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Query: UMLS:C0020672 (hypothermia)
 17,327 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Freeze fracture replicas of neuromuscular junctions from normal human patients and those with facioscapulohumeral and limb girdle muscular dystrophies, progressive muscular atrophy, and myasthenia gravis were examined by stereoscopic electron microscopy. Endplates from most human patients closely resemble those of normal adult rats fixed by intravascular perfusion. However, endplates from patients with myasthenia gravis have clinically relevant alterations in postsynaptic membrane infrastructure, including decreased number of P-face particles and increased number of E-face particles in the crests of the junctional folds. Other junctional fold crests are narrowed or obliterated and are replaced by incompletely sealed membrane vesicles rich in intramembrane particles. Similar alterations are not produced in rat endplates by immersion fixation, exposure to low pH, brief hypoxia, prolonged or extreme hypothermia, prolonged or high frequency nerve stimulation, or by prolonged nerve quiescence. Rather, the destructive alterations observed in junctional fold membranes in myasthenia gravis endplates are correlated with decreased acetylcholine sensitivity and to removal of endplate acetylcholine receptors by immunologic processes.
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PMID:Freeze fracture studies of human neuromuscular junctions. Membrane alterations observed in myasthenia gravis. 723 Jul 37

Disorders of skeletal muscle and peripheral nervous system are collectively called neuromuscular disorders (NMD). Important for anesthesia is that these disorders show various symptoms and have a high risk during general anesthesia. Especially administration of succinylcholine and volatile anaesthetics may cause problems. Under special circumstances opioids, nondepolarising muscle relaxants and intravenous anaesthetics can interfere with this kind of disorder, too. Complications during and after anaesthesia may result in malignant hyperthermia, malignant hyperthermia-like reactions and primary or secondary changes relating to the underlying NMD. These include cardiac and respiratory problems, dysautonomia as well as hypothermia or hyperthermia. Thus the perioperative management must be determined individually to assure the best possible safety for each patient. Preoperative examination such as ECG, echocardiography, respiratory function test including arterial blood-gas analysis, x-ray of the thorax, neurological status, and extended serum chemistry (such as CK and myoglobin) needs to be done. For premedication no drugs suppressing respiratory function should be administered. Regional anesthesia should be used whenever possible, especially in patients with respiratory and cardiac problems. The dosage of all recommended drugs should be as low as possible. Volatile anaesthetics should not be administered in the majority of NMD and succinylcholine is contraindicated, with the exception of myasthenia gravis. Additionally to the usual intraoperative monitoring, the invasive measurement of blood pressure allows frequent blood-gas analysis. It is obligate to monitor neuromuscular function and body temperature. During recovery special attention should be paid to maintain normal body temperature and electrolytes and acid-base status. The discharge of the patient from the recovery area to the normal ward should be performed only after respiratory function is normalized.
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PMID:[Anesthesia in neuromuscular disorders. Part 1: introduction]. 1186 84

4-aminopyridine (4-AP) is an orphan drug in the United States. It enhances neuronal conduction at synapses and is indicated in the treatment of selected neuromuscular disorders, including multiple sclerosis and myasthenia gravis, among others. Its documented toxicity generally has been limited to central nervous system (CNS) hyperexcitation and gastrointestinal upset. In this case, a 56-year-old man accidentally overdosed on an unknown amount of generic 4-AP. This history was unknown by his family and unavailable to initial providers. Approximately 1 h after ingestion, his son found him diaphoretic, vomiting, and having unintelligible speech. In the ensuing 2-3 h, the patient became moderately hypothermic (32.8 degrees C; 91 degrees F), developed atrial fibrillation with a rapid ventricular response, and had neurological changes that were confused with an acute cerebrovascular accident. After a 36-h stay in the intensive care unit that included mechanical ventilation, cardioversion, passive rewarming, and an extensive medical workup, the patient recovered without sequelae. After extubation he stated that he thought he may have ingested too much 4-AP after rubbing a large amount of it against a sore tooth to take advantage of its local analgesic properties. This case of 4-AP overdose resulting in atrial fibrillation with rapid ventricular response, hypothermia, and acute neurological changes mistaken for an acute cerebrovascular accident is an unusual one. This case shows that overdose of 4-AP can cause or mimic several serious medical conditions, and that a detailed history and physical examination are essential for uncovering unusual diagnoses.
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PMID:An unusual case of 4-aminopyridine toxicity. 1656 54

There are many causes of prolonged postoperative muscle weakness, including drugs, residual anesthetics, cerebrovascular events, electrolyte imbalance, hypothermia, and neuromuscular disease. Neuromuscular diseases are relatively rare, with the most common being myasthenia gravis and Lambert-Eaton myasthenic syndrome (LEMS). We report an unusual case in which a patient who was given a muscle relaxant during mediastinoscopy developed postoperative muscle weakness that was ultimately diagnosed as secondary to LEMS.
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PMID:Lambert-Eaton myasthenic syndrome as a cause of persistent neuromuscular weakness after a mediastinoscopic biopsy -A case report-. 2065 98