In the AN case, the Supreme Court of Appeal held that despite the failure by the hospital to properly monitor the mother and foetus, during delivery, that did not cause the brain damage to the baby, which resulted from an unpreventable cause.

The hospital had a legal duty to monitor the condition of the mother and foetus and act appropriately on the results of monitoring. The hospital failed to do so and therefore their conduct was wrongful and negligent.

The baby sustained a brain injury during labour. The cause of the brain damage was an acute profound hypoxic ischaemic (APHI) injury. Each of the terms is described below:

  • Acute – sudden and not developing over time;
  • Profound – complete or total;
  • Ischaemic – restriction of the blood supply; and
  • Hypoxic – reduction of the oxygen supply.

In other words the cause of the brain damage was a sudden, total, persistent reduction of blood supply to the brain which led to a lack of oxygen supply. APHI injuries are usually caused by perinatal sentinel events. The type of sentinel event which occurred was an umbilical cord compression. In the circumstances, the only way to reduce the likelihood of damage to the baby was to expedite the delivery by way of a vacuum extraction which would have taken at least 20 minutes.

The SCA had to consider whether there would have been any warning signs of an APHI injury and if there weren’t any warning signs, whether it would have been possible to prevent the damage to the brain when the cord compression occurred by expediting the delivery.

If there were warning signs then the medical staff may have pre-empted the sudden fall of the foetal heart rate. According to the expert evidence monitoring of the foetal heart did not necessarily mean that there would have been prior warnings of a sentinel event. The court, therefore, found that the claimant did not prove that there were any warnings of an impending sentinel event.

One expert testified, without challenge, that the cord compression would have occurred 30 minutes prior to delivery. This was insufficient time to deliver the baby so as to avoid the brain damage.

In order to establish factual causation, it had to be proved that if the cord compression had been detected within a reasonable time, intervention within a reasonable time would probably have prevented the brain damage. The claimant did not establish factual causation.

This judgment highlights that wrongfulness (the breach of a legal duty) and fault (negligence) should not be conflated with factual causation.