrome (FES)

There is still confusion regarding fat embolism (FE) and fat embolism syndrome (FES). FES is a phenomenon secondary to FE. Hence, FES is a more accurate term regarding complications after liposuction, because the patient suffers a cascade of symptoms. The incidence of FES in liposuction is currently unknown.

The classic triad includes respiratory distress, cerebral dysfunction, and petechial rash. Other signs and symptoms include thrombocytopenia, anemia, tachycardia, hypocalcemia, and fever.

Diagnosis using ventilation–perfusion scan may show the matching defects.^6–8 Differential diagnoses include fluid overload, pulmonary edema, aspiration pneumonia and various other causes of acute respiratory distress syndrome (ARDS).⁹ Most of all, differentiation of FES from pulmonary embolism is important because the treatment is very different. Heparin can be harmful, for obvious reasons, in the early management of FES.

There are no definite preventive measures for FES. However, using small caliber cannulae and serial suction rather than megaliposuction is generally recommended.

Treatments using intravenous ethanol, heparin, and low molecular weight dextran have largely fallen from favor. Medical management now consists mainly of high-dose corticosteroids, which have been shown to prevent the development of FES in several prospective randomized trials.^10–12 The role of corticosteroids is considered to inhibit the inflammatory reaction to the presence of fat in the circulatory system after liposuction.

Deep Vein Thrombosis (DVT) and Pulmonary Embolism (PE)

There are three major factors that are important in the development of DVT and PE. The first is the development of venous stasis, the second is the activation of a blood coagulation cascade, and the third is injury to the vascular endothelium (Virchow’s triad).¹³

Preoperative and early postoperative ambulation is crucial for preventing this event. Epidural anesthesia will increase blood flow to the lower extremity, lessen stagnant blood flow, and may reduce thrombotic complications. Shortening the anesthesia time may be beneficial; hence serial liposuction rather than large volume liposuction is recommended. Compression garments to the ankles avoid a tourniquet effect at the knee.

For high-risk patients, intermittent pneumatic pressure devices rather than continuous devices may be beneficial. Low-dose subcutaneous heparin (2500 U every 12 hours, beginning 2 hours preoperatively) may further reduce the incidence of DVT but it should be remembered that it can also simultaneously increase the risk of bleeding. For most practitioners, fractionated heparin appears preferable to unfractionated heparin.

Initial therapy consists of intravenous heparin, usually by a bolus dose of 5000 to 10 000 U.

A heparin drip at approximately 1000 U/h is then titrated to maintain an activated partial thromboplastin time (aPTT) of approximately twice the normal length. This necessitates hospitalization and frequent blood tests. Oral anticoagulant therapy with warfarin is usually initiated shortly thereafter and continued for a minimum of 6 weeks. Prothrombin time (PT) levels must be monitored during follow up to maintain an INR in the therapeutic range.

Extended Infection

Liposuction involves heavy manipulation of the superficial fascial system, resulting in the possibility of ascending infections via the fascial system, and there have been reports of necrotizing fasciitis from these procedures.¹⁴ Although infection in simple liposuction cases is rare, combined procedures including abdominoplasty and brachioplasty for reduced skin laxity may cause serious infections. Hematomas and seromas can become sources of infection, hence meticulous hemostasis and drainage of seromas is important to prevent infection (Figs 46.1 and 46.2). Moreover, maintaining aseptic techniques throughout the procedure is of utmost importance, especially during positional changes of the patient.

FIG. 46.1 Mycobacterium infection on right upper arm after liposuction procedure.

FIG. 46.2 Severe wound infection on right posterior thigh with a draining sinus.

(From Kim YH, et al. Analysis of postoperative complications for superficial liposuction: A review of 2398 cases. Plast Reconstr Surg 2011;127:863–871. with permission.)

Wound cultures should be obtained whenever possible and antibiotic treatment instituted according to sensitivities. Local drainage is recommended when necessary.

Hypovolemia/Anemia

Tumescent infiltration provides profound hemostasis in large volume liposuction.¹⁵ Bloodless aspiration virtually eliminates the possible sequelae of shock and hypovolemia. The ideal ratio of subcutaneous fluid to total aspirate is controversial. The surgeon must weigh the risks between excessive blood loss (inadequate subcutaneous fluid) and pulmonary edema (excess subcutaneous fluid). Fluid shifts between interstitial fluid and plasma volume can result in intravasation (hypervolemia) or extravasation (third spacing). Excessive infiltration obviously should be avoided. According to our 14-year experience with 2398 cases, the need for blood transfusions is rare. It must be remembered that 2000 ml aspiration of supernatant fat is regarded as a decrease in hemoglobin count by 1. Some of the drawbacks of blood transfusions include potential infection, transfusion mismatch, circulatory overload, microthrombi, and postoperative anemia.

Healthy normovolemic patients can tolerate a moderate reduction in hemoglobin count with multiple compensatory mechanisms. In clinical settings, normal tissue oxygenation is maintained with hematocrits as low as 20, if the subject is healthy and remains normovolemic.¹⁶

Lidocaine Toxicity

Early signs and symptoms of lidocaine toxicity include lightheadedness, restlessness, drowsiness, tinnitus, slurred speech, metallic taste in the mouth, and numbness of the lips and tongue. These subjective signs may be seen at plasma levels between 3 and 6 µg/ml. Shivering, muscle twitching, and tremors may occur as plasma levels reach 5–9 µg/ml, followed by convulsions, CNS depression, and then coma at plasma levels greater than 10 µg/ml. As levels increase above this, respiratory depression and eventually cardiac arrest can occur.¹⁷

Multiple variables add to patient risk. Conservative treatment is advised in patients taking oral contraceptives, beta blockers, and tricyclic antidepressants, because these medications increase serum lidocaine levels. In addition, hypovolemia, hypocalcemia, hypophosphatemia, and hypoalbuminemia may exacerbate the effects of lidocaine. Pre-existing liver disease slows lidocaine breakdown. Prevention of lidocaine toxicity begins with strict adherence to the currently accepted maximal recommended dose of 35 mg/kg. Early recognition of symptoms is important when they occur.

Treatments consist of hyperventilation and administration of benzodiazepines, which lower seizure threshold. The airway should be protected to prevent aspiration.

Contour Irregularities (Figs 46.3–46.7)

The most common complications of liposuction are undercorrection (insufficient fat removal), overcorrection (excessive fat removal), and irregular fat removal (with palpable and visible irregularities), which can be categorized as contour irregularities. From an esthetic viewpoint, postoperative contour irregularities can be devastating and decrease patient satisfaction dramatically.

FIG. 46.3 Contour irregularities on abdomen after superficial liposuction which were induced by too superficial suction.

FIG. 46.4 Severe sunken deformities on abdomen after conventional liposuction procedures which were caused by overzealous suctioning with a large caliber cannula. Hemosiderin procedures color deformity in tissues.

FIG. 46.5 Contour irregularities on lateral aspect of thigh with induction of fibrous and dense tissues.

FIG. 46.6 Severe contour irregularity at the trunk and thigh regions.

For correction of the problem, exact preoperative markings and the distinguishing of false and true depression is important.

(From Kim YH, et al. Analysis of postoperative complications for superficial liposuction: A review of 2398 cases. Plast Reconstr Surg 2011;127:863–871. with permission.)