Martin R. Crain

Initial Experience with the Combination of Reteplase and Abciximab for Thrombolytic Therapy in Peripheral Arterial Occlusive Disease: A Pilot Study

PURPOSE To report the efficacy of catheter-directed thrombolysis with a combination of a thrombolytic agent (reteplase) and a glycoprotein (GP) IIb/IIIa platelet receptor antagonist (abciximab) in peripheral arterial occlusive disease. MATERIALS AND METHODS Fifteen patients with lower extremity arterial thromboses (age range, 40-96 y; mean, 73 y) were prospectively enrolled in a protocol approved by the Institutional Review Committee. Nine patients had native arterial occlusions, three (33%) of whom had subacute symptoms (>14 d) and one of whom had chronic symptoms (>3 mo). Four patients had acute arterial graft thromboses. Two patients with lower extremity bypass grafts presented with subacute limb ischemia. All patients received catheter-directed infusion of reteplase (0.5 U/h) in combination with intravenous administration of abciximab (0.25-mg/kg bolus followed by 0.125 microg/kg/min infusion) for 12 hours without systemic heparinization. The thrombolytic success was studied by Doppler ultrasonography (US) and angiography. RESULTS Complete thrombolysis and clinical success was achieved in 14 of the 15 patients (93%). One patient with unsuccessful thrombolysis underwent major amputation. The mean thrombolysis time per Doppler US procedure was 6.8 hours (range, 2-30 h). Angiographic patency was achieved at a mean of 17.5 hours (range, 4-36 h) corresponding to a mean dose of reteplase of 8.8 U. The mean increase in ankle-brachial index was 0.52 (range, 0-0.9). No major hemorrhagic complications occurred. The 30-day primary patency rate was 93%. CONCLUSION The combination of reteplase and abciximab in catheter-directed arterial thrombolysis is feasible and effective. This combination therapy pilot study suggests short thrombolysis times and minimal adverse effects in catheter-directed thrombolytic therapy for peripheral arterial occlusive disease.

Impact of peripherally inserted central catheters on phlebitic complications of peripheral intravenous therapy in spinal cord injury patients.

We investigated the impact of peripherally inserted central catheter (PICC) placement in spinal cord injury patients at high risk for infusion phlebitis. The rate and etiology of phlebitis was investigated in two phases. During Phase I, peripheral IV cannulae and conventional central venous catheters (CVC) were used. During Phase II, patients identified to be at risk for phlebitis received PICCs. The number of peripheral IVs, CVCs and PICCs was tabulated for both phases of the study. Technical, infectious and thrombotic complications were studied prospectively for PICCs and retrospectively for CVCs. We found the rate of phlebitis was 16.5 percent and 2.4 percent for Phases I and II, respectively (p = 0.0002). Three infections occurred in 38 PICCs and one infection was documented in 13 conventional CVCs. The number of peripheral IVs and conventional CVCs was reduced significantly from Phase I to Phase II. No procedural complications, catheter sepsis or clinically apparent venous thrombosis occurred. In conclusion, PICCs reduced the rate of phlebitis thresholds with a low complication rate and reduced the use of peripheral IVs and conventional CVCs.

Hemodialysis Catheter Placement Directly into Occluded Central Vein Segments: A Technical Note

THE continually growing population of patients with end-stage renal disease has further increased the demand for long-term hemodialysis. In 1993, 157,000 people in the United States alone received longterm hemodialysis, according to U.S. Renal Data. Of those patients, approximately 8.9% underwent dialysis with use of a permanent central venous catheter (1). These figures do not include temporary dialysis catheters, and therefore, the role of catheter-mediated hemodialysis remains understated. In this population, the high incidence of central venous stenosis and occlusion poses a challenge for maintaining permanent hemodialysis access. Previously, a central venous stenosis or occlusion eliminated ipsilatera1 access sites and restricted the number of possible alternatives. Recanalization of central venous occlusions in such instances has recently been described in the literature and may provide extended access to previously occluded veins (2,3). We describe an alternative technique for central venous recanalization and successful implantation of a permanent hemodialysis catheter.

Placement of the Palmaz Stent with Use of an 8-F Introducer Sheath and Olbert Balloons

PURPOSE The authors describe a modified technique for delivering Palmaz 30-mm stents. MATERIALS AND METHODS The modification is based on the use of an 8-mm Olbert balloon mounted on a 5.8-F shaft. The Palmaz stent is crimped onto the balloon by using finger pressure only. An 8-F introducer sheath can be used instead of a 10-F sheath. The surface material of the balloon prevents the stent from moving as it is introduced through the sheath and lesion. The balloon has a very small profile after deflation, which means it can be easily removed without dislodging the stent. The balloon can be used for placement of more than one stent. RESULTS Nineteen Palmaz 30-mm stents have been placed with this method, and there have been no complications or difficulties related to this method. In one case, four stents were delivered by using the same balloon. CONCLUSION This modification should reduce the complications of stent delivery, especially in small iliofemoral systems.

Postcontrast CT in the diagnosis and assessment of response to thrombolysis in massive pulmonary embolism.

We present a case of massive acute pulmonary embolism where contrast enhanced helical CT was compared with standard angiography for diagnosis and for monitoring subsequent response to thrombolytic therapy. There was very close concordance of the findings on these modalities suggesting that contrast enhanced helical CT may be an easy and reliable alternative to standard angiography.

Management of Fibrin Sheaths I: Percutaneous Fibrin Sheath Stripping

One of the most vexing issues facing personnel who care for patients undergoing catheter hemodialysis is the formation of fibrin sheath material limiting adequate blood flow rates through these catheters. Next to catheter-related infection, hampered blood flow due to fibrin sheath is the most frequent reason cited for catheter failure and premature removal. This article reviews one of the methods for catheter salvage: percutaneous fibrin sheath stripping. After review of the pathophysiology of fibrin sheath, the technique of mechanical stripping, the published success rates, and the potential complications of the technique are discussed, and a potential algorithm for catheter salvage is proposed.

Percutaneous mechanical thrombolysis and thrombectomy

Devices and methods for mechanically dissolving (thrombolysis) and removing (thrombectomy) thrombus using a percutaneous approach have been developed to address the deficiencies of the previously available methods of treating thrombus, namely Fogarty balloon thromboembolectomy and pharmacologic thrombolysis. Goals of percutaneous mechanical thrombectomy (PMT) include faster, safer, and less expensive treatment of vascular thrombosis, either alone or in conjunction with prior methods. PMT devices have rapidly assumed a role in declotting thrombosed hemodialysis access synthetic grafts, and may eventually play an integral part in many other thrombotic conditions. However, significant device refinement and modification, as well as properly conducted clinical trials, will be necessary before routine use in many applications can be advocated. In this article, each of the PMT devices currently (or soon to be) available in the United States are presented and compared. Each is approved by the Food and Drug Administration for use only in hemodialysis access at the present time.