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BACKGROUND: Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare complication associated with the use of breast implants. Breast implant illness (BII) is another potentially concerning issue related to breast implants. This study aims to assess the quality of ChatGPT as a potential source of patient education by comparing the answers to frequently asked questions on BIA-ALCL and BII provided by ChatGPT and Google. METHODS: The Google and ChatGPT answers to the 10 most frequently asked questions on the search terms "breast implant associated anaplastic large cell lymphoma" and "breast implant illness" were recorded. Five blinded breast plastic surgeons were then asked to grade the quality of the answers according to the Global Quality Score (GQS). A Wilcoxon paired t-test was performed to evaluate the difference in GQS ratings for Google and ChatGPT answers. The sources provided by Google and ChatGPT were also categorized and assessed. RESULTS: In a comparison of answers provided by Google and ChatGPT on BIA-ALCL and BII, ChatGPT significantly outperformed Google. For BIA-ALCL, Google's average score was 2.72 ± 1.44, whereas ChatGPT scored an average of 4.18 ± 1.04 (p < 0.01). For BII, Google's average score was 2.66 ± 1.24, while ChatGPT scored an average of 4.28 ± 0.97 (p < 0.01). The superiority of ChatGPT's responses was attributed to their comprehensive nature and recognition of existing knowledge gaps. However, some of ChatGPT's answers had inaccessible sources. CONCLUSION: ChatGPT outperforms Google in providing high-quality answers to commonly asked questions on BIA-ALCL and BII, highlighting the potential of AI technologies in patient education. LEVEL OF EVIDENCE: Level III, comparative study LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Implantación de Mama , Implantes de Mama , Neoplasias de la Mama , Linfoma Anaplásico de Células Grandes , Cirujanos , Humanos , Femenino , Implantes de Mama/efectos adversos , Linfoma Anaplásico de Células Grandes/epidemiología , Linfoma Anaplásico de Células Grandes/etiología , Linfoma Anaplásico de Células Grandes/patología , Motor de Búsqueda , Implantación de Mama/efectos adversos , Fuentes de Información , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Neoplasias de la Mama/cirugíaRESUMEN
BACKGROUND: Immediate implant-based breast reconstruction (IIBR) is the most commonly used method in breast reconstruction in the United States. However, postoperative surgical site infections (SSIs) can cause devastating reconstructive failure. This study evaluates the use of perioperative versus extended courses of antibiotic prophylaxis after IIBR for the prevention of SSI. METHODS: This is a single-institution retrospective study of patients who underwent IIBR between June 2018 and April 2020. Detailed demographic and clinical information was collected. Patients were divided into subgroups based on antibiotic prophylaxis regimen: group 1 consisted of patients who received 24 hours of perioperative antibiotics and group 2 consisted of patients who received ≥7 days of antibiotics. Statistical analyses were conducted using SPSSv26.0 with P ≤ 0.05 considered statistically significant. RESULTS: A total of 169 patients (285 breasts) who underwent IIBR were included. The mean age was 52.4 ± 10.2 years, and the mean body mass index (BMI) was 26.8 ± 5.7 kg/m2. Twenty-five percent of patients (25.6%) underwent nipple-sparing mastectomy, 69.1% skin-sparing mastectomy, and 5.3% total mastectomy. The implant was placed in the prepectoral, subpectoral, and dual planes in 16.7%, 19.2%, and 64.1% cases, respectively. Acellular dermal matrix was used in 78.7% of cases. A total of 42.0% of patients received 24-hour prophylaxis (group 1), and 58.0% of patients received extended prophylaxis (group 2). Twenty-five infections (14.8%) were identified, of which 9 (5.3%) resulted in reconstructive failure. In bivariate analyses, no significant difference was found between groups in rates of infection (P = 0.273), reconstructive failure (P = 0.653), and seroma (P = 0.125). There was a difference in hematoma rates between groups (P = 0.046). Interestingly, in patients who received only perioperative antibiotics, infection rates were significantly higher in those with BMI ≥ 25 (25.6% vs 7.1%, P = 0.050). There was no difference in overweight patients who received extended antibiotics (16.4% vs 7.0%, P = 0.160). CONCLUSIONS: Our data demonstrate no statistical difference in infection rates between perioperative and extended antibiotics. This suggests that the efficacies of current prophylaxis regimens are largely similar, with choice of regimen based on surgeon preference and patient-specific considerations. Infection rates in patients who received perioperative prophylaxis and were overweight were significantly higher, suggesting that BMI should be taken into consideration when choosing a prophylaxis regimen.
