David B. Drake

Quantifying bacterial bioburden during negative pressure wound therapy: does the wound VAC enhance bacterial clearance?

The bacterial colonization of a wound is a recognized detrimental factor in the multifactorial process of wound healing. The harmful effects on wound healing are recognized to correspond to a level of >105 colonies of bacteria per gram of tissue. Negative pressure wound therapy has become an accepted treatment modality for acute and chronic wounds with accelerated healing rates observed. It has been previously reported that this therapy enhances bacterial clearance, which may account for the wound healing effects noted. We retrospectively reviewed 25 patients’ charts undergoing Wound VAC (Vacuum Assisted Closure Device; KCI International, San Antonio, TX) therapy with serial quantitative cultures and found that there is not a consistent effect of bacterial clearance with the Wound VAC. Furthermore, bacterial colonization increased significantly with Wound VAC therapy and remained in a range of 104–106. Despite this finding, the beneficial effects of this treatment modality on wound healing were noted in most cases.

Wound complications of abdominoplasty in obese patients

The records of 90 patients who underwent an abdominoplasty at the University of Virginia Health Sciences Center were analyzed to determine the effect of obesity on the incidence of complications after this surgery. The study patients were divided into three groups-obese, borderline, and nonobese-based on the degree to which their preoperative weights varied from their ideal body weight. A history of previous bariatric surgery was also analyzed to determine what impact that might have on subsequent abdominoplasty. Results showed that 80% of obese patients had complications compared with the borderline and nonobese patients, who had complication rates of 33% and 32.5% respectively (p = 0.001). Previous gastric bypass surgery had no significant effect on the incidence of postabdominoplasty complications. Based on these findings the authors conclude that obesity at the time of abdominoplasty has a profound influence on the wound complication rate following surgery, regardless of any previous weight reduction surgery.

An Outcome Study of Breast Reconstruction: Presurgical Identification of Risk Factors for Complications

Background: Breast reconstruction following mastectomy has been shown to have a salutary effect on the overall psychological well-being of women being treated for breast cancer. Unfortunately, however, not every patient is an ideal candidate for reconstruction. Complications stemming from reconstructive surgery can cause significant morbidity, the most important of which may be the delay of subsequent adjuvant antineoplastic therapies, and therefore may not be in the best interests of the patient.Methods: A retrospective study was performed on a consecutive series of 123 breast reconstructions in 98 patients, performed by one of two plastic surgeons, in a university setting over a 5-year period, for all surgical outcomes. Specifically, wound-healing complications, infections, and reoperations leading to the potential delay of subsequent chemotherapy or radiotherapy were recorded, and possible risk factors leading to these were sought.Results: Three presurgical risk factors were found to have a statistically significant influence on the development of complications following breast reconstruction. These were: (1) increasing obesity, defined by the body mass index, (2) an active or recent (<5 year) history of cigarette smoking, and (3) a history of previous radiation exposure. Odds ratios were used to describe the magnitude of the effect of each factor for the development of complications. An ordinal regression analysis was used to create a nomogram based on this information that can be used to calculate any individual patient’s presurgical risk for developing major complications following breast reconstruction, based on the presence of these factors.Conclusions: It is possible, based on the presence of specific presurgical risk factors, to predict the probability of developing major complications following breast reconstruction. This information can be useful to the referring physician and plastic surgeon alike in determining which patients are the best candidates for breast reconstruction and which type of reconstruction would be best suited for each individual patient.

The vacuum-assisted closure device as a bridge to sternal wound closure.

