Identification of genetic variants of the industrial yeast Komagataella phaffii (Pichia pastoris) that contribute to increased yields of secreted heterologous proteins.

The yeast Komagataella phaffii (formerly called Pichia pastoris) is used widely as a host for secretion of heterologous proteins, but only a few isolates of this species exist and all the commonly used expression systems are derived from a single genetic background, CBS7435 (NRRL Y-11430). We hypothesized that other genetic backgrounds could harbor variants that affect yields of secreted proteins. We crossed CBS7435 with 2 other K. phaffii isolates and mapped quantitative trait loci (QTLs) for secretion of a heterologous protein, ß-glucosidase, by sequencing individual segregant genomes. A major QTL mapped to a frameshift mutation in the mannosyltransferase gene HOC1, which gives CBS7435 a weaker cell wall and higher protein secretion than the other isolates. Inactivation of HOC1 in the other isolates doubled ß-glucosidase secretion. A second QTL mapped to an amino acid substitution in IRA1 that tripled ß-glucosidase secretion in 1-week batch cultures but reduced cell viability, and its effects are specific to this heterologous protein. Our results demonstrate that QTL analysis is a powerful method for dissecting the basis of biotechnological traits in nonconventional yeasts, and a route to improving their industrial performance.

Reducing Chronic Opioid Use: Long-term Impacts of Enhanced Recovery after Mastectomy Protocols.

OBJECTIVE: This study investigates Enhanced Recovery After Surgery (ERAS®) protocols' impact on long-term opioid and sedative use following mastectomy with or without implant-based breast reconstruction (IBBR). SUMMARY BACKGROUND DATA: ERAS® protocols for patients undergoing mastectomy with or without IBBR are associated with decreased length of stay, increased rate of same-day discharge, decreased postoperative pain, and decreased postoperative opioid requirements. However, less is known about their effect on opioid and sedative use beyond 90 days after surgery. METHODS: A retrospective review of all patients undergoing mastectomy with or without IBBR at a single institution between January 2013 and December 2019. Mastectomy ERAS® protocols were implemented in February 2017, creating two groups: pre-ERAS® and ERAS®. Baseline characteristics and prevalence of chronic opioid and sedative use were compared. Univariable and multivariable logistic regression predicted factors associated with increased odds of chronic opioid and sedative use. RESULTS: 756 patients were evaluated: 405 pre-ERAS® and 351 ERAS®. Post-ERAS®, chronic opioid use decreased in opioid-naïve (40% vs. 30%, P=0.024) and opioid-tolerant patients (58% vs. 37%, P=0.002), with no increase in chronic sedative use. There were decreased odds of chronic opioid use for all ERAS® patients (OR=0.57, 95% CI: 0.42-0.76)), and of IBBR patients, those receiving subcutaneous implants (OR=0.31, 95% CI: 0.20-0.48). There was increased chronic opioid-use odds if undergoing bilateral surgery (OR=1.54, 95% CI: 1.14-2.08), two-stage reconstruction (OR=9.78, 95% CI: 5.94-16.09), and for patients with higher PACU pain scores (OR=1.09, 95% CI: 1.03-1.14) or >150 discharge OMEs (OR=2.63, 95% CI: 1.48-4.68). CONCLUSION: ERAS® protocols for mastectomy patients with or without IBR are associated with decreases in chronic opioid use, without concomitant increases in chronic sedative use.

Volumetric Analysis of a Novel Chimeric Gracilis and Profunda Artery Perforator Flap.

