Chapter 36 Management of Restless Legs Syndrome in the Hospital and During Surgery
Restless legs syndrome (RLS) is a quiescegenic disorder; its symptoms emerge at rest. Therefore, a critical worsening of RLS during hospital stays, which include bedrest, is common.
Pathophysiologic Aspects of Perioperative Restless Legs Syndrome
The emergence of symptoms at rest is one of the essential symptoms of RLS,1 and immobilization is used to provoke RLS symptoms and derived periodic limb movements (PLM) in the suggested immobilization test.2 From this context, it becomes clear that bedrest during hospital stays and, even more so, immobilization of the legs (possibly also other parts of the body) can trigger RLS symptoms in mild cases or contribute to a critical worsening in more severely affected patients. Intraoperative and postoperative blood loss reduces body iron stores and represents an additional contributing factor (see Chapter 9 for the role of iron metabolism and anemia in RLS).
Both RLS and PLM have been observed during epidural and spinal anesthesia, with symptoms occurring either during anesthesia or as the effect is wearing off. Shin³ pointed out that severe restlessness may occur during epidural anesthesia in patients with RLS. He describes a 30-year old woman with RLS since childhood, which worsened during pregnancy, who had a cesarean section with epidural anesthesia. The patient experienced an urge to move the legs but was unable to do so due to the motor block and violently thrashed her head and arms. Symptoms improved with diazepam.3 Ward4 describes his own experience of an RLS-like syndrome during epidural anesthesia. While the motor block was active and the effect of anesthetic was wearing off, he suffered from a severe urge to move the legs; symptoms were later alleviated by walking around. Although Ward used the term “akathisia” in this case report, the similarity with RLS is evident. Because a previous surgery in spinal anesthesia with carbocaine and epinephrine was uneventful, the author, who is a psychiatrist, attributed his symptoms to the effect of droperidol, which was administered together with metoclopramide in the preoperative phase.4
Periodic limb movements during wakefulness (PLMW) were observed in a patient without any history of RLS or PLM during epidural and spinal anesthesia, during the phase of motor paralysis.5 The same authors had reported PLM during wakefulness in another patient during spinal anesthesia, in whom PLM during sleep had also been documented. It was not stated whether this patient also had RLS.6 Watanabe and colleagues5 used the term “anesthesia-related PLM” (AR-PLM) to characterize these phenomena. They suggested that AR-PLM and PLM during sleep may share a common etiology with spinal anesthesia or sleep-related suppression of descending inhibitory spinal pathways or corticospinal tract dysfunction.5
Several other case reports deal with myoclonus-like and other involuntary movements in patients undergoing surgery during spinal or epidural anesthesia, or in the immediate postoperative phase.7–12 In some of them, it is controversial whether the movements resembled PLM or spinal or propriospinal myoclonus. A prospective study found that transient RLS occurred in 8.7% of 202 patients undergoing spinal anesthesia for orthopedic and other surgery.13
An imbalance in sensorimotor integration13 may underlie the occurrence of RLS and PLM during spinal anesthesia, specifically during its wearing off. Another suggested mechanism is reduced blood flow in the lower extremities or spinal cord.14 The use of epinephrine in spinal anesthesia prolongs duration of effect15 but may reduce blood flow to spinal cord.16
New onset of RLS independent of type of anesthesia has also been reported in patients undergoing surgery for other reasons. For example, familial RLS first manifested itself after heart surgery in a 9-year-old boy17—in this case, the interaction compromised brain iron regulation and blood loss was discussed. A recent survey focused on patients undergoing lung transplant and reported an extremely high frequency of 47.2%. The authors discuss that the increased incidence of steroid-induced diabetes, drug-induced anemia, renal dysfunction, and neuropathy might all contribute to an increased risk for RLS in this specific surgical population.18
Treatment
General Principles
1. Monitoring Iron Status
Continuous monitoring of iron status is critical in all patients with RLS undergoing surgery or hospital stays for other reasons. Replenishing body iron stores improves baseline conditions for RLS treatment. In patients with severe RLS and anemia, blood transfusions may be indicated to treat the RLS. Dramatic improvement after blood transfusions of severe iron-deficient RLS apparently refractory to treatment have been reported.19 Parenteral iron substitution is indicated for rapid correction of iron deficiency. Iron status should be checked in RLS patients even before minor surgery and iron replacement initiated if body iron stores are found to be low (refer to Chapter 34).
2. Ensure Continuous Drug Delivery
In the immediate perioperative phase, oral medications often have to be discontinued. Because continuous and efficient RLS treatment is critical in this phase, nonoral drug delivery has to be established when oral medication is withheld for a prolonged period of time. Baseline RLS treatment should be continued as long as possible before surgery. One should remember that re-emergence of RLS symptoms after temporarily stopping oral medication greatly varies due to variable plasma half-life of the medication, from 2 to 4 hours with levodopa20 to 65 hours with cabergoline.21
Systemic Dopaminergic Treatment
Recent studies have shown that transdermal delivery of dopaminergic drugs like rotigotine patch22 or lisuride patch23 is efficacious in RLS. Patch applications may provide a useful treatment mode for patients in the fasting state. Although stable plasma levels can be reached, and patch treatment is expected to provide a good baseline treatment, it remains to be established if the onset of action is fast enough to realize shorthand adaptations to increasing dose needs in inpatients. Rotigotine has already been approved for Parkinson’s disease.
Related posts:
Clinical Science of Restless Legs Syndrome
Introduction: Comorbid Disorders and Special Populations
Restless Legs Syndrome as a Movement Disorder
Restless Legs Syndrome in Neurological Disorders
Spinal Cord, Dopamine, Opiates, and Restless Legs Syndrome
Restless Legs Syndrome Morbidity: Sleep and Quality of Life
