Anaesthesia and neuromuscular disorders: what a neurologist needs to know

Management of Chronic Neuromuscular Respiratory Failure in the Intensive Care Unit

In this seminar we describe the critical care management of patients with chronic neuromuscular diseases (cNMD). Determination of the acuity of the critical illness and trajectory of illness in the setting of cNMD is necessary to guide decision making. Systemic complications of critical illness, cardiac support needs, and peri-intubation considerations may be affected by underlying diagnosis. Mechanical ventilatory support, whether noninvasive or invasive, requires redefinition of the goals of ventilation on a patient-by-patient basis. Mode and approach to invasive ventilation and liberation to noninvasive ventilation versus tracheostomy have limited evidence, but potential clinical approaches are reviewed.

Sugammadex for our little ones: a brief narrative review

Sugammadex, the first noncompetitive antagonist developed for the reversal of neuromuscular blockade (NMB), is one of the few drugs that has revolutionized anesthetic practice. However, the use of sugammadex for children between the ages of 2 and 17 years has only recently been approved and is currently not approved for children under the age of 2 years. Although the precision and reliability of reversal of NMB with sugammadex are of great benefit in pediatric anesthesia, several important questions remain regarding its use in our youngest patients. In this brief narrative review, we aim to provide an overview of the key considerations and potential challenges that anesthesiologists often face when using sugammadex in pediatric patients.

Anesthetic Approach for a Pediatric Patient With Facioscapulohumeral Muscular Dystrophy

Facioscapulohumeral muscular dystrophy (FSHD) belongs to the group of rare diseases known as muscular dystrophies. Patients with muscular dystrophies face a heightened risk of intraoperative complications, including severe hyperkalemia and acute rhabdomyolysis. This case report outlines the anesthetic approach employed for a pediatric patient diagnosed with FSHD undergoing a planned exploratory tympanotomy. To the best of our knowledge, it is the first documented case in the literature detailing pediatric general anesthesia in a patient with FSHD, with the additional use of neuromuscular blockade reversal with sugammadex.

[Trigger-free anesthesia : Indications and safe application]

The safe anesthesiological care of patients with neuromuscular diseases poses a particular challenge for anesthetists. Only a small group of muscle diseases and syndromes are associated with an increased risk of malignant hyperthermia and therefore require trigger-free anesthetic procedures avoiding volatile anesthetics and succinylcholine. These diseases are frequently associated with mutations in the RYR1, CACNA1S or STAC-3 genes. In other neuromuscular diseases, anesthetic-induced rhabdomyolysis can occur. Therefore, volatile anesthetics should be avoided in these patients in addition to the contraindication for succinylcholine. In other neuromuscular diseases the risk of a propofol infusion syndrome or myotonic crises can be elevated or the duration of the effect of non-depolarizing muscle relaxants can be changed in an incalculable way. In every case an individual anesthetic aproach including the avoidance of potential pharmacological or non-pharmacological triggers is essential for the safety of the patients.

Acute myotonic reaction during succinylcholine anaesthesia

A 21-year-old woman developed an acute myotonic reaction while undergoing anaesthesia using succinylcholine. Examination later showed she had shoulder, neck and calf hypertrophy, bilateral symmetrical ptosis and eyelid, handgrip and percussion myotonia. Peripheral neurophysiology studies identified significant, continuous myotonic discharges in both upper and lower limbs. Genetic analysis identified a c.3917G>A (p.Gly1306Glu) mutation in the SCN4A gene, confirming a diagnosis of sodium channel myotonia. Succinylcholine and other depolarising agents can precipitate life-threatening acute myotonic reactions when given to patients with myotonia. Patients with neuromuscular disorders are at an increased risk of perioperative anaesthetic complications. We report a woman who developed an acute myotonic reaction whilst undergoing anaesthesia, in the context of an unrecognised myotonic disorder. We then discuss an approach to the diagnosis of myotonic disorders.

