Aorto-iliac endarterectomy: Old-fashioned or re-newed method?

INTRODUCTION: Aorto-iliac occlusive disease is best treated with endovascular angioplasty/stenting or surgical bypass, depending on disease severity. Aorto-iliac endarterectomy was frequently used until the 1980s. However, it can still be performed in cases of previous failure or contraindication of standard methods. The aim was a retrospective evaluation of a single-center case series of aorto-iliac endarterectomy. METHODS: Seven patients at mean age 60±8 years (5768 years) were treated by aorto-iliac endarterectomy between 2013 and 2018. Rutherford categories of leg ischemia were 2 (moderate claudication) 3x, 3 (severe claudication) 2x, 4 (rest pain) and 5 (toe gangrene). The reasons for endarterectomy approach were: late in-stent iliac occlusion in an oncology patient, failure or complication of previous endovascular treatment of short iliac stenosis 2×, high infection risk of prosthesis use in long iliac-femoral occlusion, and short iliac occlusions 3x. Two patients after previous organ transplant were on immunosuppression. RESULTS: Technical success rate was 100%. There was no peri-operative (30 days) death or amputation. Mean follow-up was 17 months (1.1 month3.3 year). One patient required additional tibial bypass 1 month after endarterectomy to heal foot gangrene. One patient developed symptomatic re-stenosis which was treated with iliac stenting 8 months after procedure. All patients clinically improved and recovered from leg ischemia. Two patients died of tumor with preserved limb 1.1 month and 3.1 years after procedure, respectively. Five remaining patients are asymptomatic with patent revascularization to date. CONCLUSION: Aorto-iliac endarterectomy is a vital alternative technique for revascularization in selected patients when other methods seem inappropriate. Key words: endarterectomy - peripheral arterial disease - iliac artery - abdominal aorta.

Fractionated plasma separation and adsorption significantly decreases intracranial pressure in acute liver failure: experimental study.

BACKGROUND: The aim of the study was to determine the influence of fractionated plasma separation and absorption (FPSA) on intracranial pressure (ICP) in acute liver failure (ALF). METHODS: A surgical model of ALF in pigs (35-40 kg) was used. We compared laboratory data and haemodynamic parameters from the ALF control group to the ALF group treated by Prometheus using ANOVA with repeated measures and grouping factors, by calculating the area under the curve, and by the Mann-Whitney rank test. RESULTS: Bilirubin levels differed significantly in favour of the FPSA treatment group: after 6 h 12.81 +/- 6.54 versus 29.84 +/- 9.99, after 9 h 11.94 +/- 4.14 versus 29.95 +/- 12.36 (p < 0.01) and after 12 h 13.88 +/- 6.31 versus 26.10 +/- 12.23 mmol/l (p < 0.05). ICP values differed significantly in favour of the FPSA treatment group: after 9 h 19.1 +/- 4.09 versus 24.1 +/- 2.85 (p < 0.01), after 10 h 21.9 +/- 3.63 versus 25.1 +/- 2.19, after 11 h 22.5 +/- 3.98 versus 26.3 +/- 3.50, and after 12 h 24.0 +/- 4.66 versus 29.8 +/- 5.88 mm Hg (p < 0.05). CONCLUSION: The authors demonstrated that a significant decrease in ICP was found in pigs with ALF following treatment by FPSA.

[Biological and non-biological elimination therapy of acute liver failure. Experimental study on large laboratory animal]. / Biologická a nebiologická eliminacní lécba akutního selhání jater experimentální práce na velkém laboratorním zvíreti.

