William G. Austen

Breast reconstruction following nipple-sparing mastectomy: predictors of complications, reconstruction outcomes, and 5-year trends.

Background: Nipple-sparing mastectomy is increasingly used for treatment and prevention of breast cancer. Few data exist on risk factors for complications and reconstruction outcomes. Methods: A single-institution retrospective review was performed between 2007 and 2012. Results: Two hundred eighty-five patients underwent 500 nipple-sparing mastectomy procedures for breast cancer (46 percent) or risk reduction (54 percent). The average body mass index was 24, and 6 percent were smokers. The mean follow-up was 2.17 years. Immediate breast reconstruction (reconstruction rate, 98.8 percent) was performed with direct-to-implant (59 percent), tissue expander/implant (38 percent), or autologous (2 percent) reconstruction. Acellular dermal matrix was used in 71 percent and mesh was used in 11 percent. Seventy-seven reconstructions had radiotherapy. Complications included infection (3.3 percent), skin necrosis (5.2 percent), nipple necrosis (4.4 percent), seroma (1.7 percent), hematoma (1.7 percent), and implant loss (1.9 percent). Positive predictors for total complications included smoking (OR, 3.3; 95 percent CI, 1.289 to 8.486) and periareolar incisions (OR, 3.63; 95 percent CI, 1.850 to 7.107). Increasing body mass index predicted skin necrosis (OR, 1.154; 95 percent CI, 1.036 to 1.286) and preoperative irradiation predicted nipple necrosis (OR, 4.86; 95 percent CI, 1.0197 to 23.169). An inframammary fold incision decreased complications (OR, 0.018; 95 percent CI, 0.0026 to 0.12089). Five-year trends showed increasing numbers of nipple-sparing mastectomy with immediate reconstruction and more single-stage versus two-stage reconstructions (p < 0.05). Conclusions: Nipple-sparing mastectomy reconstructions have a low number of complications. Smoking, body mass index, preoperative irradiation, and incision type were predictors of complications. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Infection following implant-based reconstruction in 1952 consecutive breast reconstructions: salvage rates and predictors of success.

Background: Few studies address salvage rates for infection in implant-based breast reconstruction. An understanding of success rates and clinical predictors of failure may help guide management. Method: A retrospective analysis of multisurgeon consecutive implant reconstructions from 2004 to 2010 was performed. Results: Immediate implant-based reconstructions (n = 1952) were performed in 1241 patients. Ninety-nine reconstruction patients (5.1 percent) were admitted for breast erythema and had a higher incidence of smoking (p = 0.007), chemotherapy (p = 0.007), radiation therapy (p = 0.001), and mastectomy skin necrosis (p < 0.0001). There was no difference in age, body mass index, or acellular dermal matrix usage. With intravenous antibiotics, 25 (25.3 percent) reconstruction patients cleared the infection, whereas 74 (74.7 percent) underwent attempted operative salvage (n = 18) or explantation (n = 56). Patients who failed to clear infection had a higher mean white blood cell count at admission (p < 0.0001). Of the attempted operative salvage group, 12 cleared the infection with immediate implant exchange and six eventually lost the implant. Patients who failed implant salvage were more likely to have methicillin-resistant Staphylococcus aureus (p = 0.004). The total explantation rate was 3.2 percent. Following explantation, 32 patients underwent attempted secondary tissue expander insertion. Twenty-six were successful and six had recurrent infection and implant loss. There were no differences in time interval to tissue expander insertion between successful and unsuccessful secondary operations. Conclusions: Salvage with intravenous antibiotics and implant exchange was successful in 37.3 percent of patients. Smoking, irradiation, chemotherapy, and mastectomy skin necrosis were predictors for developing infection. Patients with a higher white blood cell count at admission and methicillin-resistant S. aureus were more likely to fail implant salvage. There was no association with time interval to tissue expander insertion and secondary explantation.(Plast. Reconstr. Surg. 131: 1223, 2013.) CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

The effect of pressure and shear on autologous fat grafting.

1. Aygit AC, Basaran K, Mercan ES. Transaxillary totally subfascial breast augmentation with anatomical breast implants: Review of 27 cases. Plast Reconstr Surg. 2013;131:1149–1156. 2. Hwang K, Kim DJ. Anatomy of pectoral fascia in relation to subfascial mammary augmentation. Ann Plast Surg. 2005;55:576–579. 3. Jinde L, Xiaoping C, Wanquan Z, Xia G, Ligang X. Can the pectoral fascia integrity be preserved during subfascial breast augmentation through the axillary approach? Aesthetic Plast Surg. 2010;34:29–32. 4. Salgarello M, Visconti G, Barone-Adesi L, et al. Inverted-T skin-reducing mastectomy with immediate implant reconstruction using the submuscular-subfascial pocket. Plast Reconstr Surg. 2012;130:31–41. 5. Salgarello M, Visconti G, Barone-Adesi L. One-stage immediate breast reconstruction with implants in conservative mastectomies. In: Salgarello M, ed. Breast Reconstruction: Current Techniques. Rijeka, Croatia: In-Tech; 2012:49–82. Available at: www.intechopen.com.

