Sarah Woodwark, Healthcare Partner, discusses case law on consent in medical negligence cases.
Causation in consent cases has been an area fraught with difficulty particularly since the House of Lords’ decision in Chester v Afshar . The difficulty was enhanced by the fact that the Lords were not unanimous in their decision to modify the conventional approach to causation in such cases and lawyers have wrestled with the decision ever since.
Chester v Afshar – The facts
The Claimant suffered from longstanding back problems and underwent a series of treatments to alleviate her pain. MRI scanning revealed that several intervertebral discs had protruded into the spinal canal. She was anxious to avoid surgery if at all possible. She consulted Mr Afshar, a Consultant Neurosurgeon, who advised surgery. He was clearly under a duty to the claimant to advise her of the risks associated with the operation, including a one-two per cent risk of cauda equina syndrome (CES).
The evidence about what was warned of pre operatively was contested and on the issue of warning of the risk of CES the trial judge found against Mr Afshar. He had performed the operation skilfully, but unfortunately the complication of CES occurred with significant consequences for the claimant. The trial judge also found that if the Claimant had been appropriately warned then she would have wished to explore other options.
It was not found that she would not have had the surgery at all , or the surgery would have been performed by someone else. She would have had the same surgery, only at a later date. The risk of CES would have been exactly the same and there was no means by which the risk could have been reduced or eliminated.
Given that the risk was small, and it seemed random as to whether it occurred at all, the majority held that if surgery had been performed on a different day, on the balance of probabilities, it would have been successful and CES would not have occurred. The odds of CES occurring or being avoided were not affected by anything Mr Afshar did, or did not do, He did not, in the conventional legal sense, cause the damage. Nonetheless the court felt it necessary to amend the standard test for causation to permit the Claimant to recover her damages in full.
One assumes that the court was in receipt of expert evidence in relation to the random nature of the injury. However, it is not immediately apparent why the court concluded that the risk was unavoidable on the day of surgery but would, on balance, have been avoided on another day, aside from applying a simple balance of probabilities approach. One wonders whether it might simply be the case that medical science is not able to isolate the causative factor behind the injury.
The policy supporting the patient’s right to know of risks in order to make informed decisions affecting their own bodies was, clearly an important factor behind the decision. The patient’s right to know had been infringed by Mr Afshar, and the majority in the Lords clearly felt the need to override conventional causation principles in this scenario in order to give effect to the patient’s right.
The practical problem which ensued was, and remains, an evidential one. Following any surgical intervention where a complication ensued, the risk of which was small, it was a low hurdle for patients to clear to simply say: ‘I wasn’t warned and if I had been I would have deferred the surgery to another time’ and to recover damages in full.
Montgomery v Lanarkshire Health Board 
The issue of consent in the context of the doctors’ duty was more recently under the spotlight in the case of Montgomery v Lanarkshire Health Board . The facts of the case were striking in that the doctor seemingly considered it acceptable not to discuss with diabetic expectant mothers the risk – agreed to be around nine-ten per cent - of shoulder dystocia associated with a vaginal delivery. The complications associated with shoulder dystocia however, carried a much smaller risk, around 0.2 per cent of brachial plexus injury, and 0.1 per cent of cord compression causing cerebral palsy.
Diabetic mothers are known to have an increased risk of having a large baby and consequent shoulder dystocia. In this case it was known during the pregnancy that the claimant’s baby was large. The doctor concerned sought to justify her decision not to discuss the risks of shoulder dystocia with the claimant on the basis that she, in common with most women in this situation, would then have sought to have a caesarean section.
The situation was aggravated when, at 36 weeks gestation, the doctor decided that the claimant should not have a further ultrasound scan at 38 weeks because she was becoming concerned about the baby’s size and her ability to deliver vaginally. The claimants labour was induced and the birth which followed was, on any analysis, horrific. The claimant’s son was eventually delivered vaginally but sustained cerebral palsy and Erb’s palsy in the process. Had he been born by caesarean section he would have been uninjured. It was however decided at first instance that if an appropriate discussion had taken place the claimant would not have had a caesarean section.
The obligations of a treating doctor in discussing material risks associated with medical procedures when dealing with consent was considered at length by the Supreme Court. What qualifies as a material risk consists of both objective and subjective elements and depends on the degree and odds of risk, and what a reasonable person in the patient’s position would regard as material, or that which the doctor reasonably ought to be aware that that the patient would attach significance to.
