Management of complications following autologous breast reconstruction

Mastectomy flap necrosis

Immediate breast reconstruction (IBR) can offer excellent aesthetic results due to the preservation of the native skin envelope and, where appropriate, the nipple–areolar complex. Mastectomy flap necrosis (MFN) is among the most common complications in IBR with an incidence of 5%–30% reported in the current literature. Factors that may predispose to MFN include large breast volume, obesity, previous or new intraoperative breast scars, prior radiation and smoking. Determining the viability of the skin flaps at the time of mastectomy can be challenging. Intraoperative use of indocyanine green angiography (ICG-A) can provide a more objective assessment of skin flap perfusion but the exact thresholds for tissue survival remain unclear.

There are three possible scenarios when assessing the mastectomy flaps intraoperatively:

• 1.

  It may be very clear that a portion of the mastectomy flap is not viable, in which case it should be excised back to healthy bleeding tissue. There is a delicate balance between excising too much and removing too little skin and ICG-A assessment may assist in this decision-making process. Fortunately, in autologous reconstruction the excised skin can be replaced with flap skin but this is likely to compromise the overall aesthetic outcome.

• 2.

  The viability of the mastectomy flap may be unclear. In these cases, minimal or perhaps even no skin excision is performed. As the underlying tissue transfer is well perfused the mastectomy flaps can be left in place and the viability monitored in the postoperative period. Alternatively, a portion of the flap skin can be left in situ under the mastectomy flaps. In the event that the mastectomy skin does not survive and demarcates it can be removed and replaced with flap skin in a second procedure after 3–7 days.

• 3.

  Mastectomy flaps may appear viable intra-operatively but become necrotic in the postoperative period.

Typically, the non-viable mastectomy skin will demarcate and form an eschar that will separate slowly over time. Wound healing will be delayed but these cases can frequently be treated conservatively with dressings. In cases where the area of necrosis is larger or the patient is particularly anxious, formal debridement and skin grafting may be required. Skin grafts can be harvested from conventional donor sites or the other breast in cases where the procedure is combined with a contralateral balancing reduction or mastopexy. The need for adjuvant treatments such as mastectomy radiation or chemotherapy may lower the threshold for early intervention to facilitate timely wound healing. Both conservative management and skin grafting result in additional scarring and possible distortion of the skin envelope, which will adversely affect the cosmetic outcome.

Total flap failure

In spite of very high success rates flap failure remains an inherent risk in autologous breast reconstruction. Failure rates of 0.5%–2% are reported in most high-volume specialist centers. Failure is generally identified intra-operatively or early in the postoperative period. In microvascular cases close flap monitoring in the immediate postoperative period will allow early identification of flap compromise and increase the chance of a successful salvage procedure. A number of devices have been developed to aid early detection of flap perfusion issues, including implantable Dopplers and tissue oxygenation monitors. However, these options tend to be expensive with high false positive rates and have not been found to be consistently superior to sound clinical monitoring. When flap compromise is suspected, patients must be promptly returned to the operating room for exploration. Revision of the arterial and venous anastomoses may be necessary when intravascular thrombosis has occurred. Additional measures such as intra-flap injection of thrombolytics or introduction of angioplasty catheters may be required in cases where clot has propagated more extensively. In some instances, the anastomoses may be running normally and flap perfusion issues may be due to perforator insufficiency, which is more challenging but can be improved by reducing flap size or adding supplementary venous drainage, as described later in this chapter.

In cases where the flap cannot be salvaged, attention turns to offering an alternative option for breast reconstruction. In immediate reconstructions, and in some tertiary cases, it is possible to preserve the skin envelope by placing a tissue expander with or without acellular dermal matrix. This is often the most satisfactory option for patients as it allows them to recover from the initial surgery and any salvage efforts and gives them time to carefully consider the options for future reconstruction. It also gives the surgeon an opportunity to reflect on and address any modifiable factors that may have contributed to the failure. Some patients will prefer to undergo a secondary autologous reconstruction at the time of the initial failure ( Figs. 41.1 & 41.2 ). This may be preferable in delayed reconstruction where temporizing with a tissue expander is not usually an option due to mastectomy skin envelope insufficiency and skin grafting may be required for closure. A failed free flap can usually be readily replaced with a pedicled latissimus dorsi flap and tissue expander. However, if the patient prefers to avoid alloplastic material a second free flap can also be considered if there is an appropriate available donor site.

In all cases, management decisions should be made promptly and surgery should be performed within a week of the initial flap failure to minimize the risk of infections, which may compromise the outcome of secondary reconstruction.