Medical Acupuncture Online Journal, Volume 13 #2, case 3

Percutaneous Electrical Nerve
Stimulation In The Treatment Of Irritable
Bowel Syndrome: A Case Report
Gerald W. Grass, MD

Abstract
Background A growing number of research findings indicate that dysregulation of the autonomic nervous system may play a major role in the development and perpetuation of irritable bowel syndrome (IBS) symptoms. Recently, several reports have demonstrated that percutaneous electrical nerve stimulation (PENS) of spinal or peripheral nerves alleviated symptoms in other conditions believed to arise from autonomic nervous system dysfunction.
Objective To illustrate the use of Craig-PENS in the treatment of IBS symptoms.
Design, Setting, and Patient A case report of a patient with a 16-year history of diarrhea-type IBS symptoms.
Intervention The patient was treated with Craig-PENS in a standard arc pattern with points at T9, T12, L3, L5, and S3.
Main Outcome Measure State of IBS symptoms following treatment.
Results Following 15 treatment sessions, the patient reported dramatic and long-lasting diminution of symptoms.
Conclusion The case reported herein suggests that Craig-PENS is a promising therapeutic modality for the treatment of IBS symptoms in those individuals with diarrhea-type patterns.

KEY WORDS
Craig-PENS, Irritable Bowel Syndrome, Percutaneous Electrical Nerve Stimulation, Autonomic Dysfunction, Neuromodulation

INTRODUCTION
Irritable bowel syndrome (IBS) represents a constellation of symptoms including abdominal cramping, bloating, constipation, and/or diarrhea as well as multiple extra-intestinal symptoms. This syndrome affects approximately 10%-15% of the US population.1 The economic impact of this disease is estimated at $41 billion in direct health care
expenditures in the 8 most industrialized countries worldwide.2

Although the exact etiology of IBS remains unclear, a number of research reports have demonstrated disordered central and autonomic nervous system function in subgroups of patients with IBS. These studies point to a generally decreased parasympathetic outflow or increased sympathetic activity in conditions usually associated with decreased gastrointestinal motility, while other studies have found either increased cholinergic activity or decreased sympathetic activity in patients with symptoms compatible with increased motor activity.3 In addition, autonomic dysfunction may represent the physiological pathway accounting for many of the extra-intestinal symptoms seen in patients with IBS, such as chronic fatigue, bladder dysfunction, and myofascial pain.4

While various treatment modalities have been used in an attempt to ameliorate the symptoms of IBS, including traditional pharmaceuticals, hypnotherapy,5,6 Chinese herbs,7 cognitive therapy,8 and biofeedback,9 few studies have focused on direct stimulation of the autonomic nervous system in an attempt to overcome colonic dysfunction.10-12

Recently, several studies have focused on a form of neuromodulation known as percutaneous electrical nerve stimulation (PENS). PENS has been shown to be an effective treatment in several conditions, including low back pain and sciatica,13,14 headaches,15 bone pain from metastatic cancer,16 and diabetic neuropathy.17 In addition, recent reports
have demonstrated that percutaneous electrical stimulation of spinal or peripheral nerves can alleviate symptoms in other conditions believed to arise from autonomic nervous system dysfunction, such as urinary incontinence due to detrusor overactivity.18-20

My hypothesis was that a similar beneficial effect might be achieved in patients with IBS. Current evidence suggests an autonomic nervous system dysfunction in the pathogenesis of IBS symptoms. Thus, Craig-PENS was chosen as treatment for this case.

CASE REPORT
A 48-year-old woman was referred from her primary care physician for assistance with IBS symptoms. She developed symptoms in 1983, including increasing episodes of explosive diarrhea, abdominal pain and bloating, cramps, and recurring episodes of cystitis.

Over the preceding 16-year period, numerous specialists at a local community and university hospital had evaluated her complaints with a battery of diagnostic tests. In addition to routine laboratory studies including complete blood cell count, SMA 12 (blood chemistry panel), fecal analysis, food and environmental allergy testing, and thyroid studies, she had undergone upper and lower gastrointestinal series, gastric motility studies, colonoscopy, cystoscopy, intravenous pyelography, pelvic sonography, computed tomography, and laparoscopy. No pathology was ever noted and she was subsequently diagnosed as having IBS.

