Surgical Pocket Research Articles

Utilizing a Porcine Fat Grafting Model for Translational Research: Surgical Approach, Complications, and Expected Outcomes

Autologous fat grafting, or lipotransfer, is an important surgical approach to relocate adipose tissue within an individual to create volume. While used extensively in plastic and reconstructive surgery, significant drawbacks exist, including unpredictable volume retention. Thus, considerable research has been undertaken to identify surgical or therapeutic approaches that improve outcomes, primarily utilizing a xenograft immunocompromised mouse model. Large animal models are an important step in translating preclinical laboratory studies to the clinic, and previous studies utilizing pigs have been applied successfully for fat grafting research, but protocol variability exists across studies, and no previous publication has adequately described the impact of the swine breed on the experimental outcomes. In this report, we provide information on the critical attributes of the swine fat grafting model, including the following: (1) model selection; (2) donor site and surgical harvest approach; (3) tissue processing; (4) recipient site location and preparation; (5) post-operative care; and (6) longitudinal fat grafting assessments. Our experience comparing the use of Yorkshire and Yucatan breeds in our model showed that Yorkshire adipose tissue was fibrotic, extremely difficult to obtain through liposuction, and labor intensive to process into injectable formats. Alternatively, Yucatan adipose was more similar to human tissue, could be readily obtained through the surgical excision of inguinal fat pads, was amenable to mincing with surgical scissors, and yielded injectable tissue with a 95% efficiency. We determined that generation of a surgical pocket reduced the graft migration and spread, consequently facilitating the graft retrieval without significantly impacting retention. Using 5 cc grafts, the ultimate 3-month volume retention in 16 grafts was 19% ± 17% (or 1.14 cc ± 1.08 cc). While the use of ultrasound did not readily enable graft volume approximation during the study, it was a useful method to visualize the graft placement and ensure injection into the subcutaneous adipose layers.

Comparing the efficacy of antimicrobial pocket-irrigation protocols in an in vivo breast implant infection model

Breast implant infection and biofilm formation are major concerns in reconstructive and esthetic breast surgery, with significant medical and economic consequences. Staphylococcus is the common pathogen, with rapidly increasing rates of methicillin-resistant Staphylococcus aureus (MRSA). There is no consensus on prevention practices. This study compares the effect of several pocket irrigation and antibiotic prophylaxis regimens on implant colonization and biofilm formation in an established rat model of MRSA-infected silicone breast implants. Silicone discs were inserted in a sub-pectoral pocket in 57 rats (114 implants). Implant infection was induced by injection of free planktonic MRSA into the surgical pocket. Rats were allocated to study groups treated by different antimicrobial protocols: pocket irrigation with vancomycin, povidone-iodine, or saline. Each group was divided into subgroups treated with or without additional peri-operative systemic vancomycin. Implant colonization or overt infection was assessed at post-operative day 14 both clinically and by cultures. Pocket irrigation with vancomycin prevented contamination in 87% of implants. Irrigation and systemic vancomycin prevented contamination in 100% of implants with no difference between a single preoperative dose and a 48-h regimen. Systemic vancomycin alone or irrigation with povidone-iodine alone resulted in 100% contamination rates. In this in vivo model, combination of systemic vancomycin with vancomycin pocket irrigation was the most effective regimen, preventing contamination in 100% of implants. Continuation of post-operative antibiotic treatment showed no added advantage.

47. Flowable Decellularized Dermal Hydrogel Improves Integration of Acellular Dermal Matrices

PURPOSE: Acellular dermal matrices (ADM) have revolutionized pre-pectoral implant-based breast reconstruction allowing for improved pocket control and more rapid expansion but with the drawback of an increased risk of seroma that can lead to major complications including implant loss. The majority of these complications are a result of delayed or insufficient wound healing and integration of the ADM. ADM bio-integration can be accelerated by increasing the surface area of the ADM:host soft tissue interface. To address the issue of persistent contact of the ADM with the patient, we investigated the application of a hydrogel, derived from ADM to increase the conduction of the cells and molecular signals and increase vascularization, is critical to biointegration. METHODS: C57bl/6 mice received bilateral subcutaneous pockets. A 5mm diameter ADM implant was placed into each pocket and into one, 0.5 mL of decellularized dermal hydrogel was injected. Implants were harvested at terminal endpoints at 1, 3, and 6 weeks. Flow cytometry was performed to assess a panel of 12 macrophage markers (pan-, M1, M2, or transition) to evaluate inflammatory effects. Immunohistochemical staining for vimentin was used to assess fibroblast migration into the ADM. Hematoxylin and eosin (H&E) staining of implant cross sections was performed for pathological analysis of fibrosis via capsule formation. Capsule thickness, cellularity, foreign bodies, and smooth muscle actin (SMA) were graded (0 = none, 1 = mild, 2 = moderate, 3 = severe). RESULTS: H&E staining demonstrated that the dermal hydrogel persisted adjacent to the ADM implant. Flow cytometry results demonstrated that DPD hydrogel and ADM did not elicit an increased macrophage response compared to ADM implants alone. Vimentin expression demonstrated an upward trend in fibroblast infiltration from 3 to 6, with the dermal hydrogel group fibroblast increase outpacing that of the ADM control. Pathological analysis showed minimal capsule formation and no significant increase in fibrosis between hydrogel and no hydrogel groups. CONCLUSIONS: Our dermal hydrogel was able to flow easily into the surgical pocket, polymerized at physiological temperatures, and remained in place over the course of 6 weeks, demonstrating its potential to bridge the gap between ADM and the overlying skin envelope within human breast reconstructions. Our murine model revealed that the dermal hydrogel did not lead to an increased inflammatory immune response, with no statistical difference in fibrosis scores between t ADM-only implants. Although not statistically significant, immunohistochemistry quantifying the amount of vimentin present in the hydrogel-ADM complex showed promising trends with ADM integration into host tissue. Future work will include expansion of the model to incorporate radiation in order to examine the ability of the dermal hydrogel to aid in wound healing and ADM integration within an environment mirroring that seen in irradiated mastectomy cases.

