What are Muscle Relaxants?

N2 choline receptor blockers, also called skeletal muscular relaxants, can selectively act on N2 receptors on motor nerve endplate membranes, blocking nerve impulses from transmitting to skeletal muscle. , Resulting in muscle relaxation.

Muscle relaxant

N2 choline receptor blockers, also called skeletal muscular relaxants, can selectively act on N2 receptors on motor nerve endplate membranes, blocking nerve impulses from transmitting to skeletal muscle. , Resulting in muscle relaxation.

Chinese name

N2 Choline Receptor Blockers

Foreign name

skeletal muscular relaxants

Classification

Depolarized and non-depolarized

Features

Relax skeletal muscle

Adverse reactions

Decreased blood pressure, bradycardia, and heart rhythm disturbances

Clinical application

Gain muscle relaxation to meet surgical requirements

According to their different mechanisms, they can be divided into two categories: depolarizing muscular relaxants and non-depolarizing muscular relaxants.

The use of muscle relaxants after clinical anesthesia changes the muscle relaxation achieved by deepening general anesthesia to meet the requirements of surgery. Therefore, muscle relaxants have become an important adjuvant for general anesthesia. In addition, muscle relaxants can be used for mechanically ventilated patients.

(1) All muscle relaxants have different degrees of respiratory depression. After taking the medicine, you must observe the breathing closely and strengthen the lithium in the breathing tube. Muscle relaxants should only be used if adequate oxygenation and effective ventilation are ensured (eg, endotracheal intubation).

(2) Appropriate muscle relaxants should be selected according to the condition (such as liver and kidney function), type of surgery and time. Avoid excessive drug dosage and accumulation after repeated administration, so that the patient can recover muscle tension early after surgery. Individual muscle relaxants vary widely. For the application of lithium relaxants, it is necessary to use a muscle relaxant monitor to monitor the degree of muscle relaxants.

(3) Muscle relaxant is a supplementary drug for general anesthesia. It has no anesthetic and analgesic effects. Muscle relaxants can only be used while maintaining a certain general anesthesia depth.

(4) When two types of muscle relaxants are used in combination, clinically, short-acting depolarizing muscle relaxants are used first, and then long-acting non-depolarizing muscle relaxants are used to maintain muscle relaxation. Simultaneous mixing or reversing applications can result in enhanced and prolonged neuromuscular block.

(5) Patients who have applied muscle relaxants must be closely observed after the operation. After the ventilation, various protective reflexes, and muscle tension have returned to normal, they have recovered, and the residual muscle relaxant effect can be removed before returning to the ward.

(6) Phase block does not advocate antagonizing phase block. Medical | Science Education Network collects whole lithium mainly by maintaining artificial ventilation for its natural recovery, while inputting fresh whole blood or plasma, supplementing plasma cholinesterase preparations, and paying attention to correcting electrolyte and acid-base imbalances.

1. Inhalation general anesthesia: when inhaled anesthetics halothane, enflurane, isoflurane, sevoflurane and desflurane are used in combination with non-depolarizing muscle relaxants, the amount of non-depolarizing muscle relaxants is reduced and the effect is reduced. Prolonged and dose-effect relationship exists. The order of inhalation anesthetics to enhance the effect of non-depolarizing muscle relaxants is: the strongest is isoflurane, enflurane and desflurane, the second is halothane, and the weakest is nitrous oxide. Inhalation anesthetics enhance the effect of long-acting non-depolarizing muscle relaxants (halothane can reduce the dose of muscle relaxants by 1/3 and enflurane can reduce by 1/2 to 1/3). Inhalation anesthetics have a weaker effect on the medium-acting, non-depolarizing muscle relaxants vecuronium and atracurium, reducing the dose of muscle relaxants by only a quarter. The interaction between succinylcholine and isoflurane is stronger than that of halothane. Enflurane and isoflurane can promote the early evolution of succincholine into phase II block.

2. Local anesthetics and antiarrhythmic drugs: local anesthetics can enhance muscle relaxant effects, such as procaine to enhance the effects of chlorpyridine and succinylcholine, and lidocaine and bupivacaine to enhance the effects of acuronium . Quinidine, which is used for antiarrhythmia, has a local anesthetic effect, so it has a synergistic effect on non-depolarizing muscle relaxants and depolarizing muscle relaxants, which can enhance the strength and time-effect of muscle relaxants. -receptor blockers and calcium channel blockers can also enhance the effects of non-depolarizing muscle relaxants.

3. Antibiotics Many antibiotics can enhance the effect of muscle relaxants, but the enhancement mechanism varies from drug to drug. Among aminoglycoside antibiotics, neomycin and streptomycin have the strongest inhibitory effect on neuromuscular conduction. Both gentamicin and amikacin can enhance depolarization and non-depolarization muscle relaxants. effect. Its enhanced effect has dual effects before and after the joint. Polymyxin has the strongest effect on neural junctions. Lincomycin and clindamycin enhance non-depolarizing muscle relaxants, but do not enhance depolarizing muscle relaxants. Penicillin and vanillin have no obvious clinical dose range. Enhance the effect of muscle relaxants.

4. Anticonvulsants and psychiatric drugs have shown that patients treated with phenytoin sodium have an antagonistic effect on pancuronium bromide, chloromethicyl poison, and vecuronium bromide, but have no antagonistic effects on chlorpyridine and atracurium . In patients with manic depression treated with lithium, the block of pancuronium bromide and succinylcholine increased, but lithium did not enhance the effects of chlorpyrifos and goradomide.