Tamoxifen (Selective Estrogen-Receptor Modulators) and Aromatase Inhibitors as Potential Perioperative Thrombotic Risk Factors in Free Flap Breast Reconstruction:

Machine Perfusion Deters Ischemia-Related Derangement of a Rodent Free Flap: Development of a Model

INTRODUCTION

Machine perfusion can enable isolated support of composite tissues, such as free flaps. The goal of perfusion in this setting is to preserve tissues prior to transplantation or provide transient support at the wound bed. This study aimed to establish a rodent model of machine perfusion in a fasciocutaneous-free flap to serve as an affordable testbed and determine the potential of the developed support protocol to deter ischemia-related metabolic derangement.

METHODS

Rat epigastric-free flaps were harvested and transferred to a closed circuit that provides circulatory and respiratory support. Whole rat blood was recirculated for 8 h, while adjusting the flow rate to maintain arterial-like perfusion pressures. Blood samples were collected during support. Extracellular tissue lactate and glucose levels were characterized with a microdialysis probe and compared with warm ischemic, cold ischemic, and anastomosed-free flap controls.

RESULTS

Maintenance of physiologic arterial pressures (85-100 mmHg) resulted in average pump flow rates of 360-430 μL/min. Blood-based measurements showed maintained glucose and oxygen consumption throughout machine perfusion. Average normalized lactate to glucose ratio for the perfused flaps was 5-32-fold lower than that for the warm ischemic flap controls during hours 2-8 (P < 0.05).

CONCLUSIONS

We developed a rat model of ex vivo machine perfusion of a fasciocutaneous-free flap with maintained stable flow and tissue metabolic activity for 8 h. This model can be used to assess critical elements of support in this setting as well as explore other novel therapies and technologies to improve free tissue transfer.

Incidence of Venous Thromboembolism Based on Caprini Score in Deep Inferior Epigastric Perforator Flap Breast Reconstruction

BACKGROUND

 Deep inferior epigastric perforator (DIEP) flaps are commonly used for autologous breast reconstruction, but reported rates of venous thromboembolism (VTE) are up to 6.8%. This study aimed to determine the incidence of VTE based on preoperative Caprini score following DIEP breast reconstruction.

METHODS

 This retrospective study included patients who underwent DIEP flaps for breast reconstruction between January 1, 2016 and December 31, 2020 at a tertiary-level, academic institution. Demographics, operative characteristics, and VTE events were recorded. Receiver operating characteristic analysis was performed to determine the area under the curve (AUC) of the Caprini score for VTE. Univariate and multivariate analyses assessed risk factors associated with VTE.

RESULTS

 This study included 524 patients (mean age 51.2 ± 9.6 years). There were 123 (23.5%) patients with the Caprini score of 0 to 4, 366 (69.8%) with scores 5 to 6, 27 (5.2%) with scores 7 to 8, and 8 (1.5%) patients with scores >8. Postoperative VTE occurred in 11 (2.1%) patients, at a median time of 9 days (range 1-30) after surgery. VTE incidence by the Caprini score was 1.9% for scores 3 to 4, 0.8% for scores 5 to 6, 3.3% for scores 7 to 8, and 13% for scores >8. The Caprini score achieved an AUC of 0.70. A Caprini score >8 was significantly predictive of VTE on multivariable analysis relative to scores 5 to 6 (odds ratio = 43.41, 95% confidence interval = 7.46-252.76, p < 0.001).

CONCLUSION

 In patients undergoing DIEP breast reconstruction, VTE incidence was highest (13%) in Caprini scores greater than eight despite chemoprophylaxis. Future studies are needed to assess the role of extended chemoprophylaxis in patients with high Caprini scores.

Risk of perioperative hormonal breast cancer therapy for microvascular flap complications in breast reconstruction

BACKGROUND

Hormone therapy with selective estrogen modulators (tamoxifen) and aromatase inhibitors is commonly used in the treatment of breast cancer. While the increased risk for thromboembolic events has been known since their early application, the potential risk in microsurgical breast reconstruction is still debated. This study aimed to evaluate the risk for microvascular flap complications in patients with perioperative hormone therapy.

