A multicentre clinical trial evaluating the outcomes of two application regimens of a unique keratin-based graft in the treatment of Wagner grade one non-healing diabetic foot ulcers.

Diabetic foot complications that lead to lower extremity amputations pose a significant challenge to the entire global health system. In this multicentre clinical trial, 26 patients with chronic Wagner one diabetic foot ulcers (DFUs) were treated with a unique human keratin matrix graft applied either weekly or bi-weekly, in addition to standard of care. The hypothesis was that bi-weekly application would be similar to weekly application. The primary endpoint was complete wound closure by 12 weeks, and secondary endpoints included healing time, percent area reduction and weekly changes in peripheral neuropathy, pain and quality of life. In the intent-to-treat population, 77% (10/13) of DFUs treated with bi-weekly application healed compared with 69% (9/13) treated with weekly application. The mean time to heal within 12 weeks in the bi-weekly group was 61 days and in the weekly group was 54 days. The mean percent area reduction at 12 weeks was 94.7% in the bi-weekly group compared with 84.8% in the weekly group. The number of grafts used in the bi-weekly group was 3.9 compared with 6.2 in the weekly group. The results of this trial confirm our hypothesis that whether bi-weekly or weekly application of the unique keratin matrix graft is used to treat nonhealing indolent DFUs, there is a high rate of complete healing. Based on these results, future studies should be conducted that further investigate the use of this novel human keratin matrix graft for the treatment of chronic DFUs.

A novel surgical risk predictor combining frailty and hypoalbuminemia - A cohort study of 9.8m patients from the ACS-NSQIP database.

INTRODUCTION: The functional decline seen in frail patients is associated with significant morbidity and mortality. The modified frailty index 5 (mFI-5) score is an accepted risk predictor score in surgery. Hypoalbuminemia has been correlated with poor postoperative outcomes.There exists, however, a gap in the literature regarding the combined assessment of frailty and hypoalbuminemia and the predictive power of this combined assessment. This retrospective cohort study aimed to investigate the association of preoperative albumin and frailty, as assessed with the mFI-5 score, and its ability to predict surgical outcomes. METHODS: We queried the ACS-NSQIP database (2008-2021) to identify all surgical patients. Perioperative data, including demographics and preoperative laboratory values, including albumin, were collected. The predictive power of the mFI-5 and hypoalbuminemia (Alb) independently, and in combination (mFI-5+Alb), was assessed using multivariable linear and logistic regression models 30-day outcomes were assessed including mortality, length of hospital stay, reoperation, medical and surgical complications, and discharge destination. RESULTS: A total of 9,782,973 patients were identified of whom 4,927,520 (50.4%) were non-frail (mFI=0), 3,266,636 had a frailty score of 1 (33.4%), 1,373,968 a score of 2 (14.0%), 188,821 a score of 3 (1.9%) and 26,006 a score greater or equal to 4 (0.3%). Albumin levels were available for 4,570,473 patients (46.7%), of whom 848,315 (18.6%) had hypoalbuminemia. The combined assessment (mFI-5+Alb) was found to be a more accurate risk predictor than each factor independently for all outcomes. A weak negative correlation between serum albumin levels and mFI scores was established (Spearman R: -0.2; <0.0001). CONCLUSIONS: Combined assessment of frailty and albumin was the strongest risk predictor. Therefore, for patients undergoing surgery, we recommend consideration of both serum albumin and frailty in order to optimally determine perioperative planning, including multi-disciplinary care mobilization and pre- and posthabilitation.

Breast organoid suspension cultures maintain long-term estrogen receptor expression and responsiveness.

Organoid cultures offer a powerful technology to investigate many different aspects of development, physiology, and pathology of diverse tissues. Unlike standard tissue culture of primary breast epithelial cells, breast organoids preserve the epithelial lineages and architecture of the normal tissue. However, existing organoid culture methods are tedious, difficult to scale, and do not robustly retain estrogen receptor (ER) expression and responsiveness in long-term culture. Here, we describe a modified culture method to generate and maintain organoids as suspension cultures in reconstituted basement membrane (™Matrigel). This method improves organoid growth and uniformity compared to the conventional Matrigel dome embedding method, while maintaining the fidelity of the three major epithelial lineages. Using this adopted method, we are able to culture and passage purified hormone sensing (HS) cells that retain ER responsiveness upon estrogen stimulation in long-term culture. This culture system presents a valuable platform to study the events involved in initiation and evolution of ER-positive breast cancer.

