Seroma Formation in Rat Latissimus Dorsi Resection in the Presence of Biologics: The Role of Quilting.

BACKGROUND: Seroma formation is a well-recognized complication associated with many operative procedures. Despite its ubiquity, a lack of definitive scientific understanding of the etiology, natural history, and biochemistry of seromas remains. We endeavored to create and examine seromas in a rat model in the setting of commonly used biologic implants and to examine the role of quilting sutures/mechanical fixation in mitigating seroma development. METHODS: Female Sprague-Dawley rats were assigned to either Quilting or Nonquilting groups then subdivided into one of 3 porcine dermal implant groups (Permacol Surgical Implant, Strattice Reconstructive Tissue Matrix, or XCM Biologic Tissue Matrix) or control group. A 5-cm midline back incision was made, the skin reflected and the latissimus dorsi muscle resected bilaterally. Implants were sutured into the surgical bed using a running suture. The skin of nonquilted rats was closed with a running subcuticular suture. Quilted rats underwent placement of absorbable quilting sutures spaced 2 cm apart between the skin and underlying implant or muscle before skin closure. Postoperatively, rats were monitored for seroma formation with fluid aspirated as needed. At 28 or 90 days, rats were euthanized. Seroma and implants were examined grossly and under light microscopy. RESULTS: Of nonquilted rats, 42/54 (78%) developed seromas compared with 19/46 (41%) of quilted rats (P < 0.05), defined by bursa cavity present at necropsy. When a biologic implant was present, 28/35 (80%) of nonquilted rats developed seromas compared with 12/33 (36%) of quilted rats (P < 0.05). In the control group, 14/19 (74%) of nonquilted rats developed seromas compared with 7/13 (54%) of quilted rats. This difference was not statistically significant. Bursa presence was confirmed histologically in all cases, with no difference in bursa character seen between groups. CONCLUSIONS: This study confirms a reliable rat model of seroma formation, with most of the rats exhibiting at least subclinical seromas. There was no difference in seroma formation rate in the presence of biologic implants, and no differences in bursa character between implants. Mechanical fixation with quilting sutures decreased seroma rate significantly in all subgroups. All rats with seromas at necropsy had histological evidence of a bursa with no difference in appearance between groups.

Accelerated porcine wound healing after treatment with α-gal nanoparticles.

BACKGROUND: The α-gal epitope is a carbohydrate antigen that interacts specifically with the natural anti-Gal antibody--the most abundant antibody in humans. Anti-Gal/α-gal epitope interaction activates complement to generate chemotactic factors that induce rapid recruitment of macrophages. The authors hypothesized that α-gal epitopes on nanoparticles can accelerate wound healing by inducing rapid recruitment and activation of macrophages in wounds. METHODS: α-Gal nanoparticles were generated from phospholipids, cholesterol, and α-gal glycolipids. α-Gal nanoparticle treatment of wounds was studied in 12 α1,3galactosyltrasferase knockout pigs. Like humans, these pigs lack α-gal epitopes and produce the natural anti-Gal antibody. Full-thickness wounds (20 × 20 mm) with tattooed borders were created on the back of pigs. α-Gal nanoparticles (10 or 100 mg) were topically applied onto the wounds. Saline-treated wounds served as control. Wound open surface area was measured every 3 to 4 days during dressing changes. Wounds from euthanized pigs were subjected to histological evaluation. RESULTS: Treated wounds displayed many more macrophages and increased angiogenesis than control wounds in the same pig. On day 10, wounds treated with 10 mg and 100 mg displayed 35 and 60 percent decreased open surface area compared with control wounds, respectively, and 80 and 90 percent less than control wounds on day 13 (p < 0.05). No keloid formation or no increase in scar formation was observed on day 60. CONCLUSIONS: α-Gal nanoparticle treatment of wounds accelerates macrophage recruitment, angiogenesis, and wound healing in pigs producing the anti-Gal antibody. As humans produce high titers of anti-Gal antibodies, this treatment may exhibit a similar beneficial effect in the clinical setting.

Fleur-de-lis panniculectomy after bariatric surgery: our experience.

BACKGROUND: Plastic surgeons are faced with increasing numbers of patients presenting for insurance-covered skin excision procedures following bariatric surgery. Panniculectomy for symptomatic relief of rashes is commonly performed, but an isolated infraumbilical amputation-type panniculectomy is a highly unaesthetic procedure, leaving many patients deeply dissatisfied. It may be also fraught with complications due to large incisions and potential for dead-space. In these patients, many surgeons avoid the fleur-de-lis panniculectomy, despite the body contour aesthetic advantage, because of increased time, more scarring, and a perceived increase in complications. METHODS: This is a retrospective chart review of 130 consecutive postbariatric surgery patients who had panniculectomy over a 2-year period at our institution. RESULTS: A total of 30 patients underwent a traditional panniculectomy and 100 patients had a fleur-de-lis panniculectomy. Mean weight loss from bariatric surgery to panniculectomy was 58.2 kg, with an average body mass index (BMI) of 30. Fifty-seven patients had additional procedures performed at the time of panniculectomy. Twenty-two patients (17%) had complications, with 5 in the traditional group (17%) and 17 in the fleur-de-lis group (17%) (P = 1.0). Six males (40%) had more complications compared with 18 females (15.7%) (P = 0.034). Patients with BMI <30 had 10 complications compared with patients with BMI ≥30 had 15 complications. CONCLUSIONS: There are many benefits of fleur-de-lis over traditional panniculectomy, even for medical necessity cases. There is limited undermining of tissue which minimizes/eliminates skin necrosis. Our experience with primarily fleur-de-lis panniculectomies shows a complication rate lower than most published data. Fleur-de-lis potentially creates a better symptom correction and cosmetic outcome by resecting maximal skin in both vertical and horizontal directions. These findings must be balanced against a potentially longer operation.

