ABDOMINOPLASTY

 The abdominoplasty is commonly referred to as a “tummy tuck”.  But what is this class of procedures which so easily rolls off the tongue?  This group of procedures is designed to remove excess skin and fat from the abdomen.  The abdominal skin can be stretched by pregnancy or major weight gain, resulting in loss of skin and muscle elasticity or “tone”.   Unfortunately, skin tone cannot be improved with exercise.   Pregnancy can separate the rectus abdominus muscles; this “diastasis” will not improve with exercise.  This article will discuss the general surgical principles and issues related to abdominoplasty.  When skin tone is adequate, and the abdominal musculature has not been overstretched, then liposuction is the best approach to remove fat that is resistant to dietary efforts.  Liposuction results in much smaller scars, the risks are less, and the recovery is easier.
 Abdominoplasty is a significant operation, and it should not be undertaken unless the procedure, the recovery, and all of the risks are understood and weighed.  The location and degree of the looseness, the patient’s age, size, and presence of “stretch marks” help to determine the best choice of procedures for improvement. The operation is planned, and incisions are usually marked in ink, prior to entering the operating room.  The usual first incision extends all the way across the lower abdomen, and it is just above the pubic hair in the midline (figure 1).  The length of this incision is proportional to the amount of loose skin to be removed.  This incision is carried down to the fascia overlying the abdominal musculature.  A second incision is placed around the umbilicus.  The umbilicus is left attached to the abdominal wall by a stalk of fatty tissue.  Dissection is then carried upward from the first incision, staying above the muscle fascia, all the way to the area of the rib cage.  The abdominal skin and fat can then be lifted away from the muscles of the abdominal wall.  The rectus abdominus muscles are then sutured together from xiphoid to pubis with permanent sutures in the midline to tighten the muscular wall, repair any diastasis or hernia between the muscles, flatten the abdomen, and shorten the waistline (figure 2).  The operating table is then flexed (approximately 45 degrees) at the patient’s hips, to allow excision of as much excess tissue as feasible.  The large loose flap of skin and fat is then pulled inferiorly to assess how much skin and fat can be safely removed.  The preoperative evaluation in this regard is also considered.  An incision is marked and placed across the abdomen (figure 3) to remove excess skin and fat.  (This is the third incision.)  It is often possible to remove the site where the umbilicus    had     been located.  This means that all of the superficial tissue below the umbilicus has been removed, using a large football-shaped excision.  A new hole must be created for the umbilicus.  The wounds are then sutured closed across the lower abdomen and around the umbilicus (figure 4). The closure of a wound of this shape is expected to result in a mound of skin and tissue, or “dart” just beyond each end of the large transverse suture line.  These mounds of tissue could detract from the appearance of the hips, but this can usually be minimized with liposuction at this site.  However, liposuction of the flap itself can compromise vascularity to the flap.  Thus, significant excess adiposity may remain after abdominoplasty in some cases.  This can be addressed by liposuction at a later, second procedure.  Tubular drains are usually placed within the cavity.  The drains come out through the skin in the pubic area.  Squeeze bulbs at the ends of the drains will contain fluid that usually comes from the wound. The drains are removed when the amount of fluid coming from the wound has decreased adequately (several days). Patients are taught to care for the drains and measure the fluid produced.   The drain sites should not be submerged in water until these sites have closed.
 Although there are a number of variations with regard to incision placement and technique, certain generalizations can be made regarding the recovery process.  Since the wound closure is under some tension, a supportive abdominal binder is worn, except during bathing, for the first few postoperative weeks.  Bringing the knees toward the chest, or even sitting normally, can cause the abdominal flap to fold, which creates a space for fluid accumulation.  Such fluid accumulation, termed a seroma, is not uncommon after abdominoplasty, and it requires percutaneous needle drainage two or three times per week for several weeks.  
 Abdominal skin and fat are not highly vascular.  When this tissue is    undermined and placed underundermined and placed under tension, circulatory compromise can occur.  The skin in the midline, just above the transverse repair, is most susceptible to necrosis.  It is important that the patient does not stand fully upright during the earlier stages of healing, as this may place too much tension on the skin, causing the wound to open or leading to avascular necrosis.  Again, this complication is not rare, but after several weeks of wound care, it generally heals adequately (although the scar will be wider in the affected area.)  The hypovascular area just above the incision line, and the umbilical inset area, is also susceptible to infection, and minor infections in these areas are also not rare.  Fortunately, major invasive infections are very uncommon.
 Despite plastic surgical techniques, the scars resulting from abdominoplasty tend to widen in the weeks and months following the procedure.  This is at least partly due to the tension resulting from skin excision.  If a patient is known to form scars that are more unsightly than an average person, consideration must be given to this issue prior to the operation.
 Other issues and complications can follow this significant operation.  Abdominoplasty does not necessarily produce an ideal abdominal contour, and it is occasionally followed by a “touch-up” procedure after healing, in order to obtain the best possible result.  The amount of adipose tissue removed generally does not weigh as much as the patient might guess.  Good hemostasis is obtained during surgery, yet occasionally bleeding occurs after the surgery is completed, requiring a return to the operating room.  Because cutaneous nerves are transected as part of the procedure, it is expected that sensation of the lower abdominal area will be diminished.  This paresthesia is considered a usual side effect of abdominoplasty.  In some cases, neuromas can form, resulting in painful dysesthesias.  However, most patients are not unduly troubled even when this occurs, as the area involved is not frequently stimulated.
Abdominal muscle straining or exercise in the first six weeks could compromise the muscle and fascia repair.  The muscle repair can also be disrupted by subsequent pregnancy or major weight gain.  Thus, it is important that the patient’s weight will remain reasonably stable after surgery; pregnancy would make the abdomen appear worse than prior to the operation.  Tenderness along the muscle repair is expected, at least for a few months.  The abdominal wall feels tight and stiff for at least several months.  It is rare for tightness and tenderness to be permanent.
In addition to the above, because abdominoplasty is a significant operation, systemic medical complications can occur.  Soreness of the operated area is expected, but this operation is generally not as painful as one might guess, given all of the dissection.  Nonetheless, it is painful to cough and clear secretions in the early postoperative period.  A tendency not to cough must be resisted, as failure to keep secretions from going down the trachea could result in pneumonia.
Blood clots can form in the legs (venous thromboses), and these clots can break loose from the legs and go to the lungs (pulmonary embolism).  Special stockings are usually applied during surgery to help prevent this potentially life-threatening complication.  And it is very important that the patients get out of bed and begin ambulation within a day of surgery.  Patients with additional risk factors for blood clots may not be candidates for this surgery.
The benefits of abdominoplasty can be dramatic and long lasting, and after the healing period patients are usually quite happy that they underwent the procedure.  Naturally, informed consent involving the issues in this article is necessary.

Legends:
Figure 1.  Note the initial incisions (red).  Undermining on top of abdominal fascia (pink) allows mobilization of loose skin and fat.

Figure 2.  The umbilicus is left attached to the abdominal muscular wall.  Rectus abdominus muscles are sutured together securely, inverting the closure line inward.

Figure 3.  The skin, attached to underlying fat, forms a loose flap that is pulled downward.  The excess skin and fat is excised, often including the prior umbilical site.

Figure 4.  The wound closures result in a scar around the umbilicus and a low scar across the abdomen.