The effect of bromelain in periodontal surgery: a double-blind randomized placebo-controlled trial

BackgroundPeriodontitis is a persistent inflammatory condition. Eliminating the infection and reducing its risk factors are the first steps in treating periodontitis. When the anti-infective therapy is complete, there may still be deep periodontal pockets and prolonged inflammation. Surgical pocket reduction or elimination is indicated under these circumstances. We aimed to evaluate the effect of bromelain on bleeding on probing (BOP), gingival index (GI), and plaque index (PI) after pocket elimination surgery.MethodsThis double-blind randomized placebo-controlled trial included 28 candidates for pocket elimination surgery referred to the private office of a periodontist in Bandar Abbas, Iran, from April 18 to August 18, 2021. Patients’ general characteristics, such as age and sex, were recorded. Additionally, periodontal indices including BOP, PI, GI, and pocket probing depth (PPD) were evaluated in all subjects. All patients underwent pocket elimination surgery. Afterwards, they were randomized into two groups. The first group received 500 mg Anaheal (bromelain) capsules twice a day before meal for one week. The second group received placebo, prepared in similar shape and color by the same pharmaceutical company. BOP, PI, GI, and PPD were assessed four weeks after completion of the treatment course (five weeks after surgery).ResultsFour weeks after intervention, BOP was significantly lower with Anaheal compared to placebo (0% vs. 35.7%, P = 0.014). However, there was no significant difference in GI between groups (P = 0.120). Mean PI was lower (17.71 ± 2.12 vs. 18.28 ± 2.49) and mean PPD higher (3.10 ± 0.71 vs. 2.64 ± 0.45) in the Anaheal group, but the differences did not reach statistically significant levels (P = 0.520 and P = 0.051, respectively).ConclusionsOne-week treatment with Anaheal at a dose of 1 g/d after pocket elimination surgery resulted in significantly lower BOP compared to placebo.Trial registrationIranian Registry of Clinical Trials (IRCT), IRCT20201106049289N1. Registered 06/04/2021. Registered prospectively, https://www.irct.ir/trial/52181.

Betadine Soaking of Silicone Coupons Minimally Impacts Acellular Dermal Matrix Incorporation in a Preclinical Primate Model.

Microbial pathogens local to prosthetic breast devices may promote infection, inflammation, and capsular contracture. Although antimicrobial solutions have been used, their effects on human acellular dermal matrix (HADM) incorporation when used with prosthetic devices are unknown. The authors' objective was to histologically assess the effect of 10% povidone iodine (PI)-saturated tissue expander (TE) exposure on HADM biological response in a primate model. They hypothesized that PI exposure would not negatively affect the HADM biological response. Samples (1.5 × 1.5 cm) from smooth silicone TEs were saturated in saline or PI for 2 minutes and sutured to HADM to create HADM/TE constructs. Primates implanted subcutaneously with saline ( n = 9) and PI-treated HADM/TE ( n = 9) construct pairs were evaluated histologically for biological response after 2 or 4 weeks by means of a host response scoring scale (1 to 9), including recellularization, neovascularization, and inflammation. Inflammatory cells (eosinophils, lymphocytes, neutrophils, histiocytes, foreign-body giant cells) and evidence of HADM remodeling (fibroblasts, vessels) were further evaluated by means of a cell-specific scoring scale (0 to 4) and corroborated by immunostaining (CD3, CD20, CD68, FSP-1, collagen type IV). Mean histology scores were similar between saline- and PI-exposed HADM at 2 weeks (5.3 ± 0.9 and 5.6 ± 0.5; P = 0.52) and 4 weeks (4.6 ± 1.0 and 4.2 ± 0.9; P = 0.44). There was no difference in inflammatory cell presence at 2 and 4 weeks between groups. Fibroblast infiltration differences were insignificant between groups but exhibited trends toward an increase between time points for saline (1.6 ± 0.7 to 1.8 ± 0.8) and PI (1.3 ± 0.8 to 1.8 ± 1.0) groups, suggesting HADM incorporation over time. Data suggest that HADM exposure to PI-treated TEs does not negatively affect inflammation, vascularization, recellularization, incorporation, or host response to HADM in this model. PI is a surgical pocket irrigant used to address bacterial colonization, but its impact on ADM incorporation is unknown. This study demonstrates similar biologic response to ADMs adjacent to PI- or saline-saturated TEs in a primate model.

