Comparison of parenteral nutrition and enteral feeding with pectin in experimental colitis in the rat.

The effect of a pectin-supplemented enteral diet on experimental colitis was compared with parenteral nutrition and with a pectin-free enteral diet. Forty-five rats had feeding catheters placed into either the stomach (IG, n = 31) or the superior vena cava (IV, n = 14) and then received acetic acid (colitis) or saline (control) enemas. After the enema, all rats received the same diet, either IG or IV, for 6 d except for 15 rats (IGP, 9 colitis and 6 controls), which had 1% pectin added to the diet. At the end of the feeding period the IGP group had significantly less colonic inflammation and/or necrosis than either IV (p less than 0.03) or IG (p less than 0.04) groups. Nitrogen balance, serum albumin, total iron-binding capacity and body weight did not differ significantly among dietary regimens. Thus, the degree of bowel injury in experimental colitis was decreased when animals were fed a pectin-supplemented enteral diet and this effect was independent of nutritional status.

Long-term follow-up of the Palmaz stent for iliac occlusive disease.

BACKGROUND: Thirty-eight limbs with iliac occlusive disease were treated with Palmaz stents from 1987 through 1991. METHODS: Indications for stent utilization included dissection induced by percutaneous transluminal balloon angioplasty (PTA) (10), restenosis after PTA (nine), post-PTA residual stenosis (nine), multiple stenoses or occlusion (five), and unfavorable location (five). RESULTS: The ankle/brachial pressure index increased from 0.53 +/- 0.27 to 0.8 +/- 0.26 after stent deployment. The intraluminal pressure gradient decreased from 31.9 +/- 16.3 to 0.9 +/- 2.2 mm Hg after stent deployment. Complications included pseudoaneurysm (one), arteriovenous fistula (one), iliac perforation (one), groin hematoma (two), and occlusion (two). Follow-up arteriogram showed stenosis proximal or distal (n = 4) or within the stents (n = 4). These were treated with PTA or stents. Two patients required an aortobifemoral graft. Nine patients have died. Life table analysis showed a 1-, 3-, and 5-year primary and secondary cumulative patency of 87% +/- 5.9%, 74% +/- 8.2%, and 63% +/- 10% and 91% +/- 5.1%, 91% +/- 5.6%, and 86% +/- 7.6%, respectively. CONCLUSIONS: Palmaz stents, often required to salvage a PTA failure, appear to maintain overall patency at a high level. However, intimal hyperplasia and the progression of atherosclerotic disease may result in a need for additional procedures to obtain this favorable outcome.

Radiologic percutaneous gastrostomy: results in 56 patients with head and neck cancer.

OBJECTIVE: The establishment of a direct enteral feeding route is critical in the overall treatment of many patients with head and neck cancer. Use of radiologic percutaneous gastrostomy (RPG), the newest technique for gaining enteral access, has not been studied in such patients extensively. This study evaluated the indications, technique, success rate, and complications associated with RPG in patients with head and neck cancer. STUDY DESIGN: Retrospective. METHODS: A comprehensive chart review was undertaken of 56 patients with head and neck cancer treated at a tertiary care institution who had undergone successful or attempted RPG at some point during their treatment course. RESULTS: Most study patients had advanced oropharyngeal squamous cell carcinoma. The most frequent indications for RPG were dysphagia/aspiration following tumor resection (n = 26) and dysphagia following completion of single- or combined-modality therapy (n = 22). The success rate of attempted RPGs was 98.2%. The overall complication rate for RPG was 12.7% (10.9% minor and 1.8% major). CONCLUSIONS: RPG is a valuable tool for establishing enteral nutrition in patients with head and neck cancer. Advantages of RPG include high success rate despite obstructing lesions, low complication rate, time efficiency and scheduling ease compared with intraoperative percutaneous gastrostomy (PEG) by a second team, no reported tumor seeding of the tube site, and the fact that postoperative RPG allows for more accurate selection of patients who require a gastrostomy tube.

Detection of total parenteral nutrition-induced fatty liver infiltration in the rat by in vitro proton nuclear magnetic resonance.

