How valuable is expert evidence when assessing a patient in a vegetative state?

The legal system is sometimes called upon to assess the level of mental functioning of individuals in a persistent vegetative state (PVS). Such questions can arise both in cases involving the possible withdrawl of life-sustaining treatment, and in compensation claims. In addressing these questions the courts rely on expert evidence, but experience shows that medical experts may disagree as much as laymen about the level of an individual's mental functioning.

A foundation stone of the legal debate around PVS is the decision in Airedale NHS Trust Respondents v Bland [1993] AC 789. Anthony Bland was a victim in the Hillsborough disaster and suffered anoxic brain damage following severe injuries which resulted in his brain being starved of oxygen. The case was the first decision by the Court of Appeal that life-sustaining treatment could be removed. The case involved several expert witnesses. An appeal to the House of Lords failed as the 'court had been assisted by expert medical evidence from witnesses of the highest calibre and of the very greatest experience'. These experts included Professor Jennett, a globally recognised expert on PVS. He considered that there would be no benefit in maintaining life-sustaining treatment because he could see no prospect of recovery of cognitive function.

In Bland PVS was characterised as follows: 'Its distinguishing characteristics are that the brain stem remains alive and functioning while the cortex of the brain loses its function and activity. Thus the PVS patient continues to breathe unaided and his digestion continues to function. But although his eyes are open, he cannot see. He cannot hear. Although capable of reflex movement, particularly in response to painful stimuli, the patient is incapable of voluntary movement and can feel no pain. He cannot taste or smell. He cannot speak or communicate in any way. He has no cognitive function and can thus feel no emotion, whether pleasure or distress.'

Twenty years on from Bland, questions concerning the degree of mental function-ing of patients with PVS continue to come before the courts; the legal framework, however, has changed in several ways.

Determining best interests

In Re M [2011] EWHC 2443 (Fam), the issue that the court had to determine was whether it was in the 'best interests' of M for life-sustaining treatment to be withdrawn. The Mental Capacity Act 2005 established a new framework for making decisions when an individual is deemed to not have capacity. The factors that fall to be considered are set out in section 4 MCA and the person's participation in any acts or decisions is encouraged. Applying the test is of course very difficult when the patient is in PVS and expert witness evidence will be required. Mr Justice Baker found that it was not in the best interests of the patient in a minimally conscious state for artificial nutrition and hydration to be withdrawn. The court had to identify the factors that were relevant to the patient's best interests and carry out a balancing exercise.

Baker J highlighted how medical science had developed from the 1990s when the concept of persistent or permanent vegetative state (originally 'PVS' but now more commonly 'VS') was first considered by the English courts. A new concept is that of the minimally conscious state (MCS), a state just above that of vegetative state, but which also involves very significant limitations on consciousness and with a quality of life that many would find impossible to accept were they able to consistently express themselves with full competence.

The court heard from leading experts in neuro-rehabilitation including Mr Derar Badwan and Professor Lynne Turner-Stokes. The experts put forward contrasting views on M's level of consciousness and, most importantly, whether it was in the best interests of M for ADH to be withdrawn.

Barker J did not accept the evidence of Professor Turner-Stokes that M's overall experiences were wholly negative. He accepted that her life had a number of negative aspects, but also found that it had positive elements. Baker J accepted the evidence of Mr Badwan that there was a reasonable prospect that M's positive experiences and quality of life could be extended by changes to her care plan.

Bland and Re M highlight the importance of the expert witness. However, the judge also attached some weight to the carers' oral evidence. Their evidence suggested that M did have positive experiences, and that, although her life was extremely restricted, it was not without pleasures, albeit small ones.

Question of compensation

Mental functioning may also fall to be assessed in compensation claims. The objective of damages is to put the claimant, so far as money can, back in the position he would have been but for the accident and give him the same quality of life that he might have enjoyed. In addition, general damages are awarded for 'pain, suffering and loss of amenity'; this involves an assessment of the level of apprehension and awareness that an individual may have. Often, different experts will be instructed for claimant and defendant and it is not uncommon for there to be a divergence of opinion over a claimant's level of functioning. This in turn can have an impact on valuing future care, accommodation and therapy needs.

Brown v Emery [2010] EWHC 388 (QB) concerned an interim payment application made by the claimant for £800,000 to facilitate the purchase of accommodation. The applicant (B) suffered a serious head injury following a road traffic accident. Liability had been admitted by E. B was a protected party and had a deputy. She had been diagnosed as being in a PVS and remained hospitalised in a rehabilitation unit.

In the interim payment application heard by Teale J, it was common ground that when the issue of damages is tried, the trial judge will make an order for the payment of a capital sum in respect of certain heads of loss and an order for periodic payments in respect of other heads of loss. One of the issues in this case was whether accommodation costs should be taken into account for the purposes of valuing the likely capital sum that would be awarded at a trial in accordance with the principles of Eeles (Cobham Hire Services Ltd v Eeles [2009] EWCA Civ 204).

Evidence was submitted from the claimant's experts, Professor Barnes, a professor in rehabilitation medicine, and Steven Docker, an accommodation expert. The defendant did not rely on any expert evidence.

Professor Barnes, consultant neurologist, expressed the opinion that 'there is about a three-year timescale for improvement' of injuries of the type suffered by B. Professor Barnes also stated, when dealing with B's 'long-term prospects/accommodation', that 'she is a young girl and'¦ it would be entirely inappropriate for any consideration to be given to admission to a long-term nursing unit. Her parents are extremely keen for her to return to a family home, albeit that their present accommodation is unsuitable'¦ It would be entirely possible for B to be nursed at home with an appropriate 24-hour care package and access to relevant therapy.' On this basis it was submitted that it was inappropriate for B's long-term care to be in a nursing unit and appropriate for her to be cared for at home, as long she was in suitable accommodation.

The defendant submitted that the medical evidence did not show that B would benefit from being cared for in one place rather than in another place. He also submitted that there was no evidence that she could recognise her parents. Teale J held that the accommodation costs should not be awarded at the interim stage because there was a real issue between the parties as to whether it would be in the claimant's best interests to reside in such accommodation or whether she should remain in publicly funded accommodation.

Similar issues arose in Mabiriizi v HSBC Insurance (UK) Ltd [2011] EWHC 1280 (QB). This case also concerned an application for an interim payment to purchase accommodation. Sharp J refused the application as there remained a dispute as to whether the claimant should live at home or in residential accommodation. While it was submitted on the claimant's behalf that there was some evidence of progress, the defendant counsel submitted that the claimant was wholly unaware of his surroundings.

In these cases, the issue of whether the claimant would remain in publicly funded accommodation or move home with a full care package will have had significant implications for the claimant's compensation. Therefore, the parties would need to obtain detailed witness evidence and expert evidence on the issue; it could not be dealt with at the interim stage.

There are few experts in the UK who are sufficiently qualified in the areas of neuroscience and rehabilitation to be able offer an informed view on brain function when a patient is in PVS. Yet, at the same time, advances in medicine mean that more patients will survive devastating and debilitating head injuries. So, how does the law decide whether a life is worth living or how a life should be lived when an individual cannot express their desires? Experience suggests that expert evidence can only take the debate so far and that an element of subjectivity will always intrude.