925 THE TWIDDLER'S SYNDROME: A CASE REPORT

Abstract Introduction The Twiddler's syndrome is a rare condition of malfunctioning of a cardiovascular implantable elettronic device (CIED) due to the rotation of the device around its own long axis within its pocket. This brings to the leads wrapping around the device case and consequently dislocating, resulting in a deficit in sensing and pacing. Case Report We present the case of an 82-year-old woman, affect by atrial and conduction tissue disease for which was implanted a dual-chamber PaceMaker (PM). She arrived at the emergency department for asthenia and a traumatic syncopal episode, preceded by intense general malaise, nausea and vomiting. At EKG findings of electroinduced atrial rhythm, electroinduced ventricular rhythm with loss of capture and emergence of spontaneous rhythm, with subsequent resumption of capture. At device telemetry check, rise of ventricular and atrial pacing thresholds together with sporadic ventricular capture losses. Chest×Ray showed entanglement of leads around the PM case and retraction of the ventricular catheter. Therefore, the patient was admitted to the cardiology department, and the surgical pocket was revised with case extraction and leads debridement with subsequent optimization of their position. The next day, following device telemetry check, which showed good electrical parameters, and the follow-up chest X-Ray, which was normal, the patient was discharged. Conclusion All physicians, particularly cardiologists, must pay close attention to the evaluation of patients with CIEDs. First of all, meticulous analysis of the EKG must be performed, which is capable of showing loss of capture and abnormal QRS morphologies due to cardiac pacing at abnormal locations. In addition, it is necessary to perform the telemetry check of the device, infact findings of sensing deficits and/or elevation of pacing thresholds indicate device malfunctioning, which is not necessarily due to leads injuries. Displacement of the leads can be easily detected with a chest X-ray, always remembering to rule out the presence of Twiddler syndrome, however rare it may be.

Comparison of Breast Reconstruction Outcomes Using Oxychlorosene versus Triple Antibiotic Solution for Pocket Irrigation.

Background:Breast pocket irrigation with antiseptic solutions is performed to reduce contamination with breast implants. The optimal antiseptic irrigation solution and the efficacy of individual practices are unclear. Oxychlorosene sodium is frequently used at our institution. Oxychlorosene is bactericidal with a mechanism of action of oxidation and hypochlorination. The purpose of our study was to compare the outcomes of oxychlorosene sodium irrigation with triple antibiotic solution (TAS) in implant-based breast reconstruction.Methods:All patients who underwent implant-based reconstruction after mastectomy were reviewed. The primary predictive variable was type of solution used for pocket irrigation (TAS or oxychlorosene). Outcome variables included surgical site infection, device removal, and wound complications.Results:Between 2013 and 2018, 331 implant-based breast reconstructions were performed. Of these, 62% (n = 206) received oxychlorosene for surgical pocket irrigation (group I), and 38% (n = 125) received TAS (group II). Group I had an 11.7% (n = 24) 90-day surgical site infection rate, with 4.9% (n = 10) requiring oral antibiotics, 2.4% (n = 5) requiring intravenous antibiotics without device removal, and 4.4% (n = 9) requiring prosthetic removal. Group II had an 11.2% (n = 14) 90-day infection rate, with 5.6% (n = 7) requiring oral antibiotics, 2.4% (n = 3) requiring intravenous antibiotics without device removal, and 3.2% (n = 4) requiring removal (P = 0.90). When comparing the cost of oxychlorosene irrigation with TAS irrigation, oxychlorosene was less expensive.Conclusions:Oxychlorosene and TAS have similar surgical site infection rates in prosthetic breast reconstruction. Ease of preparation and cost make oxychlorosene a more favorable option for antibiotic irrigation in reconstructive breast surgery with prosthetic devices.