A nomogram for predicting outcomes following pedicled flap reconstruction of the lower extremity.

INTRODUCTION: Lower extremity reconstructions with soft tissue flaps account for a significant proportion of reconstructive surgery. Pedicled flaps are a procedure of choice, particularly in multimorbid patients and those with small to medium-sized defects. Complication rates are high and should not be underestimated, with accurate preoperative risk factor assessment being imperative. METHODS: Using the American College of Surgeons National Surgical Quality Improvement Program Database (2008-2021), we analyzed all patients who underwent pedicled flap reconstruction of the lower extremity. Demographic data, comorbidities, and perioperative data were extracted. We identified risk factors of major surgical complications within 30 days of surgery through uni- and multivariate regression analyses. On this basis, a nomogram for predicting the risk of complications was developed to allow for feasible point-of-care risk assessment. RESULTS: A total of 6475 adult patients were identified. The most common comorbidities were hypertension (n = 3363, 51.9%) and obesity (n = 2306, 35.6%) and most common American Society of Anesthesiologists (ASA) class was class 3 (n = 3703, 57.2%). The most common complication was bleeding/transfusion (n = 1293, 19.9%). Multivariate regression revealed longer procedures, inpatient setting, higher ASA scores, hypertension, and procedures performed by orthopedic and vascular surgeons as predictors for higher risk of post-operative complications. CONCLUSION: Leveraging a risk- and case-mix-adjusted multi-institutional database, a nomogram for post-operative surgical complications within 30 days after pedicled flap reconstruction in the lower extremity was developed. This broadly applicable risk prediction tool can aid in decision-making when assessing patient eligibility.

Standardized Protocols for Clinical and Histopathological Characterization of Hidradenitis Suppurativa Tissue Specimens.

Methods for describing and reporting the clinical and histologic characteristics of cutaneous tissue samples from patients with hidradenitis suppurativa (HS) are not currently standardized, limiting clinicians' and scientists' ability to uniformly record, report, and communicate about the characteristics of tissue used in translational experiments. A recently published consensus statement outlined morphological definitions of typical HS lesions, but no consensus has been reached regarding clinical characterization and examination of HS tissue samples. In this study, we aimed to establish a protocol for reporting histopathologic and clinical characteristics of HS tissue specimens. This study was conducted from May 2023 to August 2023. Experts in clinical care, dermatopathology, and translational research were recruited, and a modified Delphi technique was used to develop a protocol for histologic reporting and clinical characterization of submitted tissue specimens from patients with HS. A total of 27 experts participated (14 dermatologists, 3 fellowship-trained dermatopathologists, 3 plastic surgeons, 3 general surgeons, and 4 research scientists) in creating and reviewing protocols for the clinical and histopathological examination of HS tissue specimens. The protocols were formatted as a synoptic report and will help to consistently classify specimens in biobanks on the basis of histologic features and more accurately report and select samples used in translational research projects.

Current and future applications of artificial intelligence in surgery: implications for clinical practice and research.

Surgeons are skilled at making complex decisions over invasive procedures that can save lives and alleviate pain and avoid complications in patients. The knowledge to make these decisions is accumulated over years of schooling and practice. Their experience is in turn shared with others, also via peer-reviewed articles, which get published in larger and larger amounts every year. In this work, we review the literature related to the use of Artificial Intelligence (AI) in surgery. We focus on what is currently available and what is likely to come in the near future in both clinical care and research. We show that AI has the potential to be a key tool to elevate the effectiveness of training and decision-making in surgery and the discovery of relevant and valid scientific knowledge in the surgical domain. We also address concerns about AI technology, including the inability for users to interpret algorithms as well as incorrect predictions. A better understanding of AI will allow surgeons to use new tools wisely for the benefit of their patients.

A purified reconstituted bilayer matrix shows improved outcomes in treatment of non-healing diabetic foot ulcers when compared to the standard of care: Final results and analysis of a prospective, randomized, controlled, multi-centre clinical trial.

