Guidewire entrapment during deployment of the over-the-guidewire stainless steel Greenfield filter: a device design-related complication. (41/870)

The Greenfield filter (Medi-tech/Boston Scientific, Watertown, Mass) is widely used for the prevention of pulmonary embolism. The latest version is a stainless steel over-the-wire filter. The purpose of the guidewire is to facilitate placement of the device down through the atrium or through tortuous vessels and to prevent tilting of the released filter. A case of entrapment of the guidewire in the filter after deployment through the right internal jugular approach and its recovery by reentering it into the sheath is presented. To prevent this complication, the guidewire should be removed completely before releasing this type of filter. The potential risk of tilting the filter does not outweigh the risk of guidewire entrapment.  (+info)

Development of a novel biomarker of free radical damage in reperfusion injury after cardiac arrest. (42/870)

In a porcine model of cardiopulmonary resuscitation (CPR), we investigated changes in the plasma levels of 8-iso-PGF(2alpha), a marker for oxidative injury, and 15-keto-dihydro-PGF(2alpha), an inflammatory response indicator during the post-resuscitation period after cardiac arrest. Twelve piglets were subjected to either 2 or 5 min (VF2 and VF5 group) of ventricular fibrillation (VF) followed by 5 min of closed-chest CPR. Six piglets without cardiac arrest were used as controls. In VF5 group, 8-iso-PGF(2alpha) in the jugular bulb plasma (draining the brain) increased four-fold. Jugular bulb 8-iso-PGF(2alpha) in the control group remained unchanged. The 15-keto-dihydro-PGF(2alpha) also increased four-fold in the VF5 group. Thus, 8-iso-PGF(2alpha) and 15-keto-dihydro-PGF(2alpha) measurements in jugular bulb plasma may be used as biomarkers for quantification of free radical catalyzed oxidative brain injury and inflammatory response in reperfusion injury.  (+info)

Effect of portal versus jugular methionine infusion on circulating amino acids and nitrogen metabolism in sheep. (43/870)

A double cross-over experiment with 2 rumen-, bilateral jugular vein-, and portal vein-cannulated sheep was performed to determine the influence of route of infusion of methionine on nitrogen balance and blood amino acids. Nutrients were provided solely by intravenous (glucose, amino acids, water soluble vitamins) and intraruminal (VFA, minerals) infusion. Treatments consisted of the infusion of methionine plus serine via either the jugular vein (J) or portal vein (P). The respective order of treatments for the sheep were J, P, J, P and P, J, P, J. Urinary nitrogen was lower and nitrogen balance was greater when methionine was infused intrajugularly. No differences in plasma or blood urea nitrogen were noted. Plasma amino acid (PAA) concentrations showed no significant differences due to treatment. However, whole blood amino acid (BAA) concentrations revealed significantly greater levels of methionine when methionine was administered via the jugular vein. Expression of PAA as percentages of the total resulted in no treatment effects, while percentage expression of BAA showed that methionine was greater and phenylalanine was lower during intrajugular methionine infusion. The central and peripheral methionine infusion routes appeared to influence slightly the subsequent utilization of methionine as determined by effects on BAA levels of methionine. It was demonstrated that results from analysis of circulating amino acids may differ according to whether plasma or whole blood samples are used, and whether the data are expressed as concentrations or proportions.  (+info)

Pressurization facilitates adenovirus-mediated gene transfer into vein graft. (44/870)

We investigated whether application of non-distending hydrostatic pressure facilitates gene transfer into vein grafts. An external jugular vein was placed in a chamber with 100 microl adenovirus solution at a titer of 10(10) pfu/ml and was pressurized to up to 8 atm above ambient pressure for 10 min. Histochemical analysis demonstrated a positive transgene expression in all layers of the vessel wall. Gene transfer with 8 atm pressurization resulted in an approximately 50 times higher transgene expression than that without pressurization. Under 8 atm pressurization, the efficiency of gene transfer reached a plateau at 7.5 min. The application of hydrostatic pressure may improve the effectiveness of intraoperative genetic engineering of vein grafts.  (+info)

Adenoviral-mediated expression of antisense RNA to basic fibroblast growth factor reduces tangential stress in arterialized vein grafts. (45/870)

PURPOSE: The purpose of this study was to test whether basic fibroblast growth factor (bFGF) participates in arterialized vein graft remodeling. METHODS: Rabbits underwent in vivo gene transfer and carotid interposition vein grafting. Segments of external jugular vein were infected with an adenovirus that expressed antisense bFGF RNA (Ad.ASbFGF) at 1 x 10(10) PFU/mL to inhibit new synthesis of bFGF by cells in the vein graft wall. Control rabbits were treated with either adenovirus that encoded beta-galactosidase (Ad.lacZ) at 1 x 10(10) PFU/mL or vehicle (phosphate-buffered saline solution [PBS]). At 3 days, 3 grafts per treatment group were harvested for the determination of gene expression of ASbFGF RNA by reverse transcriptase-polymerase chain reaction. Rabbits were killed, and perfusion was fixed 2 months after the grafting. Total wall thickness and lumen circumference of vein grafts and normal arteries were measured in cross sections. Calculated mean tangential stress (+/-SD) for the ASbFGF-treated group and controls was compared for significance. Grafts were immunohistochemically stained to assess bFGF protein production. RESULTS: Only the grafts infected with the Ad.ASbFGF gene expressed ASbFGF RNA. Grafts that were treated with Ad.ASbFGF displayed lower tangential stress (10.9 +/- 2.3 dynes/cm(2)) than PBS alone (22 +/- 2.8 dynes/cm(2)) or Ad. lacZ-treated controls (20.6 +/- 5.4 dynes/cm(2); P <.001). Tangential stress in the Ad.ASbFGF group was comparable to a normal carotid artery (13.9 +/- 2.1 dynes/cm(2)). The difference in mean total wall thickness was significant among the 3 treatment groups: Ad.ASbFGF, 164 +/- 3.4 microm); Ad.lacZ, 100 +/- 3.3 microm; and PBS, 96 +/- 3.6 microm; P <.01). Luminal circumference was not different among the groups. The Ad.ASbFGF-treated vein graft wall was composed of thick layers of concentric smooth muscle cells and elastin fibers in contrast to the sponge-like appearance observed in control arterialized vein grafts. Reduction in bFGF protein was noted only in the Ad.ASbFGF-treated group. CONCLUSION: Inhibition of bFGF synthesis in vivo with the use of adenoviral gene transfer of antisense RNA to bFGF promotes a vein graft with decreased tangential stress while maintaining the luminal area. The vein graft wall is remodeled and qualitatively resembles an artery so that wall tangential stress in Ad.ASbFGF and normal artery are not significantly different. The lack of significant difference in lumen circumference among groups suggests that wall thickening in the Ad. ASbFGF grafts is not at the expense of luminal narrowing. Our results suggest that ASbFGF RNA expression may represent an effective strategy in limiting the failure of arterialized venous conduits.  (+info)