Non-thermal, pulsed electric field cell ablation: A novel tool for regenerative medicine and scarless skin regeneration

High voltage, short pulsed electric fields (PEF) is a non-thermal ablation method, in which defined PEF irreversibly destabilize cell membranes, while preserving other tissue components such as the extracellular matrix (ECM). In the present report, we show that PEF ablated rat skin retains its microvascular blood supply and ECM structure. Complete regeneration of epidermis, hair follicles, sebaceous glands, and the panniculus carnosusis observed two months after the ablation. Our results clearly indicate that non-thermal PEF has the potential to be a powerful and novel tool for scarless tissue regeneration.

Ischemic Preconditioning of Skeletal Muscle Mitigates Remote Injury and Mortality

BACKGROUND Ischemic preconditioning (IPC) mitigates ischemia-reperfusion (I/R) injury in experimental models. However, the clinical significance of this protection has been unclear and a mortality reduction has not been previously reported in noncardiac models. This study examined the local and remote protection afforded by skeletal muscle IPC and sought to determine the significance of this protection on mortality. METHODS Mice subjected to 2 h hindlimb ischemia/24 h reperfusion (standard I/R injury) were compared with those undergoing a regimen of two 20-min cycles of IPC followed by standard I/R injury. Local injury was assessed via gastrocnemius histology, and remote injury was evaluated via intestinal histology and pulmonary neutrophil infiltration (n = 7). Mortality was compared in parallel groups for 1 week (n = 6). Groups were analyzed using an unpaired Students t-test for gastrocnemius and pulmonary injury, and a Mann-Whitney rank sum test for intestinal injury. Mortality differences were interpreted through a hazard ratio. RESULTS Significant protection was observed in preconditioned animals. There was a 35% local injury reduction in skeletal muscle (71.2% versus 46.0%, P < 0.01), a 50% reduction in remote intestinal injury (2.3 versus 1.1, P < 0.01), and a 43% reduction in remote pulmonary injury (14.9 versus 8.5, P < 0.01) compared with standard injury controls. Preconditioned animals were also significantly protected from mortality, demonstrating a 66.7% survival at 1 wk compared with 0% survival after standard injury alone (hazard ratio 0.20, 95% CI: 0.02-0.59). CONCLUSIONS We have developed a murine model of IPC that demonstrates local and remote protection against I/R injury, and exhibits significant mortality reduction. This model demonstrates the powerful effect of IPC on local and remote tissues and will facilitate further study of potential mechanisms and therapies.

Skin Rejuvenation with Non-Invasive Pulsed Electric Fields

Degenerative skin diseases affect one third of individuals over the age of sixty. Current therapies use various physical and chemical methods to rejuvenate skin; but since the therapies affect many tissue components including cells and extracellular matrix, they may also induce significant side effects, such as scarring. Here we report on a new, non-invasive, non-thermal technique to rejuvenate skin with pulsed electric fields. The fields destroy cells while simultaneously completely preserving the extracellular matrix architecture and releasing multiple growth factors locally that induce new cells and tissue growth. We have identified the specific pulsed electric field parameters in rats that lead to prominent proliferation of the epidermis, formation of microvasculature, and secretion of new collagen at treated areas without scarring. Our results suggest that pulsed electric fields can improve skin function and thus can potentially serve as a novel non-invasive skin therapy for multiple degenerative skin diseases.

Eradication of multidrug-resistant A. baumannii in burn wounds by antiseptic pulsed electric field

Emerging bacterial resistance to multiple drugs is an increasing problem in burn wound management. New non-pharmacologic interventions are needed for burn wound disinfection. Here we report on a novel physical method for disinfection: antiseptic pulsed electric field (PEF) applied externally to the infected burns. In a mice model, we show that PEF can reduce the load of multidrug resistant Acinetobacter baumannii present in a full thickness burn wound by more than four orders of magnitude, as detected by bioluminescence imaging. Furthermore, using a finite element numerical model, we demonstrate that PEF provides non-thermal, homogeneous, full thickness treatment for the burn wound, thus, overcoming the limitation of treatment depth for many topical antimicrobials. These modeling tools and our in vivo results will be extremely useful for further translation of the PEF technology to the clinical setting, as they provide the essential elements for planning of electrode design and treatment protocol.

Alternatives to Acellular Dermal Matrix for Implant-Based Breast Reconstruction

Alloplastic reconstruction has evolved as the most popular technique for post-mastectomy breast reconstruction for the appropriate patient population. Acellular dermal matrices (ADMs) offer many advantages in optimizing aesthetic results and have gained significant popularity in recent years. Their use as an inferolateral sling has expanded the plastic surgeon’s armamentarium to include immediate direct-to-implant reconstructions. However, ADMs have been reported to result in increased complication rates, particularly with regard to infection and seroma formation. In addition, they are costly to manufacture and produce. Therefore, alternatives to ADMs are discussed that may serve to lower complication rates and cost without sacrificing aesthetic results.