METHODS

All patients who underwent microsurgical breast reconstruction with a deep inferior epigastric perforator (DIEP) or transverse myocutaneous gracilis flap at our institution between March 2010 and November 2020 were retrospectively identified in our records. Patients were grouped according to the type and use of perioperative hormone therapy. Flap-related thromboembolic events, flap loss, and revision procedures were compared and analyzed between groups. Risk factors associated with postoperative microsurgical complications were determined.

RESULTS

A total of 560 patients (656 flaps) were included in our analysis. One hundred ninety-eight patients (224 flaps) received perioperative hormone therapy (35.4%) and 50 (8.9%) postoperative microsurgical events occurred. Tamoxifen and aromatase inhibitors were not associated with postoperative microsurgical events (p = 0.254), full flap loss (p = 0.702), or partial flap loss (p = 0.916). Patients receiving DIEP flaps had a higher risk for postoperative microsurgical complications (OR 2.36, p = 0.004) and partial flap loss (OR 14.66, p < 0.001). A BMI > 30 was associated with an increased risk for partial flap loss (OR 4.2; p < 0.001) CONCLUSION: This article presents one of the largest single-center datasets for the risks of hormone therapy in microsurgical breast reconstruction. Our results show that perioperative hormone therapy does not increase the risk for microsurgical complications. The findings of our study do challenge the common practice of discontinued hormone therapy before microsurgical breast reconstruction.

Preoperative Assessment of the Breast Reconstruction Patient

Through a multidisciplinary approach, as well as, a nuanced appreciation of patient goals and setting appropriate expectations, breast reconstruction can significantly improve the quality of life following mastectomy. A thorough review of the patient medical and surgical history in addition to oncologic treatments will facilitate discussion and recommendations for an individualized shared decision-making reconstructive process. Alloplastic reconstruction, although a highly popular modality, has important limitations. On the contrary, autologous reconstruction is more flexible but requires more thorough consideration.

Perioperative Medication Management in Elective Plastic Surgery Procedures

BACKGROUND

Perioperative medication management is vital to maintain patient safety while under anesthesia, as well as to avoid postoperative complications. Plastic surgeons make daily decisions on whether to ask a patient to stop taking medication before their surgery. These important decisions can affect bleeding risk, wound healing, and interactions with anesthetics, which can range from minor to life-threatening. Current plastic surgery literature lacks a comprehensive review of perioperative medication management, with existing reports focusing on specific procedures and specific medication classes.

METHODS

A PubMed database search was conducted for articles through July 2021. The bibliographies of included studies were also examined for articles not acquired in the initial search queries. The authors included studies on medication usage and perioperative guidance in patients undergoing elective plastic surgery procedures. The authors excluded studies unrelated to plastic surgery and studies where the medications were used as an intervention. Abstracts, animal studies, studies involving the pediatric population, and book chapters were also excluded, as well as articles not published in English.

RESULTS

A total of 801 papers were identified by our search terms. After title and abstract screening, 35 papers were selected for full-text review. After full-text review, 20 papers were selected for inclusion, with an additional 6 papers from cited references added. Of the 26 papers, 6 papers discussed psychotropic drugs, 6 papers discussed medications affecting hemostasis, 4 papers discussed hormone-containing medications, 3 papers discussed antilipid medications, 2 papers discussed antihypertensive medications, 2 papers discussed herbal supplements, 1 paper discussed both psychotropic and herbal supplements, 1 paper discussed medications affecting wound healing, and 1 paper discussed rheumatologic medications. A summary of those recommendations was then compiled together.

CONCLUSIONS

The perioperative medication management in elective plastic surgery procedures remains a complex and multidisciplinary process. It is important to manage these patients in a case-by-case manner and to consult a specialist when necessary. Careful medication reconciliation is essential to decrease the likelihood of adverse outcomes and interactions with perioperative anesthetics.

