Tourniquet Use in Extremity-Based Microsurgery.

BACKGROUND: The use of tourniquets and their role in extremity-based microsurgery has not been thoroughly investigated. The purpose of this study was to investigate tourniquet use and its associated outcomes and complications. The authors hypothesize that tourniquets enhance visualization, bloodless approaches to vessel harvest, flap elevation, and anastomosis without added complications. METHODS: A retrospective chart review was completed for patients who had undergone extremity-based microsurgery with the use of a tourniquet between January 2018 and February 2022 at two large academic institutions. Demographic characteristics, initial reasons for surgery, complications, and outcomes were recorded. Patients were separated into groups based on tourniquet use during three operative segments: (1) flap elevation, (2) vessel harvest, and (3) microvascular anastomosis. An internal comparison of complication rate was performed between cases for which a tourniquet was used for one operative segment to all cases in which it was not used for the same operative segment. Univariate and multivariate statistical analyses were performed to identify statistically significant results. RESULTS: A total of 99 patients (106 surgeries) were included in this study across sites. The mean age was 41.2 years and 67.7% of the patients were male. The most common reason for microsurgical reconstruction was trauma (50.5%). The need for an additional unplanned surgery was the most common surgical complication (16%). A total of 70, 61, and 32% of procedures used a tourniquet for flap elevation, vessel harvest, and for anastomosis, respectively. Statistical analyses identified no difference in complication rates for procedures for which a tourniquet was or was not used for interventions. CONCLUSION: Based on these results, the authors state that tourniquets can be utilized for extremity-based microsurgery to enable bloodless dissection without the concern of increased complication rates.

Evaluating the change in patterns of traumatic injury in the setting of pandemic and social distancing restrictions: An analysis of a level 1 trauma center.

BACKGROUND: Social distancing measures and quarantine during the COVID-19 pandemic have led to reported changes in traumatic injury patterns. We set to examine the effects of these restrictive guidelines in our trauma center. METHODS: This is a retrospective chart review of all patients evaluated for traumatic injuries at a Level 1 trauma center during two time periods: March-June 2020 (COVID) and March-June 2019 (Pre-COVID). RESULTS: Overall trauma volume did not differ significantly between the two time periods. Changes seen during COVID included increases in penetrating injuries (12.5% vs 6.7%, p < 0.001), particularly those due to firearms (7.5% vs 3.7%, p < 0.001). Hospital length of stay, intensive care unit length of stay, and days on the ventilator remained consistent between the two groups. Trends toward increased injuries in the home and non-accidental trauma were not statistically significant. CONCLUSION: Traumatic injury patterns have changed as a result of social distancing in both the adult and pediatric trauma populations. Analyzing the effects of social distancing on trauma can lead to a better development of preventive strategies.

Surgical Decision Making in Autologous Fat Grafting: An Evidence-Based Review of Techniques to Maximize Fat Survival.

Autologous fat grafting is an important tool in plastic surgery and is widely used for a variety of applications, both aesthetic and reconstructive. Despite an ever-increasing list of indications and extensive research over many years into improving outcomes, fat grafting remains plagued by incomplete and often unpredictable graft survival. Decisions made at each stage of surgery can potentially contribute to ultimate success, including donor site selection and preparation, fat harvest, processing, and purification of lipoaspirate, recipient site preparation, and delivery of harvested fat to the recipient site. In this review, we examine the evidence for and against proposed techniques at each stage of fat grafting. Areas of consensus identified include use of larger harvesting and grafting cannulas and slow injection speeds to limit cell damage due to shearing forces, grafting techniques emphasizing dispersion of fat throughout the tissue with avoidance of graft pooling, and minimizing exposure of the lipoaspirate to the environment during processing. Safety considerations include use of blunt-tipped needles or cannulas to avoid inadvertent intravascular injection as well as awareness of cannula position and avoidance of danger zones such as the subgluteal venous plexus. We believe that using the evidence to guide surgical decision-making is the key to maximizing fat grafting success. Level of Evidence: 4.

A reconstructive algorithm of oncologic defects of the upper trunk and shoulder girdle: Factors predicting complexity and outcomes.

BACKGROUND: Locally advanced malignancies of the upper torso and shoulder girdle (UT-SG) necessitate extensive resection and complex reconstruction. Due to the infrequent nature of these operations, a global reconstructive algorithm has not been defined. METHODS: A retrospective review of all patients who received reconstructive surgery following malignant tumor extirpation in the UT-SG from 2008 to 2018 at the University of Texas MD Anderson Cancer Center. Factors predicting the need for flap reconstruction and risk for postoperative complications were evaluated. RESULTS: In total, 252 procedures met inclusion criteria. The most common pathology was sarcoma (76%) and 52% were primary tumors. The median defect area was 112 cm2 (range 4-1350 cm2 ). Reconstructive techniques included pedicled flaps (46%), local tissue rearrangement (38%), and free flaps (16%). On univariate analysis, the probability of needing a free flap increased 39% when the defect size increased by 100 cm2 . The strongest independent predictors of requiring a free flap were major vessel exposure (adjusted odds ratio [OR] = 4.92, 95% confidence interval [CI], 1.36-17.84, P = .015) and major peripheral nerve exposure (adjusted OR = 3.2, 95% CI, 1.1-9.2, P = .031). CONCLUSION: Despite the aggressive nature of their malignancies, patients requiring an UT-SG resection demonstrate high survival rates and therefore demand a durable reconstruction. Exposed critical structures and defect size were predictive of free tissue transfer.

