Treating Neuropathic Pain

Page 1

Relieving Neuropathic Pain A study to develop an understanding of the most effective use of the NMSIII in the relief of intractable chronic neuropathic pain. Initial studies have shown that the NMSIII is highly effective in providing relief from neuropathic pain that has failed to respond to other treatments. This paper outlines the background to the study, the data required to develop an in‐depth understanding of the most effective way to utilize the NMSIII and the procedures to be adopted by the clinicians assisting in the gathering of data. MF Medical Ltd 20 June 2010


INTRODUCTION This study is designed to develop a better understanding of the use of external neuromodulation for the relief of intractable localised chronic neuropathic pain and to develop treatment protocols and regimes. A small study was carried out by Guy’s & St Thomas’ Hospital in 2003 using the Neuro Trace III. It was observed that the pain relief produced was dramatic and had, at least, a medium term effect. Since this study, the device, a NeuroTrace III produced by Xavant, has been used to provide relief to a large number of sufferers. To date however there has been no detailed study to examine the most effective means of employing the technique, nor which patients are most suitable. The NeuroTrace III was designed for regional anaesthesia both nerve mapping (transcutaneous stimulation) as well as stimulation of the nerve using an insulated nerve block needle (percutaneous). Xavant have since produced a simpler device, the NMSIII designed solely for transcutaneous nerve stimulation, eliminating much of the electronic programming required in the original device but retaining the same transcutaneous stimulating capabilities. The type of stimulation should not be confused with that delivered by the standard TENS device There are many variables that potentially affect the overall performance of the technique and these have as yet not been analysed. The purpose of this study is to develop a better understanding of those variables and to validate the findings of the original study by Guy’s and St Thomas’. BACKGROUND Following the study in 2003 it became clear that short external low frequency stimulation either targeted at the site of the maximum pain or deeper afferent sensory nerves in patients with intractable pain provides significant pain relief. In that study 35 patients underwent stimulation at a frequency of 2Hz with a current of between 1mA and 15mA either directly over the affected area or to the nerve path supplying the area for a period of 5 minutes. The results were as follows No. of patients

Decrease in VAS at completion

19

100 %

4

90%

21 June 2010


4

63%

4

50%

1

25%

1

20%

1

15%

While the results are clearly of great statistical significance the study was too small to derive any data that could be of statistical significance in the detailed analysis of such variables as pain site, current amplitude improvements from different Vas starting points, skin type etc. With the development of a new device that can be made much more widely available it is clearly important to collect the data that will make such an evaluation possible. OBJECTIVES There are two main objectives of this study: 

Validation of the conclusions drawn and implied by the study at St Thomas Hospital on the effectiveness of external neuromodulation using the NMS III on providing relief from neuropathic pain To gather statistical data in order to develop protocols and treatment regimes for the alleviation of chronic intractable neuropathic pain.

There is also a secondary objective: 

Identify further evidence of the effects noted by the original study and subsequently of restoring motor function in patients.

RATIONALE FOR THESE OBJECTIVES The original study provides very clear and statistically significant evidence that external neuromodulation using the Neuro Trace 111 at low frequency can be very effective at alleviating neuropathic pain very rapidly. However, the study was small and the range of initial Vas scores (>5) was such that it is difficult to draw conclusions on the absolute effect of the technique. There are a large number of parameters involved, many of which may be interrelated. It is important to identify the effects of the individual parameters and their relationships.

21 June 2010


For example, we believe that the level of current may have a bearing on the outcomes. The selection of the level of current delivered is determined by the level of current with which the subject is reasonably comfortable. However this is itself is determined by two factors: 

The body’s own resistance to the current – a consequence of skin resistance and the nature of the tissue in the area to which the current is applied. Since the device is designed to deliver current at the rate set on the device it automatically increases the voltage to overcome the resistance, which clearly affects the total power delivered. The patient’s psychological reaction to the stimulus also has a bearing. We know that some people may tolerate a very high current – up to 20mA – and even find it to be a mildly pleasant sensation, while others find even a very small current – less than 3mA – sufficiently unpleasant to be unable to continue.

