FALL 2009

Restless Legs Syndrome

Myra Aultman CRNA
University of Alabama at Birmingham, Callahan Eye Foundation Hospital

Restless legs syndrome (RLS) has been reported to occur in as much as 15% of the geriatric population. []] It is characterized by unpleasant sensations in the legs that are relieved by limb movement. [2] This movement can make it difficult to proceed with an ophthalmic procedure when the patient is receiving monitored anesthesia care (MAC) or local anesthesia. Attempts to reduce the involuntary movements by giving additional sedation have often augmented the movement, resulting in either a conversion to a general anesthetic or discontinuation of the procedure. Augmentation has been defined as “a worsening of RLS symptom severity characterized by the occurrence of RLS symptoms earlier in the day, by a shorter latency to symptoms at rest, increased intensity of symptoms, and a spreading of RLS symptoms to previously unaffected areas of the body.” [3]

Can certain drugs used daily by anesthesia providers cause the symptoms of RLS to worsen? Little information is available addressing this question. However, spontaneous movement during propofol administration has been reported in children. [4] The movements have been described as “myoclonic” and “myotonic” in both children and adults. [5]

Krauss et al reported two case reports of propofol induced dyskinesias in patients with Parkinson’s disease who underwent stereotactic pallidotomy while off levodopa medication. [5] In both cases, the patients began to display dyskinesias after propofol administration. However, in both cases, the symptoms subsided within minutes after the sedation was discontinued. The authors of those case reports suggested that since propofol can cause abnormal movements, it might not be an ideal drug during neurosurgical procedures under MAC in patients with movement disorders.

What can be used in these patients that will not exacerbate leg movement? Alpert et al [1] suggested physostigmine as a possible treatment in a case report of a 77 year old man having a MRI of the cervical spine. In that report, leg movement continued even though a satisfactory level of sedation was maintained with a propofol infusion. Additional boluses of propofol and hydromorphone had no effect on the leg movement and the procedure was interrupted. A dose of glycopyrrolate 0.2 mg and physostigmine 1 mg IV was given and all leg movement ceased after 90 seconds, allowing the procedure to continue. The authors of that case report suggested that the physostigmine reversed the effects of the sedative causing the leg movement. [1]

Oral ketamine has also been suggested to hold promise as a treatment for RLS [5] A case report by Kapur and Friedman described how a 70 year old woman was treated successfully with an oral dose of 30 mg of ketamine mixed in 50 ml of water. The patient felt relaxed and noted no adverse effects from the ketamine but did have improvement of her RLS symptoms. [6]

One additional treatment for this disorder described as a case report involved the use of compression stockings. [7] The stockings were used during local anesthesia for a cataract extraction in a patient with such severe RLS symptoms that she requested a general anesthetic due to a fear of being unable to lie still during the procedure. Ironically, this patient was obese, and the anesthesia provider decided to use graded elastic compression stockings as prophylaxis against deep vein thrombosis. The patient was able to lie still and not move at all during a sub-Tenon’s block or during the surgical procedure.

Traditionally, dopamine agonists have been prescribed as a management in this disorder. Therefore, anesthesia providers might recommend that the patient with RLS continue these drugs on the day of surgery. They might also recommend that the patient with RLS avoid caffeine, alcohol, and nicotine in addition to having iron and electrolyte deficiencies corrected. [8] Finally, benzodiazepines and opioids can be helpful in the management of these patients.

References

[1]        Alpert CC, Tobin P, Dierdorf SF. Physostigmine for the acute treatment of restless legs syndrome. Anesth Analg 2005; 101:726-727.
[2]        Rama AN, Kushida CA. Restless legs syndrome and periodic limb movement disorder. Med Clin N Am 2004; 88: 653-667.
[3]        Hogl B, Garcia-Borreguero D, Kohnen R, et al. Progressive development of augmentation during long-term treatment with levodopa in restless legs syndrome: results of a prospective multi-center study. J Neurol. Springer-Verlag 2009. Sept. 11. 2009.
[4]        Borgeat A, Popovic V, Meirer D, Schwander D. Comparison of propofol and thiopental/halothane for short-duration ENT surgical procedures in children. Anesth Analg 1990; 71:511-515.
[5]        Krauss JK, Akeyson EW, Giam P, Jankovic J. Propofol induced dyskinesias in Parkinson’s disease. Anesth Analg 1996; 83:420-422.
[6]        Kapur N, Friedman R. Oral Ketamine: A promising treatment for restless legs syndrome. Anesth Analg 2002; 94:1558-1559.
[7]        Krishna M. Novel use of graded elastic compression stockings. Anaesthesia 2007; 62:973.
[8]        Medcalf P, Bhatia KP. Restless legs syndrome. BMJ 2006; 333: 457-456.