Endovascular evaluation and treatment of intrahepatic portosystemic shunts in dogs: 100 cases (2001-2011).

OBJECTIVE: To evaluate short- and long-term outcome following endovascular treatment of intrahepatic portosystemic shunts in dogs. DESIGN: Retrospective case series. ANIMALS: 100 dogs. PROCEDURES: All patients had angiographic evaluation with or without endovascular shunt attenuation. The medical records were reviewed for pertinent data, complications, outcome, and survival time. RESULTS: 95 dogs with congenital intrahepatic portosystemic shunts received 111 procedures (83% [79/95] had 1 treatment, and 17% [16/95] had > 1 treatment; 5 dogs had no treatment because of excessive portal venous pressure-central venous pressure gradients). Angiography identified 38 right, 33 left, and 19 central divisional single shunts (n = 90) and 10 complex or multiple shunts. Partial shunt attenuation was performed in 92 dogs by means of caval stent placement and insertion of thrombogenic coils within the shunt, and 3 had complete acute shunt occlusion. Major intraoperative complications (3/111 [3%]) included temporary severe portal hypertension in 2 dogs and gastrointestinal hemorrhage in 1 dog. Major postoperative (< 1 week after surgery) complications (14/111 [13%]) included seizures or hepatoencephalopathy (7/111 [6%]), cardiac arrest (2/111 [2%]), jugular site bleeding (2/111 [2%]), pneumonia (1/111 [1%]), suspected portal hypertension (1/111 [1%]), and acute death (1/111 [1%]). Median follow-up time was 958 days (range, 0 to 3,411 days). Median survival time for treated dogs was 2,204 days (range, 0 to 3,411 days). Outcome was considered excellent (57/86 [66%]) or fair (13/86 [15%]) in 70 of 86 (81%) treated dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that endovascular treatment of intrahepatic shunts in dogs may result in lower morbidity and mortality rates, with similar success rates, compared with previously reported outcomes for open surgical procedures. Gastrointestinal ulceration was a common finding among this population of dogs, and lifelong gastroprotectant medications are now recommended.

Creation of a gastroenteric anastomosis with endoscopy and percutaneous gastrostomy in pigs.

The authors have previously shown in pigs an immediate transgastric technique for stapling the stomach and jejunum to allow a functioning gastroenteric anastomosis (GEA) with use of balloons and stent placement. The aim of this approach in six pigs was to replicate this procedure by using a flexible endoscopic technique. All pigs had GEAs that were well attached and fully patent.

Management of chylothorax via percutaneous embolization.

PURPOSE OF REVIEW: The purpose of this review is to present a novel radiologic percutaneous transabdominal technique for treating high-output chylothorax by thoracic duct embolization, and to demonstrate that it can be potentially safer than the traditional treatment by surgical open-chest thoracic duct ligation. RECENT FINDINGS: Pedal lymphography is initially performed to opacify large retroperitoneal lymph channels; a suitable duct more than 2 mm in diameter is then punctured transabdominally to allow catheterization and embolization of the thoracic duct under fluoroscopic guidance. If feeding lymphatic channels are too small for catheterization, they can often be occluded by needle disruption. This percutaneous interventional technique, which has been used in 60 patients with mostly high-output chylothorax caused by thoracic surgery, resulted in a 65% cure rate with no morbidity. Back-up surgical thoracic duct ligation was performed promptly on suitable lower risk patients when the percutaneous procedure failed. SUMMARY: We have found that two thirds of patients presenting with life-threatening chylothorax can be safely treated by percutaneous transabdominal thoracic duct blockage. When successful, this novel interventional procedure can obviate repeat major thoracic surgery and shorten hospital stays.

Usefulness of a percutaneous transhepatic coaxial micropuncture needle technique in patients with nondilated peripheral intrahepatic ducts.

OBJECTIVE: I sought to develop an efficacious transhepatic technique for localizing normal or minimally dilated biliary radicles using 25- to 27-gauge needles threaded through 21- to 22-gauge needles. CONCLUSION: The micropuncture needle is a useful adjunct for performing transhepatic cholangiography in patients whose bile ducts are nondilated or in whom the standard transhepatic needle technique has failed.

Management of unremitting chylothorax by percutaneous embolization and blockage of retroperitoneal lymphatic vessels in 42 patients.

