Supercharged Pedicled TRAM Flap in Breast Reconstruction: Is It a Worthwhile Procedure

taken from the "Annals of Plastic Surgery Volume 40/ Number 3 / September 2002"

Hamdy Hamid EI-Mrakby, MD, FRCS
R. H. Milner, MD, FRCS
N. R. McLean, MD FRCS

A clinical study of the incidence of vascular complications in free and supercharged pedicled transverse rectus abdominis musculocutaneous (TRAM) flaps was undertaken. The complications associated with each of these two TRAM flaps were assessed. The incidence of vascular complications in the supercharged pedicle was found to be twice that associated with the free TRAM flap (36% vs. 18%); however, these results did not reach significance (p = 0.2). Fat necrosis was the most common complication in each group, with the overall rate being 17%. The incidence in the supercharged TRAM flap (29%) was more than twice that in the free TRAM flap (13%; p = 0.2). Partial flap loss was also greater in the charged flap than in the free flap (14% vs. 3%, p = 0.1). The results, however, did not reach significance, and this may be related to the relatively small sample size (52 patients). Vein grafts were used more often in the supercharged pedicled TRAM flap (p = 0.02). Obesity was also associated more frequently with the supercharged pedicled TRAM flaps (p = 0.07). Other risk factors were nearly equally distributed between either type of the flap. The results of the study support the continued use of the free TRAM flap. There appears to be no additional advantage in charging the pedicled TRAM with a microvascular anastomosis because the results were found to be inferior to those of the free TRAM flap. Other clinical factors, however, may dictate the type of flap used. A larger series is required to assess the importance of each of the risk factors affecting flap survival.

El-Mrakby HH, Milner RH, McLean NR. Supercharged pedicled TRAM flap in breast reconstruction: is it a worthwhile procedure.
Ann Plast Surg 2002;49:252257

From the Department of Plastic Surgery, Royal Victoria Infirmary, Newcastle-upon-Tyne, England.

Received Sep 18, 2001, and in revised form Feb 15, 2002. Accepted for publication Feb 18, 2002.

Address correspondence and reprint requests to Dr EI-Mrakby, Department of Surgery, National Cancer Institute, Fom El-Fhalig from Kasr Elini Street,Cairo, Egypt .

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The technique of breast reconstruction using the transverse rectus abdominis musculocutaneous (TRAM) flap has become the gold standard method of breast reconstruction. Complications reported in patients undergoing this procedure are related to softtissue necrosis secondary to ischemia,1 with vascular complications and donor site morbidity the most common postoperative complications.2,3

The lower TRAM flap is the most popular type. Basing the flap over the lower abdomen provides a large amount of tissue with a wide arc of rotation, and the location of the donor scar can be concealed in the suprapubic region.4

Early postoperative vascular problems (within 1 month of the operation) included partial flap loss, total flap loss, and early fat necrosis. Late vascular problems have been reported (as long as 12 months) and include fat necrosis.5 This is defined as an area of induration under the skin of the flap. The development of this new mass increases patient anxiety, reduces the quality of an otherwise adequate surgical result, and frequently results in reexploration.6

Several modifications of the superior pedicle technique have been adopted in attempt to reduce the incidence of vascular complications. Some of these techniques involve the use of two vascular pedicles or the supercharged superior pedicle flap and the turbocharged flap.1 The supercharged superior epigastric pedicled TRAM flap is a pedicled TRAM flap, with its blood supply augmented by an arterial and venous microvascular anastomosis. One method of charging the pedicle is to use the ipsilateral deep inferior epigastric vessels for the microvascular anastomosis. After harvesting the flap, a subcutaneous tunnel is created in the lower part of the chest between the abdominal wound and the site of the mastectomy. The flap is rotated 180 deg so that the distal part of the flap with the deep inferior epigastric pedicle sits in the axilla. 7,8

In this clinical study we compared the incidence of vascular complications in two types of TRAM flaps (the free TRAM flap and the supercharged pedicled TRAM flap). Risk factors for flap complications were studied and correlated with each type of flap.

Patients and Methods

A total of 52 consecutive patients who underwent breast reconstruction using a TRAM flap during the last 5 years (1994 - 1999) were included in the study. They were asked to attend a follow-up clinic and were assessed by two independent examiners, neither of who was part of the surgical team who performed the initial reconstructive surgery. Photographs of the reconstructed breasts were taken at the clinic.

Two reconstructive techniques were undertaken (38 free TRAM flaps, 14 supercharged pedicled TRAM flaps). The free TRAM flap was the routine method of breast reconstruction. The supercharged pedicled TRAM flap was used randomly in a subset of patients with no specific preoperative selection criteria. It was presumed that the additional microvascular anastomosis in the supercharged pedicled TRAM flap would increase the blood flow to the superior pedicled TRAM flap (IN 15).

The free TRAM flap operation was performed using a two-team approach. One team performed the mastectomy or excised the mastectomy scar and prepared the recipient vessels while the other team harvested the flap. Thc supercharged superior epigastric flap was performed following the same technique; however, the upper origin of the muscle was not divided but the flap was rotated through a subcutaneous tunnel between the site of mastectomy and the abdominal wall. The deep inferior epigastric vessels were anasto mosed with the thoracodorsal vessels or the cir cumflex scapular branches of the axillary artery.

