Ultrasonographic analysis of palatal donor site healing accelerated with platelet-rich fibrin following subepithelial connective tissue harvesting.

OBJECTIVE: Platelet-rich fibrin (PRF) contains a variety of growth factors and bioactive molecules that play crucial roles in wound healing and angiogenesis. We aimed to evaluate the effects of PRF on tissue thickness and vascularization of the palatal donor site by ultrasound (USG) following subepithelial connective tissue harvesting. METHODOLOGY: A subepithelial connective tissue graft was harvested from the palatal region with a single incision for root coverage in 20 systemically healthy patients. In the test group (n = 10), the PRF membrane was placed at the donor site, whereas no material was applied in the control group (n=10). Palatal tissue thickness (PTT) and pulsatility index (PI) were evaluated by USG at baseline and on the 3rd, 7th, 14th, 30th, and 90th days after surgery. The early healing index (EHI) was used to evaluate donor site healing for 30 days. RESULTS: PTT was significantly higher in the PRF group on the 3rd and 14th days after surgery when compared to the controls. In the PRF-treated group, PI levels were significantly higher than in the controls, especially on the 14th day. PTT increased significantly 90 days after surgery compared to the test group baseline, but controls showed a significant decrease. The PRF group showed statistically significant improvements in EHI scores compared to controls on days 3, 7, and 14. This study found a negative correlation between PI values and EHI scores on postoperative days three and seven in the test group. CONCLUSION: USG is a non-invasive, objective method to radiographically evaluate the regenerative effects of PRF on palatal wound healing after soft tissue harvesting. To overcome graft inadequacy in reharvesting procedures, PRF application may enhance clinical success and reduce possible complications by increasing tissue thickness and revascularization in the donor area.

Cytokines Removal During Ex-Vivo Lung Perfusion: Initial Clinical Experience.

Ex Vivo Lung Perfusion (EVLP) can be potentially used to manipulate organs and to achieve a proper reconditioning process. During EVLP pro-inflammatory cytokines have been shown to accumulate in perfusate over time and their production is correlated with poor outcomes of the graft. Aim of the present study is to investigate the feasibility and safety of cytokine adsorption during EVLP. From July 2011 to March 2020, 54 EVLP procedures have been carried out, 21 grafts treated with an adsorption system and 33 without. Comparing the grafts perfused during EVLP with or without cytokine adsorption, the use of a filter significantly decreased the levels of IL10 and GCSFat the end of the procedure. Among the 38 transplanted patients, the adsorption group experienced a significant decreased IL6, IL10, MCP1 and GCSF concentrations and deltas compared to the no-adsorption group, with a lower in-hospital mortality (p = 0.03) and 1-year death rate (p = 0.01). This interventional study is the first human experience suggesting the safety and efficacy of a porous polymer beads adsorption device in reducing the level of inflammatory mediators during EVLP. Clinical impact of cytokines reduction during EVLP must be evaluated in further studies.

Expandable Sendai-Virus-Reprogrammed Human iPSC-Neuronal Precursors: In Vivo Post-Grafting Safety Characterization in Rats and Adult Pig.

One of the challenges in clinical translation of cell-replacement therapies is the definition of optimal cell generation and storage/recovery protocols which would permit a rapid preparation of cell-treatment products for patient administration. Besides, the availability of injection devices that are simple to use is critical for potential future dissemination of any spinally targeted cell-replacement therapy into general medical practice. Here, we compared the engraftment properties of established human-induced pluripotent stem cells (hiPSCs)-derived neural precursor cell (NPCs) line once cells were harvested fresh from the cell culture or previously frozen and then grafted into striata or spinal cord of the immunodeficient rat. A newly developed human spinal injection device equipped with a spinal cord pulsation-cancelation magnetic needle was also tested for its safety in an adult immunosuppressed pig. Previously frozen NPCs showed similar post-grafting survival and differentiation profile as was seen for freshly harvested cells. Testing of human injection device showed acceptable safety with no detectable surgical procedure or spinal NPCs injection-related side effects.

