European Neuromuscular Centre consensus statement on anaesthesia in patients with neuromuscular disorders

Anesthetic Considerations for Patients with Hereditary Neuropathy with Liability to Pressure Palsies: A Narrative Review

Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal dominant demyelinating neuropathy characterized by an increased susceptibility to peripheral nerve injury from trauma, compression, or shear forces. Patients with this condition are unique, necessitating distinct considerations for anesthesia and surgical teams. This review describes the etiology, prevalence, clinical presentation, and management of HNPP and presents contemporary evidence and recommendations for optimal care for HNPP patients in the perioperative period. While the incidence of HNPP is reported at 7-16:100,000, this figure may be an underestimation due to underdiagnosis, further complicating medicolegal issues. With the subtle nature of symptoms associated with HNPP, patients with this condition may remain unrecognized during the perioperative period, posing significant risks. Several aspects of caring for this population, including anesthetic choices, intraoperative positioning, and monitoring strategy, may deviate from standard practices. As such, a tailored approach to caring for this unique population, coupled with meticulous preoperative planning, is crucial and requires a multidisciplinary approach.

Special electromyographic features in a child with paramyotonia congenita: A case report and review of literature

BACKGROUND

Paramyotonia congenita (PMC) stands as a rare sodium channelopaty of skeletal muscle, initially identified by Eulenburg. The identification of PMC often relies on electromyography (EMG), a diagnostic technique. The child's needle EMG unveiled trains of myotonic discharges with notably giant amplitudes, alongside irregular wave trains of myotonic discharges. This distinctive observation had not surfaced in earlier studies.

CASE SUMMARY

We report the case of a 3-year-old female child with PMC, who exhibited laryngeal stridor, muffled speech, myotonia from birth. Cold, exposure to cool water, crying, and physical activity exacerbated the myotonia, which was relieved in warmth, yet never normalized. Percussion myotonia was observable in bilateral biceps. Myotonia symptoms remained unchanged after potassium-rich food consumption like bananas. Hyperkalemic periodic paralysis was excluded. Cranial magnetic resonance imaging yielded normal results. Blood potassium remained within normal range, while creatine kinase showed slight elevation. Exome-wide genetic testing pinpointed a heterozygous mutation on chromosome SCN4A: c.3917G>A (p.G1306E). After a six-month mexiletine regimen, symptoms alleviated.

CONCLUSION

In this case revealed the two types of myotonic discharges, and had not been documented in other studies. We underscore two distinctive features: Giant-amplitude potentials and irregular waves.

A clinical approach to diagnosis and management of mitochondrial myopathies

This paper provides an overview of the different types of mitochondrial myopathies (MM), associated phenotypes, genotypes as well as a practical clinical approach towards disease diagnosis, surveillance, and management. nDNA-related MM are more common in pediatric-onset disease whilst mtDNA-related MMs are more frequent in adults. Genotype-phenotype correlation in MM is challenging due to clinical and genetic heterogeneity. The multisystemic nature of many MMs adds to the diagnostic challenge. Diagnostic approaches utilizing genetic sequencing with next generation sequencing approaches such as gene panel, exome and genome sequencing are available. This aids molecular diagnosis, heteroplasmy detection in MM patients and furthers knowledge of known mitochondrial genes. Precise disease diagnosis can end the diagnostic odyssey for patients, avoid unnecessary testing, provide prognosis, facilitate anticipatory management, and enable access to available therapies or clinical trials. Adjunctive tests such as functional and exercise testing could aid surveillance of MM patients. Management requires a multi-disciplinary approach, systemic screening for comorbidities, cofactor supplementation, avoidance of substances that inhibit the respiratory chain and exercise training. This update of the current understanding on MMs provides practical perspectives on current diagnostic and management approaches for this complex group of disorders.

[Rare diseases in anesthesia : Knowledge mining and core points of perioperative anesthesiological care]

Due to refined and new diagnostic possibilities and improved medical care, in the future anesthesiologists will be more frequently confronted with patients suffering from rare diseases. As the physicians providing perioperative care often have little or no experience with the diseases of such patients, the access to high-quality specific literature is essential. In this respect they must be able to assess and classify the quality of the information which is predominantly available online, especially as when evidence-based knowledge is available, it is only available to a very limited extent. Patients with rare diseases mostly present with recurring problem constellations. A systematic assignment to the most important problem areas (airway, circulation, metabolism, etc.) as well as a structured and interdisciplinary approach are decisive for a successful perioperative treatment of these patients. Due to low prevalence, lack of personal experience and lack of evidence-based data, anesthesia in patients with SE is an absolute challenge, especially in time-critical situations.

