Large-Volume Fat Grafting: Identifying Risk Factors for Fat Necrosis.

BACKGROUND: Fat necrosis is a well-recognized complication following autologous fat grafting. The purpose of this study was to evaluate the incidence of fat necrosis after large-volume fat grafting and identify risk factors for fat necrosis. METHODS: A retrospective review was performed on 83 consecutive patients who underwent large-volume fat grafting (>100 cc) to the breast performed by the senior author (L.P.B.) between September of 2011 and May of 2016. Fat necrosis was defined as palpable nodules, or nodules seen on imaging. RESULTS: A total of 148 breasts underwent 170 autologous fat transplantations. Indications included the following: 72 reconstructions after surgical therapy and 98 cosmetic augmentations. Mean age was 48 years, median graft volume was 300 cc, and median length of follow-up 423 days. Overall incidence of necrosis was 32.9 percent, with 47.8 percent in previously irradiated patients. Increased incidence of necrosis was associated with increasing fat graft volumes (OR, 1.002; p = 0.032), increasing body mass index (OR, 1.13; p = 0.04), and simultaneous implant exchange with fat ( p = 0.003). Fat grafting volumes greater than 450 cc in a single breast were also associated with an increase in fat necrosis ( p = 0.04). Within a group of six patients who had bilateral fat grafting with unilateral radiation therapy, there was a significant increase in necrosis on the irradiated side ( p = 0.015). In a cohort of non-BRAVA patients, reconstruction (compared to augmentation) was associated with fat necrosis ( p = 0.039). CONCLUSIONS: Increased rates of fat necrosis were associated with volumes greater than 450 cc, patients undergoing concurrent implant exchange with fat grafting, and fat grafting after a history of lumpectomy or mastectomy without preexpansion. In addition, radiation therapy may be associated with a higher rate of complications. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Characteristics of the Superficial Circumflex Iliac Artery Perforator Flap in a Western Population and a Practice Approach for Free Flap Reconstruction.

BACKGROUND: There has been increasing interest in the superficial circumflex iliac artery perforator (SCIP) flap as a source of thin, pliable soft tissue combined with a favorable donor site. Despite several clinical series from Asia, barriers to adoption include reluctance to perform submillimeter "supermicrosurgery" and the effect of body habitus on flap feasibility. The purpose of this study is to distinguish vascular anatomic characteristics of the SCIP flap in a North American population. METHODS: Computed tomography angiography was examined in 84 flaps in healthy prospective renal donor patients from a radiographic database. Descriptive statistics as well as linear regression comparing variables to body mass index (BMI) were performed. RESULTS: Mean BMI was 27.1 ± 3.5 kg/m2, while the mean patient age was 47.8 ± 11.4 years. The superficial circumflex iliac artery (SCIA) originated from the common femoral artery in 92% cases, with remainder originating from the profunda femoris. The mean vessel diameter was 1.85 mm at source vessel origin. Distance from skin to source vessel averaged 30.7 mm. Suprascarpal subcutaneous thickness averaged 16.5 mm. The mean distance from Scarpa's fascia to vessel origin was 14.1 mm. Direct three-dimensional distance from vessel origin to pubic tubercle was 50.2 mm. A medial and lateral perforator split off of the SCIA was observed in 38 cases (45%). Significant differences were shown when comparing BMI to skin to source vessel distance (p < 0.001), suprascarpal subcutaneous fat thickness (p < 0.001), and fascial distance to vessel origin (p < 0.001). BMI did not significantly affect vessel diameter. CONCLUSION: Despite a significantly higher BMI than many previously published cohorts, the SCIP remains an excellent source of thin and pliable tissue. When dissected closer to the source vessel, a vessel caliber of nearly 2 mm can be achieved, which may obviate the need for "supermicrosurgery" in this population.

Skin Excursion with Cannula Lipodissection and the Anatomical Implications of Superficial Musculoaponeurotic System Movement in the Tumescent Face Lift.

