Tips and Tricks for Simple and Complex Below-the-Ankle Punctures.

CLINICAL IMPACT: When the standard endovascular crossing maneuvers have failed during CLTI recanalization procedures and the distal below-the-knee or proximal below-the-ankle retrograde access is not possible due to chronic occlusion of the vessels, mastering the more distal and complex retrograde BTA punctures may be advantageous.There are scanty reports regarding the retrograde puncture of the mid and forefoot vessels. The aim of this article is to review different tips and tricks related to these techniques to help operators to apply them in specific scenarios to eventually improve procedural success rate.

Balloon-Assisted Retrograde Puncture of Distal Vessels in Patients Unsuitable for a Conventional Transpedal Approach.

PURPOSE: To describe a novel bailout technique to approach below-the-knee chronic total occlusions after a failed bidirectional recanalization attempt using the plantar loop maneuver in patients who are poor candidates for a retrograde puncture. TECHNIQUE: After a failure of recanalization of the opposite tibial artery using the plantar loop maneuver, an assisted direct retrograde transpedal approach can be performed regardless of poor vessel caliber or even arterial occlusion. After crossing the plantar arch, a low profile angioplasty balloon is used as a landmark for the pedal puncture and to give guidance for the wire advancement from the new access. CONCLUSION: A balloon-assisted retrograde transpedal approach may be considered for below-the-knee recanalization after standard plantar loop technique failure in patients who are not candidates for conventional retrograde puncture.

Retrograde Balloon-Assisted Approach to Prevent Distal Embolization During Complex Recanalization Procedures.

PURPOSE: The purpose of the study is to describe a bailout technical strategy to prevent below-the-knee (BTK) distal embolization during procedures with increased inherent risk using universally-available "off-the-shelf" devices. TECHNIQUE: A conventional retrograde access is obtained of the BTK target vessel where embolization protection is sought. Before starting any potential proximal maneuver with an associated significant risk of distal embolization (eg, atherectomy and mechanical thrombectomy), a low-profile balloon is inserted and inflated through the distal retrograde access, so that any debris resulting from the recanalization procedure is blocked by the stagnant column of blood generated by the inflated balloon. Once the revascularization procedure has been completed, a 4F curved catheter is antegradely advanced down to the distally-inflated balloon, and in case of distal embolization the debris is aspirated in a standard fashion way. CONCLUSION: A retrograde balloon-assisted "off-the-shelf" embolic protection approach may be considered for BTK revascularization procedures where there is an inherent increased risk of distal trash, especially in the presence of distal single-vessel runoff. CLINICAL IMPACT: Distal embolization following endovascular procedures can have devastating consequences and there is a general recommendation for selective use of EPDs in high-risk-scenarios. The increased cost and low availability of the current EPD devices for BTK/BTA arteries have prohibited their widespread use. The retrograde balloon-assisted "off-the-shelf" EPD prevents distal embolization during procedures with increased risk of distal trash using inexpensive, nonspecific equipment available in any basic endovascular suite.

Ultrasound appearances and histological correlation of native arteriovenous fistula stenoses - A retrospective case series.

The pathophysiology of haemodialysis arteriovenous fistulae (AVF) stenoses is not fully understood. The aim of this study was to perform histology assessment of stenoses in native AVF and compare and correlate the findings between ultrasound and histology. Intimal medial thickness (IMT) was measured on ultrasound where there was measurable neointimal hyperplasia at the site of stenosis and percentage intimal thickening calculated. Ultrasound findings were then compared with histology analysis of AVF stenoses in nine patients. In this small sample, different sonographic appearances and histology were demonstrated. Ultrasound demonstrated stenoses with neointimal hyperplasia and those with no measurable neointimal hyperplasia. Percentage intimal thickening was between 0% and 100%. The histology of the de novo stenoses (where no previous radiological or surgical procedure was performed) demonstrated stenoses with neointimal hyperplasia, no neointimal hyperplasia and neointimal hyperplasia and fibrosis. The histology findings after percutaneous angioplasty (PTA) demonstrated stenoses with neointimal hyperplasia and fibrosis and a stenosis with an acute inflammatory reaction. The findings in this small sample demonstrated that AVF stenoses are not a uniform group as demonstrated by different sonographic and corresponding appearances at histology. Ultrasound appearances of neointimal hyperplasia appear to correlate with neointimal hyperplasia on histology. These findings warrant further investigation and may have implications for treatment strategies.

