Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1762617 (weakness)
 37,932 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We evaluated the method used intraoperatively to assess the degree of neuromuscular blockade prior to pharmacologic reversal to determine its role in preventing residual blockade in the postanesthesia care unit (PACU). We studied 38 patients who received a nondepolarizing muscle relaxant during general anesthesia for carotid endarterectomy or thoracotomy. The anesthesiologist assessed the degree of neuromuscular blockade intraoperatively prior to pharmacologic reversal either by the standard method of visually counting the number of evoked thumb twitches elicited by supramaximal train-of-four stimulation of the ulnar nerve (i.e., thumb train-of-four count), or by an alternative method such as 1) visually counting the number of evoked orbicularis oculi muscle twitches elicited by supramaximal train-of-four stimulation of the facial nerve, or 2) observing the patient for clinical evidence of partial recovery (e.g., swallowing or attempts to breathe). Residual blockade in the PACU was defined as 1) a train-of-four ratio less than 0.70 (measured by a mechanomyograph), or 2) the inability of the patient to perform clinical tests of neuromuscular function (e.g., a sustained head lift for 5 seconds) and evidence of neuromuscular weakness that was resolved following administration of edrophonium. Five of the 22 patients (23%) in whom one of the alternative methods was used had residual blockade in the PACU; none of the 16 patients with a thumb train-of-four count of 3 or 4 before pharmacologic reversal of NMB had residual blockade in the PACU (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Method of intraoperative monitoring of neuromuscular function and residual blockade in the recovery room. 135 37

Neuromuscular blocking drugs are valuable adjuncts to the practice of pediatrics. Monitoring of drug effects is technically more difficult in the younger patient. Nevertheless, careful observation of drug effects will improve the usefulness of NMB and safeguard the patient from prolonged weakness. Although there are differences in neuromuscular function with age in the pediatric age range, the differences between the NMB currently available are greater than the differences between the patients. Thus, the only uniform finding across age and all drugs is that onset of drug effect is more rapid in the infant than in the child when circulatory function is normal. In general, children require more of all NMB on a mg/kg basis than do infants or adults to obtain the same effect. Children recover from NMB more rapidly than do patients of other ages. Infants, however, may recover more rapidly than do any other patients from the effects of drugs such as mivacurium which are metabolized in the plasma. Tables 4 and 5 summarize doses, onset of action, and duration of NMB. Please note in Table 4 that succinylcholine is only used for endotracheal intubation, whereas the other nondepolarizing muscle relaxants can be used for endotracheal intubation or to maintain some degree of muscle paralysis in the child whose trachea is already intubated. Nondepolarizing muscle relaxants (e.g., mivacurium, ORG 9426, atracurium, vecuronium) are used both for initial bolus for endotracheal intubation and maintenance of muscle relaxation. Long-acting drugs (e.g., pancuronium, pipecuronium, and doxacurium), however, are used more commonly in small incremental doses to maintain muscle paralysis in patients already intubated. The advantages of these long-acting drugs are minimal cardiovascular side effects (i.e., tachycardia or hypotension from histamine release) and longer dosing interval. In all children, the dosing interval should be adjusted to the needs of the individual. In children with renal insufficiency or in those receiving drugs which impair neuromuscular function (e.g., aminoglycosides), the interval at which supplemental doses are required is longer than normal.
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PMID:Neuromuscular blocking drugs in infants and children. 829 8

Pharmacologic administration of sedatives is used routinely in the care of the critically ill to enhance patient comfort and optimize care. Long-term administration of NMB drugs is far less frequent but often occurs in patients with greater organ dysfunction. The experience of several authors using NMB drugs in the ICU is summarized in Table 5. Both classes of drugs have potential untoward effects. Some are readily predictable; others are not. NMB drugs enjoy a long record of safe, effective use during the perioperative period, but certain issues linger in defining appropriate administration to critically ill patients. Major concerns focus on the appropriate drug selection and delivery, monitoring, and neuromuscular recovery of patients who receive NMB drugs for longer than 24 hours. The development of myopathy and paresis has been increasingly recognized after prolonged use of NMB drugs in the ICU. Further investigation needs to fully characterize this process, identify those at risk, and outline a mechanism to prevent or limit the injury. Prolonged weakness may occur secondary to changes in the basic pharmacology and elimination of NMB drugs in ICU patients. Pathophysiologic changes in the nerve, muscle, or neuromuscular junction may also play a role in the development of some cases of prolonged weakness or myopathy after discontinuation of NMB drugs. Concerns about the potential for direct or indirect toxicity of NMB drugs to skeletal muscle and in the CNS remain. Resolution of these issues will improve the selection and optimal administration of sedative and NMB drugs in the ICU setting.
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PMID:Complications associated with sedative and neuromuscular blocking drugs in critically ill patients. 853 89

Muscle weakness, particularly impairment of the respiratory muscles, is a frequent abnormality in ICU patients. This is more relevant in some clinical situations--for example, in weaning patients from mechanical ventilation. Intensive care procedures that are designed to "rest" respiratory muscles, such as mechanical ventilation, may also contribute to impaired muscle function. Pharmacologic administration of glucocorticoids, several antibiotics, NMB agents, and so on has the potential to cause untoward effects. The development of myopathy and prolonged paresis has been increasingly recognized after prolonged use of these drugs in the ICU. Pathophysiologic changes in the nerve, muscle, or neuromuscular junction associated with the patient's underlying condition may also play a role in the development of impaired function. The assessment of muscle function is difficult and inaccurate. The techniques developed have a poor predictive value because of the difficulty in making the measurements in uncooperative patients and the lack of standardization. Furthermore, it is likely that some voluntary maneuvers underestimate muscle strength. Invasive procedures such as phrenic nerve stimulation or EMG recording are also of limited value.
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PMID:Muscle dysfunction in the intensive care unit. 1038 66