Extracción renal en donante cadáver: revisión sistemática de la técnica quirúrgica / Deceased donor kidney procurement: systematic review of the surgical technique

Introducción El proceso de extracción renal debe ser una técnica estandarizada con el fin de optimizar las unidades renales para su posterior implante. Objetivos Revisión de la literatura disponible sobre el proceso de extracción renal. Material y métodos Revisión narrativa de la evidencia disponible sobre la técnica de extracción renal en paciente cadáver tras una búsqueda de los manuscritos relevantes indexados en PubMed, EMBASE y SciELO escritos en español e inglés. Resultados La extracción renal en paciente cadáver se divide en dos grupos, tras muerte encefálica (donation after brain death [DBD]) y tras muerte cardiaca (donation after circulatory death [DCD]). La extracción renal en DBD suele acompañarse de la extracción de otros órganos abdominales y/o torácicos, lo que requiere coordinación quirúrgica multidisciplinar. Durante el proceso de extracción debe asegurarse que los pedículos vasculares renales se mantienen íntegros para su posterior implante y disminuir el tiempo de isquemia. Conclusiones La ejecución adecuada y el perfecto conocimiento de la técnica quirúrgica de extracción y de la anatomía, permite disminuir el índice de pérdidas de injertos relacionados con una incorrecta extracción (AU)

Introduction Kidney procurement procedure must be carried out following a standardized technique in order to optimize kidney grafts for their subsequent implantation. Objectives Review of the available literatura on kidney procurement procedure. Material and methods Narrative review of the available evidence on deceased donor kidney procurement technique after a search of relevant manuscripts indexed in PubMed, EMBASE and Scielo written in English and Spanish. Result Deceased donor kidney procurement can be divided into two groups, donation after brain death (DBD) and donation after circulatory death (DCD). Kidney procurement in DBD frequently includes other chest and/or abdominal organs, requiring multidisciplinary surgical coordination. During the harvesting procedure, the renal vascular pedicle must remain intact for subsequent implantation and reduced ischemia time. Conclusions Adequate execution and perfect knowledge of the technique for surgical removal and anatomy reduces the rate of graft losses associated to inadequate harvesting techniques (AU)

Laparoscopic donor nephrectomy-Technique and peri-operative outcomes in an Australian transplant center.

INTRODUCTION: Demand for donor kidneys far exceeds the availability of organs from deceased donors. Living donor kidneys are an important part of addressing this shortfall, and laparoscopic nephrectomy is an important strategy to reduce donor morbidity and increase the acceptability of living donation. AIM: To retrospectively review the intraoperative and postoperative safety, technique, and outcomes of patients undergoing donor nephrectomy at a single tertiary hospital in Sydney, Australia. METHOD: Retrospective capture and analysis of clinical, demographic, and operative data for all living donor nephrectomies performed between 2007 and 2022 at a single University Hospital in Sydney, Australia. RESULTS: Four hundred and seventy-two donor nephrectomies were performed: 471 were laparoscopic, two of which were converted from laparoscopic to open and hand-assisted nephrectomy, respectively, and one (.2%) underwent primary open nephrectomy. The mean warm ischemia time was 2.8 min (±1.3 SD, median 3 min, range 2-8 min) and the mean length of stay (LOS) was 4.1 days (±1.0 SD). The mean renal function on discharge was 103 µmol/L (±23.0 SD). Seventy-seven (16%) patients had a complication with no Clavien Dindo IV or V complications seen. Outcomes demonstrated no impact of donor age, gender, kidney side, relationship to the recipient, vascular complexity; or surgeon experience, on complication rate or LOS. CONCLUSION: Laparoscopic donor nephrectomy is a safe and effective procedure with minimal morbidity and no mortality in this series.

Tolerable degree of muscle sacrifice when harvesting a vastus lateralis or myocutaneous anterolateral thigh flap.