Soft-Tissue Reconstruction after Composite Vertebrectomy and Chest Wall Resection for Spinal Tumors.

BACKGROUND: Oncologic resections involving both the spine and chest wall commonly require immediate soft-tissue reconstruction. The authors hypothesized that reconstructions of composite resections involving both the thoracic spine and chest wall would have a higher complication rate than reconstructions for resections limited to the thoracic spine alone. METHODS: The authors performed a retrospective analysis of all consecutive patients who underwent a thoracic vertebrectomy and soft-tissue reconstruction from 2002 to 2017. Patients were divided into two groups: those whose defect was limited to the thoracic spine and those who required a composite resection involving the chest wall. RESULTS: One hundred patients were included. Composite resection patients had larger defects, as indicated by a greater incidence of multilevel vertebrectomies (70.2 percent versus 17 percent; p = 0.001). Thoracic spine patients were older (58.2 ± 10.4 years versus 48.6 ± 13.9 years; p < 0.001) and had a greater incidence of metastatic disease (88.7 percent versus 38.3 percent; p = 0.001). Univariate and multivariate logistic regression analyses demonstrated that composite resections were not significantly associated with a higher rate of surgical, medical, or overall complications. Multivariate logistic regression analysis of composite resection subgroup demonstrated that flap separation of the spinal cord from the intrapleural space was protective against complications (OR, 0.22; 95 percent CI, 0.05 to 0.81; p = 0.03). CONCLUSIONS: Despite the large defect size in composite resection patients, there was no increase in complications compared to thoracic spine patients. In composite resection patients, separating the exposed spinal cord from the intrapleural space with well-vascularized soft tissue was protective against complications. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

Pneumothorax as a Complication of Liposuction.

BACKGROUND: Pneumothorax is a rare complication of liposuction resulting from injury to the lung parenchyma. OBJECTIVES: This study aimed to determine the incidence of pneumothorax complicating liposuction, describe an archetypal presentation, identify risk factors, and propose options for risk reduction. METHODS: In a retrospective chart review, liposuction procedures performed over a 16-year period by 8 surgeons in 1 practice were screened for pneumothorax. Cases featuring pneumothorax were analyzed to ascertain risk factors, presentation, and pathogenesis. RESULTS: Among the 16,215 liposuction procedures performed during the study period, 7 pneumothoraxes were identified (0.0432%). Six (85.7%) were female. Three (42.9%) had previous liposuction. Six cases (85.7%) included liposuction of the axillary region. All cases featured depression of intra/postoperative oxygen saturations as the initial sign. Three (42.9%) were identified intraoperatively. All patients were transferred to a hospital for imaging. Five (71.4%) underwent chest tube placement. Two (28.6%) were treated with observation alone. Pneumothoraxes were left-sided in 4 cases (57.1%), and right-sided in 3 cases (42.9%). In early cases, 1.5-mm infiltration cannulas were used; in 2016 cannula size was changed to 3-4 mm for infiltration and 4-5 mm for liposuction. CONCLUSIONS: Possible risk factors for pneumothorax include liposuction of the axilla, use of flexible infiltration cannulas, and scarring from previous liposuction. We recommend including pneumothorax as a potential complication during informed consent, performing infiltration with a stiff >3.5-mm cannula, minimizing positive-pressure ventilation, emphasized awareness of cannula tip location in all patients but particularly in patients with previous liposuction or scar tissue, and increased caution when operating in the axillary area.

Safety and Efficacy of Smooth Surface Tissue Expander Breast Reconstruction.

BACKGROUND: Traditional 2-stage breast reconstruction involves placement of a textured-surface tissue expander (TTE). Recent studies have demonstrated textured surface devices have higher propensity for bacterial contamination and biofilm formation. OBJECTIVES: The purpose of this study was to evaluate the safety and efficacy of smooth surface tissue expanders (STE) in immediate breast reconstruction. METHODS: The authors retrospectively reviewed consecutive women who underwent STE breast reconstruction from 2016 to 2017 at 3 institutions. Indications and outcomes were evaluated. RESULTS: A total 112 patients underwent STE reconstruction (75 subpectoral, 37 prepectoral placement), receiving 173 devices and monitored for a mean follow-up of 14.1 months. Demographics of patients included average age of 53 years and average BMI of 27.2 kg/m2, and 18.6% received postmastectomy radiation therapy. Overall complication rates were 15.6% and included mastectomy skin flap necrosis (10.4%), seroma (5.2%), expander malposition (2.9%), and infection requiring intravenous antibiotic therapy (3.5%). Six (3.5%) unplanned reoperations with explantation were reported for 3 infections and 3 patients requesting change of plan with no reconstruction. CONCLUSIONS: STEs represent a safe and efficacious alternative to TTE breast reconstruction with at least equitable outcomes. Technique modification including tab fixation, strict pocket control, postoperative bra support, and suture choice may contribute to observed favorable outcomes and are reviewed. Early results for infection control and explantation rate are encouraging and warrant comparative evaluation for potential superiority over TTEs in a prospective randomized trial.