Internal jugular vein thrombosis in association with the ovarian hyperstimulation syndrome. (46/870)

Thrombosis of the internal jugular vein is a rare entity with the potential for serious consequences. Most of the reported cases of jugular venous thrombosis have occurred in the presence of an indwelling venous catheter, an established hypercoagulable state, or in association with head and neck sepsis. This report presents a case of a patient in whom jugular venous thrombosis developed during the first trimester of pregnancy after in vitro fertilization. Thromboembolism in these circumstances can be related to a condition known as the ovarian hyperstimulation syndrome. The presentation of severe neck pain in pregnant women, especially in those who have undergone assisted reproduction procedures, should prompt evaluation by duplex scan to evaluate the jugular veins for thrombosis. Anticoagulation is the treatment of choice.  (+info)

Jugular venous bulb oxygen saturation in patients with preexisting diabetes mellitus or stroke during normothermic cardiopulmonary bypass. (47/870)

BACKGROUND: The authors hypothesized that patients with cerebrovascular abnormalities or metabolic disorders may experience abnormality in cerebral circulation more frequently than patients without these risks. The current study attempted to assess jugular venous bulb oxygen saturation (SjvO2) in patients with preexisting diabetes mellitus or stroke undergoing normothermic cardiopulmonary bypass. METHODS: Thirty-nine patients undergoing elective coronary artery bypass graft surgery were studied, including 19 age-matched control patients, 10 diabetic patients, and 9 patients with preexisting stroke A 4.0-French fiberoptic oximetry oxygen saturation catheter was inserted into the right jugular bulb to continuously monitor internal SjvO2. Hemodynamic parameters and arterial and jugular venous blood gases were measured at seven time points: (1) after the induction of anesthesia and before the start of surgery, (2) just after the beginning of cardiopulmonary bypass, (3) 20 min after the beginning of bypass, (4) 40 min after the beginning of bypass, (5) 60 min after the beginning of bypass, (6) just after the cessation of bypass, and (7) at the end of the operation. RESULTS: No significant differences were seen in mean arterial pressure, arterial carbon dioxide tension (PaCO2), or hemoglobin concentration among the three groups during the study. The SjvO2 value did not differ among the three groups after anesthesia induction and before surgery, just after the beginning of cardiopulmonary bypass, 60 min after the beginning of bypass, just after the end of bypass, or at the end of the operation. Significant differences between the control group and the diabetic and stroke groups were observed, however, at 20 min and 40 min after the beginning of bypass (at 20 min: control group 62.2 +/- 6.8%, diabetes group 48.4 +/- 5.1%, stroke group 45.9 +/- 6.3%; at 40 min: control group 62.6 +/- 5.2%, diabetes group 47.1 +/- 5.2%, stroke group 48.8 +/- 4.1% [values expressed as the mean +/- SD]; P < 0.05). Also, values in the diabetes and stroke groups were decreased at 20 min and 40 min after the beginning of bypass compared with before the start of surgery. CONCLUSIONS: A reduced SjvO2 value was observed more frequently in patients with preexisting diabetes mellitus or stroke during normothermic cardiopulmonary bypass. It is possible that cerebral circulation during normothermic bypass is altered in patients with risk factors for cerebrovascular disorder.  (+info)

Prevention of intimal hyperplasia by single-dose pre-insertion external radiation in canine-vein interposition grafts. (48/870)

OBJECTIVES: to evaluate the efficacy of single-dose pre-insertion gamma radiation of vein grafts in the prevention of intimal hyperplasia. METHODS: femoral artery interposition grafts with internal jugular vein were inserted in 12 mongrel dogs. The animals were randomly divided into two groups. Immediately before graft replacement, jugular veins were treated with a single dose of cobalt-60 radiation at 14 Gy or received no radiation (control group). Six weeks after graft insertion, the vein grafts were pressure-perfusion fixed and harvested for the histomorphometric analysis. Quantitative data on anastomotic stenosis were calculated from Gilman parameters after cross-sectional image analysis. RESULTS: vein grafts treated with radiation demonstrated significantly decreased neointima formation compared with grafts in the control group. The mean Gilman parameter for the control group was 1.09 S.E.M. 0.34 mm and for the radiotherapy group was 0.65 S.E. M. 0.23 mm (p<0.05). All vein grafts in the radiotherapy group had a decreased amount of intimal and cellular infiltration. CONCLUSION: single-dose external pre-insertion gamma radiation of vein grafts reduced the amount of intimal hyperplasia in this animal model.  (+info)