Awake Sedation With Propofol Attenuates Intraoperative Stress of Carotid Endarterectomy in Regional Anesthesia.

BACKGROUND: Carotid endarterectomy in regional anesthesia is often associated with increased perioperative stress. We assumed that carotid endarterectomy performed under awake sedation with propofol is more beneficial to prevent such stress than alprazolam premedication only. METHODS: A total of 47 consecutive patients with significant carotid artery stenosis were enrolled into this investigation and followed up for 5 years to explore vascular complications. All operations were performed under regional anesthesia. As premedication, all patients took 0.5 mg of alprazolam 30 minutes before the procedure. After randomization, 22 patients had awake sedation with target controlled propofol infusion, and the other 25 had only premedication. Cortisol plasma levels were serially analyzed: before surgery (T1), before (T2) and after release of carotid clamp (T3), and at 2 (T4) and 24 postoperative hours (T5). Alprazolam levels were also measured before and after the surgery. RESULTS: The plasma concentration of cortisol was significantly lower in the propofol sedation group at T2 (P < 0.001), T3 (P = 0.001), and T4 (P < 0.001) than in the alprazolam-only group. Alprazolam levels did not correlate with cortisol levels at any time point. A significant positive correlation was found between the clamp time and plasma cortisol level at T3 (P = 0.018), similarly between the degree of contralateral carotid stenosis and plasma cortisol level at T3 (P = 0.03). Plasma cortisol concentration 2 hours after the operation (T4) proved to be an independent predictor of carotid restenosis during the 5-year follow-up (odds ratio: 1.67, 95% confidence interval: 1.02-2.73, P = 0.04). CONCLUSIONS: An additional intraoperative propofol sedation provides better stress relief than alprazolam-only premedication during awake carotid endarterectomy.

Histological and Mechanical Assessment of Decellularized Porcine Biografts, and Its Biological Evaluation following Aortic Implantation during Mid-Term Follow-Up.

AIMS: Prosthetic graft infection frequently requires graft replacement. Among other options, a biological graft could serve as an alternative choice. Decellularization reduces tissue immunogenicity. Our aim was to determine an efficient decellularization method and to evaluate the decellularized porcine biografts' adaptability. METHODS: Four different protocols were implemented to decellularize porcine aortic segments (n = 4). Cell removal effectiveness and matrix structure preservation were histologically examined. Mechanical tests were performed. Decellularized porcine grafts were interpositioned in a porcine aorta. After a 6-month period, implanted samples were removed and evaluated using light and electron microscopy. RESULTS: Histological results showed complete removal of cells and preserved connective tissue fiber structure following decellularization, using sodium dodecyl sulfate and sodium azide. Pressure tests demonstrated similar compliance to fresh vessels. In 9 out of 10 cases, pigs survived the follow-up period. Graft rejection, intimal hyperplasia, reocclusion and/or aneurysm formation were not observed. Presence of host cells and neoendothelialization were microscopically confirmed. CONCLUSIONS: This decellularization protocol enables a cost-effective preparation of biological grafts featuring reduced immunogenicity. The implanted grafts did not degenerate during the 6-month follow-up period, the lack of graft rejection suggests acceptable immunological tolerance, while recipient cells migrate into, proliferate and differentiate, thus creating the possibility for further use as an optional vascular graft.

The role of GST polymorphism in reperfusion induced oxidative stress, inflammatory responses and clinical complications after surgical and percutaneous coronary intervention.