Access site bleeding complications comparing oral anticoagulation therapy with NOACs and VKAs in patients with atrial fibrillation undergoing cardiac implantable device intervention

Abstract Funding Acknowledgements Type of funding sources: None. Background Atrial fibrillation is frequent in patients undergoing cardiac implantable electronic device (CIED) intervention. Such population require oral anticoagulation therapy, which increases risk of procedure related bleeding. There is a lack on data on procedure-related bleeding outcome with non-vitamin K antagonist anticoagulants (NOACs) vs vitamin K antagonist anticoagulants (VKAs) in patients with AF undergoing CIED intervention. Study purpose Aim of the present stud was to evaluate whether NOACs have a safety benefit compared to VKAs in terms of fewer hemorrhagic complications at the site of CIED implant. Methods Consecutive AF patients receiving NOACs or VKAs at the time of CIED procedure were included in this observational, retrospective, monocentric investigation. Primary endpoint was the incidence of post-intervention clinically significant pocket hematoma. Multivariate analysis was performed to investigate the association between covariates and the primary endpoint. Results A total of 311 patients were enrolled, 146 on NOACs and 165 on VKAs. The incidence of pocket hematoma was 3.4% in the NOAC vs 13.3% in the VKA group (p=0.002) (Figure 1). Primary outcome-free survival at 30-days was 96.6 % in patients on NOACs and 86.0% in those on VKAs (p=0.019) (Figure 2). Multivariate analysis, adjusted by propensity-score calculation of inverse-probability-weighting, showed a significantly lower occurrence of pocket hematoma in patients receiving NOACs vs VKAs (HR 0.35, 95% CI 0.13-0.96, p=0.042). Such NOACs benefit was confirmed vs patients on VKAs without peri-procedural bridging with low-molecular weight heparin (HR 0.34, 95% CI 0.11-0.99, p=0.048). The incidence of pocket infection, surgical pocket evacuation, ischemic events and major bleeding complications at 30 days (secondary endpoints) was similar in the two groups. Conclusion Among patients with AF undergoing implantable cardiac defibrillator or pace-maker intervention, the use of NOACs vs VKAs is associated with significant reduction of post-procedural pocket hematoma, regardless of bridging with low molecular-weight heparin in the VKA group.

P12 SUBCUTANEOUS IMPLANTABLE CARDIOVERTER–DEFIBRILLATOR AFTER TRANSVENOUS LEAD EXTRACTION: SAFETY, EFFICACY AND OUTCOME

Abstract Background Subcutaneous implantable cardioverter defibrillator (S–ICD) is a suitable alternative for trans–venous–ICD (TV–ICD) patients underwent transvenous lead extraction (TLE) for any reason, but limited data are available about outcome of s–ICD patients implanted after TLE. Methods Thirty–six consecutive patients underwent TLE of TV–ICD and subsequent S–ICD implantation in our center were included in this prospective single–center observational study (72.2% male, median age 52 years–old). Results During a median follow-up of 31 months, 3 patients (8.3%) experienced appropriate therapy and 7 patients (19.4%) experienced complications including innapropriate therapy (IAT) (n = 4; 11.1%), pulse generator decubitus with no evidence of infection (n = 2; 5.5%) and ineffective therapy (n = 1; 2.7%). Reasons of IAT were: T–wave oversensing in one patient and extracardiac signals in the remaining 3 patients. Of note, 2 patients who experienced IAT had a left–ventricular assist device (LVAD) for refractory heart failure (HF). Premature device explantation and TV–ICD re–implantation occurred in 4 patients (11%) for pulse generator decubitus despite surgical pocket revisions (n = 2), for recurrent IAT despite reprogramming (n = 1) and ineffective therapy during arrhythmic storm (n = 1). Eight patients (22.2%) died, 3 patients (9%) underwent LVAD implantation due refractory HF during follow-up. Six patients died because of refractory HF, 1 patient died due to intracerebral hemorrhage and 1 due to sarcoidosis. There were no documented deaths associated with the procedure or the S–ICD system itself. No patient had the device removed because of a perceived need for antitachycardia pacing (ATP) or the necessity of pacing or cardiac resynchronization therapy despite 9 patients (25%) after TLE of a two–chamber ICD and one patient (3%) after TLE of a CRT–D. Univariate predictors of death included hypertension (HR 22.72; p = 0.02), diabetes (HR 10.64; p = 0.001), ischemic heart disease (HR 5.92; p = 0.01) and NYHA class > = II (p = 0.04). We did not observed any predictors for complications including IATs and device-related complications requiring surgical revision. Conclusions S–ICD implantaion after TLE of TV–ICD is safy and effective. Baseline clinical characterisctics including ischemic heart disease, diabetes, hypertension and NYHA class > = II are associated with worse survival.

Access Site Bleeding Complications with NOACs versus VKAs in Patients with Atrial Fibrillation Undergoing Cardiac Implantable Device Intervention.

