Special patients and other issues
Please note - These procedures have been devised to improve the test's standardisation for the following patients:
Chronic amnesic patients
Patients who are chronically amnesic are those who can not meet the criteria of the Westmead PTA Scale for a period of 12 months after emerging from coma. They are patients who are eligible to use the Westmead PTA Scale, however their injury is so severe that they can not cope with the demands of the scale. In our experience it is advisable to persevere with PTA testing for as long as possible. We believe it is not unreasonable to ask that the PTA examiner continue to test a patient for 3 months on the scale when they find that the patient's score has reached a plateau. At this time the Clinical Neuropsychologist needs to analyse the patients poor performance and rule out any other alternate explanations. It is also advisable to give the patient a break from testing for a period of 2 - 4 weeks. If possible repeated attempts should be made to reach the Westmead PTA Scale's criteria for a year after emergence from coma. If no change has occurred then the patient's memory functioning needs to be reviewed annually for the rest of their life.
Nonverbal patients present a particular challenge to the users of the Westmead PTA Scale. The examiner requires some skill and patience.
To test nonverbal patients reliably they need to be able to do one of the following:
- Consistently and accurately indicate yes / no to all questions (i.e. by head shaking or hand gestures).
- Produce legible writing, or be able to use a keyboard, an alphabet board or other augmentative communication device (consult with the Speech Pathologist).
- Have sufficient upper limb control to point / indicate the correct answer from 3 options presented on either a white board, a large piece of paper or a series of cardboard cards (like flash cards). The size of the print on the white board / paper / cards used will be determined by the degree of accuracy of movement over which the patient has control.
These communicate modes can be used to break the non-verbal patients into 3 groups:
Group 1 - Administering the Westmead PTA Scale to a patient who can only indicate yes or no
It should be noted that PTA testing by this method is a relatively slow process; the length of the patient's concentration span will also determine if this is a worthwhile exercise (be aware that the patient may fatigue).
Basically, the examiner is required to present 3 options for all questions, and the patient needs to indicate yes or no appropriately to each of the options as presented.
Examiner: How old are you? Are you 19 years old?
Examiner: How old are you? Are you 20 years old?
Examiner: How old are you? Are you 21 years old?
Examiner: What day of the week is it? Is it Thursday?
Examiner: What day of the week is it? Is it Thursday?
Examiner: What day of the week is it? Is it Thursday?
Questions 1, 3, 4, 5, 6 and 9 follow this step by step response process, using the choice of 3 options rules as outlined in the PTA Questions section (i.e. the options must be in sequential order and the correct answer's position must vary for each question). Question 8 is already in a yes / no format, whereas Questions 2 and 7 need to be broken up into their component parts.
Question 2 is asked in 3 parts. If the patient's D.O.B. is 19/11/64. The examiner first asks the patient 'Were you born on the 18th, the 19th or the 20th of the month ?'. For the patient to be correct they would need to indicate, after each part: 'no', 'yes', 'no'. The examiner then asks 'Is your birthday in September, October or November ?', to which they should respond: 'no', 'no', 'yes'. The last question to the patient is 'Were you born in 1964, 1965 or 1966 ?', where the patient would then need to respond: 'yes', 'no', 'no'. The patient needs to get all 3 parts of their D.O.B. correct to score 1 point.
Question 7 needs to be broken up into its 2 parts. 'What is the name of this place ? Is it your home, a hotel or a hospital ?' If hospital is answered then you must ask, 'What is the name of this hospital - Nepean Hospital, or Westmead Hospital, or Liverpool Hospital ?' The patient must get both parts correct to score 1 point.
The picture cards should be presented as in presentation mode 1 (see the PTA Questions section). The patient is shown all 9 cards one at a time and asked to indicate the 3 target cards by saying 'yes' or 'no' to each card, e.g. 'Is this one of the pictures I asked you to remember yes or no?' Score 1 point for each card that is correct.
Group 2 - Administering the Westmead PTA Scale to patients who can use writing or a communication device to indicate choice
Administer the scale as if in speech mode, however, you will get the answers via paper or a communication device. (A pen and some paper is required, or a communication device may be used. Contact the Speech Pathologist for further advice.) If the patient's writing is too hard to read or the communication device is too time consuming, use the pointing to items option that is presented on the following page.
Group 3 - Administering the Westmead PTA Scale to patients who can use arm movement to indicate choice
For these patients, the 3 options that the patient is to pick from are written down on a white board, large piece of paper or flash cards (cardboard cut-out answers). The patient is then asked to point to the correct answer. The examiner can have the questions ready or write them as they go. (If you are using flash cards, these should be prepared before each session.) The picture cards should be presented as in presentation mode 2 (see the PTA Questions section). All 9 cards are spread out in front of the patient and they are asked to point to or pick up the 3 pictures they had to remember from yesterday. (A white board, large sheet of paper or flash cards, as well as a texta marker and a small table are required for this procedure.)
Please note: In this communication mode, the examiner should avoid eye contact and be aware of any body language so as not to give any cues to the patient.
If used, these nonverbal procedures should be briefly described in the patient's medical record as well as noted on the MR-120 Form (make a brief note under the total score line). Any changes in procedures should also be noted, for example, when procedures change from nonverbal to verbal administration.
The examiner may find that a patient always answers 'Monday' to Question 5 (or they may answer 'Monday' to every question). In this situation, the examiner should ask the patient to think hard and repeat the question using the choice of 3 options procedure (see PTA Questions section). NB: The 3 options should not include the perseveration response. This restatement of the question might help change the patient's mind-set, although they still may not get the question right. This issue highlights the fact that not only does the PTA score represent the actual response of the patient, but it also represents the best response of the patient for that particular test occasion (i.e. every opportunity was given to the patient to answer correctly).