Reconstruction of a Large Anterior Ear Defect after Mohs Micrographic Surgery with a Cartilage Graft and Postauricular Revolving Door Flap.

A novel postauricular revolving door island flap and cartilage graft combination was employed to correct a large defect on the anterior ear of an 84-year-old man who underwent Mohs micrographic surgery for an antihelical squamous cell carcinoma. The defect measured 4.6 × 2.4 cm and spanned the antihelix, scapha, a small portion of the helix, and a large segment of underlying cartilage, with loss of structural integrity and anterior folding of the ear. The repair involved harvesting 1.5 cm(2) of exposed cartilage from the scaphoid fossa and then sculpting and suturing it to the remnant of the antihelical cartilage in order to recreate the antihelical crura. The skin of the posterior auricle was then incised just below the helical rim and folded anteriorly to cover the cartilage graft. The flap remained attached by a central subcutaneous pedicle, and an island designed using the full-thickness defect as a stencil template was pulled through the cartilage window anteriorly to resurface the anterior ear. This case demonstrates the use of the revolving door flap for coverage of large central ear defects with loss of cartilaginous support and illustrates how cartilage grafts may be used in combination with the flap to improve ear contour after resection.

An algorithmic approach to the management of limb ischemia in infants and young children.

BACKGROUND: Vascular injuries in newborns are rare and most commonly occur in the process of obtaining vascular access for monitoring organ system functions or interventions in critical care. Care of vascular injuries in neonates poses several challenges, with the most significant arguably being the lack of clinical experience with such injuries. An algorithm for the management of arterial injuries in pediatric patients is investigated and reported. METHODS: A retrospective chart analysis was performed on all patients consulted for the management of vascular injury by the plastic surgery service at Texas Children's Hospital between 1997 and 2005. The outcomes and procedures were reviewed. RESULTS: Thirty vascular insults in 28 patients were evaluated and treated by the senior author (J.D.F.) using this protocol. Thirty-seven percent (11 of 30) were approached surgically, including two cases treated with thrombolysis alone. The remaining 63 percent (19 of 30) were managed with more conservative interventions, including anticoagulation and clinical optimization. When color Doppler imaging was used preoperatively to locate and describe the characteristics of vascular injuries, visualized lesions coincided with the surgical findings in 100 percent (11 of 11 cases). Twenty-three limbs (77 percent) were salvaged completely using this algorithm, one was initially salvaged but later developed limb-length discrepancy requiring amputation, and one experienced complete limb loss. The remaining patients (five of 30) died as a result of complications of their primary medical conditions before limb salvage could be assessed. CONCLUSION: This evaluation demonstrates the efficacy of the proposed algorithm used to determine direction of care in the event of arterial injury in small children.

Synthetic materials in the study of cell response to substrate rigidity.

While it has long been understood that cells can sense and respond to a variety of stimuli, including soluble and insoluble factors, light, and externally applied mechanical stresses, the extent to which cells can sense and respond to the mechanical properties of their environment has only recently begun to be studied. Cell response to substrate stiffness has been suggested to play an important role in processes ranging from developmental morphogenesis to the pathogenesis of disease states and may have profound implications for cell and tissue culture and tissue engineering. Given the importance of this phenomenon, there is a clear need for systems for cell study in which substrate mechanics can be carefully defined and varied independently of biochemical and other signals. This review will highlight past work in the field of cell response to substrate rigidity as well as areas for future study.

PEGDA hydrogels with patterned elasticity: Novel tools for the study of cell response to substrate rigidity.

The ability of cells to migrate in response to mechanical gradients (durotaxis) and differential cell behavior in adhesion, spreading, and proliferation in response to substrate rigidity are key factors both in tissue engineering, in which materials must be selected to provide the appropriate mechanical signals, and in studies of mechanisms of diseases such as cancer and atherosclerosis, in which changes in tissue stiffness may inform cell behavior. Using poly(ethylene glycol) diacrylate hydrogels with varying polymer chain length and photolithographic patterning techniques, we are able to provide substrates with spatially patterned, tunable mechanical properties in both gradients and distinct patterns. The hydrogels can be patterned to produce anisotropic structures and exhibit patterned strain under mechanical loading. These hydrogels may be used to study cell response to substrate rigidity in both two and three dimensions and can also be used as a scaffold in tissue-engineering applications.