Reduced Circulation

REDUCED CIRCULATION, a concept introduced by Oppel in 1911 to denote a condition where a limb survives on account of collateral circulation (both arterial and venous) in cases where, in addition to the necessary ligation or resection of an artery to improve circulation, the corresponding vein is also ligated. The question of reduced circulation is connected with the question of the significance of veins for arterial collateral circulation. The first indications of this significance can be found in the early 19th century (Pelikan, 1814; Segalas d'Etchepase, 1824). Both these indications and later ones (Meyer) did not attract attention and were forgotten. The significance of veins for collateral arterial circulation was first elucidated in relation to arteriovenous aneurysms (1906) thanks to one observation by Oppel-Korotkov. A patient with an arteriovenous aneurysm of the left subclavian vessels underwent three operations in one day: 1) Ligation of the feeding artery according to Aiegu. After the operation, severe pain in the limb, it was deathly pale, complete ischemic paralysis. It was assumed that the vein was intercepting collateral arterial blood through the aneurysm. 2) Ligation of the draining vein from the aneurysm. Temporary improvement, then the same pains, paralysis, deathly pallor, by evening a blister at the base of the big toe. 3) Excision of the aneurysm. During the operation, a second dilated draining vein was found. Result: disappearance of paralysis, arterial hyperemia of the peripheral part of the limb, which lasted for 1¹/2 days, cessation of pains, complete recovery. The cited observation established that in arteriovenous aneurysms, ligation of the feeding artery is accompanied by the outflow of collateral arterial blood through the aneurysmal sac into the veins. This observation explained why after ligation of the artery feeding an arteriovenous aneurysm, gangrene of the limb is so often observed. Experimental studies by Ney on arteriovenous fistulas have finally proven that veins actually intercept collateral arterial blood. After creating an arteriovenous fistula, arterial blood pressure in the peripheral part of the artery (below the fistula) usually falls, as part of the arterial blood flows into the vein. The veins, under the pressure of the arterial blood stream, dilate. If after forming an arteriovenous fistula the artery is compressed above it, then the pressure in the peripheral part of the artery falls extremely low. Exclusion of the artery from the fistula, i.e., compression of the artery above and below the fistula, returns the pressure in the peripheral part of the artery to the normal level of collateral-arterial. From this, a practical conclusion was drawn: in the treatment (operative) of arteriovenous aneurysms, it is necessary to separate the inflow and outflow channels. If vascular suture is not used, then it is necessary to resect the arteriovenous aneurysm, as this 1) satisfies the requirement of separating the inflow and outflow channels, 2) brings the width of the inflow channel (artery) and outflow channel (vein) into correspondence, i.e., creates reduced circulation. Based on the facts presented, Oppel assumed that even in the absence of pathological communication between an artery and a vein (fistula, aneurysm), ligation of one artery disrupts the correspondence of the width of the inflow and outflow channels. After ligation of the artery, the remaining free vein turns out to be too wide, and therefore can intercept collateral arterial blood: the peripheral part of the limb may fall into a state of ischemia and even gangrenize. To improve the blood supply to the peripheral part of the limb, it is necessary to add the ligation of the corresponding vein to the necessary ligation of the artery. Bringing the width of the inflow and outflow channels into correspondence creates reduced circulation. Individual clinical observations by the author showed that in reality, after ligation of an artery, the peripheral part of the limb sometimes appears deathly pale; adding the ligation of the vein (reduced circulation) is accompanied by the appearance of arterial hyperemia in the periphery and prevents the danger of gangrene development. Oppel's observation was confirmed by opponents of the doctrine of reduced circulation (Punin). Some authors confirm the beneficial value of adding vein ligation to artery ligation (Wolf, Heidrich), others (Punin, Bogoraz) deny it. The doctrine of reduced circulation was subjected to thorough experimental development. It was clarified that organs with insignificant arterial collaterals (kidneys, small intestine as a whole) cannot be saved from necrosis if, along with ligation of the renal or superior mesenteric artery, the corresponding vein is ligated, i.e., reduced circulation is created. The matter is different with respect to limbs. If, along with ligation of the abdominal aorta above the bifurcation, ligation of the inferior vena cava is added, then instead of paralysis of the lower limbs (from ligation of the aorta alone), paresis occur; paralysis of the urinary bladder—a usual companion of aorta ligation—is absent with reduced circulation. Experiments on animals showed that vein ligation, added to artery ligation, always increases collateral-arterial pressure. At the same time, it turned out that ligation of a higher-order vein increases collateral-arterial pressure more than ligation of a vein of the same name: ligation of the inferior vena cava, added to ligation of the femoral artery, increases pressure in the peripheral end of the latter more than ligation of the femoral vein. Shapiro's research discovered that after simultaneous ligation above the bifurcation of the abdominal aorta and the inferior vena cava in the hind limbs of dogs, stasis of blood does not occur. If one compares the speed of blood flow in the arteries of the hind limbs after ligation of one artery and with reduced circulation, the following is found: in the first hours, the speed of flow is greater in the first case than in the second; after 24 hours, the speed of blood flow with reduced circulation is greater than with ligation of one artery. Thus, the experiment showed that reduced circulation is more beneficial for the limb than collateral-arterial circulation: the blood filling of the limb (Revyakin), the speed of blood flow, and collateral-arterial pressure are improved. This gain in blood filling was proven plethysmographically. Practically, with respect to humans, one should adhere to the following viewpoint: reduced circulation can save a limb from gangrene in cases where arterial collaterals exist and only need to be dilated. When arterial collaterals are sufficiently developed, then with necessary artery ligation, one can do without reduced circulation. One can judge this as follows: if after artery ligation the peripheral part of the limb is deathly pale, and compression of the vein causes arterial hyperemia in the peripheral part, then vein ligation is doubly indicated. If the peripheral part of the limb after artery ligation is pink, and even the peripheral pulse can be felt (for example, after ligation of the subclavian artery, the pulse in the radial artery), then one can do without reduced circulation. If compression of the vein after artery ligation is not accompanied by reddening of the periphery, then one can think either of the absence of arterial collaterals or of the difficulty of their dilatation due to falling general arterial pressure (acute anemia, shock). In such a case, according to Oppel, it is still worth adding vein ligation, while at the same same time taking measures to increase arterial pressure (blood transfusion). The doctrine of reduced circulation is applicable primarily to limbs. In experiment, it is not possible to prove the beneficial value of reduced circulation for the blood supply of the brain by adding to the ligation of the common carotid artery the ligation of the corresponding vein (external jugular in dogs). In the clinic, a particularly convincing example of the usefulness of reduced circulation should be considered the case of adding to the ligation of the common carotid artery the ligation of the internal jugular vein. Attention was first drawn to this by Hagen-Thorn; this is fully confirmed in the textbook by Bir-Brown-Kümmel. Since in 'spontaneous' gangrene the arteries usually thrombose, while the veins remain patent, a discrepancy arises between the inflow and outflow channels. This is why Oppel, even in this disease, proposed vein ligation as a palliative measure of treatment, which creates reduced circulation. At first, ligation of the popliteal vein was intended, but then the ligation was raised to the femoral vein (Fedorovich, Petrov). There are individual authors who have a negative attitude toward the mentioned operation (Punin), but the majority of domestic and foreign surgeons (Bastos and others) recognize its beneficial value. Statistics reveal (Nekrasov) that in 40% of cases, vein ligation in spontaneous gangrene brings temporary benefit. To dilate the arterial collaterals, reduced circulation can be strengthened by sympathectomy.