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VASCULAR PEDICLE AVULSION IN FREE FLAP BREAST RECONSTRUCTION: A CASE OF DIEP FLAP SALVAGE FOLLOWING EARLY AVULSION OF VENOUS ANASTOMOSIS AND LITERATURE REVIEW EFSTATHIOS G. LYKOUDIS, M.D., Ph.D., * DIMOSTHENIS E. ZIOGAS, M.D., and GEORGE E. PAPANIKOLAOU, M.D. Free flap vascular pedicle avulsion represents an extremely rare complication in reconstructive microsurgery. Very few cases have been reported in the literature, most of them identified in free flap breast reconstruction. As a result, little data is currently available on the etiol- ogy and treatment of this rare complication. Herein, we report a unique case of early venous anastomosis avulsion following free DIEP flap transfer for delayed breast reconstruction. Venous outflow was successfully restored with the use of an interposition vein graft, and the flap survived completely. In addition, the relevant literature is reviewed; and the possible causes, preventive strategies, and management options are analyzed. V V C 2010 Wiley-Liss, Inc. Microsurgery 30:233–237, 2010. Free tissue transfer is considered the workhorse for breast reconstruction. These methods have high success rates and most importantly are associated with excellent cosmetic outcomes and great patient satisfaction. The use of a variety of flaps, mostly from the lower abdomen but also from other areas of the body, has been reported. 1,2 Regardless of the flap to be used, patency as well as integrity of the vascular anastomoses is crucial for a successful outcome especially in the early postoperative period. 3,4 Free flap failure in most cases is the result of anasto- motic occlusion. Nevertheless, other aetiologies resulting in disruption of vascular continuity, such as pedicle avul- sion or anastomotic aneurysm rupture, although extremely rare, have been reported. 5,6 Vascular pedicle avulsion appears to be a very rare complication, although some cases might have been undiagnosed or not reported. Very few cases have been reported in the literature to date; not only in free flap breast reconstruction, but also in other fields of free flap transfer. 7,8 As a result, little data is cur- rently available on its causes and management. Herein, we report a unique case of early venous anas- tomosis avulsion following free DIEP flap transfer for delayed breast reconstruction. Venous outflow was suc- cessfully restored with the use of an interposition vein graft, and the flap survived completely. The relevant liter- ature is also reviewed and guidelines for the prevention as well as the treatment of free flap vascular pedicle avulsion are suggested. CASE REPORT A 45-year-old nonsmoking woman underwent a DIEP flap for secondary reconstruction of her left breast. The flap was based on one medial perforator deriving from the left deep inferior epigastric vessels. On removal of the third costal cartilage, a duplicate venous system was encountered on either side of internal mammary artery. Each vein measured less than 0.5 mm in diameter, so both of them were deemed unsuitable for use. Despite removal of the second costal cartilage the veins had no greater diameter. An effort to expose the ipsilateral thora- codorsal vessels revealed that they were ligated and encased in a scar as a result of previous axillary dissec- tion, and were also deemed unsuitable for use. On the basis of our previous experience with the use of the external jugular vein for supplementary venous outflow of DIEP flaps, this vein was selected as the primary recipient. The external jugular vein was dissected through three small neck incisions at natural neck creases, ligated distally, flipped over the clavicle, tunneled into the breast pocket, and anastomosed to the deep inferior epigastric vein. The deep inferior epigastric artery was anastomosed to the internal mammary artery. Although the immediate postoperative period was uneventful, 24 hours later, the patient while vomiting felt an abnormal stretch sensation under the reconstructed breast and the flap became con- gested. On exploration, partial avulsion with thrombosis of the venous anastomosis was noted. Torn vessel wall with intact suture loops and knots were found, indicating mechanical force as the cause of avulsion. The anasto- motic site was resected, the clot was removed, and retro- grade isolated flap perfusion with 2.5 mg of rt-PA was performed. Then, an additional 3 mm traumatized seg- ment of the inferior epigastric and external jugular vein was resected. To accommodate the resulted vein defect and perform a tension free anastomosis, a segment of the right great saphenous vein was harvested. This was used Department of Plastic Surgery, Ioannina University School of Medicine, Ioannina, Greece *Correspondence to: Efstathios G. Lykoudis, M.D., Ph.D., Department of Plastic Surgrery, Ioannina University School of Medicine, University Campus, 45110, Ioannina, Greece. E-mail: [email protected] Received 13 October 2009; Accepted 2 November 2009 Published online 20 January 2010 in Wiley InterScience (www.interscience.wiley. com). DOI 10.1002/micr.20738 V V C 2010 Wiley-Liss, Inc.

