Occlusion catheter

Routine use of in-line filters with TNA solutions is controversial. A 1.2-micrometer filter can be used to prevent catheter occlusion caused by precipitates or lipid aggregates, and to remove Candida albicans. 

Hardy, G., and Ball, P. (2005). Clogbusting Time for a concerted approach to catheter occlusions Curr. Opin. Clin. Nutr. Metab. Care 8, 277-283. 

Heparinization of the fluid infused through an umbilical arterial catheter with heparin 0.25 units/ml reduces the likelihood of catheter occlusion heparinization of flushes without heparinizing the infusate is ineffective (20). 

Technical problems after intrathecal opioids are rare, although catheter occlusion and leakage of CSF have been reported (SEDA-17, 85) (102-104). In 121 patients with... 

PN solutions should be administered with an infusion pump to ensure consistent and controlled delivery of the solution. The intravenous administration line may include an in-line filter at a point prior to connection to the catheter. A 0.22-micron filter is recommended for use with CAA-dextrose solutions to remove particulate matter, air, and any microorganisms that may be present in the solution from prior manipulations of the admixture or the administration line. Because the average size of IVLE particles is approximately 0.5 micron, IVLEs administered separately from the CAA-dextrose solution must be piggybacked into the PN line at a site beyond the in-line fllter. Routine use of in-line filters (>0.22 micron) with TNA solutions is controversial. However, the FDA recommends use of a 1.2-micron filter, which may be effective in preventing catheter occlusion due to precipitates or lipid aggregates. This filter size is also reported to remove Candida albicans. 

With peripheral blood stem cell harvesting, the most frequent problems relate to central venous catheter occlusion and bone pain in association with the G-CSF priming. Infectious complications during harvesting were experienced in 16% of patients during the PBSC harvesting. 

For large lumen microcatheters, it is necessary to use a 0.021 or 0.025-in. pusher wire to avoid catheter occlusion. In the newer microcatheters (Renegade Hi-Flo, Boston Scientific Progeat 2.7, Terumo or Embo-cath. Biosphere Medical), the use of standard 0.016-in. pusher wires will cause trapping of microcoils between the inner diameter of the microcatheter and the microcoil. To avoid this the squirt technique is utilized or a larger pusher wire is required. 

Robinson LA, Wright BT (1982) Central venous catheter occlusion caused by body-heat-mediated calcium phosphate precipitation. Am J Hosp Pharm 39(1) 120-121... 

Fig. 4.19 Deep (A) and superficial (B) anatomic relationships of the Magney approach to subclavian vena puncture. Point M indicates the medial end of the clavicle. X defines a point on the clavicle directly above the lateral edges of the clavicular/subclavius muscle (tendon complex). Rl. Point D overlies the center of the subclavian vein as it crosses the first rib. St, the center of the sternal angle Cp, coracoid process Ax, axillary vein star, costoclavicular ligament open circle with closed circle, costoclavicular ligament open circle with closed circle inside, costoclavicular ligament sm, subclavius muscle. The arrow points to Magney s ideal point for venous entry. (Magney JE, Staplin DH, Flynn DM, et al. A new approach to percutaneous subclavian venipuncture to avoid lead fracture or central venous catheter occlusion. Pacing Clin Electrophysiol 1993 16(11) 2133-2142, with permission.)...

Magney JE, Staplin DH, Flynn DM, et al. A new approach to percutaneous subclavian needle puncture to avoid lead fracture or central venous catheter occlusion. PACE 1993 16 2133. 

The issue of catheter clearance was discussed at a National Association of Vascular Access Networks (NAVAN) consensus conference in 2000 (Haire and Herbst 2000). The results of the conference can be summarized as (1) the inability to withdraw and/or infuse are the most frequent signs of catheter occlusion (2) treatment depends on etiology of obstruction (3) tissue plasminogen activator (t-PA) is considered the drug of choice for thrombotic occlusions (Table 6.1) and (4) future investigations for t-PA include thrombotic prophylaxis, adjunctive use with antibiotics, and infusions for venous thrombosis and embolism. Ponec et al. (2001) performed a prospective randomized trial comparing t-PA and placebo for the treatment of occluded central venous cath-... 

Shah, P.S., Shah, V.S., 2008. Continuous Heparin Infusion to Prevent Thrombosis and Catheter Occlusion in Neonates with Peripherally Placed Percutaneous Central Venous Catheters. The Cochrane Library. 

These microspheres are precisely calibrated, spherical, hydrophilic, microporous beads made of tris-acryl co-polymer coated with gelatin. They come in defined range of sizes, ranging from 40 to 1200 pm in diameter. Their smooth hydrophilic surface, deformability and minimal aggregation tendency have been shown to result in a lower rate of catheter occlusion and more distal penetration into the small vessels [32]. Their efficacy has been evaluated in several conditions, and vdien compared to the standard polyvinyl alcohol particles (PVA) particles, a deeper penetration and embolization of smaller and more peripheral vessels may be achieved. This distal embolization may limit the development of any collateral blood supply. Also, in a study where PVA particles and tris-acryl microspheres of similar size were compared, the level of vascular occlusion with calibrated tris-acryl microspheres precisely correlated with particle size whereas the level of vascular occlusion with PVA particles did not. Another study has demonstrated that in embolized tumors. 

Jacobs, B. R. (2003). Central venous catheter occlusion and thrombosis. Critical Care Clinics, 79(3), 489-514. 

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