Prophylactic Muscle Flaps in Primary Vascular Procedures of the Groin.

BACKGROUND: Complications following vascular procedures involving the groin can lead to significant morbidity. Achieving stable soft tissue coverage over sites of revascularization can help mitigate complications. Prior evidence supports the use of muscle flaps in reoperative groins and in high risk patient populations to reduce postoperative complications. Data regarding the use of prophylactic muscle flap coverage of the groin is lacking. Therefore, the purpose of this study is to evaluate the effect of immediate prophylactic muscle flap coverage of vascular wounds involving the groin. METHODS: A retrospective cohort study was performed on all patients undergoing primary open vascular procedures involving the groin for occlusive, aneurysmal, or oncologic disease between 2014 and 2020 at a single institution where plastic surgery was involved in closure. Patient demographics, comorbidities, surgical details, and postoperative complications were compared between patients who had sartorius muscle flap coverage of the vascular repair versus layered closure alone. RESULTS: A total of 133 consecutive groins were included in our analysis. A sartorius flap was used in 115 groins (86.5%) and a layered closure was used in 18 (13.5%). Wound breakdown was similar between groups (25.2% sartorius vs. 38.9% layered closure, P = 0.26). However, the rate of reoperation was significantly higher in the layered closure group (50.0% vs. 12.2%, P < 0.01). Among patients who experienced wound breakdown (N = 36), a larger proportion of layered closure patients required operative intervention (71.4% vs. 20.7%, P = 0.02). Other rates of complications were not statistically different between groups. CONCLUSIONS: In patients undergoing primary open vascular procedures involving the groin, patients who underwent prophylactic sartorius muscle flap closure had lower rates of reoperation. Although incisional breakdown was similar between the groups overall, the presence of a vascularized muscle flap overlying the vascular repair was associated with reduced need for reoperation and allowed more wounds to be managed with local wound care alone. Consideration should be given to this low morbidity local muscle flap in patients undergoing vascular procedures involving the groin.

Diagnosis and Treatment of Lymphatic Complications of the Groin Following Open Lower Extremity Revascularization with Plastic Surgery Closure.

INTRODUCTION: Lymphatic complications following vascular procedures involving the groin require prompt treatment to limit morbidity. Several treatments have been described, including conservative management, aspiration, sclerotherapy, and direct lymphatic ligation with or without a muscle flap have been described. To date, there is no data indicating which treatment results in the shortest time to recovery. We sought to address this gap by conducting a retrospective cohort study. METHODS: We reviewed all patients who developed a lymphatic complication after undergoing an open revascularization procedure in the groin between 2014 and 2020 in which plastic surgery was involved in the closure. A control group consisted of patients from the same timespan who did not develop a lymphatic complication. Demographics, comorbidities, operative details, and outcomes were compared between these groups. For cases identified with a lymphatic complication, the method of diagnosis, culture data, and treatment details were collected, and outcomes were compared for surgical management versus sclerotherapy. RESULTS: There were 27 lymphatic complications and 60 control patients. The complication group had a higher incidence of aortofemoral bypass (25.8% vs. 8.3%, P = 0.04), and a lower incidence of femoral-to-distal bypass (11.1% vs. 45.0%, P < 0.01). Daily drain output volume from postoperative days 1-5, and days 6-10, was significantly higher in the complication group than in the controls (194.0 vs. 44.0, P < 0.01; and 429.5 vs. 35.0, P < 0.01, respectively). In the lymphatic leak group, 16 patients (59.3%) had surgical treatment and six (22.2%) had sclerotherapy. Of those who had surgery, 71.4% had successful outcomes without the need for an additional intervention, whereas all of the patients analyzed who were treated with sclerotherapy had successful outcomes without further intervention. The average time to resolution was significantly shorter for surgery than for sclerotherapy (38.7 vs. 86.0 days, P = 0.03). CONCLUSIONS: Daily postoperative drain volume can assist with early diagnosis of a lymphatic leak in the groin following an open revascularization procedure. Sclerotherapy and surgery were each successful, but surgery resulted in significantly shorter times to resolution. In the appropriate candidates, surgery should be considered first line management of a lymphatic leak.

CdiA promotes receptor-independent intercellular adhesion.

CdiB/CdiA proteins mediate inter-bacterial competition in a process termed contact-dependent growth inhibition (CDI). Filamentous CdiA exoproteins extend from CDI(+) cells and bind specific receptors to deliver toxins into susceptible target bacteria. CDI has also been implicated in auto-aggregation and biofilm formation in several species, but the contribution of CdiA-receptor interactions to these multi-cellular behaviors has not been examined. Using Escherichia coli isolate EC93 as a model, we show that cdiA and bamA receptor mutants are defective in biofilm formation, suggesting a prominent role for CdiA-BamA mediated cell-cell adhesion. However, CdiA also promotes auto-aggregation in a BamA-independent manner, indicating that the exoprotein possesses an additional adhesin activity. Cells must express CdiA in order to participate in BamA-independent aggregates, suggesting that adhesion could be mediated by homotypic CdiA-CdiA interactions. The BamA-dependent and BamA-independent interaction domains map to distinct regions within the CdiA filament. Thus, CdiA orchestrates a collective behavior that is independent of its growth-inhibition activity. This adhesion should enable 'greenbeard' discrimination, in which genetically unrelated individuals cooperate with one another based on a single shared trait. This kind-selective social behavior could provide immediate fitness benefits to bacteria that acquire the systems through horizontal gene transfer.