As the incidence of diabetic foot ulcers (DFU) increases, better treatments that improve healing should reduce complications of these ulcers including infections and amputations. We conducted a randomized controlled trial comparing outcomes between a novel purified reconstituted bilayer membrane (PRBM) to the standard of care (SOC) in the treatment of non-healing DFUs. This study included 105 patients who were randomized to either of two treatment groups (n = 54 PRBM; n = 51 SOC) in the intent to treat (ITT) group and 80 who completed the study per protocol (PP) (n = 47 PRBM; n = 33 SOC). The primary endpoint was the percentage of wounds closed after 12 weeks. Secondary outcomes included percent area reduction, time to healing, quality of life, and cost to closure. The DFUs that had been treated with PRBM healed at a higher rate than those treated with SOC (ITT: 83% vs. 45%, p = 0.00004, PP: 92% vs. 67%, p = 0.005). Wounds treated with PRBM also healed significantly faster than those treated with SOC with a mean of 42 versus 62 days for SOC (p = 0.00074) and achieved a mean wound area reduction within 12 weeks of 94% versus 51% for SOC (p = 0.0023). There were no adverse events or serious adverse events that were related to either the PRBM or the SOC. In comparison to the SOC, DFUs healed faster when treated with PRBM. Thus, the use of this PRBM is an effective option for the treatment of chronic DFUs.

Outcomes of Dermal Regeneration Templates in Irradiated and Nonirradiated Scalp Defects.

OBJECTIVES: Dermal regeneration templates (DRTs) are frequently used to treat scalp defects. The aim was to compare the time course of healing for DRTs in scalp defects with and without preoperative radiation. METHODS: The authors conducted a retrospective cohort study of DRT-based scalp reconstruction at 2 academic medical centers between 2013 and 2022. Information was collected on demographic variables, comorbidities, medication use, history of radiation, and DRT outcomes. The primary outcome was DRT loss, defined as exposed calvarium or DRT detachment based on postoperative follow-up documentation. Kaplan-Meier survival analysis and multivariable Cox proportional-hazard regressions were used to compare DRT loss in irradiated and nonirradiated defects. Multivariable logistic regressions were used to compare 30-day postoperative complications (infection, hematoma, or seroma) in irradiated and nonirradiated defects. RESULTS: In total, 158 cases were included. Twenty-eight (18%) patients had a preoperative history of radiation to the scalp. The mean follow-up time after DRT placement was 2.6 months (SD: 4.5 mo). The estimated probability of DRT survival at 2 months was 91% (95% CI: 83%-100%) in nonirradiated patients and 65% (95% CI: 48%-88%) in irradiated patients. In the 55 patients with a bony wound base, preoperative head radiation was associated with a higher likelihood of DRT loss (hazard ratio: 11). Half the irradiated defects experienced uncomplicated total wound closure using Integra Wound Matrix Dressing with or without second-stage reconstruction. CONCLUSIONS: Dermal regeneration template can offer durable coverage in nonirradiated scalp defects. Although DRT loss is more likely in irradiated scalp defects, successful DRT-based reconstruction is possible in select cases.

The combined risk predictive power of frailty and hypoalbuminemia in free tissue flap reconstruction: A cohort study of 34,571 patients from the NSQIP database.

INTRODUCTION: Significant morbidity and mortality are hallmarks of the functional decline seen in physically frail patients. The modified frailty index 5 (mFI-5) represents a risk predictor score that has been validated as a comorbidity-based scale in surgery. Serum albumin levels of <3.5 g/dL (hypoalbuminemia) have also been implicated with poor postoperative outcomes. However, the association between these two parameters remains to be investigated. We aimed to elucidate the interdependence of preoperative albumin levels and frailty, as evaluated by the mFI-5 score, and its reliability to prognosticate postoperative results in free flap reconstruction (FFR). METHODS: We conducted a multicenter, retrospective cohort study and accessed the ACS National Surgical Quality Improvement Program (ACS-NSQIP) from 2008 to 2021. We identified all adult patients (≥18 years of age) who underwent a FFR. We extracted perioperative data and lab values including albumin. Multivariable linear and logistic regression analyses were performed to identify independent risk predictors. Main outcomes involved mortality, length of hospital stay, reoperation, medical and surgical complications, and discharge destination within the 30-day postoperative period. RESULTS: A total of 34,571 patients were included in the study, with an average age of 53.9 years (standard deviation [SD] 12.2) and an average body mass index (BMI) of 28.8 (SD 6.1). Of these patients, 7484 were male (21.6%), whereas 22,363 (64.7%) had no frailty (mFI = 0). Additionally, 9466 patients had a frailty score of 1 (27.4%), 2505 had a score of 2 (7.2%), 226 had a score of 3 (0.7%), and 11 had a score of 4 or higher (0.0%). Albumin levels were available for 16,250 patients (47.0%), and among them, 1334 (8.2%) had hypoalbuminemia. Regression analyses showed that higher mFI scores were independent predictors of any, surgical, and medical complications, as well as increased rates of reoperations, unplanned readmissions, and prolonged hospital stays. Hypoalbuminemia independently predicted any, surgical, and medical complications, and higher mortality, reoperation, and longer hospital stay. When both frailty and albumin levels (mFI-5 and albumin) were considered together, this combined assessment was found to be a more accurate predictor of all major outcomes (any, medical and surgical complications, mortality, and reoperation). Further, our analysis identified a weak negative correlation between serum albumin levels and mFI scores (Spearman R: -.1; p < .0001). CONCLUSION: In conclusion, this cohort study highlights the association of hypoalbuminemia with adverse postoperative outcomes, including those not directly related to frailty. Simultaneously, higher mFI scores independently predicted outcomes not associated with hypoalbuminemia. Stemming from these findings, we recommend considering both serum albumin levels and frailty in patients receiving FFR. This perioperative algorithm may help provide more individualized planning including multidisciplinary care and pre and posthabilitation.