The myocutaneous anterolateral thigh (ALT) and vastus lateralis (VL) flaps include a large muscle mass and a sufficient vascular pedicle, and they have been used for decades to reconstruct traumatic and acquired defects of the head and neck and extremities. In spite of these benefits, musculoskeletal dysfunction was reported in nearly 1 out of 20 patients at follow-up. It is unclear whether the recently proposed muscle-sparing flap-raising approach could preserve VL muscle function and whether patients at increased risk could benefit from such an approach. Therefore, we performed a predictive dynamic gait simulation based on a biological motion model with gradual weakening of the VL during a self-selected and fast walking speed to determine the compensable degree of VL muscle reduction. Muscle force, joint angle, and joint moment were measured. Our study showed that VL muscle reduction could be compensated up to a certain degree, which could explain the observed incidence of musculoskeletal dysfunction. In elderly or fragile patients, the VL muscle should not be reduced by 50% or more, which could be achieved by muscle-sparing flap-raising of the superficial partition only. In young or athletic patients, a VL muscle reduction of 10%, which corresponds to a muscle cuff, has no relevant effect. Yet, a reduction of more than 30% leads to relevant weakening of the quadriceps. Therefore, in this patient population with the need for a large portion of muscle, alternative flaps should be considered. This study can serve as the first basis for further investigations of human locomotion after flap-raising.

Validation of a Cleanroom Compliant Sonication-Based Decellularization Technique: A New Concept in Nerve Allograft Production.

Defects of the peripheral nervous system are extremely frequent in trauma and surgeries and have high socioeconomic costs. If the direct suture of a lesion is not possible, i.e., nerve gap > 2 cm, it is necessary to use grafts. While the gold standard is the autograft, it has disadvantages related to its harvesting, with an inevitable functional deficit and further morbidity. An alternative to autografting is represented by the acellular nerve allograft (ANA), which avoids disadvantages of autograft harvesting and fresh allograft rejection. In this research, the authors intend to transfer to human nerves a novel technique, previously implemented in animal models, to decellularize nerves. The new method is based on soaking the nerve tissues in decellularizing solutions while associating ultrasounds and freeze-thaw cycles. It is performed without interrupting the sterility chain, so that the new graft may not require post-production γ-ray irradiation, which is suspected to affect the structural and functional quality of tissues. The new method is rapid, safe, and inexpensive if compared with available commercial ANAs. Histology and immunohistochemistry have been adopted to evaluate the new decellularized nerves. The study shows that the new method can be applied to human nerve samples, obtaining similar, and, sometimes better, results compared with the chosen control method, the Hudson technique.

Harvesting Composite Arterial and Vein Grafts from Deep Inferior Epigastric Artery and Vein: A Safe Five-Step Method of Preparation.

BACKGROUND: As the use of stacked flaps and options for autologous breast reconstruction increase, the level of complexity in autologous breast reconstruction has risen. Frequently, these reconstruction types present technical challenges such as vessel mismatches and short pedicle length. In this study, the authors introduce their five steps of harvesting composite deep inferior epigastric artery (DIEA) and deep inferior epigastric vein (DIEV) grafts to overcome such challenges. METHODS: The authors performed a retrospective review of patients who underwent microvascular reconstruction using DIEA/DIEV grafts from 2012 to 2020. The grafts were harvested using the five steps, as follows: step 1, a transverse, paramedian skin incision was made at the level of suprapubic crease; step 2, an oblique fasciotomy was made on the lateral rectus border; step 3, DIEA/DIEV vessels were identified and exposed past the confluence of two venae comitantes; step 4, DIEA/DIEV grafts were harvested while sparing motor nerves; and step 5, fascial closure was performed. RESULTS: A total of 40 DIEA/DIEV grafts were used in 25 patients (lumbar artery perforator flaps, n = 25; lateral thigh flaps, n = 1; superficial inferior epigastric artery flaps, n = 12; and flap salvage, n = 2) for breast reconstruction. The average time of harvest was 28 minutes, and there were two flap losses. CONCLUSIONS: In the authors' experience, DIEA/DIEV grafts can be safely harvested and used in flaps with short pedicles and small vessel size. Although the authors' experience was limited to breast reconstruction, the DIEA/DIEV grafts can be used for other types of reconstruction, especially for head and neck reconstruction.

Marking DMEK Grafts Using Bandage Contact Lens Interface Technique: Doubling the Utilization During the Acute Shortage of Donor Corneas.