BACKGROUND: The presence of a chimeric gracilis and profunda artery perforator (PAP) flap with a common arterial pedicle has been demonstrated on computed tomography angiography in up to 59% of patients and confirmed in a cadaveric model. Already utilized for head and neck reconstruction by Heredero et al, this novel flap could provide more volume than either flap alone which is advantageous, particularly in patients with sizable defects. The purpose of this study was to determine the average tissue volume that can be utilized from this chimeric flap. METHODS: CT Angiogram imaging studies exhibiting chimeric flap anatomy were reviewed over a 7-year period at a single institution utilizing Visage Version 7.1, a radiology picture archiving and communication system. This software was used to trace the flap pedicles and to capture estimated soft tissue volumes of each respective flap. RESULTS: A total of 31 patients, consisting of 52 lower extremity gracilis and PAP chimeric flaps, underwent tissue volume analysis. The average total volume of soft tissue supplied by the gracilis flap was found to be 70.21 cm3 (standard deviation [SD] = 26.99). The average volume of the PAP flap was 31.73 cm3 (SD = 26.12). The average total volume captured by the chimeric gracilis and PAP flap was 101.94 cm3 (SD = 62.40). CONCLUSION: The potential soft tissue volume that can be harvested from a chimeric gracilis and PAP flap is significantly greater than solitary gracilis or PAP flaps. This chimeric flap may serve as a viable and advantageous reconstructive option for patients requiring large volume soft tissue coverage, particularly if other sizable options are not available.

The Impact of Same-Day Discharge and Enhanced Recovery on Patient Quality of Life After Mastectomy with Implant Reconstruction.

BACKGROUND: This study aimed to evaluate how enhanced recovery (ER) protocols and same-day discharge (SDD) influences patients' postoperative quality of life (QOL). METHODS: Patients who underwent mastectomy with implant-based breast reconstruction from 2008 to 2020 were identified in a prospective database. The study assessed QOL with BREAST-Q and Was It Worth It? (WIWI) questionnaires. Responses were compared between the ER and pre-ER groups and between the SDD and hospital stay (HS) groups using one-way analysis of variance (ANOVA) and chi-square tests. RESULTS: The inclusion criteria were met by 568 patients, with a 43% response rate, and 217 patients were included for analysis. Chest physical well-being was lower for the ER cohort, but postoperative breast satisfaction was higher. Psychosocial status, sexual well-being, and satisfaction with information given did not differ significantly between the ER group and the pre-ER or SDD group. In the compared groups, QOL did not differ significantly. CONCLUSIONS: Enhanced recovery with SDD after mastectomy using implant-based reconstruction did not have an adverse impact on patient postoperative QOL.

Postoperative Hematomas in the Era of Outpatient Mastectomy: Is Ketorolac Really to Blame?

BACKGROUND: Enhanced recovery after surgery (ERAS) protocols following mastectomy with or without implant-based breast reconstruction (IBBR) include ketorolac for multimodal perioperative analgesia. There are concerns that ketorolac could be associated with increased risk of postoperative hematoma formation. METHODS: Retrospective review of patients undergoing mastectomy with or without IBBR between January 2013 and December 2019 at a single institution. Patients received 15 mg, 30 mg, or no ketorolac depending on ERAS protocol adherence, patient characteristics, and surgeon preference. Clinically significant hematoma was defined as requiring surgical intervention on day of surgery or postoperative day 1. Patients were compared by demographics, surgical characteristics, ketorolac dose, and hematoma prevalence. Univariable and multivariable logistic regression evaluated hematoma formation odds. RESULTS: Eight hundred patients met inclusion criteria: 477 received ketorolac. Those who received ketorolac were younger, had lower ASA scores, were more likely to have bilateral procedures and undergo concomitant IBBR, had longer operative times, were less likely to take antiplatelet or anticoagulation medications, had higher PACU pain scores, and had higher incidence of hematomas requiring surgical intervention. Of the cohort, 4.4% had clinically significant hematomas. The 15 mg and 30 mg ketorolac groups had similar prevalence (6.0% vs 5.8%, p = 0.95). On univariable regression, there were increased odds of hematoma formation in patients who were younger, had bilateral procedures, had longer OR times, and who received ketorolac. On multivariable regression, none of the prior variables remained significant. CONCLUSION: After accounting for associations with longer operative times, concomitant IBBR, and bilateral procedures, ketorolac administration did not remain an independent risk factor for hematoma formation.

Chest wall resection for breast cancer: 21st century Mayo clinic experience.