BACKGROUND: Patients having coronary artery disease treated by coronary bypass or PCI procedure are exposed to tissue damage because of the phenomenon called reperfusion injury. Reperfusion injury can be characterized/monitored by oxidative stress parameters, inflammatory markers and by post-operative complication rate. OBJECTIVE: Beyond the obvious factors determining its severity (affected myocardial mass, ischaemic time, collateral circulation etc.) we examined the GST enzyme group's most cardio selective member, GSTP1 and its genetic polymorphism if there is any genetically determined preventive effect on the above-mentioned parameters. MATERIALS AND METHODES: We have performed randomized prospective study in the Heart Institute of Pecs with 862 patients, treated by coronary bypass or PCI procedure. Blood samples were taken a day before, one hour, one day, one week after the operation. Leucocyte count (WBC), myeloperoxidase (MPO), thiol group (SH); Superoxide dismutase (SOD), malondialdehyde (MDA), reduced Glutathione (GSH) level was checked in different periods of time as a comparison. The onset of myocardial damage and the corresponding necro enzyme level changes were registered in the perioperative period. Our patient's GSTP1 allele pair combinations (A, B, or C) were determined by real time PCR method. RESULTS: In patients with GSTP1 AA genotype we have found significance level reaching plasma concentration rise in SOD and MDA, and drop in GSH, SH. The CKMB concentration rise in the post-operative 24 hours was significantly higher in the GSTP1 AA group. CONCLUSIONS: According to our results the AA allele combination can be considered as a risk factor. GSTP1-AA allele pair has negative effect on ischemia-reperfusion tolerance of the heart. In case of cardiovascular interventions, the study of GST enzyme polymorphisms can be an independent risk stratification factor in determining the perioperative risk in the future.

Pentoxifylline attenuates the local and systemic inflammatory response after infrarenal abdominal aortic ischemia-reperfusion.

AIMS: We studied the new anti-inflammatory effects of non-specific phosphodiesterase (PDE) inhibitor pentoxifylline (PTX) on ischaemia-reperfusion injury and postconditioning of the lower extremities. We aimed to examine the oxidative stress parameters (OSP), the inflammatory response and the changes in structure of skeletal muscle after revascularization surgery. METHODS: 50 Wistar rats in five groups underwent a 60 min infrarenal aortic cross clamping. After the ischaemia in IR+PC group ischemic postconditioning was performed, intermittent 15 seconds reperfusion, 15 seconds ischaemic periods were applied four times. The ischemic phase was followed by a 120 min of reperfusion. In IR+PTX group the animals were treated with PTX. In IR+PC+PTX group both ischemic postconditioning and PTX treatment were performed. Blood samples and biopsy from quadriceps muscle were collected. Plasma malondialdehyde, reduced glutathione, -SH-groups, TNF-alpha, IL-6 concentrations and superoxide dismutase enzyme activity were measured. RESULTS: The levels of OSP and the inflammatory proteins were significantly higher in the IR group. PTX treatment and PC could significantly decrease the levels of OSP and inflammatory proteins. When the animals were co-treated with PTX and PC the results were even better. CONCLUSIONS: Inhibition of PDE by PTX could markedly decrease the inflammatory response and moderate the ischaemia-reperfusion damages after lower limb ischemia and reperfusion. Administration of PTX could potentiate the beneficial effects of PC.

[Cerebral hyperperfusion syndrome and blood pressure control]. / Cerebralis hyperperfusiós szindróma és vérnyomáskontroll.

INTRODUCTION: Cerebral hyperperfusion syndrome is a rare, hardly known condition, which can result in serious complications either after surgical or endovascular revascularization. Recognition of the typical triad (headache, seizure, focal neurological deficit) and the prompt radiological diagnosis (sonography, computed tomography) are crucial to achieve a favourable outcome. AIM: The aim of the authors was to select the endangered group and set up an effective therapeutic protocol based their own experience in combination with relevant literature data. METHOD: From the beginning of 2010 up to now three cases with these symptoms pursuant to the criteria of cerebral hyperperfusion syndrome have been recognized by the authors. RESULTS: Each of the three patients were treated by similar principles on intensive care unit, but the applied therapy resulted in complete remission in one patient only. CONCLUSIONS: At present there is no efficient diagnostic way to screen the endangered group, hence the only opportunity for prevention is the appropriate perioperative blood pressure control. If symptoms have developed already, urgent treatment is required.

Inhibition of Glutathione S-Transferase by Ethacrynic Acid Augments Ischemia-Reperfusion Damage and Apoptosis and Attenuates the Positive Effect of Ischemic Postconditioning in a Bilateral Acute Hindlimb Ischemia Rat Model.