There are no data on procedure-related bleeding outcome with non-vitamin K antagonist anticoagulants (NOACs) versus vitamin K antagonist anticoagulants (VKAs) in patients with atrial fibrillation (AF) undergoing cardiac implantable electronic device (CIED) intervention. Our aim was to evaluate whether NOACs have a safety benefit even in terms of fewer hemorrhagic complications at the site of CIED implant. Consecutive AF patients receiving NOACs or VKAs at the time of CIED procedure were included in this observational, retrospective, and monocentric investigation. Primary endpoint was the incidence of post-intervention pocket hematoma. A total of 311 patients were enrolled, 146 on NOACs, and 165 on VKAs. The incidence of pocket hematoma was 3.4% in the NOAC versus 13.3% in the VKA group (p = 0.002). Primary outcome-free survival at 30-days was 96.6% in patients on NOACs and 86.0% in those on VKAs (p = 0.019). Multivariate analysis, adjusted by propensity-score calculation of inverse-probability-weighting, showed a significantly lower occurrence of pocket hematoma in patients receiving NOACs versus VKAs (HR 0.35, 95% CI 0.13–0.96, p = 0.042). Such NOACs benefit was confirmed versus patients on VKAs without peri-procedural bridging with low-molecular-weight heparin (HR 0.34, 95% CI 0.11–0.99, p = 0.048). The incidence of pocket infection, surgical pocket evacuation, ischemic events, and major bleeding complications at 30 days (secondary endpoints) was similar in the two groups. In conclusion, our data suggest that, among patients with AF undergoing implantable cardiac defibrillator or pacemaker intervention, the use of NOACs versus VKAs may be associated with significant reduction of post-procedural pocket hematoma, regardless of bridging with low-molecular-weight heparin in the VKA group. These results are hypothesis generating and need to be confirmed in a specific randomized study.

In vivo Visualization of Pig Vagus Nerve "Vagotopy" Using Ultrasound.

Background: Placement of the clinical vagus nerve stimulating cuff is a standard surgical procedure based on anatomical landmarks, with limited patient specificity in terms of fascicular organization or vagal anatomy. As such, the therapeutic effects are generally limited by unwanted side effects of neck muscle contractions, demonstrated by previous studies to result from stimulation of (1) motor fibers near the cuff in the superior laryngeal and (2) motor fibers within the cuff projecting to the recurrent laryngeal.Objective: Conventional non-invasive ultrasound, where the transducer is placed on the surface of the skin, has been previously used to visualize the vagus with respect to other landmarks such as the carotid and internal jugular vein. However, it lacks sufficient resolution to provide details about the vagus fascicular organization, or detail about smaller neural structures such as the recurrent and superior laryngeal branch responsible for therapy limiting side effects. Here, we characterize the use of ultrasound with the transducer placed in the surgical pocket to improve resolution without adding significant additional risk to the surgical procedure in the pig model.Methods: Ultrasound images were obtained from a point of known functional organization at the nodose ganglia to the point of placement of stimulating electrodes within the surgical window. Naïve volunteers with minimal training were then asked to use these ultrasound videos to trace afferent groupings of fascicles from the nodose to their location within the surgical window where a stimulating cuff would normally be placed. Volunteers were asked to select a location for epineural electrode placement away from the fascicles containing efferent motor nerves responsible for therapy limiting side effects. 2-D and 3-D reconstructions of the ultrasound were directly compared to post-mortem histology in the same animals.Results: High-resolution ultrasound from the surgical pocket enabled 2-D and 3-D reconstruction of the cervical vagus and surrounding structures that accurately depicted the functional vagotopy of the pig vagus nerve as confirmed via histology. Although resolution was not sufficient to match specific fascicles between ultrasound and histology 1 to 1, it was sufficient to trace fascicle groupings from a point of known functional organization at the nodose ganglia to their locations within the surgical window at stimulating electrode placement. Naïve volunteers were able place an electrode proximal to the sensory afferent grouping of fascicles and away from the motor nerve efferent grouping of fascicles in each subject (n = 3).Conclusion: The surgical pocket itself provides a unique opportunity to obtain higher resolution ultrasound images of neural targets responsible for intended therapeutic effect and limiting off-target effects. We demonstrate the increase in resolution is sufficient to aid patient-specific electrode placement to optimize outcomes. This simple technique could be easily adopted for multiple neuromodulation targets to better understand how patient specific anatomy impacts functional outcomes.

Post-Mastectomy Surgical Pocket Irrigation With Triple Antibiotic Solution vs Chlorhexidine Gluconate: A Randomized Controlled Trial Assessing Surgical Site Infections in Immediate Tissue Expander Breast Reconstruction.

