Technical considerations for isolated limb perfusion: A consensus paper.

BACKGROUND: Isolated limb perfusion (ILP) is a well-established surgical procedure for the administration of high dose chemotherapy to a limb for the treatment of advanced extremity malignancy. Although the technique of ILP was first described over 60 years ago, ILP is utilised in relatively few specialist centres, co-located with tertiary or quaternary cancer centres. The combination of high dose cytotoxic chemotherapy and the cytokine tumour necrosis factor alpha (TNFα), mandates leakage monitoring to prevent potentially serious systemic toxicity. Since the procedure is performed at relatively few specialist centres, an ILP working group was formed with the aim of producing technical consensus guidelines for the procedure to streamline practice and to provide guidance for new centres commencing the technique. METHODS: Between October 2021 and October 2023 a series of face to face online and hybrid meetings were held in which a modified Delphi process was used to develop a unified consensus document. After each meeting the document was modified and recirculated and then rediscussed at subsequent meeting until a greater than 90% consensus was achieved in all recommendations. RESULTS: The completed consensus document comprised 23 topics in which greater than 90% consensus was achieved, with 83% of recommendations having 100% consensus across all members of the working group. The consensus recommendations covered all areas of the surgical procedure including pre-operative assessment, drug dosing and administration, perfusion parameters, hyperthermia, leakage monitoring and theatre logistics, practical surgical strategies and also post-operative care, response evaluation and staff training. CONCLUSION: We present the first joint expert-based consensus statement with respect to the technical aspects of ILP that can serve as a reference point for both existing and new centres in providing ILP.

Comparison of Different Thawing Protocols in Human Cryopreserved Venous Grafts.

BACKGROUND: The aim of our study was to assess the impact of different thawing protocols on morphological changes arising in cryopreserved human saphenous vein grafts. METHODS: The study was performed in 12 saphenous vein grafts harvested in brain death donors. Storage in the vapor phase of liquid nitrogen for 3 or 5 years followed. Two thawing protocols were tested: slow thawing in a refrigerator at temperature +4°C for 2 hr and rapid thawing-in a water bath at +37°C. Grafts were processed for scanning electron microscopy. Comparisons of continuous parameters under study between experimental groups were performed using the t-test (age, cold ischemia time, exposure to cryoprotectant, time of storage, total thawing time, mean thawing rate, morphology scoring of thawed HSVG) and the median test (HSVG length). Categorical parameters (sex and blood group) were formally tested using the chi-square test. RESULTS: All samples were evaluated according to morphological changes and scored in terms of morphologically intact endothelium, confluent endothelium with structural inhomogeneity, disruption of the intercellular contacts, separation of the endothelial cells, complete loss of the endothelium, and damage of the subendothelial layers. There is no statistically significant difference between the sample sets at the significance level of 0.05. There was no association with donors' age, sex, and time of storage. CONCLUSIONS: Human cryopreserved saphenous vein grafts in our experimental work showed no difference in terms of structural deterioration of the endothelial surface and basal membrane depending on different thawing protocols used.

In Vivo Evaluation of Short-Term Performance of New Three-Layer Collagen-Based Vascular Graft Designed for Low-Flow Peripheral Vascular Reconstructions.

AIM: The aim of this study was to evaluate short-term patency of the new prosthetic graft and its structural changes after explantation. METHODS: The study team developed a three-layer conduit composed of a scaffold made from polyester coated with collagen from the inner and outer side with an internal diameter of 6 mm. The conduit was implanted as a bilateral bypass to the carotid artery in 7 sheep and stenosis was created in selected animals. After a period of 161 days, the explants were evaluated as gross and microscopic specimens. RESULTS: The initial flow rate (median ± IQR) in grafts with and without artificial stenosis was 120 ± 79 ml/min and 255 ± 255 ml/min, respectively. Graft occlusion occurred after 99 days in one of 13 conduits (patency rate: 92%). Wall-adherent thrombi occurred only in sharp curvatures in two grafts. Microscopic evaluation showed good engraftment and preserved structure in seven conduits; inflammatory changes with foci of bleeding, necrosis, and disintegration in four conduits; and narrowing of the graft due to thickening of the wall with multifocal separation of the outer layer in two conduits. CONCLUSIONS: This study demonstrates good short-term patency rates of a newly designed three-layer vascular graft even in low-flow conditions in a sheep model.

