DELAY OF THE TRAM FLAP

MARK A. CODNER, MD, AND JOHN BOSTWICK III, MD

The TRAM flap delay is a reliable method that may increase TRAM blood flow and can be applied to selecthigh-risk patients undergoing breast reconstruction to improve flap safety. The delay technique involvesdivision of the inferior epigastric vessels 2 weeks before definitive TRAM flap reconstruction. The primaryindications include patients with significant risk factors and large volume tissue requirements. This articlereviews the indications and surgical technique of TRAM flap delay and illustrates the vascular anatomicalchanges that occur following the delay phenomenon.KEY WORDS: breast reconstruction, TRAM flap, plastic surgery, delay phenomenon

Evolution of breast reconstruction with increased useof the TRAM flap has included several technical modifi­cations aimed at maximizing flap reliability and minimiz­ing complications associated with tissue ischemia. Mod­ifications to improve blood flow have included upperTRAM flap with the elliptical design centered over theperiumbilical region,l,2 the double-pedicle TRAM flap,3,4the microvascular assisted ("supercharged") TRAM flap,Sand the free TRAM flap." Despite use of these modifi­cations, the incidence of fat necrosis and partial flap lossremains 5% to 10% in most series? Further understand­ing of the vascular changes following TRAM flap recon­struction may provide methods to decrease the incidenceof these complications.

Considerable research has defined the vascular anat­omy of the rectus abdominis musculocutaneous flap.8-l0Detailed anatomical studies describing the angiosomesand venosomes in this region have contributed to im­proved TRAM flap design. ll,12 Furthermore, experi­mental studies using the delay phenomenon have sug­gested an increase in the number of perfused vascularterritories.13,14 Modification of the TRAM flap by vascu­lar delay of the inferior epigastric vessels has been eval­uated as a method to improve flap reliability.

INDICATIONS FOR TRAM FLAP DELAY

The conventional unipedicle TRAM flap represents ourpreferred method for unilateral breast reconstruction inthe low risk patient. Analysis of clinical results over thepast 10 years has shown that complications are signifi­cantly increased in patients with risk factors that includeobesity, history of chest wall radiation, cigarette smok­ing, and abdominal scars. IS Although cigarette smoking

From the Section of Plastic, Reconstructive and Maxillo-Facial Sur­gery, Emory University School of Medicine, Atlanta, GA.

Send reprint requests to John Bostwick III, MD, The Emory Clinic,1327 Clifton Road, Atlanta, GA 30322.

Copyright © 1994 by W. B. Saunders Company1071-0949/94/0101-0003$05.00/0

as a single risk factor was not associated with an in­creased risk of fat necrosis, smoking was associated witha higher overall complication rate. Indications forTRAM flap delay included patients with multiple risk fac­tors who were felt to have a prohibitively high risk ofischemic complications with conventional bipedicle re­construction (Table 1). In addition, a volume require­ment in excess of the tissue available from a hemi-flap tomatch the normal breast was considered an indication forTRAM flap delay when associated with one or more riskfactors. Other relative indications included high-riskpatients who were not suitable candidates for microsur­gical reconstruction because of comorbid factors or pa­tients who had a delayed mastectomy with a scarred,irradiated axilla.

ADVANTAGES AND DISADVANTAGES

The main advantage of the TRAM flap delay may be im­proved flap safety and predictability due to an increase inthe blood flow to the TRAM flap. For unilateral breastreconstruction, bilateral vascular delay and bipedicleTRAM flap was performed in all cases to maximize arte­rial blood flow and venous drainage. In addition,TRAMflap delay may increase available tissue volume forlarge volume reconstructions.

The primary disadvantage of the TRAM flap delay wasthe requirement for an additional operation as well as a2-week waiting period before mastectomy. Morbidityassociated with the delay procedure has been minimal,and most patients were fully ambulatory 2 days after sur-

TABLE 1. Indications for TRAM Flap Delay

Multiple risk factors:Obesity: >25% above IBWRadiation: chest wallAbdominal scars: Midline, paramedian, kocherCigarette smoking: active smoking at TRAM flap

Large volume tissue requirementUnsuitable microsurgical candidate

22 Operative Techniques in Plastic and Reconstructive Surgery, Vol 1, No 1 (May), 1994: pp 22-27

Fig 1. The TRAM flap incision is outlined. Bilateral 4-cm in­cisions are made over the lateral rectus border for TRAM flapdelay.