BACKGROUND: The tumescent face lift uses the concept of subcutaneous cannula lipodissection of the neck, as opposed to wide skin undermining. Lipodissection mobilizes soft tissue while preserving perforating neurovascular branches. The purpose of this study is two-fold: (1) to compare the skin recruitment with subcutaneous lipodissection of the neck alone versus wide undermining and (2) to examine the effect of superiorly oriented superficial musculoaponeurotic system (SMAS) movement on jowl excursion in the tumescent face lift. METHODS: A cadaveric study was performed on five fresh tissue cadavers. Postauricular skin excursion was measured following subcutaneous lipodissection and then measured again after traditional, wide undermining of the neck skin. Jowl excursion (in reference to the mandibular border) was measured following superiorly oriented SMAS excursion. An electronic force gauge was used to measure force application during measurements. RESULTS: Cannula lipodissection resulted in a mean skin excursion of 41.9 mm. There was no significant difference in skin excursion compared to wide undermining (41.9 mm versus 42.1 mm; p = 0.785). Jowl position, in reference to the mandibular border, moved superiorly by a mean distance of 18.3 mm with vertical SMAS excursion. CONCLUSIONS: Subcutaneous cannula lipodissection results in equivalent skin recruitment in comparison to wide undermining of the neck. A superior vector of pull on the SMAS results in vertical excursion of the jowl in reference to the mandibular border.

Locoregional Cancer Recurrence after Breast Reconstruction: Detection, Management, and Secondary Reconstructive Strategies.

BACKGROUND: Locoregional recurrence of the previously reconstructed breast poses a diagnostic and operative challenge. This study examines detection, management, and reconstructive strategies of locoregional recurrence following postmastectomy breast reconstruction. METHODS: A retrospective review of records was performed on patients treated within the health system for breast cancer from January of 2000 to July of 2014. Of these patients, descriptive factors and operative details were collected for those that developed locoregional recurrence. Subsequent reconstructive operations were also examined. Using a multidisciplinary team, a surveillance/management algorithm was generated. RESULTS: A total of 41 patients with locoregional recurrence were identified (mean time to recurrence, 4.6 years). Two- and 5-year survival following locoregional recurrence was 88 percent and 39 percent, respectively. Locoregional recurrence was found to occur in the following tissue planes: subcutaneous (27 percent), subcutaneous/pectoralis (24 percent), chest wall (37 percent), and axillary (12 percent). The most frequent method of detection was patient concern leading to examination. Older age at the time of locoregional recurrence (p = 0.028), increased time to recurrence/detection (p = 0.024), and chemotherapy before locoregional recurrence (p = 0.014) were associated with the need for a secondary salvage flap. Patients who experienced a subcutaneous recurrence were far less likely to undergo a secondary flap (p = 0.011). Factors associated with loss of the index reconstruction included lower body mass index (p = 0.009), pectoralis invasion (p = 0.05), and implant reconstruction (p = 0.03). CONCLUSIONS: Detection and management of locoregional recurrence requires appropriate physical examination and imaging. Significant factors associated with failure to salvage the initial reconstruction included body mass index, plane of recurrence, and type of initial reconstruction. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Utilizing large volume fat grafting in breast reconstruction after nipple sparing mastectomies.

Nipple sparing mastectomy (NSM) has gained popularity especially in prophylactic mastectomies allowing improved cosmetics. Traditionally reconstruction has utilized implants or autologous tissue. With the development of large volume fat grafting additional reconstructive techniques can be utilized in NSM reconstruction. This can either complement a technique or be a standalone form of reconstruction. This paper is intended to serve as a broad overview of fat grafting and its potential role in reconstructing the breast following nipple sparing mastectomies.

5000 Free Flaps and Counting: A 10-Year Review of a Single Academic Institution's Microsurgical Development and Outcomes.