BACKGROUND: Development of biological and non-biological artificial liver devices in the previous 20 years enabled effective treatment of acute liver failure (ALF) of patients waiting for liver transplantation or for spontaneous liver parenchyma regeneration. Aim of the study was the evaluation of the effectiveness of biological (BAL - bioartificial liver) and non-biological (FPSA - Fractionated plasma separation and adsorption) methods in the treatment of experimental ALF on large laboratory animal. METHODS AND RESULTS: Surgical model of ALF with liver devascularization in pigs (weight 25-40 kg) was provided following monitoring of ALF markers (AST, ALT, bilirubin, ammoniac, glycaemia, INR) including intracranial pressure (ICP). Control group included animals without treatment of ALF. Results of both experimental groups were compared and statistically worked-out with that of controls by T-test and Mann-Whitney non-parametric test by EXCEL and QUATRO. BAL group: 10 pigs (weight 30 +/- 5 kg) with ALF were treated by BAL with isolated hepatocytes. When plasma bilirubin was compared, significant differences (p < 0.05) in 6 and 9 hours interval were found favouring BAL group (18.1 vs. 13.1, 22.9 vs. 13.2 mmol/l). The value of ICP in both groups was no significant. Prometheus group: 14 pigs weight 35 kg (35 +/- 5 kg) with the identical ALF were treated by Prometheus (FPSA). Level of serum bilirubin in experimental group when compared to control group was significantly lower (p < 0.01) at 6 hour interval 12.81 +/- 6.54 vs. 29.84 +/- 9.99 at 9 hour 11.94 +/- 4.14 vs. 29.95 +/- 12.36 and at 12 hour 13.88 +/- 6.31 vs. 26.10 +/- 12.23 mmol/l. No significant difference in serum ammonia level was found. ICP was significantly different from 9 hour to 12 hour interval in favour of FPSA group (p < 0.01): 9 hour 19.1 +/- 4.09 vs. 24.1 +/- 2.85, 10 hour 21.9 +/- 3.63 vs. 25.1 +/- 2.19, 11 hour 22.5 +/- 3.98 vs. 26.3 +/- 3.50 and 12 hour 24.0 +/- 4.66 vs. 29.8 +/- 5.88 mm Hg. CONCLUSIONS: Significant improvement of bilirubin and ICP levels resulting from the treatment with fractionated plasma separation and adsorption (Prometheus) were observed in the case of experimental ALE Except the bilirubin levels, bioartificial liver provided by O. liver Performer with isolated hepatocytes did not bring any significant improvement of laboratory markers, including ICP.

[Current benefit of biological and non-biological methods in the treatment of acute liver failure]. / Soucasný význam biologických a nebiologických eliminacních metod v lécbe akutního selhání jater.

BACKGROUND: There was an active interest in development of liver assist device in the last two decades. Using these devices to bridge patients with acute hepatic failure (AHF) to ortotopic liver transplantation (OLTx) or to liver regeneration might decrease the mortality rate. Several liver support systems have been described in different stages of experimental or clinical examination. METHODS: PubMed (1986-2008) was searched using the keywords "artifitial livers", "liver support", "bioartifitial liver" and "cell transplantation". The own experience presenting by authors are the conclusions of their publications. RESULTS AND DISCUSSION: Biological liver support (BAL) uses hepatocytes can support theoretically both detoxification and biosynthesis. Experimental study confirmed significant decrease in some of AHF metabolites. Nevertheless, randomized study didn't show any improvement in patient's survival. Source of viable hepatocytes and sufficient bioreactor capacity are some of unsolved problems. Nonbiological liver support as a plasma exchange, hemodialysis, hemofiltration, albumin dialysis or adsorbent recycling systems eliminate some of toxins, but other specific liver functions can't replace. MARS and Prometheus devices have been used successfully in treatment of AHF by human. However, the absence of randomized study still lasts. These devices remove some of toxins and cytokines unselectively and are also limited by adsorber capacity. Selective plasma filtration therapy and hybrid liver support systems which combine both of management advances present the possible solution. Authors themselves confirmed by application of both methods a significant decrease of bilirubin level. Intracranial pressure declines only by use of non-biological device - Prometheus. CONCLUSION: Effective liver assist device that gains a survival approval hasn't been developed till now. In confrontation with other current used cure possibilities, BAL didn't propose the original expectations. On the other hand, the non-biological devices seem to be perspective and their contribution has been proved by prospective studies. The randomized study is still absent. Authors' experiences confirm this trend.

Hemodynamic parameters in a surgical devascularization model of fulminant hepatic failure in the minipig.

Animal models of fulminant hepatic failure (FHF) are important for studying the pathophysiology of this process and for evaluation of the efficacy of artificial and bioartificial liver support systems. In experiments, hemodynamic parameters were monitored in a group of minipigs with FHF induced by surgical devascularization, and compared with those in a control group. During the experiment, animals were analgosedated and were on mechanical lung ventilation. Crystalloid and colloidal solutions were administered and norepinephrine in continuous infusion was applied if mean arterial pressure (MAP) decreased below 60 mm Hg despite adequate intravascular volumes. An increase in heart rate, and decreases in MAP and systemic vascular resistance, compared with the baseline, occurred in the FHF group from 6 h after surgery. A comparison of FHF and control groups revealed no significant differences in systemic vascular resistance and MAP until after 12 h after surgery (systemic vascular resistance index: 953 FHF vs. 1658 controls; p < 0.05; MAP: 58.1 FHF vs. 76 controls; p < 0.05). No significant differences in CI were seen between the FHF group and controls. FHF animals survived for about 13 h after surgery, i.e. a period, which we consider long enough to test a support device. The parameters are believed to be quite adequate, as we were able to maintain satisfactory hemodynamic stability in all experimental animals with induced acute hepatic failure.