AIMS: We studied the effects of the inhibition of the endogene antioxidant glutathione-S-transferase (GST) by ethacrynic acid (EA) on ischemia-reperfusion (IR) injury and postconditioning (PC) in the lower extremities. We aimed to examine the oxidative stress parameters (OSP), inflammatory response and activation of proapoptotic signaling proteins (PSP) after revascularization surgery. METHODS: Sixty Wistar rats were divided into 6 groups: control, IR, PC, EA-control, IR and administration of EA (IR/EA) and PC and administration of EA (PC/EA). The IR, PC, IR/EA and PC/EA groups underwent 60 min of infrarenal aortic cross-clamping. After that, PC was performed in the PC and PC/EA groups. In 3 of the groups, the animals were treated with EA (EA-control, IR/EA and PC/EA groups) as well. The ischemia was followed by 120 min of reperfusion. Blood samples and biopsy specimens were collected from the quadriceps muscle. Plasma malondialdehyde, reduced glutathione, thiol/sulfhydryl group levels, TNF-α and IL-6 concentrations and superoxide-dismutase enzyme activity were measured. RESULTS: The levels of the OSP and the inflammatory proteins were higher in the EA-administered groups. The ratio of phosphorylated PSP was higher in the EA-administered groups and the protective effect of PC did not develop. CONCLUSIONS: Inhibition of GST by EA augmented the IR damage. GST inhibition was associated with a different activation of the mitogen-activated protein kinases and the PSP, regulating these pathways in the process of apoptosis and PC.

[Dilemmas of the reconstruction of the major pelvic artery due to infectious aortic graft complication]. / A medencei veroér helyreállításának dilemmái szeptikus aortagraft esete kapcsán.

INTRODUCTION: In the pelvic region thrombendarterectomy and bypass procedures are the most commonly performed procedures to treat peripheral artery occlusive diseases with chronic, severe circulation failure caused by atherosclerosis. Biologic and synthetic grafts can also be used in bypass surgeries. Application of synthetic grafts can acutely increase the development of the infectious graft complication and its mortality is still between 70 and 75% in pelvic processes. We describe the difficulties and dilemmas of an infectious aortobifemoral graft. CASE PRESENTATION: 58-year-old female patient with right lower limb trophic ulcer underwent a DSA examination showing a bilateral iliac occlusion and aortobifemoral bypass surgery with Dacron graft implantation was performed. Re-occlusion and infection of the graft led to an in situ silver Dacron graft replacement. Due to the one-sided re-occlusion, a femoro-femoral crossover bypass surgery applying silver graft was performed. Despite the previously described procedures the infectious process got worse and autologous deep vein reconstruction was required beside the removal of the infectious synthetic grafts at the same time. DISCUSSION: There are local and extraanatomical solutions to reduce infectious graft complication. In pelvic infections bypass surgeries using autologous deep vein can show the best results. This procedure is the trustworthiest but also the most straining technique due to the extension of surgical time and increased blood loss. The proper surgical strategy should be selected on individual bases including cardiopulmonary load ability, patient age and technical/infrastructural possibilities.

[Endovascular treatment of subclavian artery pseudoaneurysm as a delayed complication after surgery for aorto-bifemoral graft infection]. / Aortobifemoralis graft gennyedés megoldásának kései szövodményeként jelentkezo subclavia álaneurysma endovascularis kezelése.

CASE REPORT: In this article we present a relatively rare vascular surgical complication and an uncommon treatment of it. In this case we used an aorto-bifemoral bypass on a patient with Leriche syndrome. The implanted Y-graft got infected and we were forced to remove it. Having inserted the abdominal aortic graft, an axillobifemoral bypass was also applied to secure the circulation of the lower limbs. However, the graft occluded later on, and 37 months after the inital surgery a rather large pseudoaneurysm developed at the origin of the graft in the right subclavian artery. Another surgical intervention was indicated to prevent embolisation, rupture and compression. Instead of the conventional surgical method (resection, interposition) we did an endovascular procedure. We removed the false aneurysm by inserting a covered stent, using catheter technique, into the right brachial artery and therefore prevented the previously mentioned complications. DISCUSSION: This minimal invasive method is very useful for high risk patients to prevent the injury of neighbouring anatomical structures in the region as well as minimize blood loss and potential complications of long term anaesthesia when open surgery is done.