BACKGROUND: We hypothesized full-thickness chest wall resection (FTCWR) with advanced surgical techniques and modern systemic therapy is safe, provides local control, and good overall survival. METHODS: Retrospective review of FTCWR (including rib or part of sternum) for breast cancer between 2000 and 2020. Primary endpoints included 90-day morbidities and all-cause mortality. Secondary endpoints were loco-regional and distant recurrence, DFS and overall survival (OS). RESULTS: A total of 35 patients met the criteria. 34 FTCWR were for recurrence and the median time to chest wall recurrence was 6 years. Tumor subtype was triple-negative in 51% and the remainder HR+ Her2-. 58% were palliative resections. FTCWR included rib(s) in 89% and portion of sternum in 57%; 94% required reconstruction and 80% were R0 resections. There were no 90-day mortalities. Overall morbidity was 10/35(28%). 17(49%) patients received neoadjuvant systemic therapy for their recurrence and three received neoadjuvant radiation. Adjuvant treatment included chemotherapy (8), endocrine therapy (3), and both (8). Ten patients (28%) received adjuvant radiation. The Median follow-up was 31 months and there were 6 (17%) loco-regional and 7 (20%) distant recurrences. OS was 86% and 67% at 1 and 3 years, respectively. CONCLUSION: FTCWR was associated with low morbidity, mortality, recurrence rates, and good OS. Selective FTCWR is safe and has acceptable short-term survival rates.

The Effects of Website and Social Media Presence of Integrated Plastic Surgery Residency Programs on Prospective Applicants: An Analysis During the Coronavirus Disease 2019 Pandemic.

PURPOSE: Integrated plastic surgery residency programs have increased their social media presence to educate and recruit prospective residents. This study aims to understand the impact of integrated plastic surgery residency program social media on the 2020 to 2021 applicants' evaluation of prospective programs, particularly during the coronavirus disease 2019 pandemic. MATERIALS AND METHODS: An optional 20-item online survey was sent to integrated plastic surgery residency applicants applying to the authors' program. RESULTS: Surveys were sent to 300 integrated plastic surgery residency applicants with an average of 168 responses (56% response rate). Social media resources included official residency program website (87.1%), Instagram (70.2%), and Doximity (46.8%). The most frequently used resource by applicants was the official residency program website (43.9%); Instagram was the second most frequently used (40.2%) followed by Doximity (8.3%). Most respondents agreed that social media was an effective means to inform applicants (66.1%), and it positively impacted their perception of the program (64.8%). The cited benefits were helping the program exhibit its culture and comradery among residents, faculty, and staff (78.4%). Among applicants, 73.6% noted that it had a significant impact on their perceptions of programs. Most respondents truncated their planned plastic surgery subinternships, completing 1 instead of 3 planned subinternships because of coronavirus disease 2019 limitations. CONCLUSIONS: During the 2020 to 2021 plastic surgery application cycle, applicants used social media accounts of plastic surgery residency programs to inform and educate themselves about prospective programs. This study suggests that investing resources into a social media residency accounts is a meaningful pursuit for integrated plastic surgery programs and is an important aspect in today's recruitment.

Procedural Trends in Medicare Reimbursement and Utilization for Breast Reconstruction: 2000-2019.

PURPOSE: Development of appropriate reimbursement models for breast reconstruction in the United States requires an understanding of relevant economic trends. The purpose of this study is to evaluate longitudinal patterns in Medicare reimbursement for frequently performed breast reconstruction procedures between 2000 and 2019. METHODS: Reimbursement data for 15 commonly performed breast reconstruction procedures were analyzed using the Centers for Medicare & Medicaid Services Physician Fee Schedule Look-Up Tool for each Current Procedural Terminology code. By utilizing changes to the US consumer price index, monetary data were adjusted for inflation to 2019 US dollars. Inflation-adjusted trends were used to calculate average annual and total percentage changes in reimbursement over time. RESULTS: From 2000 to 2019, average adjusted reimbursement for all procedures fell by 13.32%. All procedures demonstrated a negative adjusted reimbursement rate other than immediate insertion of breast prosthesis, which increased by 55.37%. The largest mean decrease was observed in breast reconstruction with other technique (-28.63%), followed by single pedicle transverse rectus abdominis myocutaneous flap (-26.02%), single pedicle transverse rectus abdominis myocutaneous flap with microvascular anastomosis (-23.33%), latissimus dorsi flap (-19.65%), and free flap reconstruction (-19.36%). CONCLUSIONS: There has been a steady yet substantial decline in Medicare reimbursement for the majority of breast reconstruction procedures over the last 20 years. Given increasing medical costs and the financial uncertainty of the US health care system, an understanding of Medicare reimbursement trends is vital for policymakers, administrators, and physicians to develop agreeable reimbursement models that facilitate growth and economic vitality of breast reconstruction in the United States.