BACKGROUND: The establishment of an effective clinical and academic culture within an institution is a multifactorial process. This process is cultivated by dynamic elements such as recruitment of an accomplished and diverse faculty, patient geographic outreach, clinical outcomes research, and fundamental support from all levels of an institution. This study reviews the academic evolution of a single academic plastic surgery practice, and summarizes a 10-year experience of microsurgical development, clinical outcomes, and academic productivity. METHODS: A 10-year retrospective institutional review was performed from fiscal years 2006 to 2016. Microsurgical flap type and operative volume were measured across all microsurgery faculty and participating hospitals. Microvascular compromise and flap salvage rates were noted for the six highest volume surgeons. Univariate and multivariable predictors of flap salvage were determined. RESULTS: The 5000th flap was performed in December of 2015 within this institutional study period. Looking at the six highest volume surgeons, free flaps were examined for microvascular compromise, with an institutional mean take-back rate of 1.53 percent and flap loss rate of 0.55 percent across all participating hospitals. Overall, 74.4 percent of cases were breast flaps, and the remaining cases were extremity and head and neck flaps. CONCLUSIONS: Focused faculty and trainee recruitment has resulted in an academically and clinically productive practice. Collaboration among faculty, staff, and residents contributes to continual learning, innovation, and quality patient care. This established framework, constructed based on experience, offers a workable and reproducible model for other academic plastic surgery institutions. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

The State of Prophylactic Mesh Augmentation.

Prophylactic mesh augmentation (PMA) is the implantation of mesh during closure of an index laparotomy to decrease a patient's risk for developing incisional hernia (IH). The current body of evidence lacks refined guidelines for patient selection, mesh placement, and material choice. The purpose of this study is to summarize the literature and identify areas of research needed to foster responsible and appropriate use of PMA as an emerging technique. We conducted a comprehensive review of Scopus, Cochrane, PubMed, and clinicaltrials.gov for articles and trials related to using PMA for IH risk reduction. We further supplemented our review by including select papers on patient-reported outcomes, cost utility, risk modeling, surgical techniques, and available materials highly relevant to PMA. Five-hundred-fifty-one unique articles and 357 trials were reviewed. Multiple studies note a significant decrease in IH incidence with PMA compared with primary suture-only-based closure. No multicenter randomized control trial has been conducted in the United States, and only two such trials are currently active worldwide. Evidence exists supporting the use of PMA, with practical cost utility and models for selecting high-risk patients, but standard PMA guidelines are lacking. Although Europe has progressed with this technique, widespread adoption of PMA requires large-scale pragmatic randomized control trial research, strong evidence-based guidelines, current procedural terminology coding, and resolution of several barriers.

Management of Infected Mesh After Abdominal Hernia Repair: Systematic Review and Single-Institution Experience.

BACKGROUND: Mesh infection after abdominal hernia repair is a devastating complication that affects general and plastic surgeons alike. The purpose of this study was 3-fold: (1) to determine current evidence for treatment of infected abdominal wall mesh via systematic review of literature, (2) to analyze our single-institution experience with treatment of infected mesh patients, and (3) to establish a framework for how to approach this complex clinical problem. METHODS: Literature search was performed using the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines, followed by single-institution retrospective analysis of infected mesh patients. RESULTS: A total of 3565 abstracts and 92 full-text articles were reviewed. For qualitative and quantitative assessment, articles were subdivided on the basis of treatment approach: "conservative management," "excision of mesh with primary closure," "single-stage reconstruction," "immediate staged repair," and "repair in contaminated field." Evidence for each treatment approach is presented. At our institution, most patients (40/43) were treated by excision of infected mesh and single-stage reconstruction with biologic mesh. When the mesh was placed in a retrorectus or underlay fashion, 21.4% rate of hernia recurrence was achieved. Bridged repairs were highly prone to recurrence (88.9%; P = 0.001), but the bridging biologic mesh seemed to maintain domain and potentially contribute to a more effective repair in the future. Of the patients who underwent additional ("secondary") repairs after recurrence, 75% were eventually able to achieve "hernia-free" state. CONCLUSIONS: This study reviews the literature and our single-institution experience regarding treatment of infected abdominal wall mesh. Framework is developed for how to approach this complex clinical problem.

Treating Breast Conservation Therapy Defects with Brava and Fat Grafting: Technique, Outcomes, and Safety Profile.

