Performance of a hybrid central venous catheter utilized for both peripheral blood stem cell harvest and transplant support of patients undergoing autologous peripheral blood stem cell transplantation.

Patients undergoing autologous peripheral blood stem cell transplantation (PBSC) frequently require the sequential insertion of two central venous catheters, one for leukapheresis and one for transplant support. Hybrid catheters suitable for leukapheresis and long-term use have been increasingly used, but there is limited information regarding their performance and complication rate. The purpose of this study was to determine the performance of the Pheres-Flow hybrid catheter when utilized for both leukapheresis and transplant support, with particular emphasis on the incidence of infectious and occlusive complications. We prospectively analyzed the performance of 92 catheters in 82 consecutive patients who underwent autologous peripheral blood stem cell (PBSC) transplantation. Occlusion was the most frequent complication of this catheter with 29% of the patients experiencing difficulty drawing blood or infusing fluids. Infection was another frequent complication. Twenty-two percent of patients developed catheter-related bloodstream infections and 15 catheters had to be removed because of proven or suspected infection that did not respond to antibiotic therapy. Nevertheless, 77% of patients were able to complete leukapheresis and transplant support with only one catheter. We conclude that the utilization of the Pheres-Flow catheter for both leukapheresis and transplant support is feasible, but that new strategies need to be developed to decrease the incidence of occlusive and infectious complications of hybrid catheters.

Recanalization of thrombosed superficial femoral arteries with a hydraulic thrombectomy catheter in a canine model.

OBJECTIVE: This experiment was conducted to evaluate efficacy and safety of the Oasis thrombectomy catheter on arterial thrombosis in dogs. MATERIALS AND METHODS: Thrombosis was induced in 18 femoral arteries of nine mongrel dogs. Recanalization of the thrombosed femoral artery was performed using a thrombectomy catheter 7-10 days after thrombus induction. Pre- and postprocedural arterial status was documented by angiography. After mechanical thrombectomy, the animals were sacrificed and the femoral arteries were harvested and examined macro- and microscopically. Additionally, in vitro fragmentation was carried out to determine particle size and distribution from the recovered effluent. RESULTS: Subacute thrombosis was successfully created in 15 femoral arteries. Full recanalization was achieved in 80% (12/15) of the thrombosed femoral arteries without any residual thrombus. No significant downstream embolization was documented angiographically. Endothelial denudation was observed in all the treated arteries along with occasional disruption of the internal elastic lamina. No medial injury was seen. Ninety-eight percent of thrombus was liquefied, defined as particles smaller than 15 microm, by the catheter. Particles larger than 400 microm represented 0.27% of the original clot weight. CONCLUSION: Occluded femoral arteries with 7- to 10-day-old thrombus can be efficiently recanalized with the Oasis catheter in dogs without any significant complication. This thrombectomy catheter appears to be highly effective and safe and requires no sophisticated equipment. Blood loss was our major concern regarding use of this catheter but can be minimized by strictly controlling activation time and restricting the inflow into the vascular segment being treated.

Combined percutaneous antegrade and cystoscopic retrograde ureteral stent placement: an alternative technique in cases of ureteral discontinuity.

We describe an alternative method of double J stent placement for ureteral transection following the failure of traditional antegrade and retrograde approaches. Cystoscopically, a guidewire was placed across the distal ureteral segment and was advanced into a urinoma cavity at the level of the transected ureter. Subsequently, an antegrade approach was used to place a gooseneck snare through the proximal ureteral segment into the urinoma cavity. The guidewire was grasped with the snare and pulled through the percutaneous access site. A double J ureteral stent was then placed using the typical antegrade method.

15-Lipoxygenase products of arachidonate play a role in proliferation of transformed erythroid cells.

The role of specific products of the lipoxygenase pathway of arachidonic acid metabolism has been investigated in the Friend erythroleukemia cell line, a model system for erythroid cell differentiation. When triggered with agents such as hexamethylene-bis-acetamide, these cells mature as normal erythroid cells. 15-Hydroxyeicosatetraenoic acid (15-HETE) was identified by reverse-phase high-performance liquid chromatography and by radioimmunoassay as the principal lipoxygenase metabolite produced by Friend cells. Its production was significantly lower (903 +/- 73 pg/ml) in stationary-phase cells compared with logarithmic-phase cells (1,496 +/- 24 pg/ml). In addition, inhibitors of both the cyclooxygenase and lipoxygenase pathways (phenidone, BW 755C, caffeic acid, nordihydroguaiaretic acid and BW 4AC) significantly blocked DNA synthesis (P less than 0.05), whereas neither specific inhibitor of the cyclooxygenase pathway (aspirin or sodium meclofenate) blocked DNA synthesis. The addition of 15-hydroperoxyeicosatetraenoic acid as well as 15-HETE to Friend cells produced an increase in DNA synthesis as assessed by [3H]thymidine incorporation in differentiating cells but not in proliferating cells. These data support a role for 15-lipoxygenase products of arachidonic acid metabolism in maintaining DNA synthesis.