Engineering adipic acid metabolism in Pseudomonas putida.

Bio-upcycling of plastics is an upcoming alternative approach for the valorization of diverse polymer waste streams that are too contaminated for traditional recycling technologies. Adipic acid and other medium-chain-length dicarboxylates are key components of many plastics including polyamides, polyesters, and polyurethanes. This study endows Pseudomonas putida KT2440 with efficient metabolism of these dicarboxylates. The dcaAKIJP genes from Acinetobacter baylyi, encoding initial uptake and activation steps for dicarboxylates, were heterologously expressed. Genomic integration of these dca genes proved to be a key factor in efficient and reliable expression. In spite of this, adaptive laboratory evolution was needed to connect these initial steps to the native metabolism of P. putida, thereby enabling growth on adipate as sole carbon source. Genome sequencing of evolved strains revealed a central role of a paa gene cluster, which encodes parts of the phenylacetate metabolic degradation pathway with parallels to adipate metabolism. Fast growth required the additional disruption of the regulator-encoding psrA, which upregulates redundant ß-oxidation genes. This knowledge enabled the rational reverse engineering of a strain that can not only use adipate, but also other medium-chain-length dicarboxylates like suberate and sebacate. The reverse engineered strain grows on adipate with a rate of 0.35 ± 0.01 h-1, reaching a final biomass yield of 0.27 ± 0.00 gCDW gadipate-1. In a nitrogen-limited medium this strain produced polyhydroxyalkanoates from adipate up to 25% of its CDW. This proves its applicability for the upcycling of mixtures of polymers made from fossile resources into biodegradable counterparts.

Unplanned implant removal in locally advanced breast cancer.

Study conducted to determine frequency and timing of unplanned breast implant removal after mastectomy, reconstruction, and postmastectomy radiation (PMRT). From 2010-2017, 52 patients underwent mastectomy, reconstruction, and PMRT. With median follow-up of 3.1 years, 23 patients (44%) experienced implant removal. Implant removal occurred in 9 (17%) patients before starting PMRT and 14 (27%) patients after starting PMRT. Implant removal rates were similar for hypofractionated PMRT compared with standard fractionation and for proton compared with photon PMRT. Implant removal is common for women undergoing mastectomy and reconstruction followed by PMRT. The risk is clinically significant even before starting radiation.

Same-day Discharge Is Safe and Effective After Implant-Based Breast Reconstruction.

BACKGROUND: Same-day discharge after mastectomy is a recently described treatment approach. Limited data exist investigating whether same-day discharge can be successfully implemented in patients undergoing mastectomy with immediate implant-based breast reconstruction (IBR). METHODS: Patients having mastectomy with IBR from 2013 to 2019 were reviewed. Enhanced recovery with same-day discharge was implemented in 2017. Patient characteristics, oncologic treatments, surgical techniques, and 90-day postoperative complications and reoperations were analyzed comparing enhanced recovery patients with historical controls. RESULTS: A total of 363 patients underwent nipple-sparing (214, 59%) or skin-sparing (149, 41%) mastectomy with 1-stage (270, 74%) or tissue expander (93, 26%) IBR. Enhanced recovery was used for 151 patients, with 79 of these patients (52%) discharged same-day. Overall, enhanced recovery patients experienced a significantly lower rate of 90-day complications (21% vs 41%, P < 0.001), including hematoma (3% vs 11%, P = 0.002), mastectomy flap necrosis (7% vs 15%, P = 0.02), seroma (1% vs 9%, P < 0.001), and wound breakdown (3% vs 9%, P = 0.05). Postoperative complication rates did not significantly differ among enhanced recovery patients discharged same day. Postoperative admissions significantly decreased after enhanced recovery implementation (100% to 48%, P < 0.001), and admitted enhanced recovery patients experienced a lower length of stay (1.2 vs 1.8, P < 0.001). Enhanced recovery patients experienced a lower incidence of ≥1 unplanned reoperation (22% vs 33%, P = 0.01); overall average unplanned and total reoperations did not significantly differ between groups. CONCLUSIONS: In conjunction with enhanced recovery practices, same-day discharge after mastectomy with IBR is a safe and feasible treatment approach.