A UK consensus statement on thromboprophylaxis for autologous breast reconstruction ,

Microsurgical breast reconstruction accounts for 22% of breast reconstructions in the UK. Despite thromboprophylaxis, venous thromboembolism (VTE) occurs in up to 4% of cases. Using a Delphi process, this study established a UK consensus on VTE prophylaxis strategy, for patients undergoing autologous breast reconstruction using free-tissue transfer. It captured geographically divergent views, producing a guide that reflected the peer opinion and current evidence base.

METHODS

Consensus was ascertained using a structured Delphi process. A specialist from each of the UK's 12 regions was invited to the expert panel. Commitment to three to four rounds of questions was sought at enrollment. Surveys were distributed electronically. An initial qualitative free-text survey was distributed to identify likely lines of consensus and dissensus. Each panelist was provided with full-text versions of key papers on the topic. Initial free-text responses were analyzed to develop a set of structured quantitative statements, which were refined via a second survey as a consensus was approached.

RESULTS

The panel comprised 18 specialists: plastic surgeons and thrombosis experts from across the UK. Each specialist completed three rounds of surveys. Together, these plastic surgeons reported having performed more than 570 microsurgical breast reconstructions in the UK in 2019. A consensus was reached on 27 statements, detailing the assessment and delivery of VTE prophylaxis.

CONCLUSION

To our knowledge, this is the first study to collate current practice, expert opinion from across the UK, and a literature review. The output was a practical guide for VTE prophylaxis for microsurgical breast reconstruction in any UK microsurgical breast reconstruction unit.

Impact of anti-oestrogen therapy on lipoprotein(a) in postmenopausal women: a systematic review and meta-analysis of double-blind placebo-controlled clinical studies

PURPOSE

The potential mechanisms of endocrine therapy for thrombosis remain currently unclear, and more studies are warranted for further investigation and elucidation. However, high plasma concentration of lipoprotein(a) (Lp(a)) is a recognized prothrombotic factor. The aim of our study was to systematically evaluate the effect of different anti-oestrogen therapy on plasma Lp(a) level in postmenopausal women.

METHODS

A systematic literature search was conducted in multiple electronic databases to identify the randomized, double-blind, placebo-controlled clinical studies on this topic. Effect size for changes in Lp(a) was expressed as mean difference (MD) and 95% confidence intervals (CI).

RESULTS

Data were pooled from 10 clinical trials comprising 24 treatment arms, which included 2049 women (1128 women in the active-treated arms and 921 women in the control arms). Meta-analysis of data suggested that anti-oestrogen therapy in women significantly reduced Lp(a) [MD = -5.92% (95%CI: -9.05%,-2.8%)].

CONCLUSIONS

This observation is of both clinical and pathophysiological relevance, also in view that the identification of molecular determinants and cellular pathways implicated in Lp(a) synthesis and metabolism is still of concern as a critical issue in lipidology and CV prevention.

The Impact of Obesity on Plastic Surgery Outcomes: A Systematic Review and Meta-analysis

BACKGROUND

Obesity is a potential risk factor for complications in plastic surgeries. However, the data presented by primary studies are contradictory.

OBJECTIVES

The aim of this study was to summarize and clarify the divergences in the literature to provide a better understanding of the impact of obesity in different plastic surgery procedures.

METHODS

We conducted a systematic review and meta-analysis of the impact of obesity on plastic surgery outcomes. Searches were conducted in MEDLINE, LILACS, SciELO, Scopus, Embase, Web of Science, Opengrey.eu, and the Cochrane Database of Systematic Reviews. The primary outcomes assessed were surgical complications, medical complications, and reoperation rates. The secondary outcome assessed was patient satisfaction. Subgroup analysis was performed to investigate the impact of each BMI category on the outcomes.

RESULTS

Ninety-three articles were included in the qualitative synthesis, and 91 were used in the meta-analysis. Obese participants were 1.62 times more likely to present any of the primary outcomes (95% CI, 1.48-1.77; P < 0.00001). The highest increase in risk among plastic surgery types was observed in cosmetic procedures (risk ratio [RR], 1.80; 95% CI, 1.43-2.32; P < 0.00001). Compared with normal-weight participants, overweight participants presented a significantly increased RR for complications (RR, 1.16; 95% CI, 1.07-1.27; P = 0.0004). Most authors found no relation between BMI and overall patient satisfaction.

