Flap Reconstruction
Description
The operation is performed under general anesthetic, sometimes supplemented by
a paravertebral or epidural block. Adequate preoperative planning and preparation
is key to the success of TRAM fl ap breast reconstruction. Good lighting, careful
positioning, and high-quality equipment simplify the procedure.
Appropriate intravenous
antibiotics are given for 24 h or more. An island of skin and underlying
rectus Abdominis muscle is raised from the lower abdomen attached to its superior
vascular pedicle (superior epigastric vessels) and tunneled anteriorly to reach
the contralateral or sometimes the ipsilateral chest. Immediate TRAM fl ap breast
reconstruction (ITRAM) is carried out at the same time as mastectomy. It avoids the
need to recreate the breast pocket and re-dissect the medial axilla, which comprise
the initial steps of delayed TRAM fl ap breast reconstruction (DTRAM). Outcomes
are closely related to the accuracy of the preoperative markup. This should include
the position and size of the breast pocket, the exact extent of the fl ap harvest, and
the position of the anterior abdominal wall skin incisions. The markup is usually
performed prior to surgery with the patient standing up, rather than in the operating
theater. Some authors raise the unilateral pedicled fl ap for use immediately in
TRAM reconstruction, while others prefer to prior ligate (even laparoscopically)
the inferior epigastric vessels several months before the TRAM fl ap is raised to
effectively expand or “supercharge” the superior epigastric supply. Other surgeons
advocate harvesting both rectus muscles (bipedicled TRAMs), to gain more volume.
Expanders or implants are almost never used, and the exact limits of the breast
pocket need to be planned. The patient should be preloaded with intravenous crystalloid
solution to maximize fl ap perfusion.
Anatomical Points
Signifi cant variations in the anatomy of the chest wall, axilla, and abdominal wall
are uncommon. The rectus muscle may be broader and attached more laterally. The
inferior epigastric vessels are usually larger than the superior; rarely the inferior
vessels may be small. The epigastric veins are often duplex (double), and rarely
the artery may also be duplex. The rectus muscle is usually supplied predominantly
from below via the inferior epigastric vessels. The small branches of the inferior
epigastric piercing the anterior rectus fascia to supply the abdominal wall skin are
critical for the survival of the skin and subcutaneous tissue comprising the TRAM
fl ap. These branches can be very small and highly variable in location and number.
A preoperative vascular duplex U/S may be of use in locating and mapping these
vessels. The shape of the chest wall and rectus insertion may dictate the relative ease
of positioning of the pedicle for the tissue to be fashioned to form the “new” breast
mound. Kinking or constriction must not be allowed; otherwise the fl ap may suffer
vascular compromise and fail, due to either poor arterial infl ow or reduced venous
outfl ow. Previous abdominal surgery and scarring may alter the operative approach.
Perspective
Most complications from TRAM fl ap reconstructions are minor and
less serious. However, serious complications which require immediate intervention
are not uncommon. The most frequent early problems include venous congestion of
the distal part of the fl ap, leading to partial or rarely total fl ap necrosis/loss. Other
major complications include pulmonary emboli (~1 %), major hemorrhage (~1:500),
and infection of the chest or abdominal wound site(s). Prevention of DVT, careful
dissection, hemostasis, appropriate antibiotic cover, and adequate experience should
help to reduce the incidence of these events to well under 2 %. Risk of total fl ap loss
is generally higher for free than pedicled TRAM fl aps. It is much more common to
encounter less major complications, either early in the postoperative period or later.
The most frequent early problems include malposition of the fl ap or the skin island.
These can often be reduced by careful planning of fl ap design. Asymmetry is another
early common problem which can be minimized by intraoperative adjustment of the
size and shape of the breast. Prolonged drainage of serous fl uid and recurrent donor
site seroma formation are very common sequelae to this type of surgery, rather than
complications. Implants are very seldom used under TRAM fl ap breast reconstruction,
but if used can be associated with prosthetic specifi c complications (see section
on complications of implants). Patients may experience some loss of shoulder mobility
and strength or back pain, due to positioning of the arms during the prolonged procedure.
The abdominal donor site is a common source of complications, relating to
discomfort, pain, seroma formation, and sometimes later hernia formation. Chronic
donor site pain is not common and may be diffi cult to treat. Further “remodeling”
surgery is frequently necessary to attain the desired cosmetic outcome, including
reshaping of the fl ap, liposuction/lipofi lling, nipple/areolar reconstruction, and
reduction of the opposite breast, which the patient needs to be made aware of.
Major Complications
Major complications can be divided into those which require early (often immediate)
intervention and those which present later and are debilitating enough to affect
quality of life.
Early Complications
Total flap loss is infrequent which might be reduced by careful selection of
patients, understanding anatomy, any anomalies, pitfalls associated with any previous
surgery, and avoidance of tension. Full-thickness partial flap necrosis is not
uncommon and often only over a small area, but typically requires excision and
prolonged dressings. Skin envelope necrosis can arise after skin-sparing mastectomy.
It may be treated by excision and primary suture or excision and grafting,
depending on the extent of skin loss. Signifi cant hemorrhage beneath the fl ap or
into the donor site usually requires early exploration. Control of any bleeding points
can then be attained. Conservative treatment by continuing with closed drainage
may delay recovery and increase the risks of tension , fl ap ischemia, and infection .
Traction injuries to the brachial plexus and back pain are not uncommon after
prolonged surgery, and this risk may be reduced by careful padding and positioning.
Ulnar nerve paresis is higher in prolonged procedures with inadvertent arm
misplacement. Abdominal wall hematoma is relatively uncommon, but may internal
to the reconstructed abdominal wall and hence concealed. Multisystem organ
failure is very rare and together with fatal pulmonary emboli constitutes the usual
cause of mortality , which is rare.
Debilitating Late Complication
Later complications can arise in the reconstructed breast and/or in the abdominal
wall donor site. Rarely, severe infection or cellulitis of the chest wall, fl ap or
abdominal wall can arise, and wound dehiscence , skin ulceration , sinus formation,
and a chronic discharging wound and prolonged dressings may occur. This
may lead to cosmetic deformity resulting in breast asymmetry or abdominal wall
deformity . Seroma formation may occur in the breast/axillary region or at the
abdominal donor site. Abdominal wall hernia formation may occur and require
later surgical repair. Use of only part of the rectus muscle and limited use of mesh
may reduce the risks. Chronic infection of the mesh can also occur. Chronic pain
of the breast or abdominal wall is usually low grade if it occurs, but can rarely
be severe and unpredictable. Contraction of the reconstructed breast is rarely a
problem after free-TRAM fl ap reconstruction (compared with breast implant procedures),
but can occur with fat necrosis and infection with tissue loss, and after radiotherapy.
Umbilical distortion due to contraction and/or misplacement can occur
and may need surgical correction.
Progressive contralateral ptosis, fat necrosis, and changes in the fl ap can lead to
progressive asymmetry, lumpiness, and cosmetic deformity , which may require
further surgery. This can be a serious problem as a late consequence of reconstructive
surgery coincident with the effects of changing body shape during aging.
Severe systemic infection and multisystem organ failure are exceedingly rare, as
is mortality .
Local breast cancer recurrence in the reconstructed breast is typically <1 %
per annum. Recurrences deep to the fl ap are extremely rare and treatment will
depend on presentation. Localized “spot” recurrences in nonirradiated reconstructions
may be managed by local excision and radiotherapy, providing clear margins
can be achieved. “Field” recurrences will usually require additional systemic therapy.
Systemic recurrence is a more serious issue and related to the primary tumor
biology, rather than a consequence of reconstructive surgery.
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