BACKGROUND: Fat grafting has been demonstrated as a means of reconstructing breast conservation therapy defects. However, there is continued uncertainty regarding its clinical efficacy and oncologic safety. Furthermore, the role of external preexpansion (i.e., with the Brava device) remains unclear in this setting. The purpose of this study was to examine the safety and clinical outcomes of Brava/fat grafting following breast conservation therapy. METHODS: A retrospective chart review was performed on all patients undergoing fat grafting following breast conservation therapy. Complications were defined as either a clinically palpable oil cyst/area of fat necrosis or infection. The mean time of follow-up was 2.3 years. RESULTS: A total of 27 fat grafting sessions were performed on 20 patients, with an overall complication rate of 25 percent. The mean interval from completion of radiation therapy to fat grafting was 7 years and was not a significant predictor for complications (p = 0.46). Among those who underwent repeated grafting, there was no difference in the complication rates between their first and second encounters (p = 0.56). There was no difference in complication rates between patients with Brava preexpansion and those without preexpansion. Patients undergoing Brava preexpansion had a significantly higher initial fill volume in comparison with those who did not (219 cc versus 51 cc; p = 0.0017). There were no cases of locoregional cancer recurrence following fat grafting. CONCLUSION: Brava preexpansion was associated with higher initial fill volume in the setting of breast conservation therapy defects.

Managing Groin Wounds after Infrainguinal Vascular Procedures: Examining the Reoperative Events and Complication Profile of Muscle Flap Reconstruction.

BACKGROUND: The literature has been void of large outcome studies detailing the efficacy and complication profile of muscle flap reconstruction of complex groin wounds. Furthermore, a first-line choice for muscle flap selection remains unclear. The aim of this study is 2-fold: (1) to examine the complication profile and associated risk factors following muscle flap coverage and (2) to provide a compared efficacy analysis of the sartorius muscle flap (SMF) versus the rectus femoris flap (RFF) in the treatment of wounds following an infrainguinal vascular procedure. METHODS: A retrospective review of records was performed on all patients undergoing complex groin wound reconstruction from January 2005 to September 2014. RESULTS: A total of 201 flaps were performed on 184 patients. There were no sentinel bleeding events through the course of graft salvage or perioperative morbidity beyond local wound complications. Coronary artery disease (P = 0.049), dyslipidemia (P < 0.001), diabetes (P = 0.047), and history of multiple prior infrainguinal procedures (P = 0.029) were associated with increased complications following groin wound reconstruction. There was no statistically significant difference in complications in comparing the RFF versus the SMF (27.9% vs. 38.9% respectively; P = 0.109). There was no significant difference in the rates of graft salvage in comparing the RFF versus the SMF (21.6% vs. 16.1%, respectively; P = 0.459). CONCLUSIONS: Muscle flap coverage can be safely employed for vascular graft salvage. Medical comorbidities and multiple prior infrainguinal procedures are predictive of perioperative complications. The SMF and RFF demonstrated equivocal rates of complications and graft salvage. Given that the RFF risks increased functional morbidity and necessitates a second donor site, the SMF may be considered as an effective first-line approach for reconstruction of complex groin wounds.

Concurrent panniculectomy in the obese ventral hernia patient: Assessment of short-term complications, hernia recurrence, and healthcare utilization.

BACKGROUND: Panniculectomy (PAN) is often performed concurrently with ventral hernia repair (VHR) in the obese patient. However, the effectiveness and safety profile of this common practice are not fully established in part because of paucity of comparative effectiveness studies. In this study, a comparative analysis of early complications, long-term hernia recurrence, and healthcare expenditures between VHR-PAN and VHR-only patients is presented. METHODS: From the Healthcare Cost and Utilization Project database, obese patients who underwent VHR with and without concurrent PAN were identified. Multivariate cox proportional-hazards regression modeling was performed to compare outcomes between the two groups. RESULTS: The final cohort included 1013 VHR-PAN and 18,328 VHR-only patients. The VHR-PAN patients experienced a longer adjusted length of hospital stay (6.8 days vs. 5.2 days; p < 0.001), a higher rate of in-hospital adverse events (29.3% vs. 20.7%; AOR = 2.34 [2.01-2.74]), and a higher rate of 30-day readmissions (13.6% vs. 8.1%; AOR = 2.04 [1.69-2.48]). However, the 2-year rate of hernia recurrence was lower in the VHR-PAN group (7.9% vs. 11.3%; AOR = 0.65 [0.51-0.82]). Both groups generated considerable hospital charges ($104,805 VHR-PAN vs. $72,206 VHR-only, p < 0.001). CONCLUSION: Performing a concurrent PAN in the obese hernia patient is associated with a higher rate of early complications and greater healthcare expenditures, but overall a substantially lower incidence of 2-year hernia recurrence. The literature review presented here also highlights a substantial need for further comparative effectiveness studies to create the needed framework for evidence-based guidelines.