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Dermis Acelular , Implantación de Mama , Implantes de Mama , Neoplasias de la Mama , Mamoplastia , Humanos , Adulto , Persona de Mediana Edad , Femenino , Mastectomía , Profilaxis Antibiótica , Estudios Retrospectivos , Neoplasias de la Mama/cirugía , Sobrepeso , Mamoplastia/métodos , Antibacterianos/uso terapéutico , Implantación de Mama/métodosRESUMEN
BACKGROUND: Venous thromboembolism (VTE) is a serious complication, particularly in cancer patients undergoing free flap reconstruction. Subcutaneous enoxaparin is the conventional prophylaxis for VTE prevention, and serum anti-factor Xa (afXa) levels are being increasingly used to monitor enoxaparin activity. In this study, free flap patients receiving standard enoxaparin prophylaxis were prospectively followed to investigate postoperative afXa levels and 90-day VTE and bleeding-related complications. METHODS: Patients undergoing free tissue transfer during an 8-month period were identified and prospectively followed. Patients received standard fixed enoxaparin dosing at 30 mg twice daily in head and neck (H&N) and 40 mg daily in breast reconstructions. Target peak prophylactic afXa range was 0.2 to 0.5 IU/mL. The primary outcome was the occurrence of 90-day postoperative VTE- and bleeding-related events. Independent predictors of afXa level and VTE incidence were analyzed for patients that met the inclusion criteria. RESULTS: Seventy-eight patients were prospectively followed. Four (5.1%) were diagnosed with VTE, and six (7.7%) experienced bleeding-related complications. The mean afXa levels in both VTE patients and bleeding patients were subprophylactic (0.13 ± 0.09 and 0.11 ± 0.07 IU/mL, respectively). Forty-six patients (21 breast, 25 H&N) had valid postoperative peak steady-state afXa levels. Among these, 15 (33%) patients achieved the target prophylactic range: 5 (33%) H&N and 10 (67%) breast patients. The mean afXa level for H&N patients was significantly lower than for breast patients (p = 0.0021). Patient total body weight was the sole negative predictor of afXa level (R 2 = 0.47, p < 0.0001). CONCLUSION: Standard fixed enoxaparin dosing for postoperative VTE prophylaxis does not achieve target afXa levels for the majority of our free flap patients. H&N patients appear to be a particularly high-risk group that may require a more personalized and aggressive approach. Total body weight is the sole negative predictor of afXa level, supporting a role for weight-based enoxaparin dosing.
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Colgajos Tisulares Libres , Tromboembolia Venosa , Humanos , Enoxaparina/uso terapéutico , Tromboembolia Venosa/tratamiento farmacológico , Anticoagulantes/uso terapéutico , Peso CorporalRESUMEN
Background Desirable candidate characteristics for microsurgery fellowship applicants still remain unclear, as no data are available in the literature. This study aims to provide information on the criteria that are used to select and rank applicants for the microsurgery fellowship match. Methods A 38-question survey was sent in April 2015 to all microsurgery fellowship directors (n = 36) involved in the U.S. match, using QuestionPro Software. The survey investigated various factors used for selection of applicants, including medical school, residency training, research experience, fellowship interview, and candidate characteristics. A 5-point Likert scale was used to grade 33 influential factors from 1 ("not at all important in making my decision") to 5 ("essential in making my decision"), or for 5 controversial factors from 1 ("very negative impact in making my decision") to 5 ("very positive impact in making my decision"). Results A total of 53% (19 out of 36) of responses were received from microsurgery fellowship directors. The most important factors included letters of recommendations by microsurgeons (4.6 ± 0.5), interactions with faculty (4.6 ± 0.5), overall interview performance in the selection process (4.6 ± 0.5), and professionalism and ethics (4.4 ± 0.7). Factors that had a negative impact on the selection process included graduate from a non-U.S. plastic surgery residency program (2.1 ± 0.9), graduate needing a visa (2.3 ± 0.8), and graduate from a foreign medical school (2.4 ± 1.0). Conclusion This study provides data on the microsurgery fellowship directors' perception of the criteria important for applicant selection and shows that the most valued criteria are letters of recommendation, interactions with faculty, and interview performance.