To some extent use of this procedure is up to the discretion of the examiner (the same applies when a patient makes a slip of the tongue). However, this discretion should be used sparingly as some may argue that the only reason a patient answered an item correctly was because they were given 'two bites of the cherry'. If the patient continually requires this procedure to get an item right, it should be discussed with the Clinical Neuropsychologist and reported in the notes.
Non-english speaking patients
For patients who can not speak English, testing should be conducted via an interpreter. (If one is available a professional interpreter is recommended.) The interpreter should be instructed to relay the questions and answers in a simple and objective manner which offers no extra help to the patient. The PTA examiner, who is alongside the interpreter, records whether the patient answered the questions correctly or incorrectly. Then as usual the interpreter goes through what has to be remembered for tomorrow. (NB: When reporting these scores in the medical record one must acknowledge the use of an interpreter.)
Dealing with agitated patients who are aggressive and prone to wander is difficult as they can not settle even for a short PTA test. In these cases, every effort should be made to assess the patient as the agitation may be a symptom of the post-traumatic amnesia. Suggested strategies include: (1) using other staff members to help settle the patient while testing takes place; (2) testing in an environment which has no distractions; (3) stressing to the patient that testing must be done every day and will only take a few minutes; (4) correcting the patient's answers only after all questions have been given; (5) and using praise and positive rewards for good behaviour.
Patients in borderline PTA
Borderline patients provide another interesting challenge for examiners. These patients consistently score 10, 11, 12 for a week or two without meeting the scale's criteria. Clinically other team members are saying that the patient has improved. (This may or may not be the case.) In this situation, one should consult with the Clinical Neuropsychologist.
Please note: Scoring for these special procedures is exactly the same as scoring for the standard procedures. However, please remember to use an asterisk when the choice of 3 options is given.
The nexus with GCS
There is no clearly defined time when Glasgow Coma Scale (GCS) testing should stop and PTA testing should start. However, on theoretical grounds, looking at the GCS scoring chart one could assume that testing could take place when a patient's GCS Motor Score equals 6 (i.e. the patient is able to follow commands). But there also needs to be a degree of consistency associated with these scores, perhaps a period of 24 hours would suffice.
Retrograde amnesia is the other amnesia noted in the head injury literature. It is the condition where the patient can not remember events for a period before the accident. The Westmead PTA Scale does not attempt to measure this type of amnesia.
As a screening device for mild to moderate head injury (PTA < 24 hours) the Westmead PTA Scale is at a distinct disadvantage because it requires patients to stay in hospital for a minimum of 4 consecutive days while testing is carried out. What is needed is an adaptation of the Westmead PTA Scale which is suitable for screening purposes. To test this new instrument Gronwall & Wrightson's 1980 study provides a useful guide.
The use of orientation boards is common in rehabilitation facilities even though there are few well controlled studies into their efficacy (Richardson, 1990). If orientation boards are used on your ward, they should never refer to the PTA picture cards and should be removed or covered up prior to testing.
Role of parents/relatives and carers
Parents/relatives and carers should be made aware of the importance of PTA testing at the outset. Their support and encouragement is required to allow the patient to perform at their best. However, this encouragement should never be allowed to spill over to become actual coaching. Parents / relatives and carers should never 'rehearse' the scale with the patient during the day. This could have one or more of these consequences: artificially inflating the patient's score; confusing the patient; placing undue pressure on the patient and discouraging their co-operation.
The photos (4" x 6") of the regular examiner plus the 2 other staff members should be fairly close shots of the head and face with the same lighting and background. (This can best be achieved by taking the photos during the same session.) The photos can either be in black and white or colour - so long as they are uniform. The 2 other staff members chosen should be of the same sex and roughly similar in features to the examiner. They must also have little contact with the inpatients who are to be tested.
The Westmead PTA Scale video
The Westmead PTA Scale Video was produced by Peter Heldorf (Audio Visual Services, Westmead Hospital) in 1989. This 14 minute video is a useful introduction for novices to the administration of the Westmead PTA Scale, as well as being a simple revision exercise for those familiar with the scale.
PTA data bank
Units are encouraged to set up a PTA Data Bank. All that is required is to copy all MR-120 Forms before they are placed in the patient's medical record. These copied forms should then be placed in a central location. This will allow units to conduct annual quality audits of the forms to check scoring.
PTA testing takes 2 - 3 minutes for most patients. However, for some patients, like those that have an extremely severe head injury, or those who require nonverbal testing procedures, it may take up to 15 minutes. This is because of the extra work the examiner has to do.
Frequently asked questions
Can we use our own picture cards? Won't any 9 pictures do?
No. The Westmead PTA Scale was developed using a set of 9 cards in an attempt to measure post-traumatic amnesia in a standard fashion. This allows one to compare patients from different hospitals. Therefore, it is advisable to use the standard cards and procedures.
Where can we get the picture cards and how much do they cost?
Picture cards and instructions are available from the Department of Rehabilitation Medicine, Westmead Hospital, Westmead NSW 2145. They can be purchased by sending a cheque for $50.
Why does the patient have to score 12 out of 12 for 3 consecutive days, with the picture cards changing, before they can be deemed to be out of PTA?
This criterion was established to avoid the common occurrence of 'an island of memory' in post-traumatic amnesia. Thus, the period of 3 days was settled upon in order to make sure that the patient's performance on the Westmead PTA Scale is consistent.