Vascular pedicle avulsion in free flap breast reconstruction: A case of diep flap salvage following early avulsion of venous anastomosis and literature review

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Page 1: Vascular pedicle avulsion in free flap breast reconstruction: A case of diep flap salvage following early avulsion of venous anastomosis and literature review

VASCULAR PEDICLE AVULSION IN FREE FLAP BREASTRECONSTRUCTION: A CASE OF DIEP FLAP SALVAGEFOLLOWING EARLY AVULSION OF VENOUS ANASTOMOSISAND LITERATURE REVIEW

EFSTATHIOS G. LYKOUDIS, M.D., Ph.D.,* DIMOSTHENIS E. ZIOGAS, M.D., and GEORGE E. PAPANIKOLAOU, M.D.

Free flap vascular pedicle avulsion represents an extremely rare complication in reconstructive microsurgery. Very few cases have beenreported in the literature, most of them identified in free flap breast reconstruction. As a result, little data is currently available on the etiol-ogy and treatment of this rare complication. Herein, we report a unique case of early venous anastomosis avulsion following free DIEPflap transfer for delayed breast reconstruction. Venous outflow was successfully restored with the use of an interposition vein graft, and theflap survived completely. In addition, the relevant literature is reviewed; and the possible causes, preventive strategies, and managementoptions are analyzed. VVC 2010 Wiley-Liss, Inc. Microsurgery 30:233–237, 2010.

Free tissue transfer is considered the workhorse for

breast reconstruction. These methods have high success

rates and most importantly are associated with excellent

cosmetic outcomes and great patient satisfaction. The use

of a variety of flaps, mostly from the lower abdomen but

also from other areas of the body, has been reported.1,2

Regardless of the flap to be used, patency as well as

integrity of the vascular anastomoses is crucial for a

successful outcome especially in the early postoperative

period.3,4

Free flap failure in most cases is the result of anasto-

motic occlusion. Nevertheless, other aetiologies resulting

in disruption of vascular continuity, such as pedicle avul-

sion or anastomotic aneurysm rupture, although extremely

rare, have been reported.5,6 Vascular pedicle avulsion

appears to be a very rare complication, although some

cases might have been undiagnosed or not reported. Very

few cases have been reported in the literature to date; not

only in free flap breast reconstruction, but also in other

fields of free flap transfer.7,8 As a result, little data is cur-

rently available on its causes and management.

Herein, we report a unique case of early venous anas-

tomosis avulsion following free DIEP flap transfer for

delayed breast reconstruction. Venous outflow was suc-

cessfully restored with the use of an interposition vein

graft, and the flap survived completely. The relevant liter-

ature is also reviewed and guidelines for the prevention

as well as the treatment of free flap vascular pedicle

avulsion are suggested.

CASE REPORT

A 45-year-old nonsmoking woman underwent a DIEP

flap for secondary reconstruction of her left breast. The

flap was based on one medial perforator deriving from

the left deep inferior epigastric vessels. On removal of

the third costal cartilage, a duplicate venous system was

encountered on either side of internal mammary artery.