Identification and Management of Acute Neuromuscular Respiratory Failure in the ICU

Respiratory failure is a common and potentially life-threatening complication of neuromuscular diseases. Prompt recognition and accurate diagnosis of new or worsening chronic neuromuscular disease have important clinical management and prognostic implications. In this article, we present an approach to the acute presentation of undifferentiated neuromuscular respiratory failure in the ICU and guidance for determination and respiratory management of the underlying disorder.

Planning anesthesia of a child with a rare disease: useful tools

Up to 8,000 rare diseases are currently described in the scientific literature. The presence of a rare disease constitutes an additional challenge for the practitioner given its implications on the management of anesthesia. Moreover, it is not possible for an anesthesiologist to know them all especially as the sources of information are scattered. This narrative review aims at proposing pre-anesthetic evaluation clear tools to summarize the individual aspects of a known or suspected rare disease in a patient and to define an adapted anesthetic strategy. It also describes a decision-making process, called « the rare disease reflex », to guide the practitioner to quickly initiate diagnostic investigations in the presence of unusual perioperative clinical signs suggestive of an undiagnosed rare disease.

Assessment of Motor Unit Potentials Duration as the Biomarker of DT-DEC01 Cell Therapy Efficacy in Duchenne Muscular Dystrophy Patients up to 12 Months After Systemic-Intraosseous Administration

Duchenne muscular dystrophy (DMD) is a lethal X-linked disease caused by mutations in the dystrophin gene, leading to muscle degeneration and wasting. Electromyography (EMG) is an objective electrophysiological biomarker of muscle fiber function in muscular dystrophies. A novel, DT-DEC01 therapy, consisting of Dystrophin Expressing Chimeric (DEC) cells created by fusing allogeneic myoblasts from normal donors with autologous myoblasts from DMD-affected patients, was assessed for safety and preliminary efficacy in boys of age 6-15 years old (n = 3). Assessments included EMG testing of selected muscles of upper (deltoideus, biceps brachii) and lower (rectus femoris and gastrocnemius) extremities at the screening visit and at 3, 6, and 12 months following systemic-intraosseous administration of a single low dose of DT-DEC01 therapy (Bioethics Committee approval no. 46/2019). No immunosuppression was administered. Safety of DT-DEC01 was confirmed by the lack of therapy-related Adverse Events or Serious Adverse Events up to 22 months following DT-DEC01 administration. EMG of selected muscles of both, ambulatory and non-ambulatory patients confirmed preliminary efficacy of DT-DEC01 therapy by an increase in motor unit potentials (MUP) duration, amplitudes, and polyphasic MUPs at 12 months. This study confirmed EMG as a reliable and objective biomarker of functional assessment in DMD patients after intraosseous administration of the novel DT-DEC01 therapy.

Diagnosis and management of Becker muscular dystrophy: the French guidelines

Becker muscular dystrophy (BMD) is one of the most frequent among neuromuscular diseases, affecting approximately 1 in 18,000 male births. It is linked to a genetic mutation on the X chromosome. In contrast to Duchenne muscular dystrophy, for which improved care and management have changed the prognosis and life expectancy of patients, few guidelines have been published for management of BMD. Many clinicians are inexperienced in managing the complications of this disease. In France, a committee of experts from a wide range of disciplines met in 2019 to establish recommendations, with the goal of improving care of patients with BMD. Here, we present the tools to provide diagnosis of BMD as quickly as possible and for differential diagnoses. Then, we describe the multidisciplinary approach essential for optimum management of BMD. We give recommendations for the initial assessment and follow-up of the neurological, respiratory, cardiac, and orthopedic consequences of males who present with BMD. Finally, we describe the optimal therapeutic management of these complications. We also provide guidance on cardiac management for female carriers.

Application of Advanced Technologies-Nanotechnology, Genomics Technology, and 3D Printing Technology-In Precision Anesthesia: A Comprehensive Narrative Review

There has been increasing interest and rapid developments in precision medicine, which is a new medical concept and model based on individualized medicine with the joint application of genomics, bioinformatics engineering, and big data science. By applying numerous emerging medical frontier technologies, precision medicine could allow individualized and precise treatment for specific diseases and patients. This article reviews the application and progress of advanced technologies in the anesthesiology field, in which nanotechnology and genomics can provide more personalized anesthesia protocols, while 3D printing can yield more patient-friendly anesthesia supplies and technical training materials to improve the accuracy and efficiency of decision-making in anesthesiology. The objective of this manuscript is to analyze the recent scientific evidence on the application of nanotechnology in anesthesiology. It specifically focuses on nanomedicine, precision medicine, and clinical anesthesia. In addition, it also includes genomics and 3D printing. By studying the current research and advancements in these advanced technologies, this review aims to provide a deeper understanding of the potential impact of these advanced technologies on improving anesthesia techniques, personalized pain management, and advancing precision medicine in the field of anesthesia.

