MARK ADRIAN CRITCHLOW v UNIVERSITY HOSPITALS OF NORTH MIDLANDS NHS TRUST

In a clinical-negligence claim, breach of duty does not establish causation. The claimant must prove, on the balance of probabilities, that the breach caused or materially contributed to the alleged injury.

A Wells score indicating that venous thromboembolism is “likely” identifies a risk requiring further investigation. It does not establish that deep vein thrombosis or pulmonary embolism was present on the balance of probabilities.

In assessing causation, a normal d-dimer result is important evidence, although it is not necessarily determinative in isolation. A falling d-dimer result may be powerful evidence against an untreated acute thrombosis.

Reducing apixaban from 5 mg twice daily to 2.5 mg twice daily after six months’ treatment was not negligent where that approach accorded with the applicable NICE guidance and the manufacturer’s information.

The claimant brought a split clinical-negligence claim arising from his diagnosis and treatment at hospital in 2015. The issues at this stage were breach of duty and causation.

It was admitted that the defendant’s staff had breached their duty on 15 March 2015 by failing to calculate a Wells score and undertake appropriate imaging. The claimant alleged that he had an undiagnosed DVT or PE at that time and that earlier diagnosis and treatment would have avoided or reduced subsequent injury.

The claimant also alleged negligent treatment on 25 March 2015, when he attended a respiratory clinic, and on 8 December 2015, when his apixaban dose was reduced. The central questions were whether there had been breach on those occasions and whether the admitted breach on 15 March had caused compensable injury.

1. 25 March 2015. The contemporaneous clinical notes and letter showed, on the balance of probabilities, that the claimant’s left leg had been examined and was not swollen or tender. The evidence of both respiratory experts ultimately supported the adequacy of the assessment. There was no breach of duty by Dr Iqbal.
2. 8 December 2015. The reduction of apixaban from 5 mg twice daily to 2.5 mg twice daily was reasonable. The lower dose accorded with the applicable NICE guidance and the manufacturer’s information after six months of treatment. The evidence did not establish that a patient with more than one previous VTE episode, while off anticoagulation when those episodes occurred, required the higher treatment dose indefinitely. There was no breach of duty.
3. 15 March 2015: Wells scoring. Retrospective Wells scoring indicated that DVT and PE were “likely” in the guideline sense. That meant that further investigation was required. It did not establish the actual presence of DVT or PE on the balance of probabilities.
4. Causation. The admitted failure to investigate on 15 March did not cause injury because the claimant had not proved that he then had DVT or PE. His symptoms were capable of other explanations. His d-dimer was normal on 15 March and had fallen further by 25 March, which the court accepted was inconsistent with an untreated acute thrombosis. The later DVT diagnosed in April did not prove that thrombosis had been present in March.
5. The claim was dismissed.