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Educación de Postgrado en Medicina , Becas , Microcirugia/educación , Ejecutivos Médicos , Criterios de Admisión Escolar , Encuestas y Cuestionarios , Humanos , Rol del Médico , Cirugía Plástica/educación , Estados Unidos , Recursos HumanosRESUMEN
BACKGROUND: Despite evidence that reduction mammaplasty alleviates macromastia symptoms independent of resection weights, resection minimums are commonly used to grant insurance coverage. Multiple formulas have been published to predict resection weights, but very few have evaluated predictive performance relative to attaining common insurance minimums. METHODS: This was a retrospective single-center review of 268 patients from 2007 to 2020. Multiple linear regression and exponential models were created to predict resection weights and attainment of the Schnur, 350-g, and 500-g minimums. Accuracy was compared against published Appel, Descamps, and Galveston equations. Body mass index subgroup analyses were performed. RESULTS: The exponential model possessed the lowest resection weight prediction error overall (172.8 ± 211.5 g). All equations performed significantly better than surgeons in predicting attainment of the 500-g minimum. None performed better than the surgeons' predictive accuracy in attaining a 350-g minimum. Multiple linear regression and exponential models performed significantly better than surgeons in predicting attainment of the Schnur minimum. Only the exponential model performed significantly better than surgeons for both the Schnur (82% versus 71%; P < 0.01) and the 500-g minimums (89% versus 68%; P < 0.01). On body mass index subgroup analyses, all three minimums were biased in favor of obese women-the least egregious of these was the 350-g minimum. CONCLUSIONS: All minimums were biased against nonobese women. Our exponential model equation based on preoperative sternal notch-to-nipple and nipple-to-inframammary fold distances accurately predicts resection weights and improves on our surgeons' predictive accuracy in attaining the Schnur or 500-g minimums. This may prove useful in the preoperative setting to better counsel patients.
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Mamoplastia , Femenino , Humanos , Estudios Retrospectivos , Pezones/cirugía , Índice de Masa Corporal , Cobertura del Seguro , Hipertrofia/cirugíaRESUMEN
Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a variant of anaplastic large cell lymphoma (ALCL) associated with textured-surface silicone breast implants. Since first being described in 1997, over 1100 cases have been currently reported worldwide. A causal relationship between BIA-ALCL and textured implants has been established in epidemiological studies, but a multifactorial process is likely to be involved in the pathogenesis of BIA-ALCL. However, pathophysiologic mechanisms remain unclear. One of the hypotheses that could explain the link between textured implants and BIA-ALCL consists in the greater tendency of bacterial biofilm in colonizing the surface of textured implants compared to smooth implants, and the resulting chronic inflammation which, in predisposed individuals, may lead to tumorigenesis. This review summarizes the existing evidence on the role of micro-organisms and rough surface implants in the development of BIA-ALCL. It also provides insights into the most updated clinical practice knowledge about BIA-ALCL, from clinical presentation and investigation to treatment and outcomes.
