Femoral blood flow

Femoral blood flow and coronary flow are measured with electromagnetic flow probes attached to the femoral artery and the circumflex branch of the left coronary artery (LCX), respectively. 

Trlvastal, E-k95, (V) is primarily a vasodilator causing selective increase in femoral blood flow while decreasing splanchnic flow. It caused a reduction in blood pressure, heart rate and respiration which was liihlbited by vagotomy. ... 

A 8-aminoketone (N-1113)(VII) was recently reported to have roughly 3 times the activity of papaverine, on a weight basis, in increasing femoral blood flow in the cat. The authors suggest that since the dose reponse curves for the two drugs are parallel, they may have similar modes of action. 

The ability of the a blocking agent Su 12080 (X) to increase femoral blood flow in anesthetized cats was compared with that of phentolcunine. The drugs were approximately equiactive in this regard and also in reversing peripheral vascular responses both to epinephrine and to norepinephrine. 

In this paper the action of caerulein on pancreatic and on femoral blood flow as well as on other vascular parameters are reported. A comparison with well known vasoactive peptides (angio -tensin II, eledoisin, bradykinin) and with the gastrin-like peptide I.C.I. 50,123 was made in order to elucidate the mechanism by which caerulein acts on pancreatic and on femoral blood flow. I.C.I. 50,123, like caerulein, stimulates gastric and pancreatic external secretions in dogs and in h omans (4) and increases gastric blood flow in the dog (5). 

Mean initial values + S.E. Blood pressure 161 + 4.01 mmHg Pancreaticoduodenal blood flow 16.6 + 2.18 ml/min Femoral blood flow 65 + 5.88 ml/min. 

Percutaneous coronary intervention A minimally invasive procedure whereby access to the coronary arteries is obtained through the femoral artery up the aorta to the coronary os. Contrast media is used to visualize the coronary artery stenosis using a coronary angiogram. A guidewire is used to cross the stenosis and a small balloon is inflated and/or stent is deployed to break up atherosclerotic plaque and restore coronary artery blood flow. The stent is left in place to prevent acute closure and restenosis of the coronary artery. Newer stents are coated with antiproliferative drugs, such as paclitaxel and sirolimus, which further reduce the risk of restenosis of the coronary artery. 

The magnetic targeting force must compete with the force due to linear blood-flow rates of about 0.05 cm/s in capillaries to 10 cm/s in arteries and 50 cm/s in the aorta. Iron-oxide nanoparticles require flux densities at the target site on the order of 0.1 to 1.0 T with field gradients ranging from 8 T/m (femoral arteries) to over 100 T/m for carotid arteries [39, 64]. 

Fig. 6. Rabbit model of femoral arterial thrombosis. A clot is introduced into an isolated segment of femoral artery by injection of thrombin, CaCL, and whole blood. After aging for 1 h, t-PA is infused. Reperfusion is assessed by restoration of blood flow.

Matsuno et al. (1991) reports a method to induce thrombosis in the rat femoral artery by means of a photochemical reaction after injection of a fluorescent dye (rose Bengal, 10 mg/kg i.v.) and transillumination with a filtered xenon lamp (wave length 540 nm). Blood flow is monitored by a pulsed Doppler flow meter. Occlusion is achieved after approximately 5-6 min. Pretreatment with heparin dose-dependently prolongs the time required to interrupt the blood flow. The model also enables the study of thrombolytic mechanisms, which had been evaluated with t-PA. A comparative data for hirudin in various models was carried out by Just et al. (1991). 

Fig. 7. Schematic diagram of the canine femoral artery copper coil model of thrombolysis. A thrombogenic copper coil is advanced to either femoral artery via the left carotid artery. By virtue of the favorable anatomical angles of attachment, a hollow polyurethane catheter advanced down the left carotid artery nearly always enters the descending aorta, and with further advancement, into either femoral artery without fluoroscopic guidance. A flexible, Teflon-coated guidewire is then inserted through the hollow catheter and the latter is removed. A copper coil is then slipped over the guidewire and advanced to the femoral artery (see inset). Femoral artery flow velocity is measured directly and continuously with a Doppler flow probe placed just proximal to the thrombogenic coil and distal to a prominent sidebranch, which is left patent to dissipate any dead space between the coil and the next proximal sidebranch. Femoral artery blood flow declines progressively to total occlusion over the next 10-12 mm after coil insertion.

The eversion graft model for producing thrombosis in the rabbit artery was first described by Hergrueter et al. (1988) and later modified by Jang et al. (1989, 1990) and Gold et al. (1991). A 4- to 6-mm segment of the rabbit femoral or the dog left circumflex artery is excised, everted and then reimplanted into the vessel by end-to-end anastomoses. After restoration of the blood flow, a platelet-rich occlusive thrombus forms rapidly leading to complete occlusion of the vessel. 

Musculoskeletal. Proximal myopathy and tendon rupture may occur. Osteoporosis develops insidiously leading to fractures of vertebrae, ribs, femora and feet. Pain and restriction of movement may occur months in advance of radiographic changes. A biphosphonate, with or without vitamin D, is useful for prevention and treatment. Growth in children is impaired. A vascular necrosis of bone (femoral heads) is a serious complication (at higher doses) it appears to be due to restriction of blood flow through bone capillaries. 

Smooth Muscle. All known calcium inhibitory compounds decrease smooth muscle tone in both the coronary and peripheral circulations (11 , 114, 115, 140, 145-147). Comparative studies using dogs suggest that this effect varies in intensity but surpasses negative inotropic activity (114, 145). Nifedipine, verapamil and perhexiline exhibit their most pronounced vasodilator effects upon femoral arterial blood flow followed by coronary, renal, and mesenteric beds (44, 47,... 

When injected into a systemic artery, microspheres indicate regional blood flow in that organ. Myocardial blood flow was measured in dogs (Fortuin et al. 1971 Weller et al. 1972). Tc-HAM has also been used for measuring regional blood perfusion in the heart (Martin et al. 1973) and the brain in monkeys (Aim 1975). This method has been used for the measurement of the shunted blood through patent arteriovenous connections in the leg after femoral artery injection (Rhodes et al. 1969, 1973). 

Tanaka and Benedek (1974), in a novel and important study, have measured the velocity of blood flow in the femoral vein of rabbit by detecting (in the heterodyne mode) the Doppler shift of laser light introduced into the vein by means of a fiber optic catheter. The light is scattered from the moving erythrocytes in the blood. It is important to recognize that the blood-flow velocity is not uniform across a vein but varies from zero near the vein wall to a maximum in the center. Thus the spectrum observed should be an average over the distribution of velocities of the illuminated erythrocytes, approximately... 

Fig. 5.8.3. The heterodyne correlation function of the scattered light from the blood flow in the femoral vein of an albino rabbit. The lower curve was taken prior to killing the rabbit, and the upper curve was measured just after its death. (From Tanaka and Benedek, (1974.)...

Blood flow rate was measured continuously throughout the experiment using an electromagnetic flow probe and physiograph recorder (Gould, SP2202, and Narco Bio-System, MK III, respectively). The probe was placed proximal to the test section around the femoral artery. 

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