CONCLUSIONS

Obesity leads to more complications and greater incidence of reoperation compared with nonobese patients undergoing plastic surgeries. However, this effect is not evident in reconstructive surgeries in areas of the body other than the breast.

Safe perioperative tamoxifen use in autologous breast free flap reconstruction: systematic review and meta-analysis

BACKGROUND

Perioperative tamoxifen remains a valuable therapeutic modality for breast cancer patients. Studies in the existing literature have suggested a potential increased risk of thrombotic complications in autologous breast free flap reconstruction patients exposed to tamoxifen perioperatively. However, several recent publications have questioned the validity of these associations. Therefore, we aim to perform a systematic appraisal of the existing literature to determine if perioperative tamoxifen exposure increases the risk of flap complications in autologous breast-free flap reconstruction patients.

METHODS

A systematic literature search was performed using: PubMed, EMBASE, Cochrane Central, Web of Science, EBSCOHost, ClinicalTrials.gov, and TRIP databases from their inception up to April 2021. Articles analyzing the impact of perioperative tamoxifen in autologous breast free flap patients were included. The outcomes assessed were total flap loss, overall flap complications, thrombotic flap complications, which was defined as the sum of arterial and venous flap thrombi, and systemic venous thromboembolism (VTE). Pooled estimates and relative risk were calculated using a random effects model.

RESULTS

9294 Articles were screened and 7 were selected for analysis, which included 3669 flaps in 2759 patients. Compared to patients who did not receive tamoxifen perioperatively, those who received tamoxifen did not have an increased risk of thrombotic flap complications (pooled RR 1.06; 95% CI 0.61-1.84), total flap loss (pooled RR 2.17; 95% CI 0.79-5.95), overall flap complications (pooled RR 1.04; 95% CI 0.76-1.41), or systemic VTE (pooled RR 1.93; 95% CI 0.72-5.13). The heterogeneity of the studies was not significant for any of the outcomes.

CONCLUSIONS

The purpose of this study was to update the current understanding of the impact of perioperative tamoxifen on autologous breast free flap reconstruction outcomes. The existing literature supports that the perioperative continuation of tamoxifen in breast free flap patients is not associated with an increased risk of thrombotic flap complications, total flap loss, overall flap complications, or systemic VTE.

Evaluation of the Number of Follow-up Surgical Procedures and Time Required for Delayed Breast Reconstruction by Clinical Risk Factors, Type of Oncological Therapy, and Reconstruction Approach

BACKGROUND

Breast reconstructive surgery is often a multistage process. The aim was to understand which factors might increase the number of follow-up surgeries and the length of time required to complete the reconstruction process.

METHODS

A cross-sectional analysis was performed. Clinical data of 110 patients who underwent delayed postmastectomy breast reconstruction with a 5-year examination period were reviewed retrospectively. Impact of clinical risk factors, oncological therapy, and reconstruction approach on the number of surgeries and the length of required time was analyzed. Mann-Whitney U test and Kruskal-Wallis rank sum test were used.

RESULTS

In patients undergoing perioperative hormone therapy, an average of 2.9 surgeries and length of 20.2 months were required compared to 2.3 surgeries and 14.0 months in patients without hormone therapy (P = 0.003; P = 0.005). Previous abdominal surgery was associated with an increased number of breast reconstruction stages of 3.1 per patient (P = 0.056) and a longer reconstruction time of 23.0 months (P = 0.050). Patients undergoing nipple reconstruction or implant revision required an increased number of surgeries (P < 0.001; P = 0.012) and a longer reconstruction time (P = 0.002; P < 0.001). Contralateral breast surgery and flap revision were associated only with an increased number of surgeries (P < 0.001; P < 0.001).