Care Recommendations for the Investigation and Management of Children With Skeletal Muscle Channelopathies

The field of pediatric skeletal muscle channelopathies has seen major new advances in terms of a wider understanding of clinical presentations and new phenotypes. Skeletal muscle channelopathies cause significant disability and even death in some of the newly described phenotypes. Despite this, there are virtually no data on the epidemiology and longitudinal natural history of these conditions or randomized controlled trial evidence of efficacy or tolerability of any treatment in children, and thus best practice care recommendations do not exist. Clinical history, and to a lesser extent examination, is key to eliciting symptoms and signs that indicate a differential diagnosis of muscle channelopathy. Normal routine investigations should not deter one from the diagnosis. Specialist neurophysiologic investigations have an additional role, but their availability should not delay genetic testing. New phenotypes are increasingly likely to be identified by next-generation sequencing panels. Many treatments or interventions for symptomatic patients are available, with anecdotal data to support their benefit, but we lack trial data on efficacy, safety, or superiority. This lack of trial data in turn can lead to hesitancy in prescribing among doctors or in accepting medication by parents. Holistic management addressing work, education, activity, and additional symptoms of pain and fatigue provides significant benefit. Preventable morbidity and sometimes mortality occurs if the diagnosis and therefore treatment is delayed. Advances in genetic sequencing technology and greater access to testing may help to refine recently identified phenotypes, including histology, as more cases are described. Randomized controlled treatment trials are required to inform best practice care recommendations. A holistic approach to management is essential and should not be overlooked. Good quality data on prevalence, health burden, and optimal treatment are urgently needed.

Diagnostics in skeletal muscle channelopathies

INTRODUCTION

Skeletal muscle channelopathies (SMCs) are a heterogenous group of disorders, caused by mutations in skeletal ion channels leading to abnormal muscle excitability, resulting in either delayed muscle relaxation (myotonia) which characterizes non-dystrophic myotonias (NDMs), or membrane transient inactivation, causing episodic weakness, typical of periodic paralyses (PPs).

AREAS COVERED

SMCs include myotonia congenita, paramyotonia congenita, and sodium-channel myotonia among NDMs, and hyper-normokalemic, hypokalemic, or late-onset periodic paralyses among PPs. When suspecting an SMC, a structured diagnostic approach is required. Detailed personal and family history and clinical examination are essential, while neurophysiological tests should confirm myotonia and rule out alternative diagnosis. Moreover, specific electrodiagnostic studies are important to further define the phenotype of de novo cases and drive molecular analyses together with clinical data. Definite diagnosis is achieved through genetic testing, either with Sanger sequencing or multigene next-generation sequencing panel. In still unsolved patients, more advanced techniques, as exome-variant sequencing or whole-genome sequencing, may be considered in expert centers.

EXPERT OPINION

The diagnostic approach to SMC is still mainly based on clinical data; moreover, definite diagnosis is sometimes complicated by the difficulty to establish a proper genotype-phenotype correlation. Lastly, further studies are needed to allow the genetic characterization of unsolved patients.

[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.

Cancer and Myotonic Dystrophy

Myotonic dystrophy (DM) is the most common muscular dystrophy in adults. Dominantly inherited CTG and CCTG repeat expansions in DMPK and CNBP genes cause DM type 1 (DM1) and 2 (DM2), respectively. These genetic defects lead to the abnormal splicing of different mRNA transcripts, which are thought to be responsible for the multiorgan involvement of these diseases. In ours and others' experience, cancer frequency in patients with DM appears to be higher than in the general population or non-DM muscular dystrophy cohorts. There are no specific guidelines regarding malignancy screening in these patients, and the general consensus is that they should undergo the same cancer screening as the general population. Here, we review the main studies that investigated cancer risk (and cancer type) in DM cohorts and those that researched potential molecular mechanisms accounting for DM carcinogenesis. We propose some evaluations to be considered as malignancy screening in patients with DM, and we discuss DM susceptibility to general anesthesia and sedatives, which are often needed for the management of cancer. This review underscores the importance of monitoring the adherence of patients with DM to malignancy screenings and the need to design studies that determine whether they would benefit from a more intensified cancer screening than the general population.

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.