As has been shown, arteriosclerosis of the splanchnic vessels not infrequently occurs, and an embolusor thrombus may completely occlude the superior mesenteric artery.
The danger of an embolus plugging one of the smaller arteries is great and probably happens more often than we think.
As I told you, she's had an embolus in one artery of the brain.
Supervening upon her ordinary cardiac attack after supper, Mrs. Maldon had had, in the night, an embolus in one artery of the brain.
She had still no conception of what an embolus was; but she naturally assumed that Louis could define an embolus with exactitude.
And yet the mere naming of the affliction eased her, although she had no conception of what an embolus might be.
Hastings also states that in a patient who died from pulmonary embolism, after an operation, a thrombus occupied the right cardiac ventricle, and he thought it possible that this intraventricular clot furnished the embolus (Fig.
An embolus occupied the pulmonary artery, resembling a blood-clot found in the left common and internal iliac veins.
When the embolus is large the patient sometimes dies in a few minutes (see p.
One month later he was seized with urgent dyspnœa and signs clearly indicating the lodgment of an embolus in the pulmonary artery.
In some instances this is an assumption, but there are many in which an embolushas been demonstrated, and a few in which the source has been detected.
Sometimes a portion of the clot in the sac is separated and becomes impacted as an embolus in the artery beyond, leading to thrombosis which first occludes the artery and then extends into the sac.
When an embolus becomes impacted at the bifurcation of the popliteal, if gangrene ensues it usually spreads well up the leg.
The commonest forms of embolus are portions of thrombi or of fibrinous formations on the valves of the heart, the latter being usually infected with micro-organisms.
Absence of pulse in one radial vessel, while it is present in the other, shows the presence of an obstacle to the circulation on one side, which may be an aneurism, or an embolus plugging the artery.
If the obstructed artery is not terminal, the embolus may produce no further disturbance, the collateral supply of blood through the anastomoses sufficing for the nutrition and function of the part.
When the embolus arises from a septic thrombus, the results differ from those above described.
When an embolus is found, or embolism suspected, the source is always {64} to be searched for in those regions from which the affected part receives its blood.
An embolus is a foreign body in a blood-vessel, usually too large to pass through the smallest capillaries, and the disturbances resulting from its presence are included under the term embolism.
The mechanical effect of an embolus is manifested by the obstruction it offers to the circulation, and the degree of the obstruction depends upon the size, shape, and density of the embolus and the nature and size of the vessel obstructed.
When the embolus reaches a point beyond which it cannot pass, the resulting disturbance depends essentially, as shown by Cohnheim, upon the presence or absence of arterial anastomoses beyond the place of obstruction.
The source of arterial and portal emboli is usually found with ease, while the pulmonary embolus may come from so wide a region, the body-veins, that much time may be spent before its place of origin is discovered.
If theembolus does not completely obstruct at once, it soon becomes sufficiently large for this result to ensue in consequence of a secondary coagulation.
If, however, the vessel is a terminal artery, and the embolus is completely obstructing, the supply of arterial blood must be wholly cut off from the region beyond the seat of obstruction.
The embolushas become an obstructing thrombus, and its removal is accomplished in the manner already stated in connection with the subject of thrombosis.
This point usually corresponds with a place of bifurcation, and theembolus frequently rides the wall separating the branches.
Again, an aneurism may cause a great difference between the two radial pulses, or, possibly, an embolus may occlude one of the radial vessels, annulling its pulsation.
Very often the vessel whose occlusion by a suppurating embolus has caused the mischief is destroyed, and hence no communication with the abscess-cavity can then be traced.
Excepting these cases there must be many in which no emboluscan be found, because none existed; an unknown septic substance has excited the suppurative inflammation.
Admitting the presence of the embolus originally, its disappearance is readily understood by reference to the changes induced by suppuration.
In one case Merkel found an embolus in a small artery leading to an ulcer {511} of the duodenum.
There are many examples of hepatic abscess connected with dysenteric ulcerations of the intestine in which no emboluscan be found.