Dermal Regeneration Template in the Management and Reconstruction of Burn Injuries and Complex Wounds: A Review.

Background: Dermal scaffolds have created a paradigm shift for burn and wound management by providing improved healing and less scarring, while improving cosmesis and functionality. Dermal regeneration template (DRT) is a bilayer membrane for dermal regeneration developed by Yannas and Burke in the 1980s. The aim of this review is to summarize clinical evidence for dermal scaffolds focusing on DRT for the management and reconstruction of burn injuries and complex wounds. Methods: A comprehensive search of PubMed was performed from the start of indexing through November 2022. Articles reporting on DRT use in patients with burns, limb salvage, and wound reconstruction were included with focus on high-level clinical evidence. Results: DRT has become an established alternative option for the treatment of full-thickness and deep partial-thickness burns, with improved outcomes in areas where cosmesis and functionality are important. In the management of diabetic foot ulcers, use of DRT is associated with high rates of complete wound healing with a low risk of adverse outcomes. DRT has been successfully used in traumatic and surgical wounds, showing particular benefit in deep wounds and in the reconstruction of numerous anatomical sites. Conclusions: Considerable clinical experience has accrued with the use of DRT beyond its original application for thermal injury. A growing body of evidence from clinical studies reports the successful use of DRT to improve clinical outcomes and quality of life across clinical indications at a number of anatomical sites.

The long-term intercorrelation between post-burn pain, anxiety, and depression: a post hoc analysis of the "RE-ENERGIZE" double-blind, randomized, multicenter placebo-controlled trial.

BACKGROUND: Despite the growing prevalence of burn survivors, a gap persists in our understanding of the correlation between acute burn trauma and the long-term impact on psychosocial health. This study set out to investigate the prevalence of long-term pain and symptoms of anxiety and depression in survivors of extensive burns, comparing this to the general population, and identify injury and demographic-related factors predisposing individuals to psychosocial compromise. METHODS: RE-ENERGIZE was an international, double-blinded, randomized-controlled trial that enrolled 1200 patients with partial- or full-thickness burns that required surgical treatment. For the post hoc analysis, we excluded participants who did not complete the Short Form Health Survey (SF-36) questionnaire. Normative data were taken from the 2021 National Health Interview Survey dataset. Propensity score matching was performed using the nearest-neighbor 1-to-1 method, and the two cohorts were compared in terms of chronic pain, and symptoms of anxiety and depression. A multivariable analysis was performed on the burns cohort to identify factors predicting post-discharge pain and symptoms of anxiety and depression. RESULTS: A total of 600 burn patients and 26,666 general population adults were included in this study. Following propensity score matching, both groups comprised 478 participants each, who were predominately male, white, overweight and between 20 and 60 years old. Compared to the general population, burn patients were significantly more likely to report the presence of moderate and a lot of pain (p = 0.002). Symptoms of anxiety were significantly higher in the burn population in two of four levels (most of the time; some of the time; p < 0.0001 for both). Responders in the burn population were significantly less likely to report the absence of depressive symptoms (p < 0.0001). Burn patients were also significantly more likely to report that their mental health affects their social life. TBSA, history of depression, and female sex were identified as independently associated factors for pain, anxiety, and depressive symptoms. The presence of chronic pain and anxiety symptoms independently predicted for symptoms of depression. CONCLUSIONS: Analyzing the largest multicenter cohort of patients with extensive burns, we find that burn injury is associated with chronic pain, and symptoms of anxiety and depression. In addition, TBSA-burned and history of depression directly correlate with the prevalence of chronic pain, and symptoms of anxiety and depression. Finally, pain, and symptoms of anxiety and depression are interrelated and may have interactive effects on the process of recovery following burn injury. Burn patients would, therefore, benefit from a multidisciplinary team approach with early mobilization of pain and mental health experts, in order to promptly prevent the development of psychosocial challenges and their consequences.

