Muscle relaxants are medications decreasing skeletal muscles tone with reduction of motion activity to full immobilization.
The muscle relaxant started its history in 16th century when the South-American Indians are revealed to use for hunting and war the poisoned arrows, poison was curare leading to death because of respiratory muscles paralysis. After investigations of this poison the scientists have found out a great effect of anesthesia that leads to surgery development. This helped to study the mechanism of neuromuscular transmission. Since 1943 the nervously-muscular blockers have known in medicine as muscle relaxants.
Muscle relaxants are medications blocking neuromuscular transmission. They are used for controllable mechanical ventilation of lungs, providing conditions for surgery, especially in surgery on breast and stomach, lowering intracranial hypertension, decrease in consumption of oxygen, reducing of shivering, providing immovability for some diagnostic manipulations, convulsive syndrome relief and in some other cases. Muscle relaxants allow to reduce pain syndrome in patients with muscular spasms. Muscle relaxants use in hernias of intervertebral disks to relieve back muscles spasms.
A significant number of muscle relaxants are applied in the world. It is difficult to imagine the modern surgery without them. Muscle relaxant advantages are in fast reactions, high efficiency and safety of the drug. Muscle relaxants work in low doses on nicotinic receptors as competitive antagonists of acetylcholine. In high doses certain drugs of this group penetrate directly into ionic channels, weakening neuromuscular transmission. To support muscles clonus, the impulses are required, muscle relaxants work so that receptors remain blocked, impulses are not received, muscular fibre are polarized, muscle relaxant is developed. However, it should be noted that the action mechanism of muscle relaxant is not fully clear yet. The clinical researches started by G.Griffith in 1942 are still continued.
Muscle relaxants usually are taken in exceptional cases and under the doctors’ supervision. The doctor will examine you and will indicate a dose and the treatment course, if muscle relaxants are required. The dosage depends on required relaxation level, on body weight and on the patient’s individual tolerance. So it is recommended before the surgery to define sensitivity to the drug by small quantity, injection dose of 0.05 mg/kg.
Administration of 0.1mg/kg leads to relaxation of skeletal muscles without affecting breath function, a dose from 0.2 mg/kg to 1.5 mg/kg leads to full relaxation of abdominal muscles and skeletal muscles and to lowering of spontaneous breath.
Muscle relaxant are used in medicine for providing conditions for intubation of trachea, suppression of independent breathing for artificial lung ventilation procedure, decrease in convulsive syndrome in inefficiency of anticonvulsive drugs, blockade of protective reactions to cold of muscular shivering and muscles hypertone of artificial hypothermia, and muscle relaxant in reposition the fracture fragments and diaplasis of joints.
You should remember that muscle relaxant use is recommended after consultation with the doctor and under his supervision. Discuss with him all contraindications to application as side-effects and successful drug use depends on it. Contraindications include hypersensitivity to suxamethonium chloride. Serious liver disorders, pulmonary edema, expressed hyperthermia, low acetylcholinesterase, hyperpotassemia, neuromuscular diseases and neurologic disorders, muscular rigidity, full-thickness burns, eye damages.
During muscle relaxant use, certain side-effects may be observed: high intracranial pressure, paralysis of skeletal muscles, rise of intraocular pressure, rise of pressure in the stomach cavities, muscle pain, fasciculation, drowsiness, dry mouth, urinary difficulty, and nausea.