The factual question of what Mrs Montgomery would have done had she been warned of the risk of shoulder dystocia was re-visited on appeal. The Supreme Court reversed the trial judge’s decision, concluding that the claimant would have opted for a caesarean section if she had been appropriately warned.
The case therefore had significant implications for treating doctors in relation to the extent of the discussion which ought to take place with the patient and be documented in their records. The traditional Bolam test on breach of duty was abandoned in consent cases. Taken alongside the Chester v Afshar decision on causation, the claimant’s prospects for full recovery of damages in consent cases increased. An injured patient, one might suggest, is highly likely in retrospect to say that had they been warned of the risk that transpired, which was of specific relevance to them, then they would have opted for a second opinion or to defer treatment to another day. Unsurprisingly, the uncertainty around the degree to which subjective factors can and should be explored by doctors was the cause of some unease.
Duce v Worcestershire Acute Hospitals NHS Trust 
The issue of causation in consent cases came before the court again in May this year. In this case, the claim failed at first instance and the Claimant appealed. She had suffered from heavy and prolonged periods and also back pain; despite several discussions with her doctors in which she was advised on less invasive treatments, she insisted on having a total abdominal hysterectomy. In clinic her treating gynaecologist noted that the risks associated with the procedure had been explained. The specific risk of chronic or neuropathic pain was not discussed with the claimant. She underwent surgery, which was performed competently, but subsequently developed chronic pain.
The claimant’s case evolved in relation to the extent of the warning it was alleged ought to have been given regarding post-operative pain. Although warned of post-operative pain in general, the claimant was not warned of the possibility of neuropathic pain and her consultant accepted that she would not have so warned. The claimant’s case was clearly weak on this issue particularly since guidance from the Royal College of Obstetricians and Gynaecologists did not refer to neuropathic or chronic pain.
On appeal it was argued that the appropriate tests in Montgomery on breach and in Chester on causation had not been appropriately applied by the Trial Judge. In relation to breach the Appeal Court agreed with the Trial Judge’s finding that there was no duty to warn of chronic or neuropathic pain as there was an insufficient understanding of it among gynaecologists at the time. That was not the end of the matter however, and the court went on to consider causation and the application of Chester in such cases. The policy behind the decision and the Courts’ desire to protect patient’s rights were again discussed.
In Duce, the claimant’s pleaded case was that if she had been properly warned then she would not have proceeded with the operation on that day. On appeal, it was argued that she did not have to prove this, and only had to prove that the injury was intimately involved with the duty to warn; that the duty was owed by the doctor performing the surgery to which the patient had consented; and that the injury was the product of the very risk the claimant should have been warned about when consenting.
But this argument was rejected and it is clear that to succeed the claimant must prove that, on the facts, if s/he had been appropriately warned then the operation would not have been performed on that particular day. The approach to causation in Chester was described as ‘exceptional’ and it was emphasised that to rely on it, it must be pleaded and proved in evidence that the claimant would have deferred surgery.
The decisions in Duce and Chester are interesting on the contrasting facts. In Chester the claimant was keen to avoid surgery, in Duce the claimant was adamant that she wanted to have surgery.
Both these cases and the decision in Montgomery demonstrate the court’s recognition of the policy behind the need to protect patients’ right to know of the risks associated with any procedure they subject their bodies to, the tension that places on the test for causation in negligence.
Lord Hoffmann, dissenting in Chester expressed his discomfort at the modification of the usual causation test in this way. The injury sustained was an affront to the claimant and the claimant’s right to make an informed choice which, he suggested, might attract a small award of damages, but not full recovery of damages as this was not what was caused in the true sense by the negligent failure to warn. The incidence of CES was not caused by the doctor’s negligence nor could it be said that the risk of injury was in any way affected by the doctor’s actions.
What this means for Claimants / The implications
It is clear that any claimant seeking to rely on Chester in future must plead their case and be ready to prove that the operation would in fact have been deferred. Claimants will need to deploy very good factual evidence to succeed in such a case in future.
The wider issue of the appropriate scope of the tort of negligence and how far that should and can go to protect patient’s rights to make decisions, is an issue worthy of further attention
Perhaps an award of a specific sum to compensate patients for the infringement of their right to make an informed decision should be given further consideration, not least because it will provide a degree of certainty for lawyers advising those on both sides. The option to make a small payment promptly in recognition of the infringement of a patient’s right may even go some way to bolstering and repairing the doctor-patient relationship.