Lithium carbonate and neuromuscular blocking agents

Facts and myths about the use of lithium for bipolar disorder in routine clinical practice: an expert consensus paper

BACKGROUND

Bipolar disorder is one of the most burdensome severe mental disorders, characterized by high levels of personal and social disability. Patients often need an integrated pharmacological and non-pharmacological approach. Lithium is one of the most effective treatments available not only in psychiatry, but in the whole medicine, and its clinical efficacy is superior to that of other mood stabilizers. However, a declining trend on lithium prescriptions has been observed worldwide in the last 20 years, supporting the notion that lithium is a 'forgotten drug' and highlighting that the majority of patients with bipolar disorder are missing out the best available pharmacological option. Based on such premises, a narrative review has been carried out on the most common "misconceptions" and "stereotypes" associated with lithium treatment; we also provide a list of "good reasons" for using lithium in ordinary clinical practice to overcome those false myths.

MAIN TEXT

A narrative search of the available literature has been performed entering the following keywords: "bipolar disorder", "lithium", "myth", "mythology", "pharmacological treatment", and "misunderstanding". The most common false myths have been critically revised and the following statements have been proposed: (1) Lithium should represent the first choice for the treatment of patients with bipolar disorder; (2) lithium treatment is effective in different patients' groups suffering from bipolar disorder; (3) Drug-drug interaction risk can be easily managed during lithium treatment; (4) The optimal management of lithium treatment includes periodical laboratory tests; (5) Slow-release lithium formulation has advantages compared to immediate release formulation; (6) Lithium treatment has antisuicidal properties; (7) Lithium can be carefully managed during pregnancy.

CONCLUSIONS

In recent years, a discrepancy between evidence-based recommendations and clinical practice in using lithium treatment for patients with bipolar disorder has been highlighted. It is time to disseminate clear and unbiased information on the clinical efficacy, effectiveness, tolerability and easiness to use of lithium treatment in patients with bipolar disorder. It is necessary to reinvigorate the clinical and academic discussion about the efficacy of lithium, to counteract the decreasing prescription trend of one of the most effective drugs available in the whole medicine.

Patients with psychiatric disease: implications for anesthesiologists

PURPOSE OF REVIEW

Psychiatric illness is common in patients presenting for surgery. Overall health and surgical outcomes are adversely affected by the presence of psychiatric comorbidities.

RECENT FINDINGS

As new treatment modalities become available, their perioperative implications need to be evaluated. These implications include drug-drug interactions, hemodynamic effects, bleeding risk, and factors affecting perioperative exacerbation of the underlying psychiatric illness.

SUMMARY

From our review of the recent literature we continue to support the continuation of psychoactive agents in the perioperative period, taking into consideration the effects these agents have on concomitant drug use in the perioperative period; and the risks of withholding them at a high-stress time.

Potentiation of Rocuronium Bromide by Lithium Carbonate: A Case Report

Lithium carbonate is a medication used for the management of various mental disorders. The present report describes a case of prolongation of rocuronium bromide in a patient concurrently taking lithium carbonate. A 64-year-old woman was scheduled to undergo cystectomy under general anesthesia. The patient took lithium carbonate (600 mg/d) for treatment of bipolar affective disorder. General anesthesia was induced with propofol, fentanyl, remifentanil, and sevoflurane. After loss of consciousness, rocuronium bromide (50 mg) was administered, and the trachea was intubated. Approximately 1 hour after the administration of rocuronium, the degree of residual muscle relaxant was evaluated using a nerve stimulation device. No muscle contraction occurred with train-of-four (TOF) stimulation. Following administration of sugammadex (200 mg) the TOF ratio increased to 95%. The ionic size of lithium is similar to that of sodium; therefore, lithium is transported into the cell with sodium. The resting membrane potential decreases, leading to a reduction in the height of the action potential. Thus, the effect of the remaining lithium may have been superimposed on the rocuronium neuromuscular blockade. Evaluation with a nerve stimulation device in patients taking lithium is crucial before extubation because of the risk of rocuronium potentiation.

Electroconvulsive therapy and its different indications

In spite of recent developments in the pharmacotherapy of depressive disorders, the delay until clinical improvement can be achieved, and the considerable rate of nonresponse and nonremission, are major problems which remain unresolved. Electroconvulsive therapy (ECT) is a nonpharmacologic biological treatment which has been proven to be a highly effective treatment option, predominantly for depression, but also for schizophrenia and other indications. Though there is a lack of controlled investigations on long-term treatments, ECT can also be used for relapse prevention during maintenance therapies. The safety and tolerability of electroconvulsive treatment have been enhanced by the use of modified stimulation techniques and by progress in modern anesthesia. Thus, today a safe treatment can also be offered to patients with higher somatic risks. ECT still represents an important option, especially in the therapy of treatment-resistant psychiatric disorders after medication treatment failures. Earlier consideration of ECT may reduce the rate of chronic and difficult-to-treat psychiatric disorders.