Does Prior Breast Augmentation Affect Outcomes After Mastectomy With Reconstruction? An Analysis of Postoperative Complications and Reoperations.

BACKGROUND: The purpose of this study is to evaluate how prior breast augmentation impacts rates of complications and risk for reoperation after mastectomy with concurrent breast reconstruction. METHODS: Patients undergoing nipple-sparing, skin-sparing, or simple mastectomy with implant-based reconstruction from 2008 to 2018 were identified in a prospective database. Postoperative complications and reoperations were then analyzed comparing patients with prior augmentation to patients without history of previous breast surgery. RESULTS: A total of 468 patients were identified with a median follow-up of 4 years. Of these, 72 had prior augmentation mammoplasty. These patients underwent nipple-sparing (52, 72%), skin-sparing (15, 21%), or simple (5, 7%) mastectomy with immediate direct-to-implant (46, 61%) or tissue expander (26, 35%) reconstruction. On univariate analysis, this cohort had a lower body mass index (23.3 vs 25.3, P = 0.003), a higher rate of nipple-sparing mastectomy (72% vs 54%, P = 0.01), and a higher prevalence of stage I disease (44% vs 33%, P = 0.04). Differences in age, comorbidities, reconstructive techniques, tumor size, and neoadjuvant/adjuvant therapies were not significant. Overall complication rate between patients with or without prior augmentation did not significantly differ (51% vs 50%, P = 0.83); no significant differences in rates of surgical site infection, hematoma, mastectomy skin flap/wound necrosis, nipple complications, implant loss, or capsular contracture were found. Analysis of reoperations between patients with and without prior augmentation revealed no significant differences in average number of subsequent planned, unplanned, or total reoperations. On multivariate analysis, prior breast augmentation was found to be associated with significantly increased risk for undergoing ≥1 unplanned reoperation (odds ratio, 2.28; 95% confidence interval, 1.28-4.05, P = 0.005). CONCLUSIONS: Prior augmentation mammoplasty does not significantly affect rates of postoperative complications after mastectomy with concurrent reconstruction. Although prior augmentation does not affect number of subsequent reoperations on average, it does increase the risk of experiencing 1 or more unplanned reoperation after mastectomy with reconstruction.

3D Nipple-Areolar Tattoo: It's Technique, Outcomes, and Utilization.

BACKGROUND: Three-dimensional (3D) nipple-areolar tattoo is a novel approach to nipple-areolar complex reconstruction for which little data exist. Our aim was to evaluate 3D nipple-areolar tattoo outcomes and investigate if patient factors, payer status, surgeries, or therapies affect tattoo utilization. METHODS: Patients pursuing skin-sparing (SSM) or attempted nipple-sparing mastectomy (NSM) with breast reconstruction from 2008 to 2019 were reviewed. Outcomes included frequency of 3D tattoo, post-procedure complications (infections, or other local adverse sequelae), and rates, indications, and timing of revisions. Patient factors, payer status, surgeries, and adjuvant therapies underwent univariate analysis comparing rates of 3D tattoo and revisions. RESULTS: A total of 191 patients were identified; median follow-up was 4 years. The majority of patients were white (165, 86%), married (146, 76%), and post-menopausal (97, 51%), with private insurance (156, 81%). Surgeries included SSM (172, 90%) or attempted NSM (19, 10%) with implant (154, 81%) or autologous reconstruction (37, 19%). Sixty-two patients (32%) underwent 3D nipple-areolar tattooing. No post-procedure complications occurred. After tattooing, 20 patients (32%) pursued revisions, the majority due to color fading (12, 60%). Average time from tattoo to completion of revisions was 5.6 months. Patients undergoing autologous reconstruction had a higher rate of 3D tattooing (p < 0.001). Adjuvant radiation led to a higher rate of revisions (p = 0.02). Patient factors, payer status, index mastectomy, and chemotherapy did not significantly affect rates of 3D tattooing or revisions. CONCLUSIONS: 3D nipple-areolar tattoo utilization is likely unaffected by age, marriage, menopause, or payer status. Radiotherapy and color fading can lead to more revisions. 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.