The Effect of Pectoral Nerve Blocks on Opioid Use and Postoperative Pain in Masculinizing Mastectomy: A Randomized Controlled Trial.

BACKGROUND: Bilateral masculinizing mastectomy is the most common gender-affirmation operation performed. Currently, there is lack of data regarding intraoperative and postoperative pain control for this population. It is the authors' aim to study the effects of the pectoral nerve (Pecs) I and II regional nerve blocks in patients undergoing masculinizing mastectomy. METHODS: A randomized, double-blind, placebo-controlled trial was performed. Patients undergoing bilateral gender-affirmation mastectomy were randomized to receive either a Pecs block with ropivacaine or placebo injection. The patient, surgeon, and anesthesia team were blinded to the allocation. Intraoperative and postoperative opioid requirements were collected and recorded as morphine milligram equivalents (MME). Participants recorded postoperative pain scores at specific time points on the day of surgery through postoperative day 7. RESULTS: Fifty patients were enrolled between July of 2020 and February of 2022. Twenty-seven were randomized to the intervention group and 23 to the control group, with 43 patients undergoing analysis. There was no significant difference in intraoperative MME between the Pecs block group and the control group (9.8 versus 11.1; P = 0.29). In addition, there was no difference in postoperative MME between the groups (37.5 versus 40.0; P = 0.72). Postoperative pain scores were also similar between the groups at each specified time point. CONCLUSIONS: There was no significant reduction in opioid consumption or postoperative pain scores in patients undergoing bilateral gender-affirmation mastectomy who received a regional anesthetic when compared with placebo. In addition, a postoperative opioid-sparing approach may be appropriate for patients undergoing bilateral masculinizing mastectomy. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, I.

Radiographic evaluation of midterm failure rates following metal-on-metal hip resurfacing.

This prospective study examined patient characteristics and radiographic findings for 89 subjects undergoing total hip resurfacing. Thirteen (14.6%) of 89 hips have required revision. Female sex, smaller implant size, and diagnosis of osteonecrosis were associated with lower device survival. No significant differences in acetabular cup angle and stem angle were observed between revised and nonrevised hips. Revision rates for the first 25 hips were 24% and 8% for the last 64 hips. Females accounted for 56% of subjects 1 to 25 and 23% of subjects 26 to 89. Despite representing only 33% of included subjects, females accounted for 62% of revision procedures. The lower device survival proportion in subjects 1 to 25 could not be attributed to acetabular or femoral component malpositioning and can likely be explained by a significantly higher proportion of females enrolled early in the study.

Receptor polymorphism restricts contact-dependent growth inhibition to members of the same species.

UNLABELLED: Bacteria that express contact-dependent growth inhibition (CDI) systems outcompete siblings that lack immunity, suggesting that CDI mediates intercellular competition. To further explore the role of CDI in competition, we determined the target cell range of the CDIEC93 system from Escherichia coli EC93. The CdiAEC93 effector protein recognizes the widely conserved BamA protein as a receptor, yet E. coli EC93 does not inhibit other enterobacterial species. The predicted membrane topology of BamA indicates that three of its extracellular loops vary considerably between species, suggesting that loop heterogeneity may control CDI specificity. Consistent with this hypothesis, other enterobacteria are sensitized to CDIEC93 upon the expression of E. coli bamA and E. coli cells become CDIEC93 resistant when bamA is replaced with alleles from other species. Our data indicate that BamA loops 6 and 7 form the CdiAEC93-binding epitope and their variation between species restricts CDIEC93 target cell selection. Although BamA loops 6 and 7 vary dramatically between species, these regions are identical in hundreds of E. coli strains, suggesting that BamAEcoli and CdiAEC93 play a role in self-nonself discrimination. IMPORTANCE: Contact-dependent growth inhibition (CDI) systems are widespread among Gram-negative bacteria, enabling them to bind to neighboring bacterial cells and deliver protein toxins that inhibit cell growth. In this study, we tested the role of CDI in interspecies competition using intestinal isolate Escherichia coli EC93 as an inhibitor cell model. Although E. coli EC93 inhibits different E. coli strains, other bacterial species from the intestine are completely resistant to CDI. We show that resistance is due to small variations in the CDI receptor that prevent other species from being recognized as target cells. CDI receptor interactions thus provide a mechanism by which bacteria can distinguish siblings and other close relatives (self) from more distant relatives or other species of bacteria (nonself). Our results provide a possible means by which antimicrobials could be directed to one or only a few related bacterial pathogens by using a specific receptor "zip code."