In an effort to determine if NMR techniques might be used to detect TPN-induced hepatic steatosis, the NMR spin-lattice (T1) and spin-spin (T2) relaxation times were measured on liver tissue from rats who received one of five dietary regimens: (1) 100% of nonprotein calories as lipid (Fat); (2) a mixture of 50% lipid and 50% glucose nonprotein calories (50/50); (3) 100% of nonprotein calories as glucose (CHO); (4) intravenous saline and standard laboratory rat chow (Saline); and (5) rat chow alone (Oral). The parenteral diets were isonitrogenous and isocaloric. Serum liver function tests were also measured. Animals in the Fat and 50/50 groups had the greatest amounts of liver fat and significantly longer T1 and T2 times (p less than 0.01) than any other group. Furthermore, the correlation of T2 time with liver fat content (r = 0.82) was far superior (p less than 0.001) to that of serum SGPT (r = 0.48) which was the only liver function test which correlated significantly with liver fat content. In a multiple linear regression analysis, T1 and T2 predicted liver fat content with an r value of 0.84 (p less than 0.001). These data suggest that in vivo NMR imaging techniques might be used to detect TPN-induced fatty infiltration of the liver noninvasively.

Computed tomography of uterine sarcomas.

Uterine sarcomas are rare tumors, comprising only 2% of uterine malignancies. Abdominal and pelvic computed tomography (CT) of 14 patients with pathologically proven uterine sarcomas were reviewed. The average age of patients in our series was 64 years. The primary tumor measured between 4 and 30 cm. CT characteristics of uterine sarcomas included a low density mass within the uterine cavity in 12 of 14 cases. In two cases the mass was nearly isodense with uterus. Tumor necrosis was present in eight cases. Two patients presented with sarcomatosis, two demonstrated nodal spread, and one had liver metastases. Hydronephrosis was seen in three cases.

Complications of interventional radiology: an imaging overview.

The growth of interventional radiology has contributed to the development of more complex procedures applicable to an increasing patient population, with maintenance of low complication rates. However, due to its invasive nature, potential complications will always be associated with each procedure. Prompt recognition of these complications allows for rapid treatment with decreased patient morbidity and mortality. This overview provides detailed statistics and diagnostic imaging for evaluation of a wide spectrum of complications from hepatobiliary, renal, and vascular interventional procedures.

Change in the pattern of adrenal venous sampling over time in patients with primary aldosteronism.

We report six patients with primary aldosteronism who had serial adrenal venous sampling. Patients with contralateral suppression of aldosterone to cortisol ratio compared with that in inferior vena cava developed lateralization over time whereas patients without contralateral suppression remained with a bilateral pattern.

Hemodialysis catheter placement and management.

Hemodialysis catheters are an integral part of the delivery of hemodialysis. While catheters play an important role in the patient undergoing hemodialysis, catheters should be considered a bridge to more permanent forms of dialysis access in most patients. Recent advances in catheter technology, access techniques, and choice of access sites have improved outcomes associated with hemodialysis catheters. The placement and management of hemodialysis catheters by interventional radiologists have played an important role in these advances, and interventional radiologists are taking an increasingly active role in the research and development of catheters and catheter insertion techniques. The present status of hemodialysis catheters is reviewed.

Postcatheterization retroperitoneal hematoma due to spontaneous lumbar arterial hemorrhage.

A patient developed retroperitoneal hemorrhage after cardiac catheterization, initially thought to be a complication of the puncture. Diagnostic evaluation revealed the source to be spontaneous bleeding from a lumber artery, which was successfully embolized. Spontaneous hemorrhage is a recognized complication of anticoagulation therapy and must be considered in the differential diagnosis even in the face of a seemingly obvious source of bleeding.

Use of a guard wire during transjugular liver biopsy with the Colapinto needle. Technical note.

The authors describe a simple modification of the Colapinto transjugular biopsy needle in which a 0.045-inch stainless steel guide wire is used. The technique allows easier and safer passage of the needle through the introducer sheath to avoid complications such as sheath puncture and expedite the procedure. The technique and successful results in seven patients are described.

Percutaneous translumbar inferior vena cava cannulation for hemodialysis.