CONCLUSION

Perioperative hormone therapy was associated with a significantly higher number of surgeries and duration of time required to complete the reconstruction process. The highest increase in the number of surgeries was in patients with flap revision including anastomosis revision and necrectomy.

LEVEL OF EVIDENCE IV

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 .

A Review of Venous Thromboembolism Risk Assessment and Prophylaxis in Plastic Surgery

BACKGROUND

Venous thromboembolism is a significant cause of postoperative death and morbidity. While prophylactic and treatment regimens exist, they usually come with some risk of clinically relevant bleeding and, thus, must be considered carefully for each individual patient.

METHODS

This special topic article represents a review of current evidence regarding venous thromboembolism risk, biology, and prevention in plastic surgery patients. The specific types and duration of available prophylaxis are also reviewed. The balance of venous thromboembolism risk must be weighed against the risk of hemorrhage.

RESULTS

Though alternatives exist, the most validated risk assessment tool is the 2005 modification of the Caprini Risk Assessment Model. Controversies remain regarding recommendations for outpatient and low risk cosmetic patients. The authors additionally make recommendations for high-risk patients regarding the use of tranexamic acid, estrogen therapy, anesthesia, and prophylaxis regimens.

CONCLUSION

Our profession has made great strides in understanding the science behind venous thromboembolism, risk stratification for patients, and prophylactic regimens; yet, continued studies and definitive data are needed.

Latest Advancements in Autologous Breast Reconstruction

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand the available donor sites for autologous breast reconstruction. 2. Describe the advantages and limitations of each donor site. 3. Provide a rational, algorithmic preoperative evaluation and approach for patients seeking autologous breast reconstruction. 4. Develop an effective postoperative monitoring system to minimize complications and maximize salvage of microvascular thromboses.

SUMMARY

Breast reconstruction remains at the heart of the field of plastic and reconstructive surgery, and it is continuously evolving. Tremendous advances in breast implant technology and supplemental products, particularly acellular dermal matrices, have revolutionized breast reconstruction in the modern era. However, microvascular free flap breast reconstruction has also witnessed profound advancements with exceptionally high success rates, with the ability to provide the most durable and natural breast reconstruction. Although the pendulum oscillates between prosthesis-based reconstruction and autologous tissue, the present synopsis will focus on autologous free flap breast reconstruction from an historical perspective, recent advancements in microsurgery, and the future of autologous breast reconstruction.

Effect of Cross-Sex Hormone Therapy on Venous Thromboembolism Risk in Male-to-Female Gender-Affirming Surgery

Individuals with gender dysphoria often seek medical interventions, such as hormone treatment and surgery, to live as their identified gender. Cross-sex hormone therapy typically consists of various estrogen formulations which confer varying risks of venous thromboembolism (VTE). Currently, there is no standard practice by surgeons regarding the preoperative gender-affirming surgery (GAS) hormone regimen of male-to-female (MTF) patients to minimize thromboembolic postoperative complications. The aim of this review is to examine the current literature on VTE occurring in MTF transgender patients on cross-sex hormone therapy (CSHT) when undergoing various gender-affirming surgeries-facial feminization surgery (FFS), top surgery (TS), and bottom surgery (BS)-to understand how evidence-based recommendations regarding perioperative hormone regimens can be established to improve clinical outcomes. Within the past 25 years, 7 published studies have examined the incidence of VTE in MTF patients undergoing GAS procedures. Two of these articles examined MTF patients undergoing FFS, 1 article reported a patient who had undergone BS and FFS during the same hospitalization, and the remaining 4 articles investigated VTE risk in BS. Our review supports that plastic surgeons who perform GAS are divided on their preferred CSHT protocols, with some requiring patients to suspend their CSHT weeks before surgery and others allowing patients to continue CSHT through the day of surgery. Three of the 7 studies detailed a CSHT perioperative regimen which instructed patients to suspend CSHT sometime before surgery; 1 study tapered CSHT to lower levels before surgery; the remaining 3 studies did not specify a CSHT perioperative regimen. This review highlights the paucity of data failing to support that continuing CSHT through GAS elevates VTE risk. We conclude that in the absence of definitive VTE risk factors (e.g., smoking, clotting disorders, or malignancy), surgeons may engage MTF patients in joint decision-making process to determine the most optimal perioperative CSHT management plan on a case-by-case basis. Future studies are warranted to evaluate VTE risk based on patient age, type of surgery, operating time, prophylactic measures, follow-up time, and CSHT perioperative regimens.

