Suxamethonium Pancuronium

In other studies diazepam was found to have no significant effect on the neuromuscular blockade due to alcuronium, atracurium, gaiiamine, pancuronium, suxamethonium " or tubocurarine. " " Lo-razepam and lormetazepam have been reported to have little or no effects on atracurium or vecuronium, and midazolam has been reported to have no eftect on suxamethonium or pancuronium. ... 

It is certain that pancuronium is but the first of a series of steroids of this type There is l or example, need for an agent with its favourable properties but with the brevity ot action of suxamethonium. Achievement of this aim may not be too distant since quaternary derivatives of the alkaloid conessine, possessing (in cats at least) the required characteristics have recently been described [75], and dacuronium bromide is now under intensive study by the team responsible for the development of pancuronium. 

A few cases of potentiation of the neuromuscular blocking effects of suxamethonium and pancuronium were reported about 30 years ago (660,661) and have been reviewed (662). 

In 113 patients undergoing general anesthesia, intravenous midazolam 15 mg slowed recovery of the twitch height after vecuronium and atracurium compared with diazepam. The recovery index was not altered (162). However, in another study in 20 patients, midazolam 0.3 mg/kg did not affect the duration of blockade, recovery time, intensity of fasciculations, or adequacy of relaxation for tracheal intubation produced by suxamethonium 1 mg/kg, nor the duration of blockade and adequacy of relaxation for tracheal intubation produced by pancuronium 0.025 mg/kg in incremental doses until 99% depression of muscle-twitch tension was obtained (161). Furthermore, in 60 patients undergoing maintenance anesthesia randomly assigned to one of six regimens (etomidate, fentanyl, midazolam, propofol, thiopental plus nitrous oxide, or isoflurane plus nitrous oxide), midazolam did not alter rocuronium dosage requirements (165). 

Driessen JJ, Vree TB, van Egmond J, Booij LH, Crul JF. In vitro interaction of diazepam and oxazepam with pancuronium and suxamethonium. Br J Anaesth 1984 56(10) 1131-8. 

Alcuronium Chloride Benserazide Bethanidine Bretylium Tosylate Carbachol Debrisoquine Dibromopropamidine Dihydrostreptomycin Guanethidine Guanoxan Hexylcaine Homatropine Hydroxystilbamidine Hyoscine Kanamycin Mepenzolate Bromide Metformin Obidoxime Chloride Pancuronium Bromide Pentamidine Pentapiperide Propamidine Pyrithidium Bromide Suxamethonium Chloride Suxethonium Bromide Thiamine... 

The aminoglycosides have a curare-like action, which can be antagonized by calcium ions and acetylcholinesterase inhibitors (8). In patients who require general anesthesia, the effect of muscle relaxants, such as o-tubocurarine, pancuronium, and suxamethonium, can be potentiated by aminoglycosides (183). 

Hemodilution (for example the replacement of 1 liter of blood by dextran-40) increased the potencies and prolonged the actions of suxamethonium, pancuronium, D-tubocurarine, and vecuronium (SEDA-17, 151) (105). To avoid this, blood collection should be carried out before the administration of anesthetic drugs. 

Pancuronium is reported to inhibit plasma cholinesterase (2) and this may be partly why the action of suxamethonium, given after a small dose of pancuronium, is prolonged. It also weakly inhibits acetylchohnesterase. 

The matemofetal transfer or rocuronium, as indicated by a fetaFmatemal plasma concentration ratio of 0.16, is between that of vecuronium and pancuronium (32). When rocuronium was used for cesarean section, no adverse effects on the fetus were observed (32). With regard to the duration of rocuronium-induced paralysis and the relatively high incidence of failed intubations in obstetric patients, however, it was agreed that rocuronium should be considered for rapid-sequence intubation for cesarean section only if suxamethonium is contraindicated (33-35). 