Psychotropic Drugs and the Perioperative Period: A Proposal for a Guideline in Elective Surgery

Evidence-based guidelines for the perioperative management of psychotropic drugs are lacking. The level of evidence is low and is based on case reports, open trials, and non-systematic reviews. However, the interactions and effects mentioned indicate that patients who use psychotropics and require surgery have an enhanced perioperative risk. A group of clinicians from several clinical disciplines determined which risks should be considered in an integrated preoperative assessment, as well as how psychotropics might interfere with these risks. The risks that should be considered in the perioperative period are the extent of the surgery, the patient's physical state, anesthesia, the direct and indirect (Phase I and II) effects of psychotropics, risk of withdrawal symptoms, and risk of psychiatric recurrence or relapse. Because of new drug developments, the risk of interactions increases. The literature has not provided articles that systematically address these risks. On the basis of a systematic analysis of the available literature guided by the formulated perioperative risks, a proposal for the perioperative management of psychotropics was formulated. Patients who use lithium, monoamine oxidase inhibitors, tricyclics, and clozepine have serious drug-drug interactions, with increased physical risks, including withdrawal, and therefore qualify for American Society of Anesthesiologists (ASA) Classification 3. From the perspective of the physical risk, they require discontinuation. However, from the perspective of the risk of withdrawal and psychiatric relapse and recurrence, these patients deserve intensive, integrated anesthetic/psychiatric management. For patients on selective serotonin reuptake inhibitors (SSRIs) who are mentally and physical stable (ASA Classification 2), the risk of withdrawal seems to justify their continuation. Yet, patients on SSRIs with higher physical or psychiatric risks should be seen in consultation. Both the physical and psychiatric risks of patients who use antipsychotics and other antidepressants should be regarded as enhanced. From a physical perspective, they qualify for ASA Classification 2. From the perspective of withdrawal and psychiatric recurrence or relapse, they should be seen by (their) psychiatrists. Preoperative assessment clinics offer the opportunity to assess and evaluate these risks in order to deliver patient-tailored integrated care. Authors propose a model for quality management.

Interactions between psychotropics, anaesthetics and electroconvulsive therapy: implications for drug choice and patient management

Despite many predictions that electroconvulsive therapy (ECT) would be replaced by pharmacotherapy, ECT has remained an invaluable adjunct in the management of severe psychiatric disease. Both pharmacotherapy and ECT continue to be used extensively, and will frequently be administered concurrently. The majority of patients requiring ECT will need anaesthesia; therefore, interactions could conceivably occur between the psychotropic drugs, ECT and the anaesthetic agents utilised. In managing an anaesthetic for ECT the effects of the anaesthetic agents and other medications on seizure intensity are important determinants influencing outcome. With regard to the antidepressants, tricyclic antidepressants (TCAs) and ECT can be combined safely and beneficially. More care is required when ECT is administered in the setting of a monoamine oxidase inhibitor (MAOI), especially the older irreversible varieties and in patients recently placed on MAOI therapy. Of the anticonvulsants and mood stabilisers, lithium and ECT given concurrently add significant risk of delirium and/or organic syndromes developing. Possible concerns with valproate, carbamazepine, lamotrigine, gabapentin and topiramate are that they may inhibit seizure activity. Additionally, carbamazepine may prolong the action of suxamethonium (succinylcholine). The combination of antipsychotics and ECT is well tolerated, and may in fact be beneficial. As regards the anxiolytics, benzodiazepines have anticonvulsant properties that might interfere with the therapeutic efficacy of ECT. CNS stimulants on the other hand may prolong seizures as well as produce dysrhythmias and elevate blood pressure. Calcium channel antagonists should be used with great care to avoid significant cardiovascular depression. The anaesthesiologist should therefore remain vigilant at all times, as untoward responses during ECT might occur suddenly due to interactions between psychotropics, anaesthetic agents and/or ECT.

Preoperative assessment of the elderly patient

Organ system functional reserve variability increases progressively with age. In elderly patients, cardiopulmonary, central nervous system, and metabolic functional reserve seem to be the most important predictors of the ability to undergo surgery. Directed testing for the assessment of organ system functional reserve and identification of organs at risk, rather than the diagnosis of disease itself, is the primary goal of preoperative evaluation prior to surgery and is essential to the formulation of an effective anesthetic plan. The risks of adverse drug interaction, already high in the elderly, make a thorough review of the indications and dosage of perioperative medication an important part of the preoperative assessment process.

Anesthesia and mental illness

Although drug interaction probably remains the most potentially serious problem, current evidence suggests that psychiatric medication need not be discontinued prior to anesthesia and surgery, discontinuation of medication may constitute its own hazards. Most interactions can be predicted and appropriate precautions taken, the use of meperidine is now absolutely contraindicated for patients receiving MAOI's.