Microvascular breast reconstruction and thromboembolic events in patients on hormone therapy: Audit of practice from a tertiary referral centre

INTRODUCTION

Hormonal therapy with tamoxifen and aromatase inhibitors reduces breast cancer recurrence and mortality but represents a risk factor for thromboembolic events. Therefore, most surgeons discontinue hormonal agents before microvascular surgery and for a variable period thereafter. There are no guidelines regarding when therapy should be stopped (preoperatively) or when it should be resumed (post-operatively). We, therefore, audited our hospital practice with the objective of making recommendations for microvascular breast reconstruction patients.

PATIENTS AND METHODS

A review was performed of all free flap breast reconstructions between 2014 and 2019. Patients were classified according to hormone medication status at operation. Timings of drug cessation and recommencement were recorded. Thrombotic events, namely flap microvascular thrombosis, deep vein thrombosis, superficial vein thrombosis and pulmonary embolism, were compared.

RESULTS

A total of 240 patients had 275 free flaps over five years with 36 receiving hormone therapy within one month prior to surgery, which was discontinued 8.5 days (range: 0-28 days) before surgery. Intraoperative microvascular thromboses (HT 2.0%, NHT 0%, and p = 0.869) and post-operative microvascular complications/flap re-explorations (HT 6.6%, NHT 0%, and p = 0.234) were comparable between the two groups. Systemic venous thromboembolic events were also similar (HT 8.3%, NHT 6.1%, and p = 0.893). Age, BMI, smoking status and preoperative chemotherapy did not influence the incidence of thrombotic complications.

CONCLUSION

Hormone therapy did not significantly increase the risk of thromboembolic events. Despite the widespread practice of withholding it for 2 weeks prior to reconstructive surgery, this study does not support such practice being beneficial in terms of thromboembolic events and flap viability. Large-scale trials are needed to establish definitive protocols.

[Surgical revision in case of DIEP failure in breast reconstruction]

INTRODUCTION

Immediate or delayed breast reconstruction by deep inferior epigastric perforant flap (DIEP) is a frequent and widespread autologous breast reconstruction technique that presents a risk of failure inherent in its microsurgical nature. The main objective was to evaluate the interest of surgical revision in case of DIEP failure, the secondary objective was to evaluate the consequences of surgical revision on the subsequent management.

MATERIALS AND METHODS

This is a retrospective monocentric and single-operator analytical study of 167 unilateral DIEPs carried out from 2008 to 2016. Two groups were compared: success of DIEP without revision versus DIEP requiring a revision that resulted in success or failure. After analyzing the failure and recovery rates of DIEP, we compared the transfusion rate, total operating time, hospitalization time, and final breast reconstruction in the two groups.

RESULTS

One hundred and sixty-seven DIEPs were performed from 2008 to 2016 in 167 women, 18 revisions were reported (10.7%), 12 revisions were successfully reported (7.2%) 6 failures were reported after revision (3.6%). Surgical revision allows the flap to be rescued in 67% of cases. Revision increases the risk of blood transfusion by a factor of 12 (OR=12.24 [95% CI=3.74-43.17] P<0.05). Revision or failure doubles the total operating time (281.8min [170-570] vs. 577.8min [285-860] P<0.05) and increases hospitalization time by 2.5days compared to DIEP's initial success (5.74days [4-9] vs. 8.33days [5-17] P<0.05). Fifty percent of patients choose another type of breast reconstruction after DIEP failure.

CONCLUSION

DIEP is a reliable microsurgical breast reconstruction technique, failure can be prevented in two thirds of cases by monitoring and early reoperation.