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Necrosis of the nipple-areolar complex (NAC) or surrounding skin has been reported in 6%-30% of nipple-sparing mastectomy (NSM) patients, with higher rates associated with larger breasts, previous breast surgery, previous radiation, and active smoking. The nipple delay (ND) procedure is known to improve viability of the NAC in NSM patients with high-risk factors. Methods: A single-institution retrospective review was done of patients who underwent ND and NSM or NSM alone from 2012 to 2022. Patient demographics, risk factors, and outcomes were compared. Results: Forty-two breasts received ND-NSM and 302 breasts received NSM alone. The ND-NSM group had significantly more high-risk factors, including elevated BMI (26.3 versus 22.9; P < 0.001), elevated prior breast surgery (50% versus 25%; P < 0.001), and greater mastectomy specimen weight (646.6 versus 303.2 g; P < 0.001). ND-NSM was more likely to have undergone preparatory mammoplasty before NSM (27% versus 1%; P < 0.001). There was no delay in NSM treatment from decision to pursue NSM (P = 0.483) or difference in skin necrosis (P = 0.256), NAC necrosis (P = 0.510), hematoma (P = 0.094), seroma (P = 0.137), or infection (P = 0.437) between groups. ND-NSM and NSM patients differed in total NAC necrosis (0% versus 3%) and implant loss (0% vs 13%), but not significantly. Conclusions: We demonstrated no NAC necrosis and no significant delay of treatment in higher risk ND-NSM patients. ND may allow higher risk patients to undergo NSM with similar morbidity as lower risk patients.
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OBJECTIVE: Up to 10% of free flap cases are compromised, and without prompt intervention, amputation and even death can occur. Hourly monitoring improves salvage rates, but the gold standard for monitoring requires experienced personnel to operate and suffers from high false-positive rates as high as 31% that result in costly and unnecessary surgeries. In this paper, we investigate free flap patency monitoring using automatic hardware-only classification systems that eliminate the need for experienced personnel. The expected flow ranges of the antegrade and retrograde veins for breast reconstruction are studied using a syringe pump to create the laminar flow seen in veins. METHODS: Feature data extracted from the Doppler blood flow signals are analyzed for sensitivity, specificity, and false-positive rates. Hardware is built to perform the classification automatically in real-time and output a decision at the end of the observation period. RESULTS: Experimental results using the hardware-only classifier for a 50 ms window size show high sensitivity (96.75%), specificity (90.20%), and low false-positive rate (9.803%). The experimental and theoretical classification results show close agreement. CONCLUSION: This work indicates that automatic hardware-only classifiers can eliminate the need for experienced personnel to monitor free flap patency. SIGNIFICANCE: The hardware-only classification is amenable to a monolithic implementation and future studies should study a totally implantable wirelessly-powered blood flow classifier. The high classifier performance in a short window period indicates that duty-cycled powering can be used to extend the safe operational depth of an implant. This is particularly relevant for the difficult buried free flap applications.
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Colgajos Tisulares Libres , Monitoreo Fisiológico/instrumentación , Prótesis e Implantes , Procesamiento de Señales Asistido por Computador , Ultrasonografía Doppler/instrumentación , Simulación por Computador , Bases de Datos Factuales , Diseño de Equipo , Colgajos Tisulares Libres/efectos adversos , Colgajos Tisulares Libres/irrigación sanguínea , Humanos , Procedimientos de Cirugía Plástica , Grado de Desobstrucción VascularRESUMEN
PURPOSE: Although abdominal-based flaps remain the first choice for autologous breast reconstruction, alternative donor sites are necessary when the abdomen is unavailable. Abdominal donor site suitability is determined, at times, according to deep inferior epigastric perforator (DIEP)-protocol computed tomographic angiography (CTA) results. CTA provides information about the pelvis/upper thigh that can be used to evaluate the suitability of other donor sites. This study aimed to examine the utility of DIEP-protocol CTA in the assessment of a lateral thigh perforator (LTP) flap. Furthermore, a small clinical LTP flap breast reconstruction series was presented. METHODS: The LTP flap anatomy was studied in 100 DIEP-protocol CT angiographies (200 thighs). Collected data included lateral circumflex femoral artery (LCFA) origin; number, type, and course of LTPs; pedicle characteristics; and reference point measurements. Relative relationships between reference point anatomy and perforator anatomy were analyzed. RESULTS: Perforators originated from the LCFA ascending branch (4.6 mm average diameter), averaging 2.6 perforators/thigh. The mean estimated pedicle length was 7.7 cm (±0.7 cm). Septocutaneous perforators were present in 97% (1.8 perforators/thigh). Musculocutaneous perforators were present in 64% (0.9 perforators/thigh). The mean distance between anterior superior iliac spine and perforator was 9.9 cm (±1.5 cm). Perforators were located 0.13 cm (±1.1 cm) below the pubic symphysis. Our LTP flap clinical series featured dissection in the supine position and primary donor site closure and highlighted the difficulty in flap design (six patients, nine LTP flaps). CONCLUSIONS: LTPs are consistent, reliably present, and radiographically appear to be suitable for microsurgical transfer. DIEP-protocol CTA is an acceptable method for imaging the pertinent LTP anatomy.