The flaps were monitored postoperatively for skin color, capillary refill time, skin temperature, and in some cases with a Doppler probe. Patients were encouraged to mobilize after 2 or 3 postop erative days, with a protective abdominal support being used for 2 to 3 months.

The vascular complications were classified as partial flap loss, subtotal flap loss, or total flap loss, and fat necrosis. Partial flap loss was defined as an area of both skin and subcutaneous adipose tissue loss less than or equal to 10% of the flap. Subtotal or total loss included more than 10% loss of the flap, and these required surgical revi sion. Fat necrosis was evaluated and diagnosed clinically as an area of induration or firmness within the flap (N = 13), and was reported as long as 12 months postoperatively.

Statistical analysis was performed using the Minitab statistical software package. The two sample Student's t-test was used to compare the risk factors between the free and the charged pedicled TRAM flap groups. Chi-squared analysis and Fisher's exact test were used to compare the effect of various parameters (smoking, obe sity, radiotherapy, etc.) on vascular complica tions. The chi-squared test was used when each of the groups for comparison was more than five, whereas Fisher's exact test was used when any of the groups was less than five.

Results

Breast reconstruction using TRAM flaps was car ried out in 52 patients after undergoing a mastec tomy for breast cancer. Reconstruction was undertaken as an immediate procedure after mas tectomy in 15 patients (29%) and as a delayed procedure in 37 patients (71%).

Vascular complications (partial flap loss, subtotal or total loss, and fat necrosis) were recorded in 12 pa tients (23%). Partial flap loss was reported in 3 patients (6%), and total flap loss was noted in 1 patient (2%). Late fat necrosis was reported in 9 patients (17%; Tables 1 and 2). Fat necrosis and partial flap loss were reported in 1 patient. This patient had partial flap necrosis during the early postoperative period, which was excised Six months later, an indurated area adjacent to the previously excised necrosed area developed. Most cases of fat necrosis (72%) were treated conservatively, and the rest (28%) required secondary operation.

Surgical treatment of flap necrosis was often required. Minimal debridement of the distal part of the flap was performed in 1 patient whereas major excision was performed in 3 patients. In 1 patient, subtotal excision of the flap and latissi mus dorsi flap salvage was required.

The complication rate in the supercharged TRAM flap group was twice that compared with the free TRAM flap group (36% vs. 18%; p = 0.2).

(a) 1 = preoperative; 2 = postoperative.
(b) o = not used; 1 = used.
BMI = body mass index; FN = fat necrosis; TN = total necrosis; PN = partial necrosis.

TRAM = transversed rectus abdominis musculocutaneous.

Fat necrosis was seen more often in the supercharged TRAM flap compared with the free TRAM flap (29% vs. 13%; p = 0.2). Partial flap loss was also found more in the supercharged TRAM flap than the free TRAM flap (14% vs. 3%; p = 0.1; Table 3 and Fig 1). Most patients stayed in the hospital less than 2 weeks (N = 47 or 90%; average, 11 days). Four patients who had flap complications stayed in the hospital more than 2 weeks. One additional patient had an abdominal wound infection and stayed in the hospital for 16 days.

Various risk factors were studied and correlated to the type of flap used. Only vein grafts were used frequently with the supercharged pedicled TRAM flaps (p = 0.02). Vein grafts were used electively at the time of the primary microvascular anastomosis in 1 patient only. In this patient the vein graft was used to bridge the gap between the donor and the recipient vascular pedicle. Extensive scarring resulting from previous exnloration in the axilla in that natient was the cause of shortening of the recipient vascular pedicle. On the other hand, vein grafts were used as a salvage procedure when the flap was revised for vascular problems in 3 patients. Obesity was also associated more frequently with the supercharged pedicled TRAM flap (p = 0.07). The other risk factors were distributed nearly equally between either type of flap (Table 4)

Over all, 24 patients (46%) required secondary surgery to achieve a satisfactory aesthetic result. Four patients (8%) required small scar adjustments, 2 patients (4%) required ipsilateral reduction of the reconstructed breast, and 3 patients (6%) needed ipsilateral augmentation. Ancillary surgery to the contralateral breast was indicated in a subset of patients. Three patients (6%) required reduction mammaplasty whereas 4 patients (8%) required contralateral augmentation using a breast implants. Nippleareolar reconstruction was performed in 17 patients (33%). Two or more ancillary surgeries were needed in 9 patients (17%) after the reconstructive surgery (Table 5).

Discussion

The pedicled TRAM flap was described initially in 1982,~ and since then it has gained in popularity. Within a short time its use as a free tissue transfer was well established. 10,11

Vascular complications are the most common postoperative complication of the TRAM flap, with fat necrosis being the most prevalent." Other complications include partial flap loss and total flap necrosis, reflecting poor circulation to the flap.3 Fat necrosis may present as minor necrosis if it involves 10% of the flap or major necrosis if more than 10% 5 Its presence can induce anxiety in the patient and concern about tumor recur rence. On occasion, fat necrosis needs surgical re-exploration, and may become infected secondarily and require surgical drainage. 6

Copyright 2002 by Lippincott Williams & Wilkins, Inc.