PURPOSE: The purpose of this study was to describe a novel bandage contact lens (BCL) interface technique for marking the Descemet membrane endothelial keratoplasty (DMEK) graft so that a single donor cornea can be used effectively for 2 recipients during acute shortage. METHODS: This was a retrospective comparative case series. In group A, 37 eyes underwent DMEK using a graft marked by the ?BCL interface technique" that was compared with 49 conventional DMEK grafts marked through the stromal window (group B). In group A, a resized BCL with a central 3-mm hole with the concavity up was placed between the stroma and peeled-off DM. This BCL with DM was flipped for S-stamping on the DM side. Final trephination was performed on a second Teflon block. The remaining anterior lamellar tissues of group A were used on the same day for other keratoplasty procedures. Endothelial cell density (ECD) and endothelial cell loss between the 2 groups were compared after 3 and 6 months. RESULTS: The ECD at 3 months in group A (n = 35) versus group B (n = 45) was 2228 ± 270/mm2 versus 2302 ± 254/mm2 (P = 0.48), and the ECD at 6 months (n = 23 and 22) was 2058 ± 324/mm2 versus 2118 ± 260/mm2 (P = 0.72). The corresponding endothelial cell loss was 23.3% ± 6.8% versus 20.3% ± 6.1% (P = 0.18) at 3 months and 29.1% ± 8.4% versus 26.7% ± 8.0% (P = 0.34) at 6 months. Among anterior tissues of group A, 17 (45.9%) were used for deep anterior lamellar keratoplasty, 18 (48.6%) were used for larger therapeutic and tectonic grafts, and 2 were used as keratoprosthesis carriers. Donor detachment rate (8.6% vs. 8.9%) was similar in both groups without primary graft failures. CONCLUSIONS: The BCL interface technique is a simple and safe technique for stamping DMEK grafts. Anterior corneal tissues can be used for additional keratoplasties during donor shortage.

Robotic Assisted Living Donor Nephrectomies: A Safe Alternative to Laparoscopic Technique for Kidney Transplant Donation.

OBJECTIVE: To review outcomes after laparoscopic, robotic-assisted living donor nephrectomy (RLDN) in the first, and largest series reported to date. SUMMARY OF BACKGROUND DATA: Introduction of minimal invasive, laparoscopic donor nephrectomy has increased live kidney donation, paving the way for further innovation to expand the donor pool with RLDN. METHODS: Retrospective chart review of 1084 consecutive RLDNs performed between 2000 and 2017. Patient demographics, surgical data, and complications were collected. RESULTS: Six patients underwent conversion to open procedures between 2002 and 2005, whereas the remainder were successfully completed robotically. Median donor age was 35.7 (17.4) years, with a median BMI of 28.6 (7.7) kg/m2. Nephrectomies were preferentially performed on the left side (95.2%). Multiple renal arteries were present in 24.1%. Median operative time was 159 (54) minutes, warm ischemia time 180 (90) seconds, estimated blood loss 50 (32) mL, and length of stay 3 (1) days. The median follow-up was 15 (28) months. Complications were reported in 216 patients (19.9%), of which 176 patients (81.5%) were minor (Clavien-Dindo class I and II). Duration of surgery, warm ischemia time, operative blood loss, conversion, and complication rates were not associated with increase in body mass index. CONCLUSION: RLDN is a safe technique and offers a reasonable alternative to conventional laparoscopic surgery, in particular in donors with higher body mass index and multiple arteries. It offers transplant surgeons a platform to develop skills in robotic-assisted surgery needed in the more advanced setting of minimal invasive recipient operations.

Outcomes of Robotic Living Donor Right Hepatectomy From 52 Consecutive Cases: Comparison With Open and Laparoscopy-assisted Donor Hepatectomy.

OBJECTIVE: To investigate the feasibility and safety of RLDRH. SUMMARY OF BACKGROUND DATA: Data for minimally invasive living-donor right hepatectomy, especially RLDRH, from a relatively large donor cohort that have not been reported yet. METHODS: From March 2016 to March 2019, 52 liver donors underwent RLDRH. The clinical and perioperative outcomes of RLDRH were compared with those of CODRH (n = 62) and LADRH (n = 118). Donor satisfaction with cosmetic results was compared between RLDRH and LADRH using a body image questionnaire. RESULTS: Although RLDRH was associated with longer operative time (minutes) (RLDRH, 493.6; CODRH, 404.4; LADRH, 355.9; P < 0.001), mean estimated blood loss (mL) was significantly lower (RLDRH, 109.8; CODRH, 287.1; LADRH, 265.5; P = 0.001). Postoperative complication rates were similar among the 3 groups (RLDRH, 23.1%; CODRH, 35.5%; LADRH, 28.0%; P = 0.420). Regarding donor satisfaction, body image and cosmetic appearance scores were significantly higher in RLDRH than in LADRH. After propensity score matching, RLDRH showed less estimated blood loss compared to those of CODRH (RLDRH, 114.7 mL; CODRH, 318.4 mL; P < 0.001), but complication rates were similar among the three groups (P = 0.748). CONCLUSIONS: RLDRH resulted in less blood loss compared with that of CODRH and similar postoperative complication rates to CODRH and LADRH. RLDRH provided better body image and cosmetic results compared with those of LADRH. RLDRH is feasible and safe when performed by surgeons experienced with both robotic and open hepatectomy.