SURGICAL TECHNIQUE

As previously indicated, TRAM flap delay is performed 2weeks before breast reconstruction. The procedure canbe performed on an outpatient basis under general anes­thesia and can be supplemented by the use of lidocainewith epinephrine for vasoconstriction. The design ofthe TRAM flap incision is marked, and bilateral 4-cm in­cisions are made along the inferior border of the TRAMflap overlying the lateral border of the rectus muscle(Fig 1).

The superficial inferior epigastric vessels are identifiedand ligated. A self-retaining retractor is used and therectus sheath is identified. A 3-cm transverse incision ismade over the lateral rectus sheath just superior to theinguinal ligament. Following medial retraction of themuscle, the deep inferior epigastric vessels are ligatedand divided preserving length (Fig 2). The fascia is re­approximated with absorbable sutures, and the skin isclosed.

TRAM Flap Delay

gery. Techniques to minimize the operation with endo­scopic surgery is currently under investigation.

<,<,

';I

I/

/.;'

- -~

II

\\

"

Rectus m.

/

Fig 2. After the rectus sheath isopened, the muscle is retractedmedially, exposing the inferiorepigastric vessels. The vesselsare ligated distally to preservevessel length.

/Fascia of externa lnd internal obliq e m.

~~~~jr-l-i/rr.IF,----±:--- Deep inferior epigastr ic v.

~,*~:r---I'--- Deep inferior epigastric a.

~~

23

TRAM Flap Elevation

After the 2-week delay period, the definitive TRAM flapreconstruction is performed. The abdominal ellipse in­cludes the TRAM flap delay incisions (Fig 3). It is notuncommon to enter a small seroma at the prior surgicalsite. The abdominal flap is elevated in the standard pre­fascial plane, and the remainder of the operation pro­ceeds in the usual manner. The rectus fascia is dividedat the level of the arcuate line. Additional vessel lengthcan be obtained in the event microassistance is antici­pated, although we have not found this necessary.

CONCLUSIONS

As technical modifications of the TRAM flap have im­proved flap reliability, patient exclusion criteria have less­ened making breast reconstruction with autologous tis­sue a safer option for more patients undergoing mastec­tomy. Select high-risk patients are consideredacceptable candidates for TRAM flap reconstruction.The technique of TRAM flap delay can be used to reducethe complication rate of the high-risk breast reconstruc­tion. Our experience with 15 high-risk patients withmultiple risk factors following TRAM flap delay hasshown no fat necrosis.

The vascular anatomical changes following the delayphenomenon have been beautifully described by Tayloret a1. 13 The precise anatomical changes have beenshown to occur in both the arterial and venous systems.Dilatation of arterial choke vessels results in capture ofadditional adjacent vascular territories, which improvesarterial circulation (Fig 4). Changes in the venous sys­tem include reversal of flow across regurgitant valves,which increases the capacity for venous return (Fig 5).14Clinical findings of improved flap reliability followingdelay and increased nutrient blood flow measured withlaser doppler flowmetry and intraoperative blood pres­sure are consistent with physiological changes of aug­mented arterial inflow with a decrease in venous conges­tion. 16•17

The primary approach to breast reconstruction in thehigh-risk patient for many surgeons is the free TRAMflap. Considerable clinical experience with the freeTRAM has confirmed the reliability of this procedure. IS

Blood flow is reportedly increased because of direct per­fusion of the periumbilical perforators from the inferiorepigastric system. Despite the dominant blood supply,fat necrosis occurs in 2% to 4% of free TRAM flaps, andthe risk of total flap loss is 6% to 10%.19-21 The TRAMflap delay may be an alternative to the free TRAM inselect high-risk patients. Further investigation will helpclarify the indications and best strategies for delay of theTRAM flap for high-risk breast reconstruction.

Fig 3. The bipedicle delayed TRAM flap Is ele­vated In the usual manner with the Incision In­cluding the previous surgical site.

<'"""'7' ~,.... Sca r from previousincision

Inferior epigastricvessels

---~k---- Choke vessels

~----,F--~ Adjacent vascularterritories

:ir- --- -t-- Superior epigastricvessels

24

la

After DelayAr erial Pa ern