The patient reported that her symptoms frequently interfered with daily activities and she could not travel far from home due to recurrent bouts of diarrhea. In 1990, her symptoms became so intense that she underwent a trial of “bowel rest” for 3 months; a Groshung catheter was inserted for hyperalimentation. This treatment provided little symptomatic relief and she continued to have frequent episodes of diarrhea.

At presentation, the patient indicated that she had an average of 3-4 days per week when she experienced 10-12 episodes of diarrhea per day as documented in her daily journal, with more frequent episodes occurring under emotional stress.

Her medical history was significant for a tonsillectomy in 1953, cholecystectomy in 1983, and right mastectomy for breast cancer in 1990. She reported no history of any other medical or psychiatric problems. Her medications included dicyclomine, 20 mg 4 times per day, and acetaminophen-propoxyphene, 1 tablet every 4 hours as needed. She had been given trials of antidepressants, narcotic analgesics, and other antispasmodics over the years without appreciable benefit. In addition, she had used numerous over-the-counter and nutritional supplements as well as various restrictive dietary regimens in an attempt to alleviate her symptoms, all without significant relief.

Physical examination was remarkable only for well-healed incisions from the previous surgical procedures and multiple tender myofascial bands noted in the paravertebral areas bilateral to the T9 to S3 spinous processes.

After an explanation of the risks and potential benefits, the patient consented to a trial of Craig-PENS therapy for the IBS symptoms. She was asked to continue to daily record her physical symptoms and number of bowel movements.

TREATMENT
The treatment modality used in this case was Craig-PENS. This technique was originated by William F. Craig, MD13-17,21 who developed this modality in the late 1970s as an “acupuncture-like” method of PENS for the treatment of pain. It involves the placement of thin stainless steel acupuncture needles through the skin into muscles and nerves related to the dermatomes, myotomes, or sclerotomes based on the segmental pattern of nerve distribution thought to be involved in the underlying pathology. A microcurrent electrical stimulator is then attached to the needles in a prescribed pattern, known as a montage, and then set to stimulate the chosen points for a specified frequency, intensity, and duration. These variables are recorded and adjusted at each treatment session, depending on the patient’s clinical response to the previous session. In this case, prior to the beginning of each treatment session, the patient’s daily journal was reviewed and her progress assessed to determine the appropriate treatment frequency.

The patient was placed in a prone position on the treatment table and 10 32-gauge, 60-mm Seirin “L” type (Seirin-Kasei Co, Shimizu City, Japan) acupuncture needles were inserted bilaterally at 1.5 cm lateral to the inferior tip of the T9, T12, L3, L5, and S3 spinous processes to a depth of approximately 2-3 cm. Insertion points T9, T12, L3, and L5 were chosen due to the presence of tender myofascial bands at those levels, as well as their known contribution to various autonomic ganglia involved in gastrointestinal regulation. The insertion point S3 was added in an attempt to help alleviate the patient’s symptoms of recurring cystitis.22

No attempt was made to elicit the traditional De Qi sensation during needle insertion; the needles were not manipulated or twirled following insertion. A microcurrent generator (AWQ-104 Series; OMS Medical Supplies, Braintree, Mass) with an asymmetric biphasic waveform pattern, a pulse width of 400 milliseconds, and a continuous duty cycle was used to stimulate the electrodes. Prior to each treatment session, the microcurrent generator was calibrated using a digital multimeter (Kaito MY66; Kaito Electronics, Walnut, Calif) and then connected to the percutaneous electrodes in a standard arc pattern according to the Craig-PENS protocol (Figure 1). The probes were stimulated for 30 minutes at each treatment session with an initial frequency of 4 Hz and current settings of 20 mA.

The patient received 15 consecutive treatments, 1 each week for 15 weeks over a 4-month period. The current settings remained constant on all treatment sessions. Frequency settings were increased to 8 Hz on the 3rd session and
maintained at that frequency for all subsequent sessions.

RESULTS
The patient reported beneficial effects following the 2nd treatment session: the number of diarrhea episodes had diminished to 3-5 per day, with bouts occurring 3 times per week, and the abdominal pain of the past 2-3 years had that she had had for the past 2-3 years had receded. At that point, the input frequency was increased to 8 Hz, according to the Craig-PENS protocol, to investigate any additional improvement.