On-Site-Modified Sheath to Overcome the Undesirable Catheterization of the Profunda Femoris Artery During Antegrade Femoral Access.

Purpose: To present a simple method to avoid favored passage of a guidewire into the profunda femoris artery (PFA) after antegrade puncture of the common femoral artery. Technique: A 6-F conventional introducer sheath with a radiopaque distal marker is placed on the nurse's table with its side port orientated to the 12 o'clock position. A small (2-2.5 mm) oval fenestration is created on the superior aspect of the sheath about 3 cm from its tip with a size 11 surgical blade. The modified introducer is passed over the angled 0.035-inch guidewire into the PFA and gently retrieved until the tip marker is ~3 cm from the femoral bifurcation. The dilator is removed, and the guidewire is withdrawn to the level of the fenestration, manipulated through it, and advanced further into the superficial femoral artery under fluoroscopic guidance. Conclusion: When repeated passage of the guidewire down the PFA persists despite conventional manipulation of the wire or needle, an on-site modification of the sheath is an easy alternative approach for the catheterization of the superficial femoral artery.

Homemade Device to Facilitate Percutaneous Venous Arterialization in Patients With No-Option Critical Limb Ischemia.

PURPOSE: To describe a maneuver to facilitate percutaneous arteriovenous fistula creation during venous arterialization procedures in patients with no-option critical limb ischemia. TECHNIQUE: Following a failed arterial recanalization attempt, a balloon catheter is passed up to the tip of the guidewire. Venous access is gained distally, a 4-F sheath is antegradely passed, and a 4-mm GooseNeck snare is advanced through it. A fluoroscopic view that overlaps the snare and the inflated balloon is obtained. If the vein remains anterior with respect to the artery, a needle is inserted across the vein, passing through the snare loop and puncturing the intra-arterial balloon. A wire is inserted and placed inside the punctured balloon. The balloon is retrieved and the wire externalized through the femoral access. A catheter is advanced antegradely over this wire from the artery into the vein. If the vein remains posterior to the artery, a needle is inserted, puncturing the balloon and thereafter the vein (crossing through the snare). A wire is inserted, captured by the snare, and externalized through the vein sheath. A catheter is finally advanced over this wire from the vein into the artery. CONCLUSION: This maneuver is a simple alternative to create an arteriovenous fistula during venous arterialization procedures in patients with no-option critical limb ischemia.

A Modified Syringe Plunger Device Significantly Reduces Guidewire Threading Time Regardless of Experience Level or the Presence of Presbyopia.

PURPOSE: To evaluate the efficacy of a new guidewire threading instrument (GTI) in reducing guidewire threading times compared with the traditional freehand method. MATERIALS AND METHODS: This prospective, controlled, single-center study recruited 100 subjects (mean age 45.2±11.3 years; 43 men) and divided them into 2 groups depending on their professional background: 50 experienced medical personnel (performed or assisted in >50 catheter-based procedures) and 50 medical personnel with no experience in endovascular techniques (inexperienced group). The threading time of both groups was recorded using the conventional freehand method and with the GTI for both 0.035- and 0.014-inch platforms. Users of eyeglasses for presbyopia were tested with and without glasses. Median values are reported with the interquartile range (IQR; Q1, Q3) in parentheses. RESULTS: The mean insertion times with both the 0.035-inch and 0.014-inch guidewires in the overall study group were significantly better with the use of the GTI compared with the traditional freehand method (p<0.001). Both the experienced and the inexperienced participants improved their insertion times using the GTI with both guidewire platforms (p<0.001). The threading time with the new device was also significantly reduced (p<0.001) for both participants with presbyopia and those without. When comparing the median absolute time improvement (difference between freehand/GTI insertion times) for the 0.014-inch platform, the inexperienced group showed a greater improvement in their performance [3.52 seconds (IQR 2.76, 5.12)] compared with the experienced group [1.87 seconds (IQR 1.37, 2.66), p<0.001]. The median "absolute time improvement" was also significantly greater for the presbyopic group [5.75 seconds (IQR 3.14, 8.20)] vs the group without age-related visual impairment [2.64 seconds (IQR 1.65, 3.36), p<0.001]. CONCLUSION: This simple and inexpensive homemade device facilitates wire threading of low-profile catheters and seems to be especially helpful for trainees with no experience and presbyopic operators.