Befa e elaA e ial Pa ern

....-:-+-,.--+----....;...,u eep epigastric a.

'11fJ-t1--~~~t::~,...- Superf icial epigastr ic a.

1 A lacent vase lar erritories

8

Fig 4. Schematic diagram of the arterialanatomy of the TRAM flap. Changes In thechoke vessels within the deep superiorepigastric system and between cutaneousvascular territories are shown before de­lay (A) and after delay (B). Augmentationof arterial Inflow Is shown.

25

Fig 5. Schematic diagram of the venous drainageof the TRAM flap. Changes In the avalvular oscil­lating veins and between vascular territories areshown before delay (A) and after delay (B). Re­versal of flow across the Infraumbilical valveswith increased venous drainage Is shown.

.....

Reversal of flow

Before Delaye ous at e

Venous valves (closed)

After DelayVenous Pa ern

\~+--Superficial epigastricveins

+-,...;.-- -tl-- - - '--Deep inferiorepigastric veins

8

26

REFERENCES1. Slavin SA, Goldwyn RM: The midabdom inal rectus abdominis

myocutaneous flap: Review of 236 flaps. Plast Reconstr Surg 81:189­199,1988

2. Mukherjee RP, Gottlieb V, Hacker LC: Experience with the ipsilat­eral upper TRAM flap for postmastectomy breast reconstruction.Ann Plast Surg 23:187-194, 1989

3. Ishii CH, Bostwick], Raine T], et al: Double-pedicle transverse ab­dominis myocutaneous flap for unilateral breast and chest wall re­construction. Plast Reconstr Surg 76:901-907, 1985

4. Wagner DS, Michelow B], Hartrampf CR: Double-pedicle TRAMflap for unilateral breast reconstruction. Plast Reconstr Surg 88:987­997, 1991

5. Harashina T, Sone K, Inoue T, et al: Augmentation of circulation ofpedicled transverse rectus abdominis musculocutaneous flaps bymicrovascular surgery. Br] Plast Surg 40:367-370, 1987

6. Holstrom H: The free abdominoplasty flap and its use in breastreconstruction. Scand ] Plast Reconstr Surg 13:423, 1979

7. Hartrampf CR, Bennett GK: Autogenous tissue reconstruction inthe mastectomy patient: A critical review of 300 patients. Ann Surg205:508-519, 1987

8. Moon HK, Taylor Gl: The vascular anatomy of rectus abdominismusculocutaneous flaps based on the deep superior epigastric sys­tem. Plast Reconstr Surg 82:815-831, 1988

9. Taylor GI, Watterson PA, Zeit RG: The vascular anatomy of theanterior abdominal wall: The basis for flap design. Perspect PlastSurg 5:1-28, 1991

10. Costa MAC, Carriquiry C, Vasconez LO, et al: An anatomic study ofthe venous drainage of the transverse rectus abdom inis musculo­cutaneous flap. Plast Reconstr Surg 79:208-217, 1987

11. Taylor GI, Caddy CM, Watterson PA, et al: The venous territories

(venosomes) of the human body : Experimental study and clinicalimplications. Plast Reconstr Surg 86:185-213, 1990

12. Taylor GI, Palmer JH: The vascular territories (angiosomes) of thebody: Experimental study and clinical applications. Br J Plast Surg40:113-141, 1987

13. Callegari PR, Taylor GI, Caddy CM, et al: An anatomic review of thedelay phenomenon: I. Experimental Studies. Plast Reconstr Surg89:397-407, 1992

14. Taylor GI, Corlett RJ, Caddy CM, et al: An anatomic review of thedelay phenomenon: II. Clinical applications. Plast Reconstr Surg89:408-418, 1992

15. Watterson PA, Bostwick J, Hester TR, et al: TRAM flap: correlatedwith a ten year clinical experience with 556 patients. Plast ReconstrSurg (in press)

16. Bostwick]. Nahai F, Watterson PA, et al:TRAMflap delay for breastreconstruction in the high risk patient: Definition of risk factors in556 patients and evaluation of a 10 year experience with TRAM flapdelay. Am Assoc Plast Surg 37-38, 1993 (abstr)

17. Drazan L, Hartrampf CR, Noel RT,et al:The value of vascular delayand other maneuvers in TRAM flap surgery. Am Assoc Plast Surg81-82, 1993 (abstr)

18. Grotting JC, Urist MM, Maddox WA, et al: Conventional TRAMflapversus free microsurgical TRAM flap for immediate breast recon­struction. Plast Reconstr Surg 83:828-844, 1989

19. Amez 2M, Bajec J, Bardsley AF, et al: Experience with 50 freeTRAM flap breast reconstructions. Plast Reconstr Surg 87:470-482,1991

20. Elliott LFEskenazi L, Beegle PH, et al: Immediate TRAM flap breastreconstruction: 128 consecutive cases. Plast Reconstr Surg 92:217­227,1993

21. Schusterman MA, Kroll SS, Weldon ME: Immediate breast recon­struction: Why the free TRAM over the conventional TRAM flap?Plast Reconstr Surg 90:255-262, 1992

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