An ACS-NSQIP Data Analysis of 30-Day Outcomes Following Surgery for Bell's Palsy.

BACKGROUND: There exists a paucity of large-scale, multi-institutional studies that investigate the outcomes of surgery for Bell's palsy (BP). Here, we utilize a large, multi-institutional database to study the risk factors and early-stage outcomes following surgical procedures in BP. METHODS: We reviewed the American College of Surgeons National Surgical Quality Improvement Program database (2008-2019) to identify patients who underwent surgery for the diagnosis of BP. We extracted data on comorbidities and preoperative blood values, and 30-day postoperative outcomes. RESULTS: Two hundred fifty-seven patients who underwent surgery for BP symptoms over the 12-year review period were identified. Muscle grafts (n=50; 19%) and fascial grafts (n=48; 19%) accounted for the majority of procedures. The most common comorbidities were hypertension (n=89; 35%) and obesity (n=79; 31%). Complications occurred in 26 (10.1%) cases. Additionally, length of hospital stay was significantly associated with both surgical and medical complications (3.9±4.7 versus 1.5±2.0; P <0.01) and (3.2±3.8 versus 1.4±2.0; P <0.01), respectively. Preoperative creatinine, blood urea nitrogen, and alkaline phosphatase were identified as potential predictors of poor postoperative outcomes. CONCLUSION: Based on multi-institutional analysis, complication rates following surgery for BP were found to be overall low and seen to correlate with length of hospital stay. Reoperations and readmissions were the most frequent complications after surgery for BP. The preoperative evaluation of routine laboratory values may help refine patient eligibility and risk stratification. In addition, our findings call for future large-scale prospective studies in the field of facial palsy surgery to further improve the quality of care and optimize perioperative protocols.

Empiric flap coverage for the pneumonectomy stump: How protective is it? A single-institution cohort study.

OBJECTIVE: To evaluate the impact of empiric tissue flaps on bronchopleural fistula (BPF) rates after pneumonectomy. METHODS: Patients who underwent pneumonectomy between January 2001 and December 2019 were included. Primary end point was development of BPF. Secondary end points were impact of flap type on BPF rates, time to BPF development, and perioperative mortality. RESULTS: During the study period, 383 pneumonectomies were performed; 93 were extrapleural pneumonectomy. Most pneumonectomy cases had empiric flap coverage, with greater use in right-sided operations (right: 97%, 154/159; left: 80%, 179/224, P < .001). Empiric flaps harvested included intercostal, latissimus dorsi, serratus anterior, omentum, pectoralis major, pericardial fat/thymus, pericardium, and pleura. BPF occurred in 10.4% of the entire cohort but decreased to 6.6% when extrapleural pneumonectomy cases were excluded; 90% (36/40) of BPFs occurred on the right side (P < .001). Median time to develop BPF was 63 days, and 90-day mortality was greater in patients with BPF (12.5% BPF vs 7.4% non-BPF, P < .0001). Intercostal muscle had the lowest rate of BPF (4.5%), even in right-sided operations (8.7%). In contrast, larger muscle flaps such as latissimus dorsi (21%) and serratus anterior (33%) had greater rates of BPF, but the sample size was small in these cohorts. CONCLUSIONS: Empiric bronchial stump coverage should be performed in all right pneumonectomy cases due to greater risk of BPF. In our series, intercostal muscle flaps had low BPF rates, even in right-sided operations. Coverage of the left pneumonectomy stump is unnecessary due to low incidence of BPF in these cases.

Phototherapy Restores Deficient Type I IFN Production and Enhances Antitumor Responses in Mycosis Fungoides.