Femoropopliteal CTO Subintimal Recanalization Using a Homemade Reentry Device.

A case of a femoropopliteal recanalization procedure using a new bailout technical maneuver to aid reentry into the true lumen is described. After a failed standard reentry attempt, at the level of the vessel reconstitution in the subintimal space, the guidewire was exchanged for a GooseNeck Snare Kit. A needle was inserted across the target artery, piercing both arterial walls and passing through the snare loop. Once the needle had exited the artery, a wire was inserted and the needle withdrawn. The snare was closed, withdrawn, and the wire externalized through the femoral access. Finally, a catheter was advanced from the antegrade sheath up to the arterial reconstitution. Selective injection at the site of reentry confirmed the intraluminal position, and the procedure was successfully completed from the antegrade sheath.

Technique to Facilitate Retrograde Puncture of Mid to Upper Calf Tibial Vessels.

PURPOSE: To describe a simple maneuver to facilitate the retrograde puncture of challenging tibial vessels in the lower leg. TECHNIQUE: Because of the depth of the tibial vessels at the mid to upper calf, especially in obese or muscular patients, a 7- or 9-cm, 21-G micropuncture needle is often needed to reach the artery. However, the low profile of the needle contributes to its flexibility and therefore the tendency to bend as it progresses through the deep tissues, hindering access to the target vessel. To overcome this obstacle, a 4- to 5-cm, 18-G needle is initially placed pointing to the artery. The 21-G needle is advanced through it to the target site. This simple maneuver increases the support to the 21-G needle, preventing its bending and facilitating arterial puncture in the presence of calcified vessels. CONCLUSION: The telescoping needle technique may be considered as a bailout procedure in the retrograde tibial approach after failed attempts secondary to needle bending or calcified vessels.

Buddy Needle Technique to Facilitate Retrograde Puncture of Heavily Calcified Tibial Vessels.

PURPOSE: To describe a technical trick to overcome a prior failed retrograde puncture of the tibial vessels secondary to arterial calcification. TECHNIQUE: Following a prior failed retrograde puncture attempt, the needle is left in place next to the artery. The tip of the needle is then moved toward the artery as a lever so that the artery is fixed between the needle, the skin, and the surrounding tissues. With the artery fixed, a standard puncture procedure is performed. Alternatively, if additional support is needed, 2 micropuncture needles are inserted one on either side of the artery, crossing under the target vessel and hence trapping it between them, providing additional support and therefore enhancing the chance of successful arterial access. CONCLUSION: The buddy needle technique may be considered as an alternative procedure in a retrograde pedal/tibial approach after prior failed standard attempts in patients with heavily calcified vessels.

A new simple method of converting a retrograde femoral access to an antegrade catheterization.

Antegrade puncture is a routinely used technique of obtaining access to the common femoral artery to perform infrainguinal interventions. However, antegrade arterial access can be challenging in the presence of hostile, scarred groins, obesity, or a high common femoral artery bifurcation. A simple method of converting a retrograde femoral access to an antegrade catheterization using an inexpensive and universally available monofilament suture is presented.

Case report of mannose-binding lectin (MBL) deficiency and postoperative sepsis and coagulopathy in a patient following total pancreatectomy for chronic pancreatitis.

CONTEXT: Complement plays a central role against infection and coordinates the activity of coagulation and fibrinolysis. In this report we present a patient that underwent total pancreatectomy experienced sepsis, coagulopathy and bleeding that endangered the postoperative course. CASE REPORT: A sixty-five-year-old woman underwent total pancreatectomy for intractable pain without islet transplant, this patient was diagnosed as AP and MBL deficient from a blood test performed preoperatively. On the postoperative course she experienced severe haemorrhages and sepsis for 3 weeks postoperatively. An analysis of serial perioperative serum samples conducted which showed further depletion of the alternate and MBL complement pathway without restoration to baseline levels. CONCLUSION: This is the first reported case of alternative and mannose-binding lectin pathways depletion associated with major postoperative bleeding and sepsis following pancreatic surgery. Future research should examine the relationship between complement pathways activity and postoperative complications in order to possibly introduce it as a preoperative screening and possible replacement therapy prior to any major surgical intervention.

The development of a multiorgan ex vivo perfused model: results with the porcine liver-kidney circuit over 24 hours.