Sixteen patients were treated for sternal wound infections after undergoing cardiac procedures. Their management involved prompt surgical debridement and quantitative wound biopsies. At the time of the initial debridement, the Vacuum-Assisted Closure Device (V.A.C.) was placed in the open sternal wound. A subatmospheric environment was maintained by the device at a level of 75 to 150 mmHg. The V.A.C. sponge was changed every 2 to 3 days, and operative debridement was performed until quantitative biopsies showed resolution of infection or until systemic signs of sepsis had resolved. At this time the sternal wounds were closed with regional muscle flaps. Patients were excluded from the use of the device if the pleural cavity was entered during operative debridement. Fifteen of the 16 patients survived and went on to complete wound healing and discharge from the hospital (average length of stay, 16.7 days). One patient sustained a cardiac dysrhythmia during the muscle flap procedure and died. There were no complications related directly to the use of the V.A.C. It is the opinion of the authors that the V.A.C. offers several advantages over their traditional methods of treatment. They noted improvement in sternal wound stabilization during the perioperative period and a decreased need for paralysis and mechanical ventilation. Wound management was improved by avoiding the need to perform debridement or to make desiccating dressing changes to an open sternum. Moreover, they also think that this device may lessen the risk for ventricular rupture because of better control of the wound environment and markedly improved stabilization of the debrided sternal elements.

Comparison study of two types of expander-based breast reconstruction: acellular dermal matrix-assisted versus total submuscular placement.

AbstractRecent reported complications have called some authors to express concern regarding the increased popularity of acellular dermal matrix (ADM)-based breast reconstruction, and its role as an alternative to traditional total submuscular approaches. To address this issue, we compared tissue expansion properties, complication rates, and patient satisfaction for both operative techniques at the same institution. A retrospective review was completed on 75 patients and 100 tissue expander/implant-based breast reconstructions at a single academic institution from 2007 to 2010. Of these cases, 31 patients were reconstructed with ADM and 44 with a submuscular coverage technique. Total complications including seroma, hematoma, infection, skin necrosis, and explantation did not significantly differ between groups (n = 13 for ADM vs. 17 for submuscular, P = 0.814). Consistent with prior reports, ADM-based reconstructions were associated with significantly increased intraoperative fill volumes and lower total number of sessions to achieve final volume. Submuscular reconstructions required a significantly higher tissue expander fill volume. Eight patients in the submuscular group required surgical revision of the breast and inframammary fold, compared with 4 in the ADM group; however, this difference was not significant. Patient satisfaction was equivalent between the 2 groups; however, it was higher in patients with bilateral reconstruction and lower among those who had received adjuvant radiation therapy. Satisfaction with nipple reconstruction was inversely proportional to time elapsed from the procedure to survey conduction. This is the first study to perform a head-to-head comparison on the basis of patient satisfaction, the results of which may be useful in preoperative planning and counseling.

REVOLUTIONARY ADVANCES IN THE MANAGEMENT OF TRAUMATIC WOUNDS IN THE EMERGENCY DEPARTMENT DURING THE LAST 40 YEARS: PART I

BACKGROUND AND OBJECTIVES This report provides an overview of advances in wound repair devised by our research team during the last four decades. This collective review is presented in two parts. DISCUSSION The following components are included in Part I: 1) search and treat life-threatening trauma; 2) conduct a thorough history; 3) examine the wound using aseptic technique; 4) anesthetize the wound before cleansing; 5) hair removal, skin disinfection, hemostasis, surgical debridement, and mechanical cleansing; 6) antibiotics, drains, and open wound management. CONCLUSION On the basis of these comprehensive research studies, we have noted a marked reduction in the incidence of wound infection in traumatic wounds.

comparison of the Thrombogenicity of Internationally Available Fibrin Sealants in an Established Microsurgical Model