Tachycardia and a rise in blood pressure are occasionally seen. Other supraventricular and ventricular dysrhythmias are much less common. Ventricular fibrillation associated with suxamethonium is usually the result of hyperkalemia, but has also been reported in hypercalcemia (22) and is often seen in the course of malignant hyperthermia. Atropine, especially when given intravenously just before suxamethonium, is the most effective agent for the prevention of dysrhythmias. Hexafluorenium, D-tubocurarine, pancuronium, and other non-depolarizer blockers have also been reported as being effective in prevention. Severe hypotension can occur in patients with anaphylactoid reactions. 

Bowen DJ, McGrand JC, Palmer RJ. Intraocular pressures after suxamethonium and endotracheal intubation in patients pretreated with pancuronium. Br J Anaesth 1976 48(12) 1201-5. 

Skeletal muscle relaxants fall into three major categories those that reduce spasticity, those that cause neuromuscular blockade and those that work at the cellular level. Spasmolytic agents (e.g. metho-carbamol, guaifenesin) act centrally whereas neuromuscular blockers (e.g. succinylcholine (suxamethonium), pancuronium, atracurium) act at the neuromuscular end plate to produce muscular relaxation. Dantrolene falls into the third category and acts within the muscle cell itself to produce relaxation. 

Pancuronium and vecuronium (Fig. 11.39) were designed to act like tubocurarine, but with a steroid nucleus acting as the spacer . The distance between the quaternary nitrogens is 1.1 nm as compared to 1.4 nm in tubocurarine. Acyl groups were also added to introduce two acetylcholine skeletons into the molecule in order to improve affinity for the receptor sites. These compounds have a rapid onset of action and do not affect blood pressure. However, they are not as rapid in onset as suxamethonium and also last too long (45 minutes). 

A myasthenic patient developed very prolonged respiratory depression very shortly after being given thiotepa intraperitoneally, following the use of pancuronium. Thiotepa has also been shown to increase the duration of suxamethonium (succinyicholine) neuromuscular blockade in dogs. However, an in vitro study showed that thiotepa was a poor inhibitor of plasma cholinesterase. See also (d) below. 

Bambuterol can prolong the recovery time from neuromuscular blockade with suxamethonium (succinylcholine) or mivacuiium. A case report describes modestly enhanced neuromuscular blockade when pancuronium or vecuronium were given after intravenous salbutamoL... 

An isoiated case report describes potentiation of tubocurarine and pancuronium by orai verapamii. However, long-term oral nifedipine did not aiter vecuronium or atracurium effects, and iong-term therapy with various caicium-channel blockers did not interact with rocuronium. Caicium-channei blockers do not increase the piasma potassium rise due to suxamethonium (succi-nyichoiine). 

A report describes respiratory insufficiency during the recovery period following snidery, which was attributed to the use of chloroquine diorotate. An isolated report describes recurarisation and dyspnoea in a patient given intravenous quinine after recovering from neuromuscular blockade with suxamethonium (succinylcholine) and pancuronium. 

The concurrent use of neuromuscular blockers and lithium is normally safe and uneventful, but four patients taking lithium experienced prolonged blockade and respiratory difficulties after receiving standard doses of pancuronium and/or suxamethonium (succinylcholine). 

A manic depressive woman taking lithium carbonate with a lithium level of 1.2 mmol/L, underwent surgery and was given thiopental, 310 mg of suxamethonium (succinylcholine) over a period of 2 hours, and 500 mierograms of pancuronium. Prolonged neuromuscular blockade with apnoea occurred. ... 

Three other patients taking lithium experienced enhanced neuromuscular blockade when given pancuronium alone, with suxamethonium, or both. The authors of one of these reports say that. . We have seen po-... 

The effects of cisatracurium, mivacurium, pancuronium, rocuro-nium, tubocurarine, vecuronium, and probably other competitive neuromuscular blockers can be increased and prolonged by magnesium sulfate given parenterally. There is some evidence that magnesium may interact similarly with suxamethonium (succinylcholine), but also evidence from well-controlled trials that it does not. 

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