The consequence is that one patient may for example tolerate only a low current but may be experiencing a significantly higher level of total power than another who receives a significantly higher current treatment. While in each case in the original study some relief was provided we do not know the duration of the relief. Based on subsequent anecdotal evidence we know that in some, the period of relief was for several weeks (beyond the duration of the original study and the subsequent anecdotal evidence) while in other cases the period of relief was of much shorter duration and began to decline within a few days. The study has therefore been designed to shed further light on this set of variables. DESIGN The study is designed to assess both the immediate effect of the technique and the effect of a series of treatments in providing pain relief. OVERVIEW After taking a history of the subject’s experience of pain, a VAS assessment and their experience of the impact of the pain on their life quality, each participant will receive a five minute treatment of peripheral neuromodulation at 2Hz with a current of between 5 and 15mA. Following that treatment the patient will complete a further VAS assessment. Seven days later the subject will return for a further treatment. Prior to that treatment a further VAS assessment will be completed and if the patient reports a significant return of the pain over the period they will be invited to undergo twice weekly treatments for a further period of two and a half weeks. Those who have not experienced a significant

21 June 2010


recurrence of pain will be given two further treatments, one on this visit and one a further week later. A VAS score will be taken both before and after each treatment. One week after the final treatment a further VAS score and Pain Impact assessment will be carried out. On completion of the final assessment all subjects will be invited to register on the website set up to manage the test data and contribute their experiences and to provide their contact details for further follow up. Those who are not pain free but are enjoying significant relief as a result of regular treatments will be invited to re‐attend for further palliative treatments. DATA The following data will be collected for analysis ABOUT THE PERSON Age

Gender

Ethnic Origin

Level of fitness

Height

Weight

Diabetes

Other conditions

General Physical Fitness

Date of onset

Clinical diagnosis of cause – if any

Possible Cause

Site of pain

Nature of Pain

Interference with physical activity

VAS

DN4

Pain Impact

Treatments Tried

Dates

Duration

Results

ABOUT THE PAIN

21 June 2010


TREATMENT ON FIRST TREATMENT Instrument Setting

Current

Frequency

Program

Position of probe

Pain site

Path

Distance

Located on Diagram

Duration of Treatment

Vas Score After

Comments ‐ Clinician/patient

AT SUBSEQUENT TREATMENTS Time since last treatment

Date at which the pain level rose significantly

Pain Impact

Instrument Setting

Current

Frequency

Program

Position of probe

Pain site

Path

Distance

Located on Diagram

Duration of Treatment

VAS

PROCEDURES

BACKGROUND This Study is designed to explore a number of aspects of the effect of external neuromodulation. We know that with this device different patients enjoy different lengths of relief from pain. We wish to identify how long this period is and the parameters that

21 June 2010


affect and influence the period. We are also aware that patients suffering a reasonable period of relief from pain will frequently revert to normal patterns of action which in turn removes the cause of the pain. We wish to ensure that we acquire data on both these effects and therefore an assessment will be made 7 days after the first treatment. This assessment will be determine whether further treatments continue to be given weekly or are increased to twice per week.

INTRODUCTION This section covers procedures at:    

Initial treatment Prior to second treatment Subsequent treatments At conclusion of treatments

Ideally the data collection forms should be completed electronically and submitted by email, but where this is not possible manual copies of the forms are also provided. Instructions for completion of the electronic forms accompany the forms themselves which can be downloaded from www.mfmedical.co.uk. (Please note that these are not yet available.)

INITIAL TREATMENT Once a potential subject has been identified they should be screened to ensure that they match the criteria outlined above and contained on the first page of the data forms. Please complete this The patient should be asked to read the Patient Information Sheet and then sign the Patient Consent Form. The patient should then be asked to complete the VAS and Pain Impact Questionnaire in that order. You should then complete the DN4 Questionnaire with the patient. Take a history from the patient based on the Initial Treatment Form and complete the form (preferably the on line version). Carry out the treatment with the device delivering a current at as high a current as the patient can reasonably tolerate at a frequency of 2Hz for a period of 5 minutes. The patient should be comfortable with a current between 8mA and 15mA. If the patient cannot tolerate a current of above 5mA you should end the treatment.

21 June 2010


The precise mechanics of the treatment are discussed below. At the end of the treatment the patient should complete a second VAS after 5 minutes and a third after 10 minutes and the Initial Treatment Forms should be completed and submitted to MF Medical.