The purpose of this study was to evaluate the percutaneous translumbar approach for long-term hemodialysis catheter access. Seventeen double-lumen hemodialysis catheters were placed percutaneously from the right flank to the inferior vena cava in 12 patients. Catheter placement was successful in all patients. Adequate flow rates were obtained. Seven episodes of thrombosis-related access failure occurred (0.33 episodes/100 days at risk). Two catheters were removed and five catheters were managed with urokinase infusion. Six episodes of infection occurred (0.28 episodes/100 days at risk). Four required catheter removal. Two catheters were removed after defects developed in the catheter. Five catheters were removed electively because catheter hemodialysis was discontinued. Four catheters remained in place. Cumulative patency was 52% at 6 months and 17% at 12 months. Translumbar inferior vena cava hemodialysis catheters represent a valuable alternative in cases in which traditional catheter sites have failed.

Radial artery pseudoaneurysm complicating a Brescia-Cimino dialysis fistula.

The authors describe an unusual case of radial artery pseudoaneurysm in a patient with a Brescia-Cimino fistula. Evaluation of a pulsatile mass on the patient's forearm which occurred after hemodialysis led to a nondiagnostic fistulogram. Color flow ultrasound was helpful in identifying the nature of the abnormality, which was subsequently confirmed arteriographically. This case illustrates that fistulography is not 100% sensitive and should be supplemented with other imaging modalities when the clinical and fistulographic findings are discordant.

CT and anatomic study of postcatheterization hematomas.

The appearance of hematomas resulting from transfemoral catheterization as depicted with computed tomography (CT) has been infrequently reported. The authors devised a system for classifying the CT appearance of such iatrogenic hematomas that is based on the anatomic location and route of bleeding. There are four different types of hematomas: retroperitoneal, intraperitoneal, groin and thigh, and abdominal wall. Bleeding spreads along the fascial planes, and the type of hematoma probably depends on whether the bleeding is confined to the femoral sheath or spreads into the femoral triangle. Recognition of the different types is essential as they may have different clinical implications.

Bleeding complications of femoral catheterization: CT evaluation.

Computed tomographic (CT) scans and clinical data were reviewed in 21 patients with significant hematoma occurring after catheterization. The procedures included percutaneous transluminal coronary angioplasty (n = 15), cardiac catheterization (n = 2), peripheral angioplasty (n = 2), valvuloplasty (n = 1), and venous access catheterization (n = 1). Clinical data including medications, transfusion requirements, and sequelae were obtained by reviewing the patients' charts. Four distinct types of postcatheterization bleeding were identified at CT: retroperitoneal, intraperitoneal, groin and thigh, and abdominal wall hematomas. CT scans contributed to treatment in all patients by helping indicate the need for more intensive monitoring and by helping predict the potential need for surgery. Sequelae included the need for blood transfusions in 17 patients (mean of 5 units of blood in each patient receiving transfusion) and surgery in two patients for vessel repair.

Recent trends in central venous catheter placement: a comparison of interventional radiology with other specialties.

The authors determined changing trends and growth in tunneled and nontunneled central venous catheter placement procedures. With use of Medicare billing data for tunneled and nontunneled catheter placement, a comparison was made among interventional radiology (IR), surgery, anesthesia, and internal medicine. There has been substantial growth in the placement of central venous catheters. Currently, a minority of these procedures are performed in IR departments. However, there has been significant growth in the radiologic placement of both types of catheters.

Percutaneous creation of arteriovenous hemodialysis grafts: work in progress.