PURPOSE: To demonstrate the applicability, technique, and efficacy of percutaneous transabdominal catheter embolization or needle disruption of retroperitoneal lymphatic vessels in the treatment of high-output or unremitting chylothorax. MATERIALS AND METHODS: Forty-two patients (21 men, 21 women; mean age, 56 y; range, 19-80 y) who had chylothorax with various etiologies were referred from the thoracic surgery department for treatment as soon as chylothorax was documented. The thoracic duct was punctured and catheterized via a peritoneal cannula to facilitate embolization with use of microcoils, particles, or glue; if there were no lymph trunks that could be catheterized, attempts were made to disrupt lymph collaterals with use of needles. RESULTS: The thoracic duct was catheterized in 29 patients and embolized in 26 patients. In patients with lymph trunks that could be catheterized, treatment resulted in cure within 7 days in 16 patients and partial response with cure within 3 weeks in six patients. In the patients with lymph trunks that could not be catheterized (n = 16), disruption with use of needles resulted in cure in five patients and partial response in two patients. Cure and partial response rates after thoracic duct embolization and needle disruption were 73.8%, with no morbidity. Surgical thoracic duct ligation was performed in seven patients. The nonprocedural mortality rate was 19%. Follow-up was 3 months or longer. CONCLUSIONS: Effective percutaneous treatment of high-output or medically uncontrollable chylothorax was performed promptly and safely in more than 70% of referred cases. This procedure should be attempted, especially if patients are very ill, before riskier surgical thoracic duct ligation is considered.

Percutaneous transgastric technique for creating gastroenteric anastomoses in swine.

PURPOSE: To develop a percutaneous transgastric procedure for creating a stent-containing gastroenteric anastomosis (GEA). MATERIALS AND METHODS: Acute experiments were performed on eight pigs. A 10-F gastroduodenostomy sheath was used to insert guide wires and targeting devices in the retrogastric jejunal loop; a 6.5-F sheathed trocar needle was then introduced through a second gastric sheath to puncture and catheterize the jejunum through the back of the stomach. Two special sliding anchor pairs were introduced through the catheter to "sandwich" the gastric sheath to the jejunal wall. The jejunum was catheterized a third time between the anchor sets to create a GEA tract for insertion of a stent. The animals were killed at various periods as long as 1 month after the experiments. RESULTS: Snares were the most useful targeting devices for jejunal puncture. Single (n = 1) and double (n = 7) anchor-pair staples effectively prevented intraperitoneal leakage during and after insertion of 12-mm or 14-mm stents. Necropsy of six healthy animals at 5 days, 7 days, 14 days, and 4 weeks (n = 3) showed well-developed patent GEA anastomoses. There was one anesthetic death; one animal was killed at 4 days for obstructive ileus after a difficult transgastric jejunal catheterization. CONCLUSIONS: A GEA can be fashioned through a percutaneous gastrostomy with stapling anchors. This technique may have clinical applications for managing gastric outlet obstruction.

Comparison of sequential versus simultaneous methods of adrenal venous sampling.

PURPOSE: To compare two methods of adrenal venous sampling (AVS) in preoperative localization of adrenal lesions in primary hyperaldosteronism. MATERIALS AND METHODS: Twenty-one patients (13 men, eight women) underwent selective adrenal venous sampling between July 2001 and May 2003. One of the 21 patients underwent repeat AVS, for a total of 22 procedures. In half the procedures (n = 11), simultaneous bilateral adrenal venous catheterization and sampling was performed before and after intraprocedural adrenocorticotropic hormone (ACTH) administration; in the remaining half (n = 11), sequential catheterization of the left and right adrenal veins was performed during continuous ACTH infusion 1 hour before and throughout AVS. Chart review provided procedural data, including sampling intervals and aldosterone/cortisol ratios. Patient records provided clinical data, including blood pressure, serum aldosterone levels, and computed tomography and magnetic resonance imaging findings. Surgical pathology reports confirmed unilateral disease but were not applicable to bilateral disease. RESULTS: Selective AVS was completed successfully in 21 of 22 procedures (95%); the unsuccessful sampling was repeated successfully. Disease lateralized in 13 of 22 cases. Simultaneous bilateral AVS localized unilateral disease in seven of eight cases (88%) and was nondiagnostic in one case (13%), with cases confirmed by surgical pathology reports. Sequential bilateral AVS localized unilateral disease in four of four cases (100%) confirmed by surgical pathology reports, with one lost to follow-up. Bilateral disease was diagnosed in six of 22 cases: two of 11 by simultaneous AVS and four of 11 by sequential AVS. Three of 22 cases demonstrated borderline hormone levels that failed to meet the diagnostic threshold for recommended adrenalectomy. Mean elapsed time between acquisition of right and left samples did not differ between simultaneous and sequential AVS (P = .09). Baseline (prestimulation) sampling did not contribute unique diagnostic information in any case and provided contradictory or confounding information in three of 11 simultaneous AVS procedures (27%). CONCLUSIONS: Sequential bilateral catheterization does not compromise the reliability of time-sensitive AVS. Both simultaneous and sequential AVS are adequate studies; however, obtaining baseline prestimulation samples during simultaneous AVS is unnecessary and increases the cost of the procedure.