Impact of hormonal therapy and other adjuvant therapies on contralateral breast volume change after implant-based breast reconstruction

BACKGROUND

Adjuvant therapy after breast surgery, including tamoxifen or aromatase inhibitors, improves the postoperative outcomes and long-term survival of breast cancer patients. The aim of this study was to determine whether volume changes occurred in the contralateral breast during hormonal or other adjuvant therapies.

METHODS

This study reviewed 90 patients who underwent unilateral breast reconstruction between September 2012 and April 2018 using tissue expanders and a permanent implant after the surgical removal of breast cancer. The volume of the contralateral breast was measured using a cast before the first (tissue expander insertion) and second (permanent implant change) stages of surgery. Changes in breast volume were evaluated to determine whether adjuvant therapy such as hormonal therapy, chemotherapy, and radiation therapy influenced the volume of the contralateral breast.

RESULTS

The group receiving tamoxifen therapy demonstrated a significant decrease in volume compared with the group without tamoxifen (-7.8% vs. 1.0%; P=0.028). The aromatase inhibitor-treated group showed a significant increase in volume compared with those who did not receive therapy (-6.2% vs. 4.5%; P=0.023). There were no significant differences between groups treated with other hormonal therapy, chemotherapy, or radiation therapy.

CONCLUSIONS

Patients who received tamoxifen therapy showed a significant decrease in volume in the contralateral breast, while no significant change in weight or body mass index was found. Our findings suggest that we should choose smaller implants for premenopausal patients, who have a high likelihood of receiving tamoxifen therapy.

Does Hormone Therapy Use Increase Perioperative Complications in Abdominally Based Microsurgical Breast Reconstruction?

BACKGROUND

The use of hormone therapy (tamoxifen and aromatase inhibitors) has been shown to increase venous thromboembolism. As breast cancer patients undergoing microsurgical breast reconstruction are often receiving hormone therapy, it is unclear whether this increased thrombotic risk is associated with increased flap loss.

METHODS

A retrospective review was performed on patients undergoing abdominally based microsurgical breast reconstruction at an academic institution from 2004 to 2015. Patients were divided by use of hormone therapy at the time of surgery. Complication rates, including complete or partial flap loss and overall complications, were compared and analyzed using univariate and logistic regression models.

RESULTS

Among a total of 853 patients (1253 flaps), 193 patients (269 flaps) were receiving hormone therapy and 660 patients (984 flaps) were not. Patients on hormone therapy had higher rates of previous breast surgery, advanced cancer stage, chemoradiation before reconstruction, and delayed and unilateral reconstruction. There were no statistically significant differences between hormone therapy patients and nontherapy patients in complete flap loss (1.0 percent versus 1.1 percent) and partial flap loss (2.2 percent versus 1.5 percent). Hypertension and previous breast surgery were the only independent risk factors for minor complications (adjusted OR, 2.1; 95 percent CI, 1.3 to 3.6; p = 0.005; and adjusted OR, 1.8; 95 percent CI, 1.2 to 2.7; p = 0.009, respectively) and overall complications (adjusted OR, 2.2; 95 percent CI, 1.3 to 3.7; p = 0.004; and adjusted OR, 1.9; 95 percent CI, 1.3 to 3.0; p = 0.003, respectively).

CONCLUSIONS

Hormone therapy was not associated with a higher incidence of complete or partial flap loss or overall complications. The authors propose an individualized approach to the preoperative cessation of tamoxifen or aromatase inhibitors.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Clinically Significant Thromboembolic Disease in Adult Spinal Deformity Surgery: Incidence and Risk Factors in 737 Patients

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Describe the rate and risk factors for venous thromboembolic events (VTEs; defined as deep venous thrombosis [DVT] and/or pulmonary embolism [PE]) in adult spinal deformity (ASD) surgery.

METHODS

ASD patients with VTE were identified in a prospective, multicenter database. Complications, revision, and mortality rate were examined. Patient demographics, operative details, and radiographic and clinical outcomes were compared with a non-VTE group. Multivariate binary regression model was used to identify predictors of VTE.