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Mamoplastia/métodos , Colgajo Perforante/irrigación sanguínea , Anciano , Aloinjertos/irrigación sanguínea , Aloinjertos/diagnóstico por imagen , Puntos Anatómicos de Referencia , Angiografía por Tomografía Computarizada , Femenino , Arteria Femoral/diagnóstico por imagen , Humanos , Microcirugia/métodos , Persona de Mediana Edad , Muslo , Sitio Donante de Trasplante/irrigación sanguíneaRESUMEN
Totally implantable wireless ultrasonic blood flowmeters provide direct-access chronic vessel monitoring in hard-to-reach places without using wired bedside monitors or imaging equipment. Although wireless implantable Doppler devices are accurate for most applications, device size and implant lifetime remain vastly underdeveloped. We review past and current approaches to miniaturization and implant lifetime extension for wireless implantable Doppler devices and propose approaches to reduce device size and maximize implant lifetime for the next generation of devices. Additionally, we review current and past approaches to accurate blood flow measurements. This review points toward relying on increased levels of monolithic customization and integration to reduce size. Meanwhile, recommendations to maximize implant lifetime should include alternative sources of power, such as transcutaneous wireless power, that stand to extend lifetime indefinitely. Coupling together the results will pave the way for ultra-miniaturized totally implantable wireless blood flow monitors for truly chronic implantation.
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Flujómetros , Miniaturización/instrumentación , Prótesis e Implantes , Flujo Sanguíneo Regional/fisiología , Ultrasonografía Doppler/instrumentación , Tecnología Inalámbrica/instrumentación , Diseño de Equipo , Humanos , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: Skin-sparing mastectomy designs for immediate autologous breast reconstruction include racquet, Wise, and vertical mammaplasty incisions. The vertical design addresses ptosis while maintaining viable skin flaps. This study compares the racquet to the vertical incision. METHODS: Immediate skin-sparing autologous breast reconstructions by a single surgeon using either vertical or racquet incisions from August 2006 to September 2011 were analyzed. Aesthetic scoring was based on a Likert-scale assessment of scar appearance, shape, preoperative versus postoperative aesthetic comparison, and overall aesthetic outcome. Responses were analyzed using the Mann-Whitney test. RESULTS: Seventy-seven patients (48 racquets and 29 vertical) were included. Patient demographics and complications did not differ. Vertical design reconstructions were used for patients with higher-grade ptosis (p < 0.001). Significantly better-appearing scars (3.8 vs. 3.5; p = 0.04) were observed in the vertical group. Vertical reconstructions showed a trend toward significance in cosmetic improvement compared with preoperative appearance (3.2 vs. 3.0; p = 0.06). There was no difference in shape (vertical 3.6, racquet 3.6; p = 0.86) or in postoperative aesthetic result (vertical 3.6, racquet 3.4; p = 0.41). CONCLUSIONS: Shape and overall postoperative aesthetic appearance did not significantly differ despite greater ptosis preoperatively in the vertical group, demonstrating the efficacy of the vertical design in reconstruction. Vertical design reconstructions were rated aesthetically superior to their pre-mastectomy appearance. Significantly better scar scores in the vertical group reflect the camouflaged nature of vertical incisions. These results demonstrate that the aesthetic outcome of the vertical design reconstruction in ptotic breasts is as good as and potentially superior to the racquet design reconstruction in non-ptotic breasts.