Previous studies comparing the thrombotic complications of cryoprecipitated fibrin sealant containing bovine thrombin on microvascular venous anastomoses in a rat epigastric free flap model revealed deleterious outcomes regarding flap survival with higher concentrations of topical bovine thrombin. This study was designed to compare three internationally available fibrin sealants, one experimental fibrin monomer sealant that does not require thrombin, and human thrombin alone as to their effects on the survival of an established rat epigastric free flap model. Ninety Sprague-Dawley rats (400 to 600 g) were prepared for abdominal surgery, and an epigastric-based skin flap was raised. The single vein draining the flap was clamped, divided, and reconnected using standard microvascular suturing techniques. Before release of the clamps, the chosen additive was applied precisely to the anastomosis. Additional material was then added to the raw surface of the flap. The animals were divided into seven treatment groups, each receiving 1 ml of commercial or investigational fibrin sealant or human thrombin alone: one control group receiving no additive treatment, four fibrin sealant groups receiving treatment with commercial or investigational fibrin sealant preparations, and two groups receiving different concentrations (500 IU/ml and 1000 IU/ml) of human thrombin applied to the anastomoses and the surrounding tissue. Flap survival was assessed at 7 days postoperatively. This study supports the contention that microvascular free flap survival based on microvascular venous anastomotic patency was adversely effected by high concentrations of thrombin. Lower concentrations (500 IU/ml and less) of thrombin did not seem to affect flap survival. One test product was composed of a fibrin monomer sealant, which obviates the need for the thrombin additive. This groups survival rate was not statistically different from that of the control group. Thus, for microvascular anastomoses, lower concentrations of thrombin or a sealant devoid of thrombin seem to be best for microvascular anastomotic patency.

Acute Thrombogenic Effects of Fibrin Sealant on Microvascular Anastomoses in a Rat Model

Topically applied bioadhesives and hemostatic agents have gained wide acceptance in various surgical endeavors. However, the effect of thrombin-based fibrin sealant (fibrin glue) when applied to microvascular anastomoses has not been evaluated thoroughly. Although fibrin sealant has been used directly on vascular anastomoses in macrovascular surgery, there has been little exploration into the utility and potential complications when used in the microsurgical setting. This study explored the influence of fibrin sealant containing increasing concentrations of bovine thrombin on microvascular anastomoses in a rat epigastric free flap model. The survival of the free flap in this model appeared to be inversely proportional to the concentration of thrombin in the fibrin sealant. When thrombin alone was applied to the anastomoses, the rate of thrombosis was the highest. Venous anastomosis was the most sensitive to the deleterious effects of topically applied thrombin.

Evaluation of Host Tissue Integration, Revascularization, and Cellular Infiltration Within Various Dermal Substrates

Acellular dermal matrices are used in a variety of reconstructive and cosmetic procedures. There seems to be host tissue integration, revascularization, and recellularization into these products, but the exact timing and differences among these remain unknown. The purpose of this study is to determine and compare these properties of 4 different acellular dermal matrices (AlloDerm, DermACELL, DermaMatrix, and Integra) in an in vivo rat model. Tissue specimens were obtained at various time points. Histology and immunohistologic assays were used to quantify the extent of cellular infiltration and revascularization within the various matrices. A bimodal cellular response was observed in all products except for DermACELL. Cellular infiltration was highest in DermACELL and lowest in AlloDerm, and angiogenesis was evident by day 7. There were clear differences within the various products. It is undetermined whether these differences are advantageous or clinically significant. Future work is needed to define the specific roles for each.

Hemostatic effect of Vivostat patient-derived fibrin sealant on split-thickness skin graft donor sites.

Topical hemostatic agents are used frequently to control bleeding of skin graft donor sites. In this study, the hemostatic properties of Vivostat (Vivolution A/S, Birkerød, Denmark) patient-derived fibrin sealant were compared with a control group of spray thrombin solution, which is considered an industry standard for topical hemostasis. Treatments were applied simultaneously to two randomly chosen halves of a single split-thickness single donor site in patients in five United States surgical centers. The time to achieve satisfactory hemostasis (≤10 min) was estimated on each half of the wound as the time at which active bleeding had stopped and the wound was suitable for application of a surgical dressing. The time to hemostasis of wounds treated with Vivostat (Vivolution A/S) patient-derived sealant was significantly shorter in comparison with wounds treated with thrombin solution (medians: Vivostat, 31 seconds; thrombin, 58 seconds;p = 0.0012). No abnormalities in wound healing were reported for either treatment site 1 week after the operation. Vivostat (Vivolution A/S) sealant is a more rapidly effective topical hemostatic agent than thrombin on split-thickness skin graft donor sites.