RESULTS

A total of 737 patients were identified, 32 (4.3%) had VTE (DVT = 14; PE = 18). At baseline, VTE patients were less likely to be employed in jobs requiring physical labor (59.4% vs 79.7%, P < .01) and more likely to have osteoporosis (29% vs 15.1%, P = .037) and liver disease (6.5% vs 1.4%, P = .027). Patients with VTE had a larger preoperative sagittal vertical axis (SVA; 93 mm vs 55 mm, P < .01) and underwent larger SVA corrections. VTE was associated with a combined anterior/posterior approach (45% vs 25%, P = .028). VTE patients had a longer hospital stay (10 vs 7 days, P < .05) and higher mortality rate (6.3% vs 0.7%, P < .01). Multivariate analysis demonstrated osteoporosis, lack of physical labor, and increased SVA correction were independent predictors of VTE (r² = .11, area under the curve = 0.74, P < .05).

CONCLUSIONS

The incidence of VTE in ASD is 4.3% with a DVT rate of 1.9% and PE rate of 2.4%. Osteoporosis, lack of physical labor, and increased SVA correction were independent predictors of VTE. Patients with VTE had a higher mortality rate compared with non-VTE patients.

Towards standardization of training and practice of reconstructive microsurgery: an evidence-based recommendation for anastomosis thrombosis prophylaxis

BACKGROUND

Despite significant improvements in survival rates, free flap failures still occur even in experienced hands and are most commonly due to arterial or venous thrombosis. In the absence of an evidence-based guideline on the prevention of thrombosis, we reviewed the literature to assess the evidence base for commonly used interventions aimed at its prevention.

METHODS

A comprehensive literature search was performed using the following keywords "free flap" and microsurgery with "pre-operative screening," "prevention of thrombosis," "ketorolac," "heparin," "low molecular weight heparin," "aspirin," "dextran," and "statins."

RESULTS

Thirteen clinical studies were included in this review. No high-level evidence is available to support any perioperative or postoperative interventions aimed at reducing the risk of flap thrombosis.

CONCLUSIONS

Higher level studies are needed to investigate the clinical use of antithrombotic medications in microsurgery; however, given the small failure rates in modern practice, these will need to be large multicenter trials in order to reach sufficient power.Level of Evidence: Level III, risk/prognostic study.

Complications and thromboembolic events associated with tamoxifen therapy in patients with breast cancer undergoing microvascular breast reconstruction: a systematic review and meta-analysis

PURPOSE

Tamoxifen therapy is integral in the treatment of patients with hormone receptor-positive breast cancer. However, there is an association between tamoxifen and thromboembolic events. Flap and systemic thromboembolic events have devastating consequences in microvascular breast reconstruction. Currently, there are conflicting data on the association between tamoxifen therapy and thromboembolic complications for patients undergoing microvascular breast reconstruction. The objective of this study is to determine if perioperative tamoxifen therapy modifies the risk of complications and thromboembolic events for patients with breast cancer undergoing microvascular breast reconstruction.

METHODS

A comprehensive literature search was performed across six databases from January 2003 to February 2016. Pooled estimates and relative risk (RR) were calculated using a random-effects model, confounding was examined with meta-regression, and risk of bias was evaluated. Primary outcomes were thrombotic flap complications and total flap loss. Study quality was assessed using Downs and Black criteria.

RESULTS

Of 95 studies reviewed, 4 studies comprising 1700 patients and 2245 procedures were included for analysis. Compared to non-recipients, patients on tamoxifen were at increased risk of developing thrombotic flap complications (pooled RR 1.5; 95% CI 1.14-1.98) and total flap loss (pooled RR 3.35; 95% CI 0.95-11.91). There was no significant heterogeneity present in either outcome and no evidence of publication bias.

CONCLUSIONS

Perioperative tamoxifen therapy may increase the risk of thrombotic flap complications and flap loss for patients with breast cancer undergoing microvascular reconstruction. These findings further the ability of providers to make evidence-based recommendations in the perioperative management of patients with breast cancer.