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Neoplasias de la Mama/cirugía , Mamoplastia/métodos , Mastectomía/métodos , Trasplante de Piel/métodos , Colgajos Quirúrgicos , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Satisfacción del Paciente , Estudios Retrospectivos , Trasplante Autólogo , Resultado del TratamientoRESUMEN
Current totally implantable wireless blood flow monitors are large and cannot operate alongside nearby monitors. To alleviate the problems with the current monitors, we developed a system to monitor blood flow wirelessly, with a simple and easily interpretable real-time output. To the best of our knowledge, the implanted electronics are the smallest in reported literature, which reduces bio-burden. Calibration was performed across realistic physiological flow ranges using a syringe pump. The device's sensors connected directly to the bilateral femoral veins of swine. For each 1 min, blood flow was monitored, then, an occlusion was introduced, and then, the occlusion was removed to resume flow. Each vein of four pigs was monitored four times, totaling 32 data collections. The implant measured 1.70 cm3 without battery/encapsulation. Across its calibrated range, including equipment tolerances, the relative error is less than ±5% above 8 mL/min and between -0.8% and +1.2% at its largest calibrated flow rate, which to the best of our knowledge is the lowest reported in the literature across the measured calibration range. The average standard deviation of the flow waveform amplitude was three times greater than that of no-flow. Establishing the relative amplitude for the flow and no-flow waveforms was found necessary, particularly for noise modulated Doppler signals. Its size and accuracy, compared with other microcontroller-equipped totally implantable monitors, make it a good candidate for future tether-free free flap monitoring studies.
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Microvascular anastomotic failure remains an uncommon but devastating problem. Although the implantable Doppler probe is helpful in flap monitoring, the devices are cumbersome, easily dislodged, and plagued by false-positive results. The authors have developed an implantable wireless Doppler monitor prototype from off-the-shelf components and tested it in a swine model. The wireless probe successfully distinguished between femoral vein flow, occlusion, and reflow, and wirelessly reported the different signals reliably. This is the first description of a wireless implantable blood flow sensor for flap monitoring. Future iterations will incorporate an integrated microchip-based Doppler system that will decrease the size to 1 mm, small enough to fit onto an anastomotic coupler.
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Vena Femoral/fisiología , Hemorreología , Monitoreo Fisiológico/instrumentación , Prótesis e Implantes , Colgajos Quirúrgicos/irrigación sanguínea , Ultrasonografía Doppler/instrumentación , Tecnología Inalámbrica , Animales , Diseño de Equipo , Femenino , PorcinosRESUMEN
BACKGROUND: Venous thromboembolism continues to be problematic despite increased recognition and advancements in venous thromboembolism prophylaxis. Although migration toward preoperative chemoprophylaxis increases, plastic surgeons seem reticent to adopt this practice. This study evaluates preoperative enoxaparin administration in breast reconstruction patients. METHODS: Patients undergoing breast reconstruction performed by a single surgeon over a 5-year period were evaluated retrospectively. The authors introduced preoperative chemoprophylaxis with enoxaparin in all breast reconstructions during this time. Prosthetic-based and microsurgical breast reconstructions were examined. Patients were divided into two groups: those who did and those who did not receive preoperative enoxaparin. The authors reviewed patient demographics, comorbidities, and complications, focusing on bleeding complications. RESULTS: Three hundred patients (450 breasts) were included. One hundred fifty-four patients (244 breasts) underwent reconstruction with tissue expanders, and 146 (206 breasts) underwent free flap reconstructions. One hundred seventy-nine of 300 were given preoperative enoxaparin. Eleven hematomas occurred, eight (4.5 percent) in the enoxaparin group and three (2.5 percent) without enoxaparin (p = 0.399). Blood transfusions were given to four patients (2.2 percent) who received enoxaparin and one patient (0.8 percent) who did not (p = 0.652). Finally, any type of bleeding complication occurred in 11 patients (6.1 percent) with enoxaparin and in four (3.3 percent) without (p = 0.419). Larger breasts were more likely to receive enoxaparin (p = 0.011), which did not result in higher bleeding complications. CONCLUSION: In this retrospective study, the authors found that preoperative chemoprophylaxis in breast reconstruction was associated with an acceptable rate of postoperative bleeding complications. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.