Each vein measured less than 0.5 mm in diameter, so

both of them were deemed unsuitable for use. Despite

removal of the second costal cartilage the veins had no

greater diameter. An effort to expose the ipsilateral thora-

codorsal vessels revealed that they were ligated and

encased in a scar as a result of previous axillary dissec-

tion, and were also deemed unsuitable for use. On the

basis of our previous experience with the use of the

external jugular vein for supplementary venous outflow

of DIEP flaps, this vein was selected as the primary

recipient. The external jugular vein was dissected through

three small neck incisions at natural neck creases, ligated

distally, flipped over the clavicle, tunneled into the breast

pocket, and anastomosed to the deep inferior epigastric

vein. The deep inferior epigastric artery was anastomosed

to the internal mammary artery. Although the immediate

postoperative period was uneventful, 24 hours later, the

patient while vomiting felt an abnormal stretch sensation

under the reconstructed breast and the flap became con-

gested. On exploration, partial avulsion with thrombosis

of the venous anastomosis was noted. Torn vessel wall

with intact suture loops and knots were found, indicating

mechanical force as the cause of avulsion. The anasto-

motic site was resected, the clot was removed, and retro-

grade isolated flap perfusion with 2.5 mg of rt-PA was

performed. Then, an additional 3 mm traumatized seg-

ment of the inferior epigastric and external jugular vein

was resected. To accommodate the resulted vein defect

and perform a tension free anastomosis, a segment of the

right great saphenous vein was harvested. This was used

Department of Plastic Surgery, Ioannina University School of Medicine,Ioannina, Greece

*Correspondence to: Efstathios G. Lykoudis, M.D., Ph.D., Department ofPlastic Surgrery, Ioannina University School of Medicine, University Campus,45110, Ioannina, Greece. E-mail: [email protected]

Received 13 October 2009; Accepted 2 November 2009

Published online 20 January 2010 in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/micr.20738

VVC 2010 Wiley-Liss, Inc.

Page 2: Vascular pedicle avulsion in free flap breast reconstruction: A case of diep flap salvage following early avulsion of venous anastomosis and literature review

as an interposition graft and anastomosed to the external jug-

ular vein proximally and the deep inferior epigastric vein dis-

tally (see Fig. 1). On completion of the anastomoses 5,000

IU of heparin were administered IV, microclamps were

released, venous outflow was restored and flap congestion

was relieved. The patient was subsequently maintained on

3,500 IU low-molecular weight heparin and 100 mg acetyl-

salicylic acid each day until she was discharged uneventfully

on the 10th day after the avulsion. The flap survived com-

pletely, although a small area of skin blistering was noted,

which healed spontaneously within few days. At three-month

follow-up, the flap was soft and supple without any signs of

fat necrosis (see Fig. 2).

DISCUSSION

Microvascular free tissue transfer is a reliable method

for breast reconstruction with high success rates, ranging

from 92% to 99%. These methods primarily include the

use of the transverse rectus abdominis musculocutaneous

(TRAM) flap and the deep inferior epigastric perforator

(DIEP) flap. However, the use of a variety of other flaps,

such as the superficial inferior epigastric artery (SIEA)

flap, the superior gluteal artery perforator (S-GAP) flap

etc, has been reported.1,2,3,9

Despite the aforementioned high success rates, there is

still a small risk of flap compromise due to major

Figure 1. Intraoperative photograph, demonstrating the stumps

(arrows) of the deep inferior epigastric and external jugular vein

(A); and the saphenous vein graft used for restoration of venous

outflow (B). [Color figure can be viewed in the online issue, which

is available at www.interscience.wiley.com.]

Figure 2. Photographs of the flap at 15 days (A) and 3 months (B)

postoperatively. [Color figure can be viewed in the online issue,

which is available at www.interscience.wiley.com.]

234 Lykoudis et al.

Microsurgery DOI 10.1002/micr

Page 3: Vascular pedicle avulsion in free flap breast reconstruction: A case of diep flap salvage following early avulsion of venous anastomosis and literature review

complications. The most commonly encountered major

complications are venous thrombosis, arterial thrombosis,

and bleeding/hematoma.3,4,10,11 Vascular pedicle avulsion

represents another serious complication, not only in breast

reconstruction but also in other fields of free tissue transfer.

Although extremely rare, disruption of the vascular pedicle

can lead not only to flap failure but may also threaten the

patient’s life, as a result of massive bleeding.12,13

A MEDLINE search of papers referring to free flap

vascular pedicle avulsion was followed by an extensive

manual search on the same topic, using references from

relevant published papers. A total of nine cases were

found, seven of which occurred in free flap breast recon-

structions, and are listed in detail in Table 1. Most of

them were case reports, although some sporadic cases

were identified in retrospective studies of breast recon-

struction with the use of free flaps.5,12–17

Vascular pedicle avulsion was encountered in four

different types of free flaps used for breast reconstruction.