Adductor magnus perforator flap revisited: an anatomical review and clinical applications.

BACKGROUND: The adductor magnus musculocutaneous perforator flap is a medial thigh flap whose utility is often overshadowed by that of its anatomic neighbor, the gracilis flap. It has a large, reliable pedicle and associated skin paddle. Few reports have been published describing the use of this flap as a local or free tissue transfer. The purpose of this study is to revisit and further characterize the anatomy of this extremely versatile yet underutilized flap. MATERIALS/METHODS: A total of 13 cadavers (n = 26 thighs) were dissected to identify the musculocutaneous perforators that supply the skin of the posteriomedial thigh. The vascular anatomy was studied using multiple modalities. Based on the anatomic data, a local V-Y advancement flap was designed. A total of 8 patients (n = 10 flaps) underwent reconstruction of locoregional defects. RESULTS: Our anatomic studies confirmed the presence of multiple parallel musculocutaneous perforators that travel through the adductor magnus muscle and course obliquely in a posterior-inferior direction. We found that the primary perforator is reliably found approximately 8 cm distal to the groin crease and 2 cm posterior to the posterior border of the gracilis muscle. We discovered that it is consistently accompanied by a separate perforator located 2 cm distally. Minimal dissection into the muscle revealed a Y-configuration of these 2 perforators. This configuration was present in 100% of the cadaveric dissections and is supplied by the first medial branch of the profunda femoris artery. Computed tomography angiograms depicted vascular arborization of the perforators supplying the flap. Clinical experience showed that complete flap survival was achieved in all of the cases. CONCLUSION: The adductor magnus perforator flap is a reliable flap that offers robust blood supply, through a consistent vascular pedicle, to an extensive skin territory. Our anatomic studies revealed the consistent presence of 2 proximal perforators in the medial thigh that are linked by an intramuscular Y-configuration that provides enhanced blood supply to a local V-Y advancement flap design. The location of the skin paddle on the proximal medial thigh allows for minimal donor-site morbidity as it can be closed primarily with a V-Y advancement flap design, obviating the need for skin grafting.

In-hospital mortality after resection of biliary tract cancer in the United States.

OBJECTIVE: To assess perioperative mortality following resection of biliary tract cancer within the U.S. BACKGROUND: Resection remains the only curative treatment for biliary tract cancer. However, current data on operative mortality after surgical resections for biliary tract cancer are limited to small and single-center studies. METHODS: Using the Nationwide Inpatient Sample 1998-2006, a cohort of patient-discharges was assembled with a diagnosis of biliary tract cancer, including intrahepatic bile duct, extrahepatic bile duct, and gall bladder cancers. Patients undergoing resection, including hepatic resection, bile duct resection, pancreaticoduodenectomy, and cholecystectomy, were retained. The primary outcome measure was in-hospital mortality. Categorical variables were analyzed by chi-square. Multivariable logistic regression was performed to identify independent predictors of in-hospital mortality following resection. RESULTS: 31 870 patient-discharges occurred for the diagnosis of biliary tract cancer, including 36.2% intrahepatic ductal, 26.7% extrahepatic ductal, and 31.1% gall bladder. Of the total, 18.6% underwent resection: mean age was 69.3 years (median 70.0); 60.8% were female; 73.7% were white. Overall inpatient surgical mortality was 5.6%. Independently predictive factors of mortality included patient age >/=50 (vs. <50; age 50-59 odds ratio [OR] 5.51, 95% confidence interval [CI] 1.70-17.93; age 60-69 OR 7.25, 95% CI 2.29-22.96; age >/= 70 OR 9.03, 95% CI 2.86-28.56), the presence of identified comorbidities (congestive heart failure, OR 3.67, 95% CI 2.61-5.16; renal failure, OR 4.72, 95% CI 2.97-7.49), and admission designated as emergent (vs. elective; OR 1.82, 95% CI 1.39-2.37). CONCLUSION: Increased in-hospital mortality for patients undergoing biliary tract cancer resection corresponded to age, comorbidity, hospital volume, and emergent admission. Further study is warranted to utilize these observations in promoting early detection, diagnosis, and elective resection.