A risk model and cost analysis of post-operative incisional hernia following 2,145 open hysterectomies-Defining indications and opportunities for risk reduction.

BACKGROUND: Incisional hernia (IH) is a complication following open abdominal hysterectomy. This study addresses the incidence and health care cost of IH repair after open hysterectomy, and identify perioperative risk factors to create predictive risk models. METHODS: We conduct a retrospective review of patients who underwent open hysterectomy between 2005 and 2013 at the University of Pennsylvania. The primary outcome was post-hysterectomy IH. Univariate/multivariate cox proportional hazard analyses identified perioperative risk factors. We performed cox hazard regression modeling with bootstrapped validation, risk stratification, and assessment of model performance. RESULTS: 2145 patients underwent open hysterectomy during the study period. 76 patients developed IH, and all underwent repair. 31.3% underwent reoperation, generating higher costs ($71,559 vs. $23,313, p < 0.001). 8 risk factors were included in the model, the strongest being presence of a vertical incision (HR = 3.73 [2.01-6.92]). Extreme-risk patients experienced the highest incidence of IH (22%) vs. low-risk patients (0.8%) [C-statistic = 0.82]. CONCLUSIONS: We identify perioperative risk factors for IH and provide a risk prediction instrument to accurately stratify patients in effort to offer risk reductive techniques. SUMMARY: Open hysterectomies account for a magnitude of surgical procedures worldwide. This study presents an internally validated risk model of IH in patients undergoing open hysterectomy after a review of 2145 cases. With an increasing emphasis on prevention in healthcare, we create a risk model to improve outcomes after open hysterectomies in effort to identify high-risk patients, facilitate preoperative risk counseling, and implement evidence-based strategies to improve outcomes.

Attitude of hand surgeons toward Affordable Care Act: A survey of members of American Society for Surgery of the Hand.

The purpose of this study was to examine current attitude of hand surgeons toward the Affordable Care Act (ACA). An electronic survey was sent to members of American Society for Surgery of the Hand (ASSH) to examine their attitude toward the Affordable Care Act. 974 ASSH members responded to the survey (33% response rate). The majority of respondents were male (89%), trained in orthopedic surgery (81%), and in private practice (75%). 41% of respondents rated their knowledge of the ACA as average. Respondents disagreed that the ACA would improve healthcare in the United States (median 2, mean 2.06, scale 1-5), while agreeing that the ACA would decrease reimbursements specific to hand surgery (median 4, mean 4.11).

Predicting incisional hernia after bariatric surgery: a risk stratification model based upon 2161 operations.