[Pathology and diagnostic opportunities of lower limb compartment syndrome]. / Az alsó végtagi compartment-syndroma kórtana és diagnosztikai lehetoségei.

BACKGROUND: The indication for the surgical treatment of lower limb compartment syndrome mostly depends on the clinical signs, which can be uncertain and often delayed, resulting in a late and insufficient intervention. AIM: In this study, the progression of compartment syndrome was monitored with the measurement of intracompartmental pressure and tissue oxygen saturation. MATERIALS AND METHODS: 16 patients (12 male and 4 female; mean age: 62,7 years) underwent acute lower limb revascularization surgery due to critical (more than 4 hour) limb ischaemia. The indications were the following: 5 iliac artery embolisms and 11 femoral artery occlusions. After revascularization, significant lower limb oedema and swelling were detected. To monitor the elevated intracompartmental pressure (ICP), KODIAG pressure meter was used. Tissue oxygen saturation (StO2) was measured with near-infrared-spectroscopy. RESULTS: In 12 cases the IPC exceeded the critical 40 mmHg. In these patients, StO2 was 50-53%, in spite of the successful re-canalisation. An urgent, semi-open fasciotomy was performed in these cases. In four patients, the clinical picture suggested compartment syndrome. However, the measured parameters did not indicate surgical intervention (ICP: 25-35 mmHg, StO2: normal). SUMMARY: In addition to the empirical guidelines, we describe an evidence based surgical intervention strategy for lower limb compartment syndrome. Our results and advised parameter intervals help the clinicians to decide between conservative and operative treatment of the disease.

[Oxidative stress and leukocyte activation after lower limb revascularization surgery]. / Alsóvégtagi revaszkularizációs mutéteket követo oxidatív stressz vizsgálata.

The authors aimed to study of oxidative stress and thrombocyte function in the perioperative interval following the revascularization surgery of lower limb. The prospective randomised study involved 10 patients whose surgical interventions were indicated by lower limb embolism, thrombosis or abdominal aorta aneurysm, and 10 healthy volunteers were also involved in the study. Peripheral blood samples were collected before, and after the surgery (2, 24 hours and one week). The maximal free radical production and lag time of the free radical production of activated leukocytes were measured, and leukocyte adhesion molecules (CD11a and CD18) signing leucocyte activation were determined as well. Endogenous antioxidant defence status, reduced glutathione (GSH), total thiol-groups (-SH), SOD activity and thrombocyte function were investigated in platelet rich plasma and in whole blood. White blood cell count and free radical production was significantly higher in patients group before surgery than in healthy group (in case of the free radical production the difference proved to be 10 times (p < 0.01)) and elevated continuously during the observation time. The CD11a and CD18 expression of the granulocytes significantly decreased right after the revascularization, but with a gradual elevation, until the 7th day they exceed the ischaemic value. GSH concentration decreased significantly 2 and 24 hours after surgery and total thiol groups (-SH) followed the same kinetics. SOD activity was significantly lower in patients group haemolysates before surgery when it was measured in healthy groups (p < 0.01) and decreased further significantly 24 hours after the surgery (p < 0.01 vs. before surgery). Suppressed thrombocyte aggregation was detected in platelet rich plasma and in whole blood during the observation excepted the one week samples, where a highly significant elevation in ADP and collagen induced aggregation were observed. Our results show a great alteration in the antioxidant-prooxidant balance and the insufficiency of platelet aggregation's inhibition after peripheral vessel closure and revascularization intervention. We suggest the monitoring of the antioxidant status and thrombocyte function of patients going to underwent surgical intervention and if it necessary the therapeutic help.