An individual coming out of a Coma doesn’t just wake up, but will go through a gradual process of regaining consciousness. This stage of recovery is called Post Traumatic Amnesia ( PTA) and may last for hours, days or weeks.

When fully conscious, the brain, is constantly active - perceiving, processing and remembering information. Following emergence from coma individuals may go through a period of Post Traumatic Amnesia (PTA), which is a higher level of consciousness and awareness than coma, but less than full-consciousness. A mild concussion may also cause a brief period of Post Traumatic Amnesia.

Post-Traumatic Amnesia is considered a stage in the brain’s recovery process [1][2]. During this period individuals may be:

• disoriented - confused about where they are, who those are around them are and the time, date or year.
• Highly distractractable
• Have difficulty with thinking, memory and concentration [3].
• They may be afraid, dis-inhibited, agitated and emotionally labile [3].

Individuals in Post Traumatic Amnesia are partially or fully awake, but are confused about the day and time, where they are, what is happening and sometimes who they are. They will not be able to store continuous or recent memory, such as what happened just a few hours or even minutes ago. If physically able, they may wander, so it is important to make sure their surroundings are free of any hazards.

Behavioural changes can occur during this phase, where the patient may be quiet and passive, or aggressive, abusive and agitated [3]. Some individuals during this stage may give inappropriate comments and actions. Patients usually have little or no awareness of these cognitive and behavioural impairments and will usually remember nothing of what happened during Post Traumatic Amnesia, even though they appear fully awake.

The assessment and rehabilitation process does not commence until PTA is finished. The patient’s memory is unable to retain information which makes most rehabilitation techniques ineffective and the ability to gain valid information from assessment impossible.

WHAT THE FAMILY CAN DO DURING THE POST-TRAUMATIC AMNESIA PERIOD

There are a number of things family and friends should remember during this stage. Firstly, any challenging behaviour is likely due to the effects of the injury and therefore should not be taken personally. In most cases a person will usually not remember most, if any, of what has happened during this time. Second, too much stimulation during this time can increase the person’s level of confusion and distress. During PTA, patients may not be able to cope with too much noise or activity, so it’s important to keep activity around the individual to a minimum [4]. The same rule applies when trying to communicate with the person; avoid overloading the person with too much information at once and keep sentences short [4]. It is important to carefully watch for cues of discomfort with levels of touch, noise, or activity around the person, so appropriate adjustments can be made.

Thirdly, families should be encouraged to get enough sleep and ‘time-out’ from the hospital for self-recuperation. You may feel that you should be by your loved one’s side 24 hours a day, but it is important to provide a sufficient level of self-care. The emotional and physical tole of watching and being next to your loved one continuously can be exhausting. Allowing time to rest will mean your ability to provide care for the injured person is more effective during crucial periods, such as rehabilitation. If sleep proves too difficult, trying different relaxation techniques or having some time to chat with someone you trust and feel comfortable with may be invaluable assistance to long-term well-being.

Upon discharge, it is important to gauge how the person’s safety could be compromised as a result of their amnesia. Special precautions such as preventing the person from driving and not leaving them alone in the house may need to be taken.

WHEN DOES POST-TRAUMATIC AMNESIA FINISH?

PTA is usually seen as ending when the patient begins to retain information—such as where they are, why they are in hospital, and the month and year; in other words continuous memory returns. However, individuals during PTA may show brief periods of orientation and ability to recall information; these are known as ‘memory islands’[3]. Therefore, assessment should take place at regular intervals to get a clearer picture of the degree of PTA. The good news is that signs of orientation and ‘memory islands’ are indicators that the person may be emerging from PTA.

Following PTA, more assessments are conducted to gain further insight into the nature and extent of injury, along with the commencement of rehabilitation. Behavioural issues sometimes worsen at this point as the patient becomes aware of what has happened to them, and may have difficulty coping with the various emotions that arise.

PTA AS GUIDE FOR RECOVERY

Along with Glasgow Coma Score, length of PTA is commonly held to be one of the best measures of severity of brain injury. This also means it can give a rough indication as to the degree of recovery that can be expected. Within Australia the 'Westmead Post Traumatic Amnesia Scale' is the most widely used measure of Post Traumatic Amnesia [5]. The scale was designed to provide an objective and standardised measure of the period of Post Traumatic Amnesia. The measure is generally delivered by a member of the medical team and consists of 7 questions related to orientation in time and place and 5 memory questions, allowing for a maximum score of 12 [6]. A person is reported to be out of PTA once they can achieve a perfect score for 3 consecutive days, with the first of the three days considered the date of emergence from PTA [6]. The reason for not accepting that the PTA stage is complete on the first perfect score, involves the occurrence of ‘islands of memory’ and the ability of some patients to display brief periods of orientation in time and place [6]. Because a patient recalls some information one moment does not mean that may recall it soon after.

For further information on how the scale is used, access the Westmead PTA Scale website: http://www.psy.mq.edu.au/pta/page6.html

General indication of injury severity as a function of PTA duration:
• PTA less than 5 minutes = “very mild injury”
• PTA between 5-60 minutes = “mild injury”
• PTA between 1-24 hours = “moderate injury”
• PTA between 1-7 days = “severe injury”
• PTA greater than 7 days = “very severe injury”

References

[1] Marosszeky, N.E.V., Ryan, L., Shores, E.A., Batchelor, J. & Marosszeky, J.E. (1997). The PTA Protocol: Guidelines for using the Westmead Post-Traumatic Amnesia (PTA) Scale. Sydney: Wild & Wooley. Website: http://www.psy.mq.edu.au/pta/page6.html

[2]Headway UK. (2008). Post-Traumatic Amnesia-Fact Sheet. Retrieved March 29, 2008, from http://www.headway.org.uk/sitePages.asp?step=4&contentID=1334&navID=115

[3] Wilson, B. A., Herbert, C. M., & Agnes, S. (2003). Behavioural Approaches in Neuropsychological Rehabilitation: Optimising Rehabilitation Procedures. New York, NY: Psychology Press.

[4]Brain Injury Rehabilitation Unit (Sydney). (2006). Post-Traumatic Amnesia. Retrieved March 29, 2008, from http://www.swsahs.nsw.gov.au/biru/BIU%20Homepage/info/pta.asp

[4] NSW Institute of Trauma and Injury Management. (2008). Post Traumatic Amnesia (PTA). Retrieved March 29, 2008, from http://www.itim.nsw.gov.au/go/knowledge-base/clinical-resources/head-and-facial-injuries/
other-information-on-head-injuries/post-traumatic-amnesia-pta

[5] Marosszeky, N.E.V., Ryan, L., Shores, E.A., Batchelor, J. & Marosszeky, J.E. (1997). The PTAProtocol: Guidelines for using the Westmead Post-Traumatic Amnesia (PTA) Scale. Sydney: Wild & Wooley. Website: http://www.psy.mq.edu.au/pta/page6.html