BACKGROUND: Incisional hernia (IH) is a persistent cause of morbidity and diminished quality of life and a substantial source of healthcare resource utilization. The literature suggests prophylactic mesh augmentation reduces IH risk in bariatric surgery, but no predictive models are available. OBJECTIVES: Identify factors associated with IH after bariatric surgery to develop a clinically actionable preoperative risk stratification tool to optimize outcomes and mitigate healthcare costs after bariatric surgery. SETTING: University hospital, United States. METHODS: All patients undergoing open or laparoscopic bariatric surgery from January 2005 to June 2013 at one institution were identified. Co-morbidities and operative characteristics were assessed. The primary outcome was surgically treated IH after index procedures. Patients with prior hernia,<1-year follow-up, or body mass index<40 kg/m2 were excluded. Cox hazard regression modeling with bootstrapped validation, risk factor stratification, and assessment of model performance were conducted. RESULTS: A total of 2161 bariatric patients were included, 2.4% of whom developed IH (follow-up 28.3±25.4 mo). Predictors for IH included open surgical approach (hazard ratio [HR] = 10.3), malnutrition (HR = 3.10), prior abdominal surgery (HR = 2.89), and body mass index>60 kg/m2 (HR = 2.60). Based on these risk factors, patients were stratified into low-, moderate-, and high-risk categories for IH development. Of the high-risk patients, 15.2% developed IH compared with .6% of low-risk patients (C-statistic = .85). Treatment of IH and associated complications exceeded $3.5 million in healthcare costs. CONCLUSION: Bariatric surgery conferred an IH risk of 2.4%. IH was associated with additional readmissions and complications and substantially greater costs and resource utilization. This risk stratification tool identifies candidates for prophylactic mesh augmentation, which may optimize outcomes while mitigating costs.

A Risk Model and Cost Analysis of Incisional Hernia After Elective, Abdominal Surgery Based Upon 12,373 Cases: The Case for Targeted Prophylactic Intervention.

OBJECTIVES: Incisional hernia (IH) remains a common, highly morbid, and costly complication. Modest progress has been realized in surgical technique and mesh technology; however, few advances have been achieved toward understanding risk and prevention. In light of the increasing emphasis on prevention in today's health care environment and the billions in costs for surgically treated IH, greater focus on predictive risk models is needed. METHODS: All patients undergoing gastrointestinal or gynecologic procedures from January 1, 2005 to June 1, 2013, within the University of Pennsylvania Health System were identified. Comorbidities and operative characteristics were assessed. The primary outcome was surgically treated IH after index procedures. Patients with prior hernia, less than 1-year follow-up, or emergency surgical procedures were excluded. Cox hazard regression modeling with bootstrapped validation, risk factor stratification, and assessment of model performance were conducted. RESULTS: A total of 12,373 patients with a 3.5% incidence of surgically treated IH (follow-up 32.2 ±â€Š26.6 months) were identified. The cost of surgical treatment of IH and management of associated complications exceeded $17.5 million. Notable independent risk factors for IH were ostomy reversal (HR = 2.76), recent chemotherapy (HR = 2.04), bariatric surgery (HR = 1.78), smoking history (HR = 1.74), liver disease (HR = 1.60), and obesity (HR = 1.96). High-risk patients (20.6%) developed IH compared with 0.5% of low-risk patients (C-statistic = 0.78). CONCLUSIONS: This study demonstrates an internally validated preoperative risk model of surgically treated IH after 12,000 elective, intra-abdominal procedures to provide more individualized risk counseling and to better inform evidence-based algorithms for the role of prophylactic mesh.

Digital image correlation: a novel dynamic three-dimensional imaging technique for precise quantification of the dynamic rhytid and botulinum toxin type a efficacy.

BACKGROUND: Quantification of facial dynamic motion is paramount for improving cosmetic and reconstructive surgical outcomes. The authors introduce digital image correlation using speckle tracking photogrammetry and Aramis software (GOM mbH, Braunschweig, Germany) to study facial dynamics and demonstrate its application in quantifying botulinum toxin efficacy. METHODS: Fourteen subjects were evaluated using a dual camera system and three-dimensional optical analysis. Using Aramis software, the anatomic regions of the glabella, forehead, and total face were identified and highlighted. Tissue strain, defined as either compression or stretch, was measured within these regions over 36 frames during brow furrowing. Each patient was measured before and 2 weeks after injection of 20 units of onabotulinumtoxinA in the glabella. Average stretch and compression in treated areas were analyzed across all available frames. Results were compared using a Wilcoxon signed rank test. RESULTS: After neurotoxin injection, average vertical stretch of the glabella during brow furrowing decreased from 2.51 percent to 1.15 percent (p < 0.05), and average vertical stretch in the forehead decreased from 6.73 percent to 1.67 percent (p < 0.05). Horizontal compression in the glabella decreased from 9.11 percent to 2.60 percent (p < 0.05) and from 4.83 percent to 0.83 percent (p < 0.05) in the forehead. Total facial major strain decreased from 4.41 percent to 3.05 percent (p < 0.05), and total facial minor strain decreased from 5.01 percent to 3.51 percent (p < 0.05). CONCLUSIONS: The authors introduce digital image correlation as a novel technology for measuring dynamic rhytid and neurotoxin efficacy. This technique allows for advancements in the study of dynamic aging and neuromuscular disorders. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, II.