Differential impact on acute kidney injury incidence between on- and off pump coronary artery bypass grafting in octogenarians.

INTRODUCTION: Acute kidney injury (AKI) following surgical myocardial revascularization is associated with high mortality and morbidity. The aim of this study was to evaluate the risk of acute kidney injury in a population of very old patients following different surgical techniques. PATIENTS AND METHODS: A retrospective study of 310 consecutive patients aged 78 to 93 years, mean 80.5±2.2, who underwent surgery at one cardiac surgery centre. Based on the surgical technique used the patients were divided into: Group I. CABG (n=134) - surgical myocardial revascularization using extracorporeal circulation and arterial and venous grafts. Group II. OPCABG (n=55) - surgical revascularization without extracorporeal circulation but using arterial and venous grafts. Group III. NOTOUCH (n=121) - no handling with the ascending aorta was performed at all. RESULTS: A statistically insignificant renoprotective trend was found in patients who underwent surgery without extracorporeal circulation regardless of technique. Comparing groups II and III vs. group I, a significantly poorer renal functioning (median difference in creatinine was 10.0 (32.9) vs 17.5 (35.0), P=0.05) was shown for patients in group I. CONCLUSION: Surgical myocardial revascularization without extracorporeal circulation in very old patients is safe. The results of this study show a renoprotective trend.

Early pericardial valve deterioration as a result of adhesions with native mitral valve.

We report an unusual case of early pericardial tissue valve prosthesis deterioration that required replacement. Four years after mitral valve replacement, 1 of the 3 leaflets of the valve was thickened and retracted in a fixed open position, which resulted in severe mitral insufficiency. The cause of this was adhesion of the leaflet and the patient's own retained posterior mitral valve leaflet. The finding was confirmed at operation and by histologic examination.

Prediction of compartment syndrome based on analysis of biochemical parameters.

BACKGROUND: The possibility of predicting severe compartment syndrome using simple biochemical parameters was evaluated in a single-center study of 55 patients who presented with acute femoral embolism and who were treated with open surgical embolectomy. METHODS: Parameters related to tissue damage and oxidative metabolism (i.e., lactate, bilirubin, myoglobin, uric acid, glucose, and fibrinogen) were monitored in ipsilateral femoral vein blood. RESULTS: Several statistically significant predictors of relevant compartment syndrome after surgical reperfusion were found, including lactate, uric acid, transcutaneous oxygen pressure, bilirubin, intrafascial pressure, and serum myoglobin. Glycemia and serum albumin did not significantly change over time. CONCLUSIONS: The lactate concentration in femoral vein blood sampled during surgical embolectomy can be used for the stratification of additional postoperative risk of clinically significant compartment syndrome complicating reperfusion after acute embolism of the femoral artery.

Surgical extirpation of glomus tumor from rare localization on the upper extremity.

Objective. To report on a very rare case of a glomus tumor manifested on the upper arm in a healthy young male patient. Case Presentation and Intervention. A 22-year-old male patient presented with bluish multifocal venous malformation on the left upper arm and was admitted for venous malformation excision. Pain, discomfort, and upper arm paraesthesia had been present for almost 6 years. Ultrasonography revealed septet tumor without blood flow in the subcutaneous region of anterior aspect of the upper arm. A multifocal venous malformation approximately 5-10 mm in diameter was excised. Histological examination showed dilated vascular area with proliferated glomus cells with round nucleus in the wall of dilated vascular structures. Based on histological examination, the final diagnosis was made as "glomangioma." Conclusion. Histological examination is the only method that can establish final diagnosis. Currently, the only available treatment for this type of tumor is surgical excision.