Analysis of 20-Year Trends in Medicare Reimbursement for Reconstructive Microsurgery.

BACKGROUND: Microsurgery is being increasingly utilized across surgical specialties, including plastic surgery. Microsurgical techniques require greater time and financial investment compared with traditional methods. This study aimed to evaluate 20-year trends in Medicare reimbursement and utilization for commonly billed reconstructive microsurgery procedures from 2000 to 2019. METHODS: Microsurgical procedures commonly billed by plastic surgeons were identified. Reimbursement data were extracted from The Physician Fee Schedule Look-Up Tool from the Centers for Medicare and Medicaid Services for each current procedural terminology (CPT) code. All monetary data were adjusted for inflation to 2019 U.S. dollars. The average annual and total percentage changes in reimbursement were calculated based on these adjusted trends. To assess utilization trends, CMS physician/supplier procedure summary files were queried for the number of procedures billed by plastic surgeons from 2010 to 2018. RESULTS: After adjusting for inflation, the average reimbursement for all procedures decreased by 26.92% from 2000 to 2019. The greatest mean decrease was observed in CPT 20969 free osteocutaneous flaps with microvascular anastomosis (-36.93%). The smallest mean decrease was observed in repair of blood vessels with vein graft (-9.28%). None of the included procedures saw an increase in reimbursement rate over the study period. From 2000 to 2019, the adjusted reimbursement rate for all procedures decreased by an average of 1.35% annually. Meanwhile, the number of services billed to Medicare by plastic surgeons across the included CPT codes increased by 42.17% from 2010 to 2018. CONCLUSION: This is the first study evaluating 20-year trends in inflation-adjusted Medicare reimbursement and utilization in reconstructive microsurgery. Reimbursement for all included procedures decreased over 20% during the study period, while number of services increased. Increased consideration of these trends will be important for U.S. policymakers, hospitals, and surgeons to assure continued access and reconstructive options for patients.

The Chimeric Gracilis and Profunda Artery Perforator Flap: Characterizing This Novel Flap Configuration with Angiography and a Cadaveric Model.

BACKGROUND: A chimerically configured gracilis and profunda artery perforator (PAP) flap is highly prevalent based on recent computed tomography (CT)-imaging data. The purpose of this study is to further characterize the vascular anatomy of this novel flap configuration and determine the feasibility of flap dissection. METHODS: To characterize flap arterial anatomy, lower extremity CT angiograms performed from 2011 to 2018 were retrospectively reviewed. To characterize venous anatomy and determine the feasibility of flap harvest, the lower extremities of cadavers were evaluated. RESULTS: A total of 974 lower extremity CT angiograms and 32 cadavers were included for the assessment. Of the 974 CT angiograms, majority (966, 99%) were bilateral studies, yielding a total of 1,940 lower extremities (right-lower-extremity = 970 and left-lower-extremity = 970) for radiographic evaluation. On CT angiography, a chimerically configured gracilis and PAP flap was found in 51% of patients (n = 494/974). By laterality, chimeric anatomy was present in 26% of right lower extremities (n = 254/970) and 25% of left lower extremities (n = 240/970); bilateral chimeric anatomy was found in 12% (n = 112/966) of patients. Average length of the common arterial pedicle feeding both gracilis and PAP flap perforasomes was 31.1 ± 16.5 mm (range = 2.0-95.0 mm) with an average diameter of 2.8 ± 0.7 mm (range = 1.3-8.8 mm).A total of 15 cadavers exhibited chimeric anatomy with intact, conjoined arteries and veins allowing for anatomical tracing from the profunda femoris to the distal branches within the tissues of the medial thigh. Dissection and isolation of the common pedicle and distal vessels was feasible with minimal disruption of adjacent tissues. Chimeric flap venous anatomy was favorable, with vena commitante adjacent to the common pedicle in all specimens. CONCLUSION: Dissection of a chimeric medial thigh flap consisting of both gracilis and PAP flap tissues is feasible in a cadaveric model. The vascular anatomy of this potential flap appears suitable for future utilization in a clinical setting.