Minimally Invasive Donor Hepatectomy for Adult Living Donor Liver Transplantation: An International, Multi-institutional Evaluation of Safety, Efficacy and Early Outcomes.

OBJECTIVE: Evaluating the perioperative outcomes of minimally invasive (MIV) donor hepatectomy for adult live donor liver transplants in a large multi-institutional series from both Eastern and Western centers. BACKGROUND: Laparoscopic liver resection has become standard practice for minor resections in selected patients in whom it provides reduced postoperative morbidity and faster rehabilitation. Laparoscopic approaches in living donor hepatectomy for transplantation, however, remain controversial because of safety concerns. Following the recommendation of the Jury of the Morioka consensus conference to address this, a retrospective study was designed to assess the early postoperative outcomes after laparoscopic donor hepatectomy. The collective experience of 10 mature transplant teams from Eastern and Western countries was reviewed. METHODS: All centers provided data from prospectively maintained databases. Only left and right hepatectomies performed using a MIV technique were included in this study. Primary outcome was the occurrence of complications using the Clavien-Dindo graded classification and the Comprehensive Complication Index during the first 3 months. Logistic regression analysis was used to identify risk factors for complications. RESULTS: In all, 412 MIV donor hepatectomies were recorded including 164 left and 248 right hepatectomies. Surgical technique was either pure laparoscopy in 175 cases or hybrid approach in 237. Conversion into standard laparotomy was necessary in 17 donors (4.1%). None of the donors died. Also, 108 experienced 121 complications including 9.4% of severe (Clavien-Dindo 3-4) complications. Median Comprehensive Complication Index was 5.2. CONCLUSIONS: This study shows favorable early postoperative outcomes in more than 400 MIV donor hepatectomy from 10 experienced centers. These results are comparable to those of benchmarking series of open standard donor hepatectomy.

Pure Laparoscopic Versus Open Right Hepatectomy in Live Liver Donors: A Propensity Score-matched Analysis.

OBJECTIVE: The aim of the study was to present the safety and feasibility of pure laparoscopic donor right hepatectomy (PLDRH) in comparison with those of conventional donor right hepatectomy. SUMMARY BACKGROUND DATA: Although the use of PLDRH is gradually spreading worldwide, its outcomes, including the long-term outcomes in both donors and recipients, have not yet been evaluated in a large comparative study. METHODS: We retrospectively reviewed the medical records of 894 donors who underwent living donor liver transplantation between January 2010 and September 2018 at Seoul National University Hospital. We performed 1:1 propensity score matching between the PLDRH and conventional donor right hepatectomy groups. Subsequently, 198 donor-recipient pairs were included in each group. RESULTS: The total operation time (P < 0.001), time to remove the liver (P < 0.001), and warm ischemic time (P < 0.001) were longer in the PLDRH group. None of the donors required intraoperative transfusion or experienced any irreversible disabilities or mortalities. The length of postoperative hospital stay was significantly shorter in the PLDRH group (P < 0.001). The rate of complications in donors was similar between the 2 groups. Although other complication rates in recipients were, however, similar, the rates of early (P = 0.019) and late (P < 0.001) biliary complications in recipients were higher in the PLDRH group. There was no significant difference in overall survival and graft survival between the 2 groups. CONCLUSIONS: PLDRH is feasible when performed at an experienced living donor liver transplantation center. Further studies on long-term recipient outcomes including biliary complications are needed to confirm the safety.