In four cases both the artery and vein of the pedicle were

avulsed,13–16 while in three only the artery.5,12,17 Interest-

ingly our case represents the first and only report in the

literature, in which only the vein of the pedicle was

avulsed. Complete vessel avulsion was noticed in all

except for two cases, one of partial arterial avulsion5 and

our case of partial vein avulsion. Interestingly, pedicle

avulsion occurred almost exclusively at the site of anasto-

moses; which represents the area of minimal resistance to

injury. However in one case, the artery of the pedicle

was not avulsed at the anastomosis site but close to its

insertion into the flap.17 Vascular pedicle avulsion

occurred with the use of three different recipients: the

circumflex scapular,5 the thoracodorsal,12 and the internal

mammary vessels.13–17 In the majority of cases, five

including our case, the internal mammary vessels were

used. However, the small number of cases prevents us

from making any conclusive statement relating the inter-

nal mammary vessels with higher avulsion rates.

The aetiology of avulsion probably was the application

of excessive traction on the vascular pedicle. The mecha-

nism of the injury was evident in two cases of iatrogenic

aetiology that happened intraoperatively, and was the result

of high levels of strain exerted by the surgeon to the vascu-

lar pedicle.13,15 In the other five cases, there was no clear

avulsion mechanism.5,12,14,16,17 Nevertheless, possible

mechanisms seemed to be as follows: (1) inadvertent

abrupt forceful movements of the patient resulting in the

development of excessive traction forces on the vascular

pedicle of the flap, (2) inadequate support of a heavy and

pendulous flap exerting considerable traction on the pedi-

cle, and (3) a combination of the aforementioned mecha-

nisms. In our case, we suppose that neck hyperextension

during vomiting strained the vein against the clavicle and

resulted in partial avulsion of the anastomosis.

Table

1.VascularPedicle

Avulsionin

FreeFlapBreast

Reconstruction

Authors

Typeofflap

Recipientve

ssels

Avulsiontype

Tim

ePresentingsign

Treatm

ent

Complications

Outcome

Elliottetal.12(1990)

Lateraltransve

rse

thigh

Thoracodorsal

Complete

arterial

3rd

day

Flapischemia

None

–Flaploss

Gahankarietal.5

(2001)

DIEP

Circumflex

scapular

Partialarterial

5th

day

Flapischemia

Anastomosis

revision

Anastomosisocclusion—

successfulrevision

Complete

survival

Saldagoetal.1

3(2002)

TRAM

Notreported

Complete

arterial

andve

nous

3rd

month

Bleeding

None

–Partialflaploss

Heymansetal.1

4(2003)

S-G

AP

Internalmammary

Complete

arterial

andve

nous

8th

day

Notreported

None

–Complete

survival

Munhozetal.1

5(2004)

DIEP

Internalmammary

Complete

arterial

andve

nous

Intra-op

Bleeding

Anastomoses

revision

–Complete

survival

Geary

etal.16(2006)

DIEP

Internalmammary

Complete

arterial

andve

nous

15th

day

Bleeding

(hematoma)

Interposition

vein

grafts

Smallareaofbreakdown

Complete

survival

Enajatetal.17(inpress)

SIEA

Internalmammary

Complete

arterial

(notat

anastomosis

site)

11th

day

Bleeding

(hematoma)

Anastomosis

at

avulsionsite

Re-avulsionwithno

furthertreatm

ent

Partialflaploss

Free Flap Vascular Pedicle Avulsion 235

Microsurgery DOI 10.1002/micr

Page 4: Vascular pedicle avulsion in free flap breast reconstruction: A case of diep flap salvage following early avulsion of venous anastomosis and literature review

Vascular pedicle avulsion was associated either with

bleeding or vascular thrombosis. However, a sensation of

abnormal stretch or detachment of the flap was reported

in some patients.14,17 Bleeding, often associated with he-

matoma formation and acute swelling of the reconstructed

breast, was the most common presenting sign.13,15–17 In

one patient there was massive bleeding with signs of

acute hypovolemia.16 Flap ischemia due to early throm-

bosis of the ruptured vessel(s) was another presenting

sign.5,12 However in our case, flap congestion due to

early thrombosis of the partially avulsed venous anasto-

mosis was the presenting sign.