[A model of acute hepatic failure in a minipig from the surgical and anesthesia point of view]. / Model akutního selhání jater u miniprasete z hlediska chirurga a anesteziologa.

AIM: The aim of this study was to create an easily reproducible model of the acute hepatic failure (ASJ) in a minipig, which may allow to test supporting eliminating systems. The aim of this report was to describe the surgical technique with the anaesthesiological procedure and to demonstrate the experimental results on a group of the laboratory animals. METHODOLOGY: The ASJ was mocked using surgical devascularization of the liver: a ligature of the a. hepatica propria and v. portae, creating a portocaval anastomosis end-to-side. The animals were analgosedated during the experiment and were on a ventilatory support. Biochemical indicators of the hepatic failure, the ICP and the haemodynamics parameters were monitored. Hypoglycaemia with levels below 3.5 mmol and any increase of the intracranial pressure (ICP) were considered the onset of the hepatic failure. MATERIAL: 20 minipigs weighing 25-30 kg and divided in 3 groups, were included in the experiment: I--10 animals were assigned to the acute hepatic failure (ASJ) group, II--5 animals with the mock acute hepatic failure (ASJ), whose ICP was monitored in conjunction with the standard monitoring and III. 5 animals without the acute hepatic failure (ASJ)--a control group. RESULTS: We proved significant differences in the AST levels (33.44 +/- 39.96 vs. 1.56 +/- 0.50 mmol/l), the lactate levels (2.97 +/- 1.16 vs. 1.18 +/- 0.61 mmol/l), and the ammonium levels (264.3 +/- 93.05 vs. 42.5 +/- 12.98 micromol/l) in the acute hepatic failure (ASJ) group compared with the control group (p < 0.01) 6 hours after the surgery and significant changes in the glycaemia levels and the intracranial pressure (ICP) measurements 4 hours after the surgical procedure. Increase in the pulse frequency, the blood pressure, decrease of the mean arterial pressure (MAP) and decrease in the systemic venous resistence index (SVRI) in the acute hepatic failure (ASJ) group was recorded 6 hours after the procedure compared with the initial findings, with significant differences between the acute hepatic failure (ASJ groups and the control group as late as during the 12th hour following the procedure (SVRI: 953 ASJ vs. 1658 control, p - 0.05, MAP: 58.1 ASJ vs. 76 control, p - 0.05). No statistically significant differences in the heart index between the acute hepatic failure (ASJ) group and the control group were recorded. The animals with the acute hepatic failure (ASJ) survived 13 hours following the surgical procedure, on average.

Devascularization surgical model of acute liver failure in minipigs.

AIM: The study was designed to develop a readily reproducible model of acute liver failure (ALF) in the minipig, to gain an 8-hour therapeutic window to mimic, as closely as possible, acute liver failure in man. METHOD: We used reversible devascularization model of ALF in the minipig involving hepatic artery ligation and establish an end-to-side portocaval anastomosis. Standard laboratory monitoring was complemented with intracranial pressure (ICP) measurement. MATERIAL: Twenty minipigs (weight 25-30 kg) were used for the experiment. The animals were divided into 3 groups: I: 10 animals in an experimental group with ALF; II: 5 animals in an experimental group with ALF and ICP measurement, and III: 5 animals in a control group without ALF. RESULTS: Laboratory testing has shown the significant changes in levels of AST (33.44 +/- 39.96 vs. 1.56 +/- 0.50 mmol/l), lactate (2.97 +/- 1.16 vs. 1.18 +/- 0.61 mmol/l), and ammonia (264.3 +/- 93.05 vs. 42.5 +/- 12.98 mmol/l) between ALF groups and controls (p < 001) 6 h after the operative procedure, and significant changes in hypoglycemia and intracranial pressure were found 4 h after the operative procedure. The difference in Quick values (67.4 +/- 17.03 vs. 75.2 +/- 2.68) was not significant. We assume that the therapeutic window starts 4 h after the beginning of the experiment. CONCLUSION: Our devascularization model of ALF is simple and readily reproducible. The therapeutic window occurring shortly after surgery and persisting for a mean 9 h is suitable to evaluate bioartificial liver devices.