SECOND TREATMENT Before commencing the second treatment it is important to determine whether subsequent treatments should be twice weekly or weekly. Get the patient to complete another VAS. If the patient has seen a significant rise in pain since the completion of the first treatment it will be important to establish at what point the patient felt the degree of pain started to interfere with their normal performance. Once the decision on the frequency of treatments has been made you can proceed to treat the patient for the second time. On completion of the second treatment get the patient to complete a second VAS, complete Form 2 and submit it to MF Medical.

SUBSEQUENT TREATMENTS Subsequent treatments should be conducted in the same manner as the second treatment except that no decision has to be made about the frequency of treatment. A patient on a weekly treatment scheme should have one further treatment (total of three treatments); a patient on a twice weekly scheme should have three further treatments total of five treatments) which should provide a minimum of two and a half weeks with a substantial reduction of pain. PARTICIPANTS Subjects will be enlisted according to the following criteria: 1. 2. 3. 4.

Patient age is 18 years or older, either sex Patient has chronic neuropathic (or predominantly neuropathic) intractable pain Patient has an area of pain with a typical dermatomal distribution that can be expected to be covered with a single episode of local stimulation Patient has a Visual Analogue Scale (VAS) pain score of 5 cm (or greater) on a 10 cm line

21 June 2010


Exclusion criteria 1. 2. 3. 4. 5. 6.

Patient has a history of substance abuse or substance dependency in the past 6 months prior to baseline data collection Patient is currently participating in another clinical study Patient lacks capacity for informed consent to the trial in the view of person taking consent and/or investigators Pregnancy Patient has difficulties in adequate understanding of English for consent, clinical review and self‐completion questionnaires Patient does not permit notification to General Practitioner of enrolment in the study

21 June 2010


7. 8.

Patient has previous experience of peripheral neuromodulation. Note that prior transcutaneous electrical nerve stimulation (TENS) experience is permitted. The source of the pain is Trigeminal neuralgia or similar. Do not treat facial pain.

STATISTICAL PLAN So little is currently known about the results – other than the phenomenal immediate effects – that the intention is to carry out an initial review of the data to establish the main correlations and effects. This will be done once there is data from 50 initial treatments once the data gathered at the second treatment session is available. The initial statistics that appear important are: 1.

2.

Degree of initial pain – level of pain after treatment and related to: a. Initial degree of pain b. Site of pain c. Diagnosis of cause of pain d. Current used in treatment Duration of relief – overall and related to a. Initial degree of pain b. Site of pain c. Diagnosis of cause of pain d. Current used in treatment

At this time we will review the data and consider whether any modifications may be appropriate. Once all the data is available it will be examined to establish correlations DATA HANDLING AND SECURITY Data will be recorded on datasheets held by the clinician. Subjects will be identified by a reference number and the data relayed to us using that reference number. The clinician will maintain a register that cross references the number to the patient’s name. No data will be passed to MF Medical that can personally identify the subject. On the completion of the study patients will be invited to register at a website where they can add their comments and experiences. Registration at that website will require a “double sign up”.

21 June 2010


21 June 2010


APPENDICES A

Patient Information sheet

B

Consent Form

C

Data collection sheets

D

Patient identification register

21 June 2010


PATIENT INFORMATION Thank you for reading this and, we hope, taking part in this study. We are trying to understand why certain types of pain respond so well to the electrical stimulation provided by NMSIII used by anaesthetists. This type of device has been widely used for many years to help anaesthetists identify precisely where a nerve runs through the body. It was discovered that one side effect of using the device was the immediate relief of pain. A study was then carried out on thirty five people in a leading NHS hospital in London to see how effective it was. More than half (19) showed almost total relief of pain in the short to medium term; four reported a 90% reduction and another twelve received at least 50% reduction. The remaining three had at least some pain relief. The NMSIII has continued to be used by anaesthetists, pain clinics and physiotherapists to treat patients suffering from certain types of pain. It delivers a very low current (measured in milliamps) powered by a standard radio type battery to stimulate the nerves. We now wish to understand more clearly the most effective way of using this approach. To help us do this we need to gather much more information about your condition, the precise treatment regime and its effect. The information gathered by the Doctor or Physiotherapist who treats you will be completely confidential. Because it is confidential it will be passed to MF Medical in a way that prevents MF Medical from identifying you. At the end of your treatment your clinician may ask if MF Medical may contact you and identify your data. You are under no obligation to consent to this and we will respect your decision. In the event that you do consent to such contact MF Medical undertake not to disclose your information. You do not have to take part in this study but if you do the information gained could go a long way to helping others suffering a similar complaint.