Same-Day Discharge After Mastectomy: Breast Cancer Surgery in the Era of ERAS®.

BACKGROUND: Enhanced recovery after surgery (ERAS®) principles have been beneficial in major abdominal surgery. ERAS® was instituted in our breast surgery practice in 2017. The goal of this study was to evaluate the feasibility of outpatient mastectomies before and after ERAS®. METHODS: A retrospective review of all mastectomies between 1/2013 and 6/2018 was performed. Patients receiving autologous flap reconstruction were excluded. The institution-specific ERAS® pathway began on February 1, 2017. Patient characteristics, operative intervention, and postoperative outcomes were compared between pre-ERAS® and post-ERAS® groups and between outpatient and inpatient subgroups. Continuous and categorical variables were compared using Wilcoxon rank-sum and Chi-square analyses. RESULTS: A total of 487 patients were analyzed. Three hundred and forty-seven (71%) were prior to ERAS® and 140 after (29%). The two groups were not significantly different in background characteristics. Same-day discharge occurred in 58.6% of post-ERAS® patients versus 7.2% of pre-ERAS® patients (p < 0.001). Liposomal bupivacaine block was used for pain control more in the post-ERAS® group, 62.1% versus 6.1% (p < 0.001). Reconstruction type differed with 45.7% of the post-ERAS® group undergoing direct-to-implant reconstruction versus 34.3% of pre-ERAS® patients (p < 0.001) and with higher rates of submuscular implant and tissue expander placement in the pre-ERAS® versus post-ERAS® group (p < 0.001). Complications rates were lower in the post-ERAS® group versus pre-ERAS® group, 32.9% versus 52.4% (p < 0.001). The outpatient subgroup had higher rates of liposomal bupivacaine administration 74.4% versus 44.8% (p < 0.001). Baseline characteristics and complication rates did not differ between outpatient and admitted subgroups. CONCLUSION: ERAS® principles can be applied to breast cancer patients and allow for outpatient mastectomies with no increase in postoperative morbidity.

Dynamics of Cation-Induced Conformational Changes in Nanometer-Sized Uranyl Peroxide Clusters.

Conformational changes of the pyrophosphate (Pp)-functionalized uranyl peroxide nanocluster [(UO2)24(O2)24(P2O7)12]48- ({U24Pp12}), dissolved as a Li/Na salt, can be induced by the titration of alkali cations into solution. The most symmetric conformer of the molecule has idealized octahedral (Oh) molecular symmetry. One-dimensional 31P NMR experiments provide direct evidence that both K+ and Rb+ ions trigger an Oh-to-D4h conformational change within {U24Pp12}. Variable-temperature 31P NMR experiments conducted on partially titrated {U24Pp12} systems show an effect on the rates; increased activation enthalpy and entropy for the D4h-to-Oh transition is observed in the presence of Rb+ compared to K+. Two-dimensional, exchange spectroscopy 31P NMR revealed that magnetization transfer links chemically unique Pp bridges that are present in the D4h conformation and that this magnetization transfer occurs via a conformational rearrangement mechanism as the bridges interconvert between two symmetries. The interconversion is triggered by the departure and reentry of K (or Rb) cations out of and into the cavity of the cluster. This rearrangement allows Pp bridges to interconvert without the need to break bonds. Cs ions exhibit unique interactions with {U24Pp12} clusters and cause only minor changes in the solution 31P NMR signatures, suggesting that Oh symmetry is conserved. Single-crystal X-ray diffraction measurements reveal that the mixed Li/Na/Cs salt adopts D2h molecular symmetry, implying that while solvated, this cluster is in equilibrium with a more symmetric form. These results highlight the unusually flexible nature of the actinide-based {U24Pp12} and its sensitivity to countercations in solution.