Transcriptional profiling demonstrated markedly reduced type I IFN gene expression in untreated mycosis fungoides (MF) skin lesions compared with that in healthy skin. Type I IFN expression in MF correlated with antigen-presenting cell-associated IRF5 before psoralen plus UVA therapy and epithelial ULBP2 after therapy, suggesting an enhancement of epithelial type I IFN. Immunostains confirmed reduced baseline type I IFN production in MF and increased levels after psoralen plus UVA treatment in responding patients. Effective tumor clearance was associated with increased type I IFN expression, enhanced recruitment of CD8+ T cells into skin lesions, and expression of genes associated with antigen-specific T-cell activation. IFNk, a keratinocyte-derived inducer of type I IFNs, was increased by psoralen plus UVA therapy and expression correlated with upregulation of other type I IFNs. In vitro, deletion of keratinocyte IFNk decreased baseline and UVA-induced expression of type I IFN and IFN response genes. In summary, we find a baseline deficit in type I IFN production in MF that is restored by psoralen plus UVA therapy and correlates with enhanced antitumor responses. This may explain why MF generally develops in sun-protected skin and suggests that drugs that increase epithelial type I IFNs, including topical MEK and EGFR inhibitors, may be effective therapies for MF.

Racial disparities in surgical outcomes after mastectomy in 223 000 female breast cancer patients: a retrospective cohort study.

BACKGROUND: Breast cancer mortality and treatment differ across racial groups. It remains unclear whether such disparities are also reflected in perioperative outcomes of breast cancer patients undergoing mastectomy. STUDY DESIGN: The authors reviewed the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database (2008-2021) to identify female patients who underwent mastectomy for oncological purposes. The outcomes were stratified by five racial groups (white, Black/African American, Asian, American Indian/Alaska Native, and Native Hawaiian/Pacific Islander) and included 30-day mortality, reoperation, readmission, surgical and medical complications, and non-home discharge. RESULTS: The study population included 222 947 patients, 68% ( n =151 522) of whom were white, 11% ( n =23 987) Black/African American, 5% ( n =11 217) Asian, 0.5% ( n =1198) American Indian/Alaska Native, and 0.5% ( n =1018) Native Hawaiian/Pacific Islander. While 136 690 (61%) patients underwent partial mastectomy, 54 490 (24%) and 31 767 (14%) women received simple and radical mastectomy, respectively. Overall, adverse events occurred in 17 222 (7.7%) patients, the largest portion of which were surgical complications ( n =7246; 3.3%). Multivariable analysis revealed that being of Asian race was protective against perioperative complications [odds ratio (OR)=0.71; P <0.001], whereas American Indian/Alaska Native women were most vulnerable to the complication occurrence (OR=1.41; P <0.001). Black/African American patients had a significantly lower risk of medical (OR=0.59; P <0.001) and surgical complications (OR=0.60; P <0.001) after partial and radical mastectomy, respectively, their likelihood of readmission (OR=1.14; P =0.045) following partial mastectomy was significantly increased. CONCLUSION: The authors identified American Indian/Alaska Native women as particularly vulnerable to complications following mastectomy. Asian patients experienced the lowest rate of complications in the perioperative period. The authors' analyses revealed comparable confounder-adjusted outcomes following partial and complete mastectomy between Black and white races. Their findings call for care equalization in the field of breast cancer surgery.

The significance of timing in breast reconstruction after mastectomy: An ACS-NSQIP analysis.

BACKGROUND: A variety of breast reconstruction (BR) options are available. The significance of timing on outcomes remains debated. This study aims to compare complications in breast cancer patients undergoing implant-based and autologous BR immediately after mastectomy or at a delayed time point. METHODS: We reviewed the ACS-NSQIP database (2008-2021) to identify all female patients who underwent BR for oncological purposes. Outcomes were stratified by technique (implant-based versus autologous) and timing (immediate versus delayed), and included 30-day mortality, reoperation, (unplanned) readmission, and surgical and medical complications. RESULTS: A total of 21,560 patients were included: 11,237 (52%) implant-based (9791/87% immediate, 1446/13% delayed) and 10,323 (48%) autologous (8378/81% immediate, 1945/19% delayed). Complications occurred in 3666 (17%) patients (implant-based: n = 1112/11% immediate, n = 64/4.4% delayed cohorts; Autologous: n = 2073/25% immediate, n = 417/21% delayed cohorts). In propensity score weighting (PSW) analyses, immediate BR was associated with significantly more complications than delayed BR (p < 0.0001). This was the case for both implant-based and autologous BR, with a greater difference between the two time points noted in implant-based. Confounder-adjusted multivariable analyses confirmed these results. CONCLUSION: At the 30-day time point, delayed BR is associated with significantly lower complication rates than immediate BR, in both the implant-based and autologous cohorts. These findings are not a blanket recommendation in favor of immediate and/or delayed BR. Instead, our insights may guide surgeons and patients in decision-making and help refine patients' eligibility in a case-by-case workup.