Post-mastectomy pocket irrigation solution choice is debated and primarily surgeon dependent. We compare triple antibiotic solution (TAS) with 0.05% chlorhexidine gluconate (CHG). The purpose of this study was to determine surgical site infection (SSI) rates after utilizing TAS vs CHG for breast pocket irrigation in immediate tissue expander (TE) breast reconstruction. A prospective, blinded, randomized controlled trial was performed in patients (18-81 years old) who underwent bilateral mastectomy with TE reconstruction. In each patient, 1 mastectomy pocket was randomized to TAS and the other to CHG. Both the TE and the pocket were irrigated in the respective solution. The primary outcome was the incidence of SSI. Secondary outcomes were rates of mastectomy flap necrosis, hematoma, and seroma. A total of 88 patients who underwent bilateral immediate breast reconstruction were enrolled. Demographic and operative characteristics were equivalent because each patient served as their own control. Between the TAS and CHG groups, the incidence of SSI did not differ (5 [4.5%] vs 7 [8.0%], P = 0.35), including minor infections (2 [2.3%] vs 1 [1.1%], P = 0.56), major infections (2 [2.3%] vs 6 [6.8%], P = 0.15), and those resulting in explantation (2 [2.3%] vs 5 [4.5%], P = 0.25). Necrosis, hematoma, or seroma formation also did not differ. No patients who developed SSI received radiation. This study does not demonstrate a statistically significant difference in SSI between TAS and CHG irrigation, though TAS approached statistical significance for lower rates of infectious complications.

The Effectiveness of Diode Laser Therapy With Scaling/Root Planing in Treating Periodontitis

Background: The effectiveness of scaling/root planing (SRP) plus 1064 wavelength diode laser therapy was compared to scaling/root planing only in treating moderate-severe (stages II–III) chronic periodontitis.Methods: Twenty-two subjects meeting all inclusion/exclusion criteria completed the study. Subjects had at least one experimental (SRP+LASER) and one control (SRP-ONLY) site randomly selected. Pre- and post-treatment clinical crown lengths (CCL), probing depths (PD) and bleeding on probing (BOP) were recorded by an examiner blinded to treatment. Bone levels were evaluated pre- and post-treatment using cone beam computed tomography.Results: Repeated measures ANOVA and t-tests were used for analysis. There were no statistically significant differences (p > 0.05) in pretreatment CCL, PD, BOP and interproximal bone height between treatment groups. In post-treatment, there were no statistically significant differences in mean changes between treatment groups (p > 0.05) for CCL, PD and BOP except for bone fill, which significantly increased for the SRP+LASER group (p = 0.002) compared to the SRP-ONLY group.Conclusions and practical implications: The adjunct use of a 1064 wavelength diode laser with definitive SRP therapy was significantly more effective (p = 0.002) than SRP alone evidenced by an increase in post-treatment bone fill. Both therapies reduced PD and BOP with minimal effect on CCL. Adjunct laser therapy may be another useful tool in the clinician’s armamentarium for managing periodontitis. Further scientific research is warranted, such as a larger scale study, greater long-term follow-up and the addition of another study arm: a comparison to surgical pocket reduction therapy.

Abstract 6247: Drug delivery with real time customizable micro-scaled continuous liquid interface printed 3D devices

Abstract Background: Surgery is a key treatment for cancer. However, local recurrence after surgery is common and can lead to significant morbidity and mortality. Current strategies to prevent recurrence include intraoperative radiation or systemic chemotherapy. We hypothesize that local chemotherapy delivery can prevent recurrence while reducing toxicity. To accomplish this, we propose to engineer 3D printed devices that can deliver chemotherapy in a localized and prolonged fashion. Methods: Paclitaxel and a cisplatin prodrug were dissolved into a liquid resin mixture of PEG550-DMA and HEMA. Custom 3D patches were printed on a Carbon 3D continuous liquid interface printer with microneedles protruding from one side of a flat surface substrate. A non-drug loaded flat backing was also printed from the same resin, and adhered to back side of the microneedle patch. Tumor growth recurrence inhibition post surgical resection was assessed in NU/NU mice in both 344SQ/Luc and A431 tumor models. Tumors were inoculated subcutaneously (106 344SQ/Luc, 5 × 105 A431) and allowed to grow until they reached 5-7mm in length. Tumors were then surgically resected and mice were either given an IV drug treatment, or had a 3D printed patch implanted in the surgical pocket. Tumor recurrence was evaluated with both luciferase bioluminescence imaging and physical measurement of tumor size. Toxicity parameters were analyzed with enzyme and CBC tests. Results: All drug loaded patches showed significant tumor growth inhibition compared to their corresponding IV drug treatment groups. While single drug loaded patches were significant in their inhibition of tumor growth compared to IV delivery of the same drug, dual drug loaded patches showed the most significant tumor inhibition compared to either single IV drug treatment or a dual IV drug treatment. There were no significant differences in measured toxicity parameters between groups. Conclusions: Our data demonstrated that local drug delivery through a customizable 3D continuous liquid interface printed drug loaded patch can improve tumor growth recurrence inhibition post surgical resection. Citation Format: C. Tilden Hagan, Cameron J. Bloomquist, Joseph M. DeSimone, Andrew Z. Wang. Drug delivery with real time customizable micro-scaled continuous liquid interface printed 3D devices [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6247.