New Perspectives in Surgical Marking Since the Advent of Infrared Laser Angiography.

INTRODUCTION: This study investigates the utility of common surgical dyes under direct visualization and infrared laser angiography. METHODS: Pigments affecting light within the visual (λ = 400-700 nm) and infrared (λ = 700-1000 nm) spectra were placed on subjects spanning the Fitzpatrick scale. Photometric properties of these pigments were assessed under direct visualization and infrared laser angiography. RESULTS: Among patients of various Fitzpatrick classifications, black ink pigment and pigment within the violet spectrum (λ = 380-450 nm) were most distinguishable under direct visualization. Colored inks, gentian violet and methylene blue dyes, were not visualized under infrared laser angiography. Black permanent ink appeared under both direct visualization and infrared laser angiography. Indocyanine green suspended in ethyl alcohol and applied to skin as a marking pen appeared clear under direct visualization and was detectable under infrared laser angiography. CONCLUSIONS: Black permanent marking ink allows visualization of surgical markings under infrared laser angiography, whereas gentian violet and methylene blue did not interfere with infrared visualization. Indocyanine green suspended in ethyl alcohol is a contemporary marking pen that may be used to outline anatomical surface landmarks under infrared laser angiography.

A Newly Described, Highly Prevalent Arterial Pedicle Perfuses Both Gracilis and Profunda Artery Perforator Flap Tissues: An Angiographic Study of the Medial Thigh.

BACKGROUND: Novel secondary flap options are paramount for patients who are not candidates for common reconstructive methods. The purpose of this study is to identify the prevalence of single arterial pedicle supplying both the gracilis muscle and medial thigh tissue carried in a profunda artery perforator (PAP) flap. Such a pedicle could allow the creation of a chimeric gracilis and PAP flap with a single-arterial anastomosis. METHODS: We conducted a retrospective review of 157 lower extremity computed tomography (CT) angiograms to assess the vasculature of the thigh soft tissues. Imaging evaluation was supervised by a board-certified musculoskeletal radiologist. RESULTS: Prevalence of a single-arterial pedicle to a gracilis and PAP flap in each patient was 59% (31% within the right leg and 28% in the left leg). Furthermore, 16% of patients had a common arterial pedicle in both lower extremities. CONCLUSION: Existence of a single-arterial pedicle to both the gracilis muscle and PAP flap tissues is frequently present in most patients in at least one lower extremity. This chimeric flap configuration could serve as a reconstructive avenue for patients, particularly those who have exhausted other more common flap options. Screening angiography is warranted in patients looking for this anatomic variation to establish its presence.

Indocyanine Green Lymphangiography as an Adjunct for the Optimal Identification and Management of Lymphatic Leaks in the Groin.

BACKGROUND: The treatment of lymphatic leaks and lymphoceles in the groin can be challenging with no optimal management determined to date. We postulate that indocyanine green (ICG) lymphangiography improves visualization of the site of a lymphatic leak and can optimize their management. METHODS: A retrospective review was conducted of all cases in which ICG lymphangiography was used in the management of lymphatic leaks in the groin over an 18-month span. The inciting surgical procedure resulting in the leak was determined. Following thorough debridement, ICG was injected intradermally in the distal extremity and the site of the lymphatic leak was documented (superficial or deep) and oversewn. Outcomes were reported with regard to healing, infection, time to drain removal, and adjunctive procedures. RESULTS: Fifteen patients underwent ICG lymphangiography during the surgical treatment of a lymphatic leak in the groin during the study period. In all cases, the site of the lymphatic leak was accurately identified and oversewn. In eight cases, the site of the lymphatic leak was in the subcutaneous tissue superficial to the femoral vessels rather than medial to the femoral vessels in the area of the lymph node basin. A local muscle flap was used in 10 cases simultaneously. All wounds healed primarily without an associated wound or infection. CONCLUSION: ICG lymphangiography facilitated the identification of lymphatic leaks in the groin and optimized their management in these challenging cases, many of which may have been missed if the area around the inguinal lymph node basin was treated exclusively.