THE TREATMENT You will receive between 3 and 5 treatments in total. Treatments will be weekly or twice weekly depending on the result of the first treatment. At each treatment either the site of the pain or the nerve supplying the site of the pain will be stimulated with a small electric current by placing a sticky electric pad near to the site and then directing the current towards the affected nerve or area of pain using a hand held probe.

21 June 2010


The device will deliver two pulses of electricity per second. Your clinician will start this at a very low level, probably less than you will be able to detect. They will gradually increase the power until you can feel a distinct twitching sensation. Some find this mildly pleasant while other people begin to find it unpleasant. Ideally you should receive the maximum power you feel acceptable. Once this power level has been identified the treatment will continue for five minutes. Should you find the sensation becoming uncomfortable during this period tell the clinician and they will reduce the power. If for some reason you decide the sensation is not acceptable tell the clinician and they will end the treatment.

THANK YOU First we hope that you gain significant pain relief from your treatments. We also hope that by collecting and analysing the data provided by this study we will be able to develop very clear protocols to help clinicians apply the best treatment for a wide variety of patients and conditions. While the results of the study may not deliver immediate benefits to you personally we hope that the close attention you are receiving ensures the best possible outcome. We also understand how unpleasant the effects of intractable pain are, not least because one of the partners in MF Medical suffers from it to a limited degree. We hope, together, we can make a difference.

21 June 2010


CONSENT FORM Patient Identification Number for this trial: CONSENT FORM FOR RESEARCH STUDY TITLE OF PROJECT: Data collection to assess the most effective way to the use of external neuromodulation for the relief of intractable localised chronic neuropathic pain Name of Researcher: I confirm that I have read and understand the information sheet dated 21 June 2010 for the above study.

Please tick to confirm

I have had the opportunity to consider the information, ask questions and have had these answered satisfactorily.

I understand that my participation is voluntary and that I am free to withdraw at any time, without giving any reason, without my medical care or legal rights being affected.

I understand that relevant sections of any of my medical notes and data collected during the study, may be looked at by responsible individuals from [company name], from regulatory authorities or from the NHS Trust, where it is relevant to my taking part in this research. I give permission for these individuals to have access to my records. I agree to my GP being informed of my participation in the study.

I agree to take part in the above research study.

__________________________ Name of Patient

______________ Date

__________________________ Signature

__________________________ Name of Person taking consent (if different from researcher)

______________ Date

__________________________ Signature

__________________________ Researcher

______________ Date

__________________________ Signature

When complete, 1 copy for patient: 1 copy for researcher site file: 1 (original) to be kept in medical

21 June 2010


notes.

21 June 2010


DATA COLLECTION SHEETS First Session   

Initial Patient Assessment Treatment Information Post Treatment

Second Session   

Pre‐treatment Review Treatment Information Post Treatment

Subsequent Sessions   

Pre‐treatment Review Treatment Information Post Treatment

21 June 2010


FIRST SESSION Pre‐Treatment Date: 1.

Patient Reference No:

Mark the areas on your body where you feel the symptoms. (Please use the appropriate symbol. Mark areas of radiation. Include all affected areas.) Numbness

N

Pressure

P

Burning

B

Pins & Needles PN Stabbing/Aching SA Other

O

Specify other

2.

Indicate the degree of pain by marking on the scale below:

No Pain

Worst Pain Possible

3.

What medication and dosage did you take during the last week?

4.

