A case of neuropathic pain and electroconvulsive therapy
A 32-year old male had a 10-year history of chronic right arm and shoulder pain. His pain started spontaneously as an aching, burning pain in the right shoulder, which then spread down the arm to the hand, and proximally to the lateral portion of the right side of the neck. He also complained of pain radiating into the scapular area and toward the thoracic spinal column. He described the pain as burning, sharp and crushing in nature.
Which one of the following condition is the possible diagnosis of this presentation?
- Neuropathic Pain
- Spinal Stenosis
Neuropathic pain is defined as pain that results from damage or abnormal function of the central or peripheral nervous system. Neuropathic pain can be difficult to manage using conventional treatment modalities. The usual treatments include opioids, anticonvulsants, antidepressants, antiarrhythmics and interventional procedures (e.g., spinal cord stimulators, nerve blocks, and neurosurgical ablation). Unfortunately, many patients fail these treatment modalities. Though not well studied, a few case reports illustrate the benefit of electroconvulsive therapy (ECT) in the management of chronic pain syndromes.
The exact origin of ECT is unknown. It probably dates back to the medical usage of eels by the Romans to treat headache and later the experiments of Italian naturalists with electricity1. Further, the physician Galen employed electricity in the treatment of gout and other illnesses. Later, a Hungarian psychiatrist, Laszlo Meduna, was credited with the first modern use of convulsive therapy. He was intrigued by the studies of Nyiro and Jablonski2 in the 1920s, which demonstrated that patients with schizophrenia seemed to have a lower incidence of epilepsy than the general population. They postulated that dementia praecox (the old term for schizophrenia) had a curative effect on epilepsy, and Meduna wondered if the reverse might be true. He found that convulsions induced with intravenous Metrazol or intramuscular camphor could treat psychosis. Though Meduna is credited as the father of convulsive therapy, it was not until the late 1930s that Drs. Bini and Cerletti in Italy were successful in using electric currents to induce therapeutic seizures3.
His past medical history included hypertension, seizure disorder and depression. He was treated as an inpatient and outpatient multiple times for depression.
Examination and Laboratory Investigations
Physical examination: His right arm was noted to have decreased sensation to light touch and cold along the posterior aspect of the arm. There was hyperesthesia to pinprick in the right posterior shoulder area, right posterior arm, and the distal lateral wrist, encompassing an area of approximately 5 cm by 7 cm. There was obvious atrophy of the pectoralis muscle. He was able to demonstrate at least 3/5-muscle strength in the shoulder.
Imaging studies: MRI of his brachial plexus showed no anatomical abnormality, and MRI of the cervical spine showed no cord or nerve compression. An EMG showed chronic changes consistent with brachial plexopathy with involvement of the infraspinatus and supraspinatus muscles.
Treatment included continuous infusions of local anesthetics via an interpleural catheter, an intravenous lidocaine test, stellate ganglion blocks, TENS and interscalene brachial plexus blocks, all of which resulted in temporary mild pain relief, but no long-lasting relief. Medications included methadone 100 mg a day in divided doses, hydromorphone 2 mg orally every 8 hours as needed, gabapentin 1200 mg 3 times a day, clonidine 0.1 mg daily, clonazepam 1 mg four times a day and ibuprofen 800 mg 3 times a day.
Polypharmacy, interventional procedures, and behavioral pain management were unsatisfactory. He developed recurrent severe depression and attempted suicide. He was admitted to a psychiatric hospital for depression and suicidal ideation. While hospitalized, he underwent five right unilateral electroconvulsive treatments under methohexital (80 mg) and succinylcholine (100 mg) anesthesia, with average seizure duration of 62 seconds. He experienced relief of both the chronic pain and depression.
The patient spent approximately 2 weeks in the psychiatric hospital and then was discharged home. Subsequently, he did relatively well and began to taper his medications, including the opioids. During the recovery phase, he rated his pain as 3/10 on a visual analog scale. He was happy with the response and increased his activity level significantly. Unfortunately, eight weeks later, the pain recurred. Although it is tempting to attribute the entire pain syndrome to a psychiatric disorder, this patient had bona fide evidence of brachial plexopathy and appeared to be in pain. The ECT treatments correlated with the 8-week period of pain relief.
It is widely observed and acknowledged that there is an association between chronic pain and depression. Consequently, many physicians initially believed that antidepressants and psychotropic drugs might relieve chronic pain by improving depression. Although ECT may be considered a non-pharmacologic method of treating depression, there are undoubtedly significant pharmacologic effects of ECT on the brain. ECT is often the only known effective treatment for severe depression resistant to medications. ECT may also be an effective and relatively safe treatment for psychosis and mania. Not surprisingly, ECT is rarely considered for chronic intractable pain syndromes today, although there is an old, but rather sparse literature on the therapeutic use of ECT for pain.
Mandel4 reported that ECT alleviated symptoms for four of six patients suffering from chronic pain and depression. Bloomstein et al5 reported that out of twenty-one patients who received ECT for concurrent affective symptoms, twenty experienced improvement in their pain levels, and concluded that ECT could be an effective treatment modality for patients who have chronic pain complicated by affective symptoms. Further, King et al6 described a patient with depression who developed RSD and was helped by ECT. The patient had total resolution of pain for several hours after the first treatment. On the other hand, McCance et al7 reported that ECT was not effective in the treatment of post-stroke thalamic pain. The authors performed a pilot study in 3 patients who received six bilateral ECT treatments over a period of two weeks and observed no improvement in thalamic pain or mood. Furthermore, Salmon et al8 could not verify a positive response to unilateral ECT treatment for thalamic pain.
Even though ECT was used for various types of intractable chronic pain during the 1940s and 1950s, it is not now often used for pain, for obvious reasons. Nonetheless, concerns about such factors as amnesia and injury from ECT make the option rather unpopular, despite the fact that more recent evidence, again from case reports, suggests that ECT may benefit subsets of patients with chronic pain.
Although ECT is widely accepted as a treatment for severe depression, it is seldom used in the treatment of chronic pain, despite the fact that chronic pain and depression frequently occur together. The case report rekindles a discussion about the possible use of ECT in depressed patients presenting with intractable pain syndromes. Although prospective randomized studies are needed, such studies most likely will never be done. Nonetheless, there is anecdotal evidence that ECT may alleviate symptoms of depression and pain in some patients who have failed conventional treatment.
- Harms E. The origin and early history of electrotherapy and electroshock. Am J Psychiatry 1956; 111:933-934.
- Nyiro J, Jablonsky A. Einige daten zur prognose der Epilepsie, mit besonderer rucksicht auf die konstitution. Psychiatr Neurol Wochenschr 1929; 31:547-549.
- Cerletti U, Bini L. Unnuevo metodo di shockterapie “L’elettroshock.” Bollettino Accademia Medica Roma 1938; 64:136-138.
- Mandel MR. Electroconvulsive therapy for chronic pain associated with depression. Am J Psychiatry 1975; 132:632-636.
- Bloomstein JR, Rummans TA, Maruta T et al. The use of electroconvulsive therapy in pain patients. Psychosomatics 1996; 37:374-379.
- King JH, Nuss S. Reflex sympathetic dystrophy treated by electroconvulsive therapy: Intractable pain, depression, and bilateral electrode ECT. Pain 1993; 55:393-396.
- McCance S, Hawton K, Brighouse D et al. Does electroconvulsive therapy (ECT) have any role in the management of intractable thalamic pain? Pain 1996; 68:129-131.
- Salmon JB, Hanna MH, Williams M et al. Thalamic pain-the effect of electroconvulsive therapy (ECT). Pain 1988; 33:67-71.