Quebracho

QUEBRACHO, Aspidosperma quebracho bianco, a tree of the Apocynaceae family, growing in Argentina, Chile, and Bolivia. The bark of Quebracho (Cortex Quebracho) is very dense (quebra hacha—breaks the axe), light brown on the outside, reddish on the inside, and coarsely splintery at the fracture. Quebracho contains a number of alkaloids: quebrachine C₂₁H₂₆O₃N₂, aspidospermine C₂₂H₃₀O₂N₂, aspidozamine C₂₂H₂₈O₂N₂, hypo-quebrachine C₂₀H₂₆O₂N₂, aspidospermatine C₂₂H₂₈O₂N₂, and others. Among them, the most active is quebrachine, which some researchers (Fourneau, Cushny) identify with yohimbine (see). Quebracho alkaloids cause nausea, accompanied by increased secretion of bronchial mucus, stimulation of the respiratory center, and dilation of blood vessels. In cases of poisoning, death occurs from respiratory paralysis. It is used in therapy for chronic bronchitis and pulmonary emphysema in the form of a decoction (10.0:200.0) — one tablespoon three times a day, a fluid extract (Extr. fluid. Quebracho) — 30-60 drops per dose, and a tincture (1:5) — 1-2 teaspoons per dose. QUECKENSTEDT SIGN (Queckenstedt), consists of a disturbance in the fluctuations of cerebrospinal fluid pressure during compression of the jugular veins in the neck. Under normal conditions, compression of these veins causes an increase in intracranial pressure due to the engorgement of cerebral vessels, which is then transmitted to the entire column of cerebrospinal fluid. The fluid pressure (when measured with a special apparatus) begins to rise just 1 second after compression of the veins and increases very rapidly, exceeding the initial pressure by 100-150 mm of water column. After the compression of the veins ceases, the fluid pressure returns almost instantly to the initial level. In the case of narrowing or interruption of communication at any point in the spinal canal, compression of the neck veins causes a very slow increase in fluid pressure below the site of the interruption and an equally slow decrease after the compression ceases, or does not change the pressure at all. This is a positive Queckenstedt sign. A positive Queckenstedt sign is observed in various processes leading to limited narrowing or closure of the lumen of the spinal canal: in tumors of the spinal cord, more often extramedullary, processes in the vertebrae leading to compression of the spinal cord (caries, tumors), inflammatory processes in the meninges and spinal cord accompanied by significant tissue edema or adhesion of the meninges, etc.

and the symphysis in the direction toward the tubercle on the medial condyle of the femur, to which the adductor magnus attaches (tuberculum adductorium) (see figure). This line is used when ligating the femoral artery in its various sections below the Poupart ligament. When ligating the femoral artery under the arch, the Quénu line accurately indicates the path of the artery. After dissecting the two layers of the cribriform fascia and the superficial layer of the iliopectineal fascia, one reaches the artery.

The femoral vein remains slightly medial to the Quénu line. This line also serves as an accurate indicator for locating the femoral artery in the Scarpa triangle.

Only when ligating the femoral artery in the Hunter canal does the projection of the artery not coincide with the projection of the Quénu line. In the latter case, one is guided by the edge of the tendon of the adductor magnus muscle.