An easy and cheap surgical pocket case for draining blood when performing scalp surgery

Skin cancers are increasing in their incidence worldwide. The scalp is a frequent site for cutaneous carcinoma, both basal cell and squamous cell. Scalp carcinomas usually bring difficulties in surgical management owing to the high bleeding risk and the uncomfortable position for the surgeon. In particular, during the surgical excision such lesions tend to bleed because of the high vascular support of the scalp, and this can negatively affect surgical management.

Microengineered biosynthesized cellulose as anti-fibrotic in vivo protection for cardiac implantable electronic devices

Upon cardiac implantable electronic device (CIED) exchange, upgrade, or revision surgery patients are exposed to a considerable risk of adverse events. The presence of firm fibrotic tissue endangers these procedures. Leads can be damaged in the attempt of freeing them from fibrotic tissue. Hematoma can form as result of capsulectomy, pocket debridement and leads dissection. Due to the increasing number of CIED exchange, upgrade and revision surgeries, the incidence of related complications is expected to rise in the near future.The aim of the study was to evaluate the feasibility, safety, and performance of a rationally micro-engineered non-resorbable biosynthesized cellulose (BC) membrane as conformal wrapping protection around CIED implants. Protective membranes were generated by means of a recently established method to transfer on-demand microscale geometries onto the surface of BC. A chronic minipig animal model was selected to investigate the performance of the BC anti-fibrotic protection, directly measured as reduction of fibrotic tissue formation. Sixteen (n = 16) animals received each one BC coated pacemaker (PMC) and one native pacemaker (BI) at equivalent anatomical sites. BC protective layers were juxtaposed around pacemakers through a fast and well-repeatable procedure. Explants were performed at 3 and 12 months after implantation. Endpoint analysis showed that the BC protective layers were 100% integer, with no sign of chemical or mechanical degradation and appeared as a thin layer of white-tan material, adherent to the surrounding thin fibrous capsule, from which it could be peeled off by gently pulling with forceps. The protective effect of micro-engineered BC yielded an average thickness reduction of 66% of the fibrotic tissue thickness generated around PMC, as compared to that measured around the naked counterpart (i.e. the BI). When protected by in BC, both the generator and the proximal parts of the leads were completely free from fibrotic tissue. The insertion of an anti-adhesive, non-resorbable and well-tolerated BC interface between the implant and the surrounding tissue in the surgical pocket significantly reduced the formation of fibrotic tissue, ensuring an easy access to the device pocket, and thus creating the conditions for simplified CIED revision surgeries.

Evaluation of antibacterial efficacy and healing with cyanoacrylate tissue adhesive after periodontal flap surgery

Surgical pocket therapy entails raising a mucoperiosteal flap in order to carry out effective debridement so as to eliminate periodontal pockets and result in a healthy periodontium. Braided silk is the most commonly used suture material following periodontal flap surgery. Cyanoacrylate tissue adhesives are slowly gaining popularity as wound closure agents. OBJECTIVES: To evaluate the antibacterial and healing properties of cyanoacrylate tissue adhesives following periodontal flap surgery. METHODS: Patients undergoing full mouth periodontal flap surgery were randomly selected for placement of cyanoacrylates or silk sutures using split mouth study design. Wound healing was evaluated at 1 week using Early Wound Healing Index. Supragingival pooled plaque samples were collected for analysis of total bacterial count at 1week follow up using lawn cultures in blood agar. Pain and burning sensation with cyanoacrylates during and post surgery was recorded using a questionnaire. RESULTS: Silk sutures showed improved wound healing when compared with cyanoacrylates. However, use of cyanoacrylates resulted in reduced bacterial colony counts thereby exhibiting antibacterial properties. Enhanced patient compliance was noted with cyanoacrylate tissue adhesives. SIGNIFICANCE: Cyanoacrylates can be used as an alternative to silk sutures for periodontal wound closure. KEY WORDS: Cyanoacrylate tissue adhesive, silk sutures, antibacterial efficacy, wound healing

Abstract: XPAND Australia: A Multi-Center Evaluation of the Aeroform Patient Controlled Tissue Expander for Breast Reconstruction