PPARγ agonist treatment reduces fibroadipose tissue in secondary lymphedema by exhausting fibroadipogenic PDGFRα+ mesenchymal cells.

Secondary lymphedema occurs in up to 20% of patients after lymphadenectomy performed for the surgical management of tumors involving the breast, prostate, uterus, and skin. Patients develop progressive edema of the affected extremity due to retention of protein-rich lymphatic fluid. Despite compression therapy, patients progress to chronic lymphedema in which noncompressible fibrosis and adipose tissue are deposited within the extremity. The presence of fibrosis led to our hypothesis that rosiglitazone, a PPARγ agonist that inhibits fibrosis, would reduce fibrosis in a mouse model of secondary lymphedema after hind limb lymphadenectomy. In vivo, rosiglitazone reduced fibrosis in the hind limb after lymphadenectomy. Our findings verified that rosiglitazone reestablished the adipogenic features of TGF-ß1-treated mesenchymal cells in vitro. Despite this, rosiglitazone led to a reduction in adipose tissue deposition. Single-cell RNA-Seq data obtained from human tissues and flow cytometric and histological evaluation of mouse tissues demonstrated increased presence of PDGFRα+ cells in lymphedema; human tissue analysis verified these cells have the capacity for adipogenic and fibrogenic differentiation. Upon treatment with rosiglitazone, we noted a reduction in the overall quantity of PDGFRα+ cells and LipidTOX+ cells. Our findings provide a framework for treating secondary lymphedema as a condition of fibrosis and adipose tissue deposition, both of which, paradoxically, can be prevented with a pro-adipogenic agent.

Regulatory T cells in skin regeneration and wound healing.

As the body's integumentary system, the skin is vulnerable to injuries. The subsequent wound healing processes aim to restore dermal and epidermal integrity and functionality. To this end, multiple tissue-resident cells and recruited immune cells cooperate to efficiently repair the injured tissue. Such temporally- and spatially-coordinated interplay necessitates tight regulation to prevent collateral damage such as overshooting immune responses and excessive inflammation. In this context, regulatory T cells (Tregs) hold a key role in balancing immune homeostasis and mediating cutaneous wound healing. A comprehensive understanding of Tregs' multifaceted field of activity may help decipher wound pathologies and, ultimately, establish new treatment modalities. Herein, we review the role of Tregs in orchestrating the regeneration of skin adnexa and catalyzing healthy wound repair. Further, we discuss how Tregs operate during fibrosis, keloidosis, and scarring.

The surgical patient of yesterday, today, and tomorrow-a time-trend analysis based on a cohort of 8.7 million surgical patients.

BACKGROUND: Global healthcare delivery is challenged by the aging population and the increase in obesity and type 2 diabetes. The extent to which such trends affect the cohort of patients the authors surgically operate on remains to be elucidated. Comprising of 8.7 million surgical patients, the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database can be analyzed to investigate the echo of general population dynamics and forecast future trends. MATERIAL AND METHODS: The authors reviewed the ACS-NSQIP database (2008-2020) in its entirety, extracting patient age, BMI, and diabetes prevalence. Based on these data, the authors forecasted future trends up to 2030 using a drift model. RESULTS: During the review period, median age increased by 3 years, and median BMI by 0.9 kg/m2. The proportion of patients with overweight, obesity class I, and class II rates increased. The prevalence of diabetes rose between 2008 (14.9%) and 2020 (15.3%). The authors forecast the median age in 2030 to reach 61.5 years and median BMI to climb to 29.8 kg/m2. Concerningly, in 2030, eight of ten surgical patients are projected to have a BMI above normal. Diabetes prevalence is projected to rise to 15.6% over the next decade. CONCLUSION: General population trends echo in the field of surgery, with the surgical cohort aging at an alarmingly rapid rate and increasingly suffering from obesity and diabetes. These trends show no sign of abating without dedicated efforts and call for urgent measures and fundamental re-structuring for improved future surgical care.