From the Guidelines
Drugs cannot guarantee muscle twitching, but certain neuromuscular blocking agents (NMBAs) can be used to achieve a specific degree of neuromuscular blockade, with a goal of adjusting the degree of blockade to achieve one or two twitches. According to the clinical practice guidelines for sustained neuromuscular blockade in the adult critically ill patient 1, patients receiving NMBAs should be assessed both clinically and by TOF monitoring, with a goal of adjusting the degree of neuromuscular blockade to achieve one or two twitches. This is typically achieved through the use of NMBAs such as pancuronium, cisatracurium, or atracurium, which can be used to manage ventilation, manage increased intracranial pressure, treat muscle spasms, and decrease oxygen consumption in critically ill patients 1.
Some key points to consider when using NMBAs to achieve muscle twitching include:
- The use of NMBAs should be reserved for patients who have not responded to other treatments, and should be used in conjunction with sedative and analgesic drugs to provide adequate sedation and analgesia 1.
- The choice of NMBA will depend on the patient's underlying medical conditions, such as hepatic or renal disease, and the specific clinical goals of treatment 1.
- Patients receiving NMBAs should be closely monitored for signs of prolonged recovery or myopathy, which can be associated with the use of steroid-based NMBAs 1.
- The use of NMBAs can be associated with a range of complications, including skeletal muscle weakness, myonecrosis, and abnormal electromyography (EMG) findings 1.
Overall, while drugs cannot guarantee muscle twitching, the use of NMBAs can be an effective way to achieve a specific degree of neuromuscular blockade in critically ill patients, as long as they are used judiciously and with close monitoring. The goal of treatment should always be to achieve the best possible outcomes in terms of morbidity, mortality, and quality of life, and the use of NMBAs should be tailored to the individual patient's needs and medical conditions 1.
From the Research
Drug-Induced Muscle Twitching
- Muscle twitching can be caused by various drugs, including those that interfere with neuromuscular transmission or have a direct toxic effect on muscle fibers 2.
- Certain drugs, such as irinotecan, can induce muscle twitching as a side effect, possibly due to competitive metabolism by concomitant medications 3.
- Organic calcium antagonists, like verapamil and diltiazem, can potentiate indirectly induced muscle twitches in phrenic nerve-diaphragm muscle preparations of mice 4.
- Drug-induced myoclonus, a type of muscle twitching, can be caused by various medications, including levodopa, cyclic antidepressants, and bismuth salts, with increased serotonergic transmission potentially involved in its induction 5.
- Benzodiazepine agonists, antagonists, and inverse agonists can have varying effects on suprahyoid muscle twitching, with agonists inhibiting twitching and inverse agonists inducing twitching, both of which can be blocked by antagonists 6.
Mechanisms and Management
- The precise mechanisms of drug-induced muscle twitching are not always well established, but may involve alterations in neurotransmitter release, muscle fiber contractility, or electrolyte disturbances 2, 4.
- Management of drug-induced muscle twitching typically involves withdrawal of the offending drug, but in some cases, specific treatments may be necessary to alleviate symptoms 5.
- The effects of drugs on muscle twitching can be influenced by various factors, including concomitant medications, dosage, and individual patient characteristics 3, 6.