In vivo evaluation of a new bioabsorbable self-expanding biliary stent.

BACKGROUND: Bioabsorbable stents may offer advantages for the treatment of benign and malignant biliary strictures, including large stent diameter, decreased biofilm accumulation and proliferative changes, elimination of the need for stent removal and imaging artifacts, and prospects for drug impregnation. However, suboptimal expansion has hampered prior iterations. A new bioabsorbable biliary stent (BioStent) was evaluated in a porcine model. METHODS: BioStents were placed in 8 animals for long-term follow-up. The following were evaluated: accuracy and ease of delivery and deployment, radial expansion, and radiologic visualization. Stent function and biotolerance were assessed by cholangiography, serum bilirubin, and necropsy for histopathology performed in pairs at 2, 4, 6, and 12 months. RESULTS: Stents were delivered without sphincterotomy and were deployed easily, accurately, and with good immediate stent expansion and radiographic visualization. On follow-up, all stents were fully expanded and serum bilirubin levels remained within the normal range. Although there was no clinical evidence of biliary obstruction, filling defects were common at cholangiography. On histopathologic evaluation, there was neither bile duct integration or proliferative change. CONCLUSIONS: The BioStent bioabsorbable biliary stent, modified with axial runners, can be effectively deployed endoscopically, is self-expanding, is visualized radiographically, and remains patent up to 6 months. There was no bile duct integration or proliferative change, which are potential advantages. Stent occlusion and migration remain concerns.

Do simultaneous bilateral tunneled infusion catheters in patients undergoing bone marrow transplantation increase catheter-related complications?

PURPOSE: Secure venous access with multiple lumens is necessary for the care of allogeneic hematopoietic stem cell transplant (HSCT) recipients. The outcomes associated with simultaneous bilateral tunneled internal jugular infusion catheter placement in the HSCT recipient population were investigated in an attempt to determine whether simultaneous introduction of these catheters compounds or magnifies the risks (infection, venous thrombosis) associated with tunneled catheters. MATERIALS AND METHODS: Patients undergoing HSCT and receiving bilateral tunneled infusion catheters in a single procedure were identified using a quality assurance data base. Medical records for the duration of catheterization were reviewed; 43 patients were included in the study (mean age, 42 years; range, 22-56). Diagnoses included acute lymphocytic leukemia (n = 4), acute myelogenous leukemia (n = 8), aplastic anemia (n = 2), chronic myelogenous leukemia (n = 17), chronic lymphocytic leukemia (n = 1), Hodgkin lymphoma (n = 1), myelodysplasia (n = 4), myelofibrosis (n = 2), and non-Hodgkin lymphoma (n = 4). Cox proportional hazards regression analysis was performed to determine differences in infection rates between dual- and triple-lumen catheters. RESULTS: Forty-three pairs of catheters were placed. All met venous access needs for HSCT recipient care. Complete follow-up was achieved for 77 of 87 (89%) catheters. The overall infection rate was 0.25 per 100 catheter-days. The rate was 0.19 and 0.33 for dual- and triple-lumen catheters, respectively (P =.15). Mechanical failure did not differ between catheter types (dual: 0.14 episodes per 100 days, triple: 0.05 per 100 days, P =.2). CONCLUSIONS: Bilateral multilumen tunneled infusion catheter placement in a single procedure using imaging guidance is safe with acceptable outcomes and meets venous access needs for HSCT. There is a trend toward higher infection rates, with more lumens and more mechanical failure with dual-lumen catheters.