Novel heat shock protein 90 inhibitor improves cardiac recovery in a rodent model of donation after circulatory death.

OBJECTIVE: Organ donation after circulatory death (DCD) is a potential solution for the shortage of suitable organs for transplant. Heart transplantation using DCD donors is not frequently performed due to the potential myocardial damage following warm ischemia. Heat shock protein (HSP) 90 has recently been investigated as a novel target to reduce ischemia/reperfusion injury. The objective of this study is to evaluate an innovative HSP90 inhibitor (HSP90i) as a cardioprotective agent in a model of DCD heart. METHODS: A DCD protocol was initiated in anesthetized Lewis rats by discontinuation of ventilation and confirmation of circulatory death by invasive monitoring. Following 15 minutes of warm ischemia, cardioplegia was perfused for 5 minutes at physiological pressure. DCD hearts were mounted on a Langendorff ex vivo heart perfusion system for reconditioning and functional assessment (60 minutes). HSP90i (0.01 µmol/L) or vehicle was perfused in the cardioplegia and during the first 10 minutes of ex vivo heart perfusion reperfusion. Following assessment, pro-survival pathway signaling was evaluated by western blot or polymerase chain reaction. RESULTS: Treatment with HSP90i preserved left ventricular contractility (maximum + dP/dt, 2385 ± 249 vs 1745 ± 150 mm Hg/s), relaxation (minimum -dP/dt, -1437 ± 97 vs 1125 ± 85 mm Hg/s), and developed pressure (60.7 ± 5.6 vs 43.9 ± 4.0 mm Hg), when compared with control DCD hearts (All P = .001). Treatment abrogates ischemic injury as demonstrated by a significant reduction of infarct size (2,3,5-triphenyl-tetrazolium chloride staining) of 7 ± 3% versus 19 ± 4% (P = .03), troponin T release, and mRNA expression of Bax/Bcl-2 (P < .05). CONCLUSIONS: The cardioprotective effects of HSP90i when used following circulatory death might improve transplant organ availability by expanding the use of DCD hearts.

Robotic monosegment donor hepatectomy for pediatric liver transplantation: First report.

BACKGROUND: LT for infants less than 5 kg remains a challenge with high technical complication rates, which is further compounded by large-for-size grafts requiring hyper-reduction. The benefits of MIDH especially for standard left lateral segment (LLS) resection have been unequivocally demonstrated. However, given the fine margins of error, the highly challenging technical aspects of anatomical graft reduction test the limits of safety and may not be routinely feasible with the conventional laparoscopic approach. CASE REPORT: A 14-month-old girl weighing 4.4 kg with extrahepatic biliary atresia was referred to our unit for an LT. Her mother volunteered to donate and the calculated volume of the LLS was 342 ml, with an estimated GRWR of 7.6. Given the extremely high GRWR, a segment II monosegment graft was planned. A RMDH was performed, with a final GRWR of 4. The donor and recipient were discharged on the 5th and 12th post-operative days, respectively. CONCLUSION: We present the first-ever report of an RMDH. Our report highlights the fact that robotic surgery can safely replicate a highly precise surgical operation, thereby safely pushing the limits of MIDH.

Prophylactic fasciotomy of the anterolateral thigh donor site in head and neck reconstruction.

INTRODUCTION: The free anterolateral thigh (ALT) flap is a versatile reconstructive option for head and neck defects. Donor site complications are rare but severe; with wound dehiscence, need for secondary closure, and compartment syndrome reported. OBJECTIVES: We propose prophylactic thigh fasciotomy as a surgical technique to facilitate primary closure while preventing donor site complications during ALT flap harvest. METHODS: We examined donor site wound characteristics, recipient site wound characteristics, and clinical outcomes for 24 consecutive ALT flaps performed for head and neck reconstruction from 2016 to 2018. All ALT donor sites underwent prophylactic fasciotomy. RESULTS: There were no incidents of thigh compartment syndrome or wound dehiscence of donor site; one patient underwent primary donor site skin grafting. CONCLUSION: Prophylactic thigh fasciotomy allows mobilization of soft tissue to facilitate primary tension-free closure of the ALT donor site even for free flaps with a large skin component, while reducing the possibility of compartment syndrome.