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Anticoagulantes/administración & dosificación , Enoxaparina/administración & dosificación , Mamoplastia/efectos adversos , Tromboembolia Venosa/prevención & control , Adulto , Anciano , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Quimioprevención/métodos , Estudios de Cohortes , Esquema de Medicación , Enoxaparina/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Subcutáneas , Mamoplastia/métodos , Mastectomía/métodos , Persona de Mediana Edad , Seguridad del Paciente , Cuidados Preoperatorios/métodos , Valores de Referencia , Estudios Retrospectivos , Medición de Riesgo , Resultado del Tratamiento , Tromboembolia Venosa/etiologíaRESUMEN
BACKGROUND: Free flap failure often results from venous thrombosis. The authors developed a rabbit flap model of partial venous obstruction and evaluated four monitoring devices in detecting partial and full venous compromise. METHODS: Nine skin flaps were elevated on their arteriovenous pedicles in rabbits. The flap was assessed with quantitative Doppler of arterial inflow, transcutaneous oxygen and carbon dioxide tension, near-infrared spectroscopy tissue oxygen saturation, and scanning laser Doppler imaging. After a stable baseline was achieved, the outflow vein was subjected to partial and full venous obstruction followed by release. RESULTS: Pedicle arterial flow decreased significantly from baseline (5.9 +/- 3.0 ml/minute) during partial (4.1 +/- 2.4 ml/minute; 30.5 percent; p < 0.01) and full obstruction (0.3 +/- 0.4 ml/minute; 94.9 percent; p < 0.01). All other measures changed significantly with full obstruction: transcutaneous oxygen tension decreased by 79.6 percent; transcutaneous carbon dioxide tension increased by 69.0 percent; near-infrared spectroscopy tissue oxygen saturation decreased by 35.7 percent; and scanning laser Doppler imaging decreased by 78.8 percent. Laser Doppler imaging was the only noninvasive device that decreased significantly (p < 0.01) with partial obstruction, from 222.8 +/- 77.3 units to 186.5 +/- 73.2 units (16.3 percent). CONCLUSIONS: The authors established a venous obstruction flap model and evaluated four clinically relevant monitoring devices during partial and full venous occlusion. All devices detected full occlusion, but only scanning laser Doppler imaging and arterial Doppler detected partial occlusion. Scanning laser Doppler imaging monitoring may allow warning of impending venous obstruction. Near-infrared spectroscopy tissue oxygen saturation varied the least between flaps and therefore may be the most easily interpreted device for full venous occlusion. Both characteristics are important for clinical application.
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Piel/irrigación sanguínea , Colgajos Quirúrgicos/irrigación sanguínea , Animales , Velocidad del Flujo Sanguíneo , Monitoreo de Gas Sanguíneo Transcutáneo , Flujometría por Láser-Doppler , Oxígeno/metabolismo , Conejos , Flujo Sanguíneo Regional , Piel/metabolismo , Espectroscopía Infrarroja Corta , Presión Venosa , Trombosis de la Vena/fisiopatologíaRESUMEN
Involutional entropion, a condition in which the lower eyelid margin is rotated inward, occurs often in elderly people. It can result in corneal and conjunctival irritation by the inverted eyelashes. The pathophysiology has been attributed to multiple factors, including attenuation of the tarsal plate with age, enophthalmus occurring with aging, decreased action of the inferior palpebral muscle, and the overridge of the preseptal orbicularis oculi. Many surgical options have been described for the treatment of involutional entropion. We present an innovative surgical procedure for correction of involutional entropion by a horizontal tangential wedge excision of the tarsal plate.