Pipecuronium Bromide
Indications
Used as a muscle relaxant during anesthesia and surgical procedures.
Pharmacology
Pipecuronium is a nondepolarizing neuromuscular blocking agent. Neuromuscular blocking agents produce skeletal muscle paralysis by blocking neural transmission at the myoneural junction. The paralysis is selective initially and usually appears in the following muscles consecutively: levator muscles of eyelids, muscles of mastication, limb muscles, abdominal muscles, muscles of the glottis, and finally, the intercostal muscles and the diaphragm. Neuromuscular blocking agents have no clinically significant effect on consciousness or the pain threshold.
Nondepolarizing neuromuscular blocking agents inhibit neuromuscular transmission by competing with acetylcholine for the cholinergic receptors of the motor end plate, thereby reducing the response of the end plate to acetylcholine. This type of neuromuscular block is usually antagonized by anticholinesterase agents.
Dosage And Administration
Intravenous (Adult)-
- Initial dose: 80-100 mcg/kg.
- Subsequent doses: 10-20 mcg/kg.
- Initial dose following suxamethonium admin or in patients at high risk: 50-60 mcg/kg.
- Initial dose for caesarean section: 35 mcg/kg.
Interaction
Actions antagonised by cholinesterases and long term carbamazepine, phenytoin or corticosteroids usage. Enhanced block when used with drugs that have neuromuscular blocking activity such as lidocaine, quinidine, verapamil and aminoglycosides.
Contraindications
Hypersensitivity.
Side Effects
Transient hypotension, bradycardia, reduced cardiac output.
Pregnancy And Lactation
Pregnancy Category C. Either studies in animals have revealed adverse effects on the foetus (teratogenic or embryocidal or other) and there are no controlled studies in women or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the foetus.
Precautions And Warnings
Pulmonary disease, respiratory insufficiency, asthma, neuromuscular disease, dehydration, severely ill patients, hepatic or renal impairment. Doses in obese patients should be based on patient's ideal body weight. Pregnancy, lactation.
Overdose Effects
Prolonged apnoea due to paralysis of the intercostal muscles and diaphragm, with CV collapse and effects of histamine release.
Therapeutic Class
Non depolarizing muscle relaxants.