According to the data collected, emergency explora-

tion was almost exclusively performed aiming at bleeding

control in case of hemorrhage, flap salvage in case of

compromised blood supply, or both. In case of normal

blood perfusion of the flap, as a result of neovasculariza-

tion from the recipient area, ligation of the avulsed ves-

sel(s) was performed. Whereas in the case of flap com-

promise, restoration of vascular continuity was attempted

by means of direct anastomosis at the avulsion site5,15,17;

or the interposition of vein grafts.16 In one case, local

flap infusion with streptokinase was performed prior to

vascular continuity reconstruction.5 In our case, the treat-

ment aimed primarily at restoration of venous outflow.

Also, measures for prevention of rethrombosis, due to

intima damage inflicted by the avulsion injury mecha-

nism, were taken.18,19 On this basis, resection of the

anastomosis with an additional vein segment on either

side was performed, followed by local administration of a

thrombolytic agent for lysis of the established clot and

prevention of re-thrombosis. A vein graft was used to

restore vascular continuity in order to perform a tension

free anastomosis. Finally, antithrombotic agents were sys-

temically administered.

As for flap survival, four survived completely. Three of

them as a result of successful restoration of vascular conti-

nuity,5,15,16 and one as a result of neovascularization from

the recepient, despite failure to re-establish axial perfusion

on the 8th post-op day, which is not a common finding.14

However, there are certain reports, which have shown that

a period of 9 to 14 days allows for flap survival through

neovascularization, despite the loss of axial blood sup-

ply.8,14,20,21 Two flaps underwent partial necrosis after fail-

ure to re-establish axial blood supply at 11 days and 3

months respectively.13,17 A possible explanation of partial

flap necrosis at three months post-op was the presence of a

refractory to multiple aspirations seroma, that probably pre-

vented the development of adequate flap neovascularization

from the recipient bed. Finally, one flap failed since late

diagnosis of pedicle avulsion prevented any operative treat-

ment.12

Appropriate treatment for free flap vascular pedicle

avulsion is not well established in the literature because of

lack of case series. Nevertheless, according to data col-

lected from the literature and our case, although too small

and not well supported, certain guidelines are proposed for

the proper management of vascular pedicle avulsion on the

basis of the presenting sign, the degree of neovasculariza-

tion of the flap, as well as the condition and the quality of

the recipient bed. In the presence of clinical signs of pedi-

cle avulsion immediate surgical exploration should be per-

formed. Both the incision and dissection should be minimal

in order to disrupt as little as possible flap neovasculariza-

tion. In case of bleeding, microvascular clamps should be

applied at the stumps of the avulsed vessels to cease the

hemorrhage. If flap circulation is compromised, restoration

of vascular continuity should be performed by means of

anastomosis at the site of avulsion or by interposition of a

vein graft. Systemic anticoagulation should be adminis-

tered during the early postoperative period. With respect to

the use of local thrombolytic agents, such as streptokinase,

rt-Pa etc., the exact indication has not been clearly defined.

However, in the presence of an extensive established clot,

not easily removed during the exploration; local adminis-

tration of these agents may prove beneficial.4,22–24 When

flap circulation is not compromised, as a result of neovas-

cularization, ligation of the avulsed vessels is the only mea-

sure to be taken. However, in our opinion, restoration of

vascular continuity should be attempted in case of a poten-

tially poor recipient area (heavily irradiated, excessively

scarred, presence of chronic seroma etc.), since late loss of

flaps has been reported despite adequate intraoperative flap

circulation.25,26 It is also worth highlighting the value of

preventive strategies, which are gentle intraoperative flap

handling by the surgeon; as well as postoperative restrain

of the patient from abrupt forceful movements, and appli-

cation of adequate flap support, in order to prevent the de-

velopment of excessive traction forces on the vascular ped-

icle. Finally, the prophylactic use of interposition vein

grafts should be considered, if undue tension on the anasto-

moses is thought likely or is present during flap inset.

In conclusion, free flap vascular pedicle avulsion is an

extremely uncommon complication, which is associated

with bleeding and/or vascular pedicle thrombosis. Flap is-

chemia predominates in case of early avulsion of the ar-

tery or both the artery and the vein of the pedicle. How-

ever, if only the vein is avulsed, then flap congestion is

the presenting sign. The treatment aims at the control of

the bleeding, if present, as well as the salvage of compro-

mised flaps by means of restoration of vascular continuity.

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Free Flap Vascular Pedicle Avulsion 237

Microsurgery DOI 10.1002/micr