PURPOSE: To develop a technique of percutaneous creation and/or revision of arteriovenous hemodialysis access grafts, and to study the feasibility of the technique in the acute setting. MATERIALS AND METHODS: Arteriovenous shunts, consisting of silicone-covered Wallstents 6 (n = 10) or 8 (n = 1) mm in diameter and 11-17 cm in length, were created in 10 mongrel dogs. All shunts were created percutaneously except one, in which the carotid artery was exposed surgically and the jugular vein accessed percutaneously to create a straight external graft. All other grafts were femoral loops (femoral artery to femoral vein). Eight were tunneled subcutaneously and three were left external. All shunts were delivered through 10-F peel-away sheaths. RESULTS: The 11 shunts were allowed to flow for a mean of 4 hours (range, 1.0-6.5 hours) before the animals were killed. Leakage around the "anastomoses" was not observed. Leaks in the silicone covering were observed, resulting in one early shunt failure. Two attempted survival experiments were aborted due to early shunt dislodgment at 1.5 and 3.5 hours. CONCLUSIONS: Percutaneous arteriovenous shunt creation is feasible through acceptably small sheaths. Peel-away sheath placement of the stent circumvents the technical problem of placing a closed device into both artery and vein. This technique may allow percutaneous revision of existing hemodialysis access grafts and possibly de novo creation of grafts in humans, but modification of the grafts will be needed to prevent dislodgment.

Percutaneous removal of "dropped" gallstones after laparoscopic cholecystectomy.

Laparoscopic cholecystectomy is becoming increasingly popular in the treatment of symptomatic gallstones, offering improved patient satisfaction and decreased hospital stays. The authors describe a patient in whom infected bile and gallstones were spilled or "dropped" during laparoscopic cholecystectomy. Most of the gallstones ranged from 5 to 8 mm in diameter; one gallstone was 11 x 17 mm. An abscess formed around the stones, and percutaneous stone removal was performed 1 week after abscess drainage. The size of the retained gallstones is important. Stones smaller than 1 cm in diameter can usually be removed via a 30-F sheath by conventional means, whereas stones larger than 1 cm in diameter require fragmentation before removal.

Comparison of Gianturco Z stents and Wallstents in a hemodialysis access graft animal model.

PURPOSE: To compare the primary patency of two structurally different metallic stents in an animal model of hemodialysis access grafts. MATERIAL AND METHODS: Nineteen synthetic femorofemoral arteriovenous shunts were created in 10 dogs. After a 1-month period of maturation (during which one graft thrombosed), stents were placed spanning the venous anastomosis. The grafts were divided into two treatment groups (Wallstent, n = 6, and Gianturco stent, n = 6) and a control group with no stent (n = 6). Fistulograms and pressure measurements were obtained at monthly intervals for 6 months or until thrombosis of the graft. RESULTS: Mean graft patency in the Wallstent group (112 days +/- 30) was significantly shorter than in the control (157 days +/- 32, P < .03) or Gianturco (157 days +/- 32, P < .05) groups. Patency in the Gianturco stent group was no different from that in the control group. Stenosis due to intimal hyperplasia within the stents appeared greater in the Wallstent group but did not achieve statistical significance. One Wallstent migration, three Gianturco stents shifts, and two Gianturco stent breakages occurred. Histologic examination revealed a necrotizing vasculitis in the portion of vein containing the stent in all grafts treated with the Gianturco stent but not in any other grafts. CONCLUSION: In an animal model of hemodialysis access grafts, the Gianturco stent had longer primary patency than the Wallstent when placed across the venous anastomosis. However, stent fractures and focal necrotizing inflammation may limit the use of the Gianturco stent in hemodialysis access.

Evaluation of venous injury caused by a percutaneous mechanical thrombolytic device.

PURPOSE: To study venous injury caused by a prototype percutaneous mechanical thrombolytic device. METHODS: Simulated thrombolysis was performed using the device, or the Fogarty balloon catheter (FBC) as control, in the infrarenal inferior vena cava (IVC) of 40 New Zealand white rabbits. Venous injury was evaluated by cavography, Evans blue dye staining, and histology at 0, 1, and 6 weeks postprocedure. RESULTS: Both devices resulted in near complete endothelial denudation acutely. No differences in reendothelialization were noted at any time in the proximal and mid-IVC, but there was significantly greater reendothelialization in the distal IVC in the rabbits treated 6 weeks earlier with the device (p < or = 0.04). Additionally, the inner luminal diameter at necropsy for the 1-week rabbits treated with the FBC was significantly narrower in the distal and middle sections of the IVC when compared with the device (p < or = 0.02 for both segments). There was no luminal diameter difference at 0 or 6 weeks. CONCLUSION: Based on a rabbit model, venous injury from the device was found to be similar to, and in the distal IVC less than, the routinely used FBC.