We already developed an ex vivo liver-kidney model perfused for 6 h in which the kidney acted as a homeostatic organ to improve the circuit milieu compared to liver alone. In the current study, we extended the multiorgan perfusions to 24 h to evaluate the results and eventual pitfalls manifesting with longer durations. Five livers and kidneys were harvested from female pigs and perfused over 24 h. The extracorporeal circuit included a centrifugal pump, heat exchanger, and oxygenator. The primary end point of the study was the evaluation of the organ functions as gathered from biochemical and acid-base parameters. In the combined liver-kidney circuit, the organs survived and maintained an acceptable homeostasis for different lengths of time, longer for the liver (up to 19-23 h of perfusions) than the kidney (9-13 h of perfusions). Furthermore, glucose and creatinine values decreased significantly over time (from the 5th and 9th hour of perfusion onward). The addition of a kidney to the perfusion circuit improved the biochemical environment by removing excess products from ongoing metabolic processes. The consequence is a more physiological milieu that could improve results from future experimental studies. However, it is likely that long perfusions require some nutritional support over the hours to maintain the organ's vitality and functionality throughout the experiments.

Changes in plasma and erythrocyte omega-6 and omega-3 fatty acids in response to intravenous supply of omega-3 fatty acids in patients with hepatic colorectal metastases.

BACKGROUND: Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are functionally the most important omega-3 polyunsaturated fatty acids (PUFAs). Oral supply of these fatty acids increases their levels in plasma and cell membranes, often at the expense of the omega-6 PUFAs arachidonic acid (ARA) and linoleic acid. This results in an altered pattern of lipid mediator production to one which is less pro-inflammatory. We investigated whether short term intravenous supply of omega-3 PUFAs could change the levels of EPA, DHA, ARA and linoleic acid in plasma and erythrocytes in patients with hepatic colorectal metastases. METHODS: Twenty patients were randomised to receive a 72 hour infusion of total parenteral nutrition with (treatment group) or without (control group) omega-3 PUFAs. EPA, DHA, ARA and linoleic acid were measured in plasma phosphatidylcholine (PC) and erythrocytes at several times points up to the end of infusion and 5 to 12 days (mean 9 days) after stopping the infusion. RESULTS: The treatment group showed increases in plasma PC EPA and DHA and erythrocyte EPA and decreases in plasma PC and erythrocyte linoleic acid, with effects most evident late in the infusion period. Plasma PC and erythrocyte EPA and linoleic acid all returned to baseline levels after the 5-12 day washout. Plasma PC DHA remained elevated above baseline after washout. CONCLUSIONS: Intravenous supply of omega-3 PUFAs results in a rapid increase of EPA and DHA in plasma PC and of EPA in erythrocytes. These findings suggest that infusion of omega-3 PUFAs could be used to induce a rapid effect especially in targeting inflammation.

Staging laparoscopy for hilar cholangiocarcinoma in 100 patients.

PURPOSE: Accurate preoperative radiological staging of hilar cholangiocarcinoma remains difficult, and a number of patients are found to have irresectable advanced tumours or occult metastases at exploration. Staging laparoscopy can improve the detection of irresectable disease, avoiding unnecessary laparotomy. This study examines the role of staging laparoscopy in hilar cholangiocarcinoma, with a focus on yield over different time periods and identification of preoperative factors increasing the risk of irresectable disease. METHODS: Retrospective case note review of all patients undergoing staging laparoscopy for radiologically resectable hilar cholangiocarcinoma, identified from the hepatobiliary multidisciplinary team database, was performed. RESULTS: One hundred consecutive patients underwent staging laparoscopy between 1998 and 2011. Of these, 34 patients were found to be irresectable due to metastatic disease, and 11, due to extensive local disease. Fifty patients proceeded to exploratory laparotomy following staging laparoscopy, and 36 % (18/50) of whom were found to have irresectable disease: 12 patients due to advanced local disease and 6 patients due to metastases. The overall yield of laparoscopy was 45 %, and the accuracy was 71 %. There was no significant difference in age, preoperative bilirubin, neutrophil/lymphocyte ratio, Ca19-9 levels or T stage between patients with resectable disease and with irresectable disease on laparoscopy. There was also no change in the yield of laparoscopy over time, despite advances in radiological imaging. CONCLUSION: In this series, staging laparoscopy avoided unnecessary laparotomy in 45 % of patients with radiologically resectable hilar cholangiocarcinoma. No factor was able to predict positive yield, and therefore, all patients with potentially resectable hilar cholangiocarcinoma should undergo staging laparoscopy.