After the 5th treatment session, the patient reported that the frequency of diarrhea episodes had been reduced to 3-4 episodes per day, 1-2 times per week and she reported feeling physically and psychologically healthier.

A minor setback in the patient’s progress was noted following the 9th session. During the week following that session, she indicated experiencing extreme stress; she reported 15 diarrhea bowel movements after a particularly stressful day. However, by the time of her 10th session, her bowel action had been reduced to 1-2 episodes per day, 1-2 days per week.

The patient’s progress quickly resumed and by the 15th session, she described only 1 diarrhea episode in the previous 3 weeks and had discontinued all of her medications. She then began a maintenance schedule of 1 treatment session every 3 months; she has been followed for an additional 18 months as of this writing. The patient continues to maintain her improvement and has reported only 2 recurrences of the diarrhea. In addition, she also stated that the frequent episodes of cystitis have not troubled her in the last 18 months. The overall results of her treatment sessions are summarized in Figure 2.

There were no adverse effects attributable to the Craig-PENS therapy noted at any time during or after the treatment sessions. Craig-PENS patients may experience “rebound” periods during which the painful symptoms become worse for several days. Since this treatment was not for a primarily painful condition, a rebound was not expected and none was reported by the patient.

DISCUSSION
While the exact etiology of IBS remains elusive, recently published research findings indicate that dysregulation of the autonomic nervous system may play a major role in the development and perpetuation of symptoms.23-26 These reports point to generally increased cholinergic activity or decreased sympathetic activity in patients with symptoms compatible with increased colonic motor activity (as seen in this case). However, no attempt was made to differentiate between parasympathetic hyperactivity and sympathetic hypoactivity in this patient.

The Craig-PENS technique generally uses a progression of electrical frequencies adjusted to the patient’s response. The regimen usually involves a frequency sequence of low (2-4 Hz), intermediate (15-30 Hz), high (100 Hz), and then back to low (4-6 Hz). The rationale for this progression is based on preliminary studies conducted by Dr Craig, who found this progression effective. Recently, however, Dr Craig and his group have called these findings into question and are attempting to determine which frequency or combination of frequencies is optimal for specific conditions.21 (Considering this fact, when the patient requested that the stimulus frequency be held at 8 Hz, given her dramatic response to the treatment, it was believed at that point that improvement on her current level of progress could not be effected and therefore, deferral to her request was made. Whether some additional benefit may have been achieved by following the standard protocol is unknown and may be a fruitful area for further investigation.)

Although the exact mechanism of action of Craig-PENS is unknown, the improvement caused by this form of neuronal stimulation may be due to a “resetting” of 1 or several of the parallel neuronal feedback systems involved in the regulation of gut motility. Although a review of the autonomic and enteric innervation of the gastrointestinal system is
beyond the scope of this report, this effect may occur centrally and/or peripherally because recent evidence suggests that the peripheral endings of sensory neurons are involved in vasodilatation, increases in vascular permeability, contraction and relaxation of smooth muscle, and depolarization of autonomic efferent neurons in the prevertebral ganglia.3 It is therefore possible that electrical stimulation of spinal nerves may not only stimulate cord, medullary, and higher brain centers to effect change, but also may spread in an antidromic fashion to modify local reflex arcs regulating gastrointestinal tract homeostasis.

CONCLUSION
Craig-PENS appears to be a promising therapeutic modality for the treatment of IBS symptoms in those individuals with diarrhea-type patterns. The technique is minimally invasive, requires only 30 minutes per week, and in this case, was not associated with adverse effects or safety issues. It is hoped that this report will encourage other clinicians who are treating patients with IBS to try this procedure and report their findings to help determine the overall applicability of this treatment in IBS.

REFERENCES

AUTHOR INFORMATION
Dr Gerald W. Grass is Board-certified in Emergency Medicine, and is a Diplomat of the American Board of Medical Acupuncture and the American Academy of Pain Management. He is a Fellow of the Association of Emergency Physicians, and is currently in private practice specializing in Medical Acupuncture and Pain Management.

Gerald W. Grass, MD, DABMA
8874 Lovers Lane Rd
Corfu, NY 14036
Phone: 716-599-3594 • E-mail: gwgrass@hotmail.com