Cardiogenic shock in patient with posterior postinfarction septal rupture--successful treatment with extracorporeal membrane oxygenation (ECMO) as a ventricular assist device.

We present the case of a 62-year-old female patient admitted to our center for cardiogenic shock due to large inferior myocardial infarct. Echocardiography revealed dysfunction of left ventricle, dilation of right ventricle, mitral valve insufficiency, and a large posterior ventricular septal defect (VSD). Coronary angiography showed occlusion of the right coronary artery. An attempt of percutaneous coronary intervention (PCI) of right coronary and posterior descending artery was not successful due to old thrombi. Despite inotropes and intraaortic balloon pump (IABP) there was severe hemodynamic instability. Therefore, we commenced veno-arterial extracorporeal membrane oxygenation (ECMO) as a ventricular assist device (VAD). Immediately we obtained the stabilization of the patient and the improvement of the clinical conditions. The third day after implantation, the closure of the defect, mitral valve plasty, and bypass to posterior descending artery were performed. The patient was discharged from the hospital 59 days after the operation. Six months after the operation, the patient was in good condition.

Robot-assisted aortoiliac reconstruction: A review of 30 cases.

OBJECTIVE: The feasibility of laparoscopic aortic surgery with robotic assistance has been sufficiently demonstrated. Reported is the clinical experience of robot-assisted aortoiliac reconstruction for occlusive disease and aneurysm performed using the da Vinci system. METHODS: Between November 2005 and June 2006, 30 robot-assisted laparoscopic aortoiliac procedures were performed. Twenty-seven patients were prospectively evaluated for occlusive disease, two patients for abdominal aortic aneurysm, and one for common iliac artery aneurysm. Dissections of the aorta and iliac arteries were performed laparoscopically using a transperitoneal direct approach technique, a modification of the Stádler method. The robotic system was used to construct anastomoses, to perform thromboendarterectomies and, in most of the cases, for posterior peritoneal suturing. RESULTS: Robot-assisted procedures were successfully performed in all patients. The robot was used to perform both the abdominal aortic and common iliac artery aneurysm anastomoses, the aortoiliac reconstruction with patch, and to complete the central, end-to-side anastomosis in another operation. Median operating time was 236 minutes (range, 180 to 360 minutes), with a median clamp time of 54 minutes (range, 40 to 120 minutes). Operative time is defined as the time elapsed from the initial incision to final skin closure. Median anastomosis time was 27 minutes (range, 20 to 60 minutes), and median blood loss was 320 mL (range, 100 to 1500 mL). No conversion was necessary, 30-day survival was 100%, median intensive care unit stay was 1.8 days, and median hospital stay was 5.3 days. A regular oral diet was resumed after a mean time of 2.5 days. CONCLUSION: Robot-assisted laparoscopic surgery is a feasible technique for aortoiliac surgery. The da Vinci robotic system facilitated the creation of the aortic anastomosis and shortened aortic clamp time in comparison with our laparoscopic techniques.

Diagnosis of vascular prosthesis infection with FDG-PET/CT.

Fluorodeoxyglucose positron emission tomography (FDG-PET) is on the verge of becoming an established imaging tool in the fields of clinical oncology, cardiology, and neurology. Because of the high glucose uptake of inflammatory cells, FDG scanning is an appropriate tool for use in tracing suspected inflammation or to evaluate infection. PET, although highly sensitive, often lacks the ability to define the precise anatomic location of abnormal FDG accumulation. The new PET/computed tomography (CT) technology provides precise registration of metabolic and structural imaging data in a single session. We report positive FDG-PET/CT findings in an infected vascular prosthesis 6 months after grafting. Our experience and a few available case reports support the hypothesis that FDG-PET/CT may have a promising role in future noninvasive diagnosis of infected vascular grafts.