OBJECTIVE: A multi-center, prospective evaluation of the AeroForm Tissue Expander was performed to validate bench testing results following a device modification made to decrease the permeation and gradual loss of volume observed in earlier versions of the device. BACKGROUND: Previously reported results for the AeroForm Tissue Expander have demonstrated that the device can be used as effectively and safely as saline expanders to prepare the surgical pocket for breast implant placement following mastectomy. Modifications made to the device include a new material to form the inner liner which is designed to contain CO2 gas inside the expander. The permeation rate for the current device is improved to 0.3-0.4cc/day compared to previous versions which had a permeation rate of 2-4cc/day. The higher permeation rate in the previous version was observed clinically as a gradual loss of volume over time, particularly when implanted for > 6-months. These measurements were obtained via bench testing and this post-marketing study was undertaken to validate the results in-vivo. METHODS: Thirty (30) women were implanted with 50 AeroForm expanders; 20 bilateral, 10 unilateral reconstructions. Patients were followed prospectively from the time of implant, during the expansion process through the first post-operative visit after the exchange procedure. Success was measured based upon successful exchange to implant, days to complete the expansion process and the total length of time the expanders were implanted. Secondary endpoints measured were patient and physician satisfaction with the expansion process and the results of expansion. RESULTS: Twenty-six (26/30) patients completed their exchange with 4 patients awaiting an exchange date. Data is analyzed by breast with the primary endpoint defined as successful exchange to standard breast implant, precluding non-device related failures (100%). The median number of implant days is 93 with a range of 56–274 days. There have been no reports of gradual loss of volume over time or deflation. CONCLUSION: Results of the XPAND Australia post-marketing study confirm bench testing results which demonstrated an improved permeation rate of 0.4cc per day. The expander is labeled as a temporary implant (< 6-month implantation) but can be used successfully in patients undergoing chemotherapy and/or radiation who require longer implantation.

Surgical Breast Pocket Irrigation With Hypochlorous Acid (HOCl): An In Vivo Evaluation of Pocket Protein Content and Potential HOCl Antimicrobial Capacity.

Hypochlorous acid (HOCl) demonstrates rapid and broad antimicrobial activity against planktonic and biofilm phenotype bacteria in vitro. To identify the protein content present in breast pockets in vivo and calculate the estimated active concentration of HOCl, (PhaseOne, Integrated Healing Technologies, Franklin, TN) following HOCl-protein interactions. Fluid samples were collected prior to implant insertion in 18 consecutive patients, representing 36 pocket samples, with all cases being bilateral primary breast augmentations. Samples were evaluated by an independent CLIA approved laboratory for albumin and total protein concentration in g/dL. Results were compared to HOCl solution concentration and protein binding potential to determine availability of free HOCl. The mean tissue sample concentration (right and left breast) was 31.6 mg/dL which translates to 0.0001 mmol per 20 cc of interstitial fluid. Mean total protein levels (right and left breast) were 62.3 mg/dL or 0.000187 mmol per 20 cc interstitial fluid. Based upon potential stoichiometric neutralization of HOCl by proteins in either a 1:1 or 3:1 ratio, using 115 cc of HOCl solution (per breast) at a concentration of 250 ppm/mL or 0.025% HOCl or = 0.48 mmol HOCl/dL, there would be 2950 times the amount of active HOCl at a 1:1 reaction ratio, or 983 times more HOCl assuming a 3:1 reaction ratio. Based on the range of identified levels of protein in individual surgical pockets in the study, there is an estimated 242 to 12,500 times more HOCl molecules than protein at a 3:1 molar ratio of binding or reactive protein. n estimated range of 983-2950 times more HOCl molecules are present during irrigation with 230 cc of PhaseOne® (115 cc for each breast) than available protein. This supports the antimicrobial and anti-biofilm activity as described in previous in vitro studies when using PhaseOne® as part of pocket irrigation.

Sodium Mercaptoethane Sulfonate Reduces Collagenolytic Degradation and Synergistically Enhances Antimicrobial Durability in an Antibiotic-Loaded Biopolymer Film for Prevention of Surgical-Site Infections.

Implant-associated surgical-site infections can have significant clinical consequences. Previously we reported a method for prophylactically disinfecting implant surfaces in surgical pockets, where an antibiotic solution containing minocycline (M) and rifampin (R) was applied as a solid film in a crosslinked biopolymer matrix that partially liquefied in situ to provide extended prophylaxis. Here we studied the effect of adding sodium 2-mercaptoethane sulfonate (MeSNA) on durability of prophylaxis in an in vitro model of implant-associated surgical-site infection. Adding MeSNA to the M/R biopolymer, antimicrobial film extended the duration for which biofilm formation by multidrug-resistant Pseudomonas aeruginosa (MDR-PA) was prevented on silicone surfaces in the model. M/R films with and without MeSNA were effective in preventing colonization by methicillin-resistant Staphylococcus aureus. Independent experiments revealed that MeSNA directly inhibited proteolytic digestion of the biopolymer film and synergistically enhanced antimicrobial potency of M/R against MDR-PA. Incubation of the MeSNA containing films with L929 fibroblasts revealed no impairment of cellular metabolic activity or viability.