Neuromuscular blockade cardiovascular effects

Lefebvre HP, Cardona A, Toutain PL et al. (1992) A simple method for the quantitative evaluation of neuromuscular blockade in mice. J Pharm Toxicol Meth 27 129-133 Vizi ES, Tuba Z, Maho S et al. (2003) A new short-acting nondepolarizing muscle relaxant (SZ1677) without cardiovascular side effects. Acta Anaesthesiol Scand 47 291-300... 

MODIFICATION OF THE METHOD Clutton et al. (1992) studied the autonomic and cardiovascular effects of neuromuscular blockade antagonism in the dog. Neuromuscular blockade was antagonized with various anticholinesterase-antimuscarinic drug combinations including atropine, neostigmine and glycopyrrolate. 

Vecuronium is a synthetic steroid derivative that produces full neuromuscular blockade about 3 minutes after a dose of 0.1 mg/kg. After this dose, its diuration of action is 20-30 minutes. It has no cardiovascular side-effects and does not cause histamine release. 

The onset time for complete neuromuscular blockade is similar to that of D-tubocurarine and other non-depolarizing agents, namely 2-4 minutes. However, this is to some extent dose-dependent, and because of the relative lack of cardiovascular effects and histamine release, pancuronium can safely be given in higher dosages, thus producing good intubation conditions within 2 minutes. The dose of D-tubocurarine required to achieve similar... 

Pipecuronium bromide, a long-acting neuromuscular blocking agent, exhibits minimal cardiovascular effects. Like pancuronium and vecuronium, pipecuronium undergoes some hydrolysis but is excreted primarily unchanged in the urine with very small amounts in the bile. Pipecuronium may be used in patients with coronary artery disease, but neuromuscular blockade is prolonged in patients with renal failure. 

Tobacco smoke includes 4000 chemical species with varying potential which cause adverse effects. Nicotine is stimulating to the autonomic nervous system ganglia and neuromuscular junction. The most prominent effects relate to stimulation of the adrenal medulla, central nervous system (CNS), cardiovascular system (release of catecholamines), gastrointestinal tract (parasympathetic stimulation), salivary and bronchial glands, and the medullary vomiting center. There is subsequent blockade of autonomic ganglia and the neuromuscular junction transmission, inhibition of catecholamine release from the adrenal medulla, and CNS depression. 

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