A Review on the Anesthetic Management of Patients with Neuromuscular Diseases

Context: Neuromuscular diseases (NMDs) are regarded as a clinically and genetically heterogeneous group of diseases characterized by weakening muscle strength and dystrophic changes in the muscle. Due to the nature of these diseases, it can be challenging for anesthesiologists to provide appropriate pain medications, symptom management, and other necessary techniques that are implemented to anesthetize the patient properly. Evidence Acquisition: This study was based on the available literature and the authors’ experience. The current study aimed to review the available anesthesia for patients suffering from NMDs. The search process resulted in the detection of relevant articles using valid keywords on electronic databases, including Embase, PubMed, Scopus, Web of Science, and Cochrane Library. Subsequently, 24 articles published between 2009 to 2022 were identified as eligible for this review. Results: When anesthetizing a patient with NMD, special attention should be paid to preoperative evaluation, medical-history taking, risk of difficult intubation or cardiac incidents, respiratory insufficiency, and frequent pulmonary infections. It is also necessary to keep in mind that these patients are at risk of prolonged paralysis, hyperkalemia, rigidity, malignant hyperthermia, cardiac arrest, rhabdomyolysis, or even death. Conclusions: Problems of anesthesia in patients with NMDs arise from the nature of the condition itself and the interaction of anesthetics and muscle relaxants with anticholinesterase drugs used in therapy. Each patient’s individual risk should be assessed before anesthesia. Therefore, it is important (and even necessary before major surgery) to perform a thorough preoperative examination to not only determine perioperative risk but also to ensure optimal perioperative follow-up.

Mapping the current evidence on the anesthetic management of adult patients with neuromuscular disorders-a scoping review

PURPOSE

Patients with neuromuscular disorders (NMDs) are at increased risk of perioperative complications. The objective of this scoping review was to examine emerging evidence from published studies, case reports, and review articles on anesthetic management of patients with NMDs, following the methodological frame for scoping reviews.

SOURCES

We searched PubMed and EMBASE for articles published between 1 January 2000 and 14 July 2021.

PRINCIPAL FINDINGS

Three prospective and 21 retrospective studies on altered pharmacokinetics and pharmacodynamics of neuromuscular blocking agents (NMBA) in NMD patients were included. Furthermore, 168 case reports/series reporting 212 anesthetics in 197 patients were included. These studies showed that preanesthetic neuromuscular monitoring can be used for precise NMBA dosing in myasthenia gravis patients. Sugammadex was associated with fewer postoperative myasthenic crises. Perioperative complications were not associated with specific anesthetic agents. Case reports/series showed that in 32% (67/212) of anesthetics, at least one complication was reported. Unexpected intensive care unit admission was a frequently reported complication. Patients with a complicated disease course may have had a higher use of succinylcholine (unadjusted relative risk, 0.13; 95% confidence interval [CI], 0.20 to 0.86) and volatile anesthetics (adjusted odds ratio [OR], 0.38; 95% CI, 0.20 to 0.73; P = 0.004).

CONCLUSION

Evidence on the anesthetic management and perioperative complications of patients with NMDs is mainly based on small retrospective studies and case reports. Further clinical trials or large retrospective studies are required to investigate the choice of safe anesthetic agents. Main areas of interest are the potential benefits of neuromuscular monitoring and sugammadex and the risks possibly associated with volatile anesthetics and succinylcholine.

Drugs That Induce or Cause Deterioration of Myasthenia Gravis: An Update

Myasthenia gravis (MG) is an autoimmune neuromuscular disorder which is characterized by presence of antibodies against acetylcholine receptors (AChRs) or other proteins of the postsynaptic membrane resulting in damage to postsynaptic membrane, decreased number of AChRs or blocking of the receptors by autoantibodies. A number of drugs such as immune checkpoint inhibitors, penicillamine, tyrosine kinase inhibitors and interferons may induce de novo MG by altering the immune homeostasis mechanisms which prevent emergence of autoimmune diseases such as MG. Other drugs, especially certain antibiotics, antiarrhythmics, anesthetics and neuromuscular blockers, have deleterious effects on neuromuscular transmission, resulting in increased weakness in MG or MG-like symptoms in patients who do not have MG, with the latter usually being under medical circumstances such as kidney failure. This review summarizes the drugs which can cause de novo MG, MG exacerbation or MG-like symptoms in nonmyasthenic patients.