Circle the number that describes how, during the last week, pain has affected you: Does not Interfere Completely Interferes

General Activities 9 10

0

1

2

3

4

5

6

7

8

Mood 9

10

0

1

2

3

4

5

6

7

8

Walking Ability 9 10

0

1

2

3

4

5

6

7

8

21 June 2010


Work (inc Housework) 9 10

0

1

2

3

4

5

6

7

8

Relations with others 9 10

0

1

2

3

4

5

6

7

8

Sleep 9

10

0

1

2

3

4

5

6

7

8

Enjoyment of life 9 10

0

1

2

3

4

5

6

7

8

Ability to concentrate 9 10

0

1

2

3

4

5

6

7

8

Appetite 9

0

1

2

3

4

5

6

7

8

10

DN4 QUESTIONNAIRE Please answer yes or no to the following questions.

Interview of the Patient 1.

Does the pain have one or more of the following characteristics? No

Painful cold

Electric Shocks

Burning

2.

Yes

Is the pain associated with one or more of the following symptoms in the same area?

Pins and needles

Numbness

Itching

Tingling

Examination of the patient

21 June 2010


3.

4.

Is the pain located in an area where physical examination may reveal one or more of the following characteristics? Hypoesthesia to touch

Hypoesthesia to pin prick

In the painful area can the pain be increased by? Brushing

Score Yes = 1 No = 0

PATIENT INFORMATION

21 June 2010

Total = …../10


21 June 2010


21 June 2010


TREATMENT Current:

Frequency:

Position of Probe:

Position of Electrode:

Pulse Width:

Separation (cms)

Positions Electrode ‐ Probe ‐

Position of Probe:

Electrode:

(Please also show on diagram)

Treatment on: ()

Pain Site

Nerve Path

Duration of Treatment:

VAS after treatment:

Comments

21 June 2010


21 June 2010


AFTER TREATMENT – 5 MINUTES Please indicate the degree of pain by marking on the scale below:

No Pain

Patient Comments

21 June 2010

Worst Pain Possible


AFTER TREATMENT – 10 MINUTES Please indicate the degree of pain by marking on the scale below:

No Pain

Patient Comments

21 June 2010

Worst Pain Possible


SUBSEQUENT SESSIONS Pre‐Treatment Date: 1.

Patient Reference No:

Treatment No:

Mark the areas on your body where you feel the symptoms. (Please use the appropriate symbol. Mark areas of radiation. Include all affected areas.) Numbness

N

Pressure

P

Burning

B

Pins & Needles PN Stabbing/Aching SA Other

O

Specify other

2.

Indicate the degree of pain by marking on the scale below:

No Pain

Worst Pain Possible

3.

What medication and dosage did you take during the last week?

4.

Circle the number that describes how, during the last week, pain has affected you: Does not Interfere Completely Interferes

General Activities 9 10

0

1

2

3

4

5

6

7

8

Mood 9

10

0

1

2

3

4

5

6

7

8

Walking Ability 9 10

0

1

2

3

4

5

6

7

8

21 June 2010


Work (inc Housework) 9 10

0

1

2

3

4

5

6

7

8

Relations with others 9 10

0

1

2

3

4

5

6

7

8

Sleep 9

10

0

1

2

3

4

5

6

7

8

Enjoyment of life 9 10

0

1

2

3

4

5

6

7

8

Ability to concentrate 9 10

0

1

2

3

4

5

6

7

8

Appetite 9

0

1

2

3

4

5

6

7

8

Frequency:

Pulse Width:

Position of Probe:

Position of Electrode:

Separation (cms)

10

TREATMENT Current:

21 June 2010


Positions Electrode ‐ Probe ‐

Position of Probe:

Electrode:

(Please also show on diagram)

Treatment on: ()

Pain Site

Nerve Path

Duration of Treatment:

VAS after treatment:

Comments

21 June 2010


AFTER TREATMENT – AFTER 5 MINUTES Please indicate the degree of pain by marking on the scale below:

No Pain

Patient Comments

21 June 2010

Worst Pain Possible


AFTER TREATMENT – 10 MINUTES Please indicate the degree of pain by marking on the scale below:

No Pain

Patient Comments

21 June 2010

Worst Pain Possible


IDENTITY REGISTER

Name

Reference No

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

21 June 2010


21 June 2010


IDENTITY REGISTER – CONTINUED (16 – 30)

Name

Reference No

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

21 June 2010


21 June 2010


IDENTITY REGISTER – CONTINUED (31‐45)

Name

Reference No

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

21 June 2010


21 June 2010


Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.