Adverse reactions and interactions of the neuromuscular blocking drugs

The adverse reactions seen following administration of neuromuscular blocking agents are mainly cardiovascular. Due to the lack of specificity for the nicotinic receptor at the neuromuscular junction, these agents may interact with receptors in autonomic ganglia and muscarinic receptors in the heart. Furthermore, muscle relaxants may have histamine-releasing properties. The cardiovascular effects vary with potency and specificity of the drug, depending mainly on the chemical structure. Pancuronium, fazadinium and especially gallamonium block cardiac muscarinic receptors, and tachycardia may be seen. Atracurium, metocurine and in particular d-tubocurarine have histamine-releasing properties and may cause flushing, hypotension and tachycardia. Vecuronium has no effect on the cardiovascular system. The effect of succinylcholine on heart rate differs between children, where bradycardia is seen, and adults in whom tachycardia may follow. However, bradycardia may occur in adults following a single dose. Succinylcholine increases plasma potassium, especially in patients with nerve damage, and arrhythmias may be observed. The neuromuscular adverse effects of succinylcholine, such as fasciculations and increased gastric and intraocular pressure, may be prevented by precurarisation. Many drugs interact with neuromuscular blocking agents and there is often a potentiation of the neuromuscular effect. This is of clinical importance in the case of antibiotics, inhalational anaesthetics, lithium and cyclosporin. Difficulty in reversing the block may occur with calcium channel blockers and polymyxin. However, some drugs, such as phenytoin, carbamazepine and lithium, may cause resistance to neuromuscular blocking agents. Furthermore, clinically important interactions exist between individual neuromuscular blocking drugs. Precurarisation with a non-depolarising drug prolongs the onset of succinylcholine, and conversely a prolonged effect of non-depolarising drugs is seen following succinylcholine. The effect of succinylcholine is markedly prolonged if the drug is administered during recovery from pancuronium blockade or following neostigmine for reversal. Succinylcholine is hydrolysed by plasma cholinesterase, and drugs which decrease the activity of this enzyme may produce a prolonged block, i.e. contraceptive pills, cyclophosphamide, echothiopate and organophosphate.

Complications of concurrent lithium and electroconvulsive therapy: a review of clinical material and theoretical considerations

Several anecdotal reports and two retrospective chart reviews have examined complications of concurrent lithium and electroconvulsive treatment. Discussions have generally been contradictory or confusing. This article reviews the literature and particularly emphasizes theoretical considerations and mechanisms, concluding (A) that lithium may act synergistically with neuromuscular blockers, but the effect is not clinically significant, and (B) that repeated electroconvulsive seizures may cause a toxic delirium in patients concurrently taking lithium.

Neuromuscular blockade in the emergency department

This article presents a comprehensive review of neuromuscular blocking agents and their uses in the emergency department. These medicines are divided into two categories: depolarizing relaxants (including succinylcholine and decamethonium) and nondepolarizing relaxants (including d-tubocurarine, pancuronium, atracurium, and vecuronium). Also reviewed are pharmaco-kinetics, toxicity, and principal applications of these important agents.

The effect of lithium chloride on tumour appearance and survival of melanoma-bearing mice

The possible effect of lithium chloride, a compound which reduces the incidence of infection in cancer patients, was investigated on murine melanoma. C57 BL syngeneic mice were inoculated i.p. with B16 melanoma cells. The animals were divided into 4 groups, receiving daily i.p. treatment with saline--group 1, controls; lithium chloride--group 2, bleomycin and vinblastine--group 3, and lithium chloride with bleomycin and vinblastine--group 4. Animals in group 4 had a significant delay in tumour appearance, a higher degree of tumour necrosis, and a longer survival rate. In addition a significant reduction of serum lithium concentration was noted in animals of this group in comparison with animals in group 2, treated with lithium chloride alone. There was no lithium-induced leukocytosis.

Effects of prostaglandins and indomethacin on neuromuscular blocking agents

The effects on neuromuscular blockade by d-tubocurarine and succinylcholine of inhibition of prostaglandin biosynthesis by indomethacin and of intra-arterial administration of prostoglandins E2 and F2 alpha, before and after inhibition of prostoglandin biosynthesis, were evaluated in the cat sciatic-tibialis preparation. Non-specific inhibition of prostaglandin biosynthesis by indomethacin 3 mg . kg-1 did not alter latency, maximal blockade or duration of neuromuscular blockade induced by d-tubocurarine or succinylcholine. Prostaglandin E2 antagonized twitch height depression by d-tubocurarine by an average of six per cent before and by 15% after indomethacin, but potentiated the neuromuscular block of succinylcholine by an average of five per cent before and 60% after indomethacin. Prostaglandin F2 alpha antagonized d-tubocurarine neuromuscular block by an average of 10% before and 18% after indomethacin, but potentiated succinylcholine block by an average of four per cent before and 12% after indomethacin. These results suggest that non-specific inhibition of prostaglandin biosynthesis alone does not influence d-tubocurarine or succinylcholine induced neuromuscular blockades. However, both prostaglandin E2 and F2 alpha may induce transmitter release at the neuromuscular junction that may be enhanced by indomethacin, thus antagonizing the non-depolarizing blockade of d-tubocurarine and potentiating the depolarizing blockade of succinylcholine.