Search

The objective of the study was to determine if a timed aspiration technique with a 20-ml syringe can be used to predict adequacy of blood flow in tunneled dialysis catheters. Sixteen patients referred for de novo placement or manipulation of failing tunneled hemodialysis catheters had the time it takes to fill a 20-ml syringe with the plunger fully withdrawn measured to the nearest tenth of a second. These measurements were correlated with flow rates recorded in dialysis just prior to (if failed catheter) and in the following dialysis session with adequacy determined as at least 300 ml/min. Syringe-filling time (22 catheters in 16 patients) was plotted against adequacy of dialysis. The mean time to fill a 20-ml syringe was 2.2 sec, with a range of 1.0-4.7 sec. The mean time to fill syringes for catheters with adequate dialysis was 1.7 +/- 0.5 sec, and for inadequate catheters, it was 2.8 +/- 0.8 sec. These differences are statistically significant (p < 0.001). Using a filling time of greater than or equal to 2 sec as a threshold gives the highest sensitivity (100%) for predicting inadequate dialysis while maintaining high specificity (75%). To achieve a specificity of 100%, a 3-sec cutoff would be necessary, but would lead to a sensitivity of only 20%. A simple and objective aspiration technique can be performed at the time of tunneled dialysis catheter placement/manipulation to reasonably predict adequacy of subsequent dialysis.

The purpose of this study was to determine the incidence of central vein stenosis and occlusion following upper extremity placement of peripherally inserted central venous catheters (PICCs) and venous ports. One hundred fifty-four patients who underwent venography of the ipsilateral central veins prior to initial and subsequent venous access device insertion were retrospectively identified. All follow-up venograms were interpreted at the time of catheter placement by one interventional radiologist over a 5-year period and compared to the findings on initial venography. For patients with central vein abnormalities, hospital and home infusion service records and radiology reports were reviewed to determine catheter dwell time and potential alternative etiologies of central vein stenosis or occlusion. The effect of catheter caliber and dwell time on development of central vein abnormalities was evaluated. Venography performed prior to initial catheter placement showed that 150 patients had normal central veins. Three patients had central vein stenosis, and one had central vein occlusion. Subsequent venograms (n = 154) at the time of additional venous access device placement demonstrated 8 patients with occlusions and 10 with stenoses. Three of the 18 patients with abnormal follow-up venograms were found to have potential alternative causes of central vein abnormalities. Excluding these 3 patients and the 4 patients with abnormal initial venograms, a 7% incidence of central vein stenosis or occlusion was found in patients with prior indwelling catheters and normal initial venograms. Catheter caliber showed no effect on the subsequent development of central vein abnormalities. Patients who developed new or worsened central vein stenosis or occlusion had significantly (p = 0.03) longer catheter dwell times than patients without central vein abnormalities. New central vein stenosis or occlusion occurred in 7% of patients following upper arm placement of venous access devices. Patients with longer catheter dwell time were more likely to develop central vein abnormalities. In order to preserve vascular access for dialysis fistulae and grafts and adhere to Dialysis Outcomes Quality Initiative guidelines, alternative venous access sites should be considered for patients with chronic renal insufficiency and end-stage renal disease.

Purpose: The purpose of this study was to evaluate the feasibility, safety, and potential role of carbon dioxide (CO2) as a contrast agent for venography., Methods: Consecutive patients with contraindications to iodinated contrast agents or with unsatisfactory iodinated contrast studies underwent CO2 digital subtraction venography. The images were rated by three experienced angiographers. Image quality and complications were assessed., Results: Over a 14-month period, 66 vein segments were studied in 21 patients. There was good correlation between experienced angiographers on CO2 image quality (Ri = 0.80) and good agreement on diagnosis (k = 0.62). In 91% of the vein segments evaluated with C02 there was interobserver agreement on the diagnosis. Upper extremity veins were adequately imaged with CO2 alone in all (6/6) patients with contraindications to iodinated contrast. Following suboptimal iodinated contrast studies in six patients, CO2 produced significantly better quality upper extremity central vein images (p < 0.05). Pain following injection into peripheral veins was the only CO2-related complication. Inferior vena cava (IVC) filters were successfully deployed with CO2 alone in 78% (7/9) of patients; two required iodinated contrast., Conclusions: Based upon initial experience, CO2 venography can be recommended in patients with contraindications to iodinated contrast or unsatisfactory iodinated contrast studies.

A case of a ruptured middle colic artery is reported. The diagnosis was initially overlooked and eventually made by selective arteriography. Aneurysms of visceral arteries are rare and rupture of them even more infrequent. Awareness of this potentially fatal and treatable entity should enable early detection by selective visceral arteriography. The roles of embolization and surgery in the management of visceral aneurysms are discussed.

Subclavian artery angioplasty is an established treatment for subclavian steal syndrome and arm ischemia caused by subclavian stenosis. We report a case of angina pectoris caused by a subclavian artery stenosis proximal to a left internal mammary-coronary artery bypass graft. Angioplasty was performed without complication and with complete relief of symptoms. Reactive hyperemia was induced in the forearm and hand with a blood pressure cuff prior to angioplasty to increase blood flow to the arm, and to reduce the chance of graft embolization. Repeat angiography 6 months later confirmed continued patency of the subclavian artery and the graft and reversal of the steal physiology. The patient remains symptom free 15 months after angioplasty.

This report describes the thoracic skeletal radiographic findings of rheumatoid arthritis, observed on portable chest examinations of 21 patients. Their pathophysiology is reviewed and additional examples of a recently described finding are illustrated: erosion of the medial surface of the proximal humerus with subsequent pathologic fracture, associated with superior and medial migration of the humeral head. It has been proposed that erosion of the medial aspect of the proximal humerus is due to impingement wear, and that pathologic fracture results from the fulcrum effect of the inferior lip of the glenoid on the humerus. Rheumatoid arthritis is often diagnosed by the clinician rather than the radiologist. However, in acutely ill patients receiving portable chest radiographs, complete history and laboratory findings are often unavailable. Attention to the thoracic skeleton may clarify pleural and/or parenchymal lung disease in these patients.