Tamoxifen (selective estrogen-receptor modulators) and aromatase inhibitors as potential perioperative thrombotic risk factors in free flap breast reconstruction.

BACKGROUND: Selective estrogen-receptor modulators and aromatase inhibitors have become ubiquitous in the treatment of breast cancer. However, hormone therapy is a well-established thromboembolic risk factor. The purpose of this study is two-fold: (1) to further evaluate tamoxifen as a potential thrombotic risk factor and (2) to evaluate use of aromatase inhibitors as a potential novel risk factor. METHODS: Abdominally based free flaps were reviewed from January of 2008 to July of 2012. Preoperative records were used to identify patients receiving selective estrogen-receptor modulators (e.g., tamoxifen) or aromatase inhibitors before reconstruction. Patients were instructed to cease tamoxifen 2 weeks before surgery. Patients were not advised to cease their aromatase inhibitor regimen. Univariate statistical analyses included Fisher's exact test and the Mann-Whitney U test. A value of p < 0.05 denoted statistical significance. RESULTS: One thousand three hundred forty-seven flaps were performed on 858 patients. There were no statistically significant differences in thrombotic complications or flap failure in comparing those that did not receive preoperative hormone therapy versus those that did receive preoperative hormone therapy, nor were there significant differences specific to those receiving tamoxifen or aromatase inhibitors. A post hoc power analysis was performed with the supposition that hormone therapy exposure results in a two-fold increase in complication rate. The study power was found to be 0.863. CONCLUSIONS: Tamoxifen may have been previously overestimated as a microvascular thrombotic risk factor. At a minimum, these data suggest that withholding tamoxifen for 2 weeks before surgery can mitigate thrombotic risk.

Intraoperative perfusion management impacts postoperative outcomes: an analysis of 682 autologous breast reconstruction patients.

INTRODUCTION: Anesthetic management remains an understudied aspect of free autologous breast reconstruction. This study aims to critically examine intraoperative anesthetic management as it relates to free flap perfusion and its effect on major complications. METHODS: A retrospective cohort study was performed examining all abdominally based free autologous breast reconstructions from 2005 to 2011 at a single institution. Analysis focused on perioperative care and specifically fluid administration, urine output (UOP), vasopressor administration, and case duration. Outcomes included major intraoperative and postoperative complications. A post-hoc analysis was performed to determine anesthetic factors associated with thrombotic events. RESULTS: Overall, 682 patients (1033 flaps) were included. Patients with low UOP had lower rates of intraoperative fluid infusion rates/kg (p=0.0001), Estimated Blood Loss (EBL) (p=0.006) and pressor administration (p=0.03), but no significant differences were noted in intraoperative thrombotic events according to UOP. However, the below normal UOP cohort demonstrated a significant increased rate of delayed postoperative thromboses (p=0.03). A post hoc analysis of postoperative thrombotic events revealed that low rates of fluid resuscitation (OR=3.01, p=0.04) and low intraoperative UOP (OR=3.67, p=0.04) were independently associated with delayed thrombosis. A sub-analysis demonstrated that patients with ≥2 comorbidities and below normal UOP were at particular risk (any delayed thrombotic event OR=4.3, p=0.03; any delayed venous thrombosis OR=9.1, p=0.03). CONCLUSIONS: This study demonstrates that intraoperative fluid under-resuscitation may place patients at increased risk for postoperative flap thrombosis, and low UOP is an important metric whereby intraoperative resuscitation should be gauged. Patients with comorbid conditions and below normal intraoperative UOP should be monitored particularly closely for delayed thrombotic events. LEVEL OF EVIDENCE: Prognostic/risk category, level II.