Histological changes during extracorporeal perfusions of the porcine liver: implications for temporary support during acute liver failures.

Ex vivo perfused porcine livers have been used for temporary support during acute liver failure. The aim of this study was to assess both the histological changes and temporal pattern of the changes that occur during extracorporeal liver perfusions and to correlate these with factors that may influence them. Five porcine livers were harvested, preserved in cold ice and reperfused for 6 h in an extracorporeal circuit using autologous normothermic blood. Tissue biopsies were collected hourly. The Ishak score was used to quantify hepatic necrosis, and immunohistochemistry was used to evaluate apoptosis and regeneration. Liver weight, perfusion parameters, arterial blood gases and blood samples were also collected. The Ishak score peaked immediately before and 4 h after the start of reperfusion. Scattered necrosis, microvesicular steatotic vacuolization, sinusoidal dilatation and red cell extravasation were present. Anion gap acidosis was associated with the Ishak score. An inverse correlation was present between liver regeneration and necrosis, and between liver weight and regeneration. No changes were observed for apoptosis. Among the inflammatory cytokines evaluated, interleukin-6 and -8 levels increased significantly during the perfusions. Hepatic necrosis was always present during the extracorporeal perfusions, followed a definite pattern and was inversely correlated with regeneration. Apoptosis did not increase over baseline levels. The meaning of these findings and their correlation with clinical outcomes during acute hepatic failures deserve further investigation.

Impact of anticoagulation on outcomes in acute non-cirrhotic and non- malignant portal vein thrombosis: a retrospective observational study.

BACKGROUND/AIMS: No definitive evidence exists regarding the treatment of acute portal vein thrombosis (PVT). Treatment modalities that have been employed and investigated include conservative management, anticoagulation, thrombolysis and thrombectomy. This observational study examines the impact of anticoagulation on PVT. METHODOLOGY: The electronic radiology database was searched with keywords 'portal vein' and 'thrombosis'. Relevant patient notes and imaging were reviewed to collect data from those with acute PVT. The primary end point was portal vein recanalisation. Secondary outcome measures were morbidity and the development of portal hypertension and its sequelae (including variceal bleeding). Data from patients with PVT in the context of cirrhosis, malignancy or liver transplant were excluded. RESULTS: Partial or complete recanalization of the portal vein occurred in 81.8% of anticoagulated patients and 37.5% of the non-treatment group. Five patients died, 1 following an intracranial haemorrhage whilst anticoagulated and another who was not treated and developed secondary small bowel ischaemia and peritonitis. The remaining 3 died from their underlying pathology. Late complications, such as varices and ascites occurred more frequently in the patients in whom the portal vein failed to recanalize (83.3% vs. 27.3%). CONCLUSIONS: Spontaneous resolution of acute portal vein thrombosis is uncommon. Early anticoagulation results in a higher rate of recanalisation with minimal associated morbidity when compared with no treatment.

Reduction in circulating pro-angiogenic and pro-inflammatory factors is related to improved outcomes in patients with advanced pancreatic cancer treated with gemcitabine and intravenous omega-3 fish oil.

BACKGROUND: Pancreatic cancer is a rapidly progressive disease which is often only amenable to palliative treatment. Few patients respond to palliative chemotherapy, so surrogate markers indicating which patients are likely to respond to treatment are required. There is a well-established link between pro-inflammatory circulating cytokines and growth factors (CAF), and the development of neoplasia. Agents that may modulate these factors are of interest in developing potential novel therapeutic applications. METHODS: As part of a single-arm phase II trial in patients with advanced pancreatic cancer (APC) treated with gemcitabine and intravenous (i.v.) omega-3 rich lipid emulsion (n-3FA), serum samples were analysed for 14 CAF using a multiplex cytokine array. Baseline serum concentrations were correlated with overall (OS) and progression-free survival (PFS), and changes in concentration correlated with time and outcomes for CAF responders were analysed. RESULTS: Platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF) concentrations reduced significantly with treatment over time. Low baseline interleukin (IL)-6 and -8 were correlated with improved OS. PDGF responders showed a tendency towards improved OS and FGF responders a significantly improved PFS. DISCUSSION: Treatment with gemcitabine plus i.v. n-3FA may reduce concentrations of CAF which may be associated with an improved outcome. Baseline IL-6 and -8 may be surrogate markers for outcome in patients with APC treated with this regimen.