Stroke after carotid surgery

Miss C, a 30-year-old accountant, developed an asymptomatic left-sided neck lump. A CT scan revealed a 23 x 17 x 27mm mass at the carotid bifurcation consistent with a carotid body tumour. Miss C saw a vascular surgeon, Professor A, who noted there was no significant medical or family history and confirmed that she was normotensive with no neurological signs. 

He explained that this was a rare tumour with the potential for malignancy and recommended surgical excision, which he undertook the following day. Miss C signed a consent form completed by Professor A for “radical excision of left carotid body tumour”.

During surgery, the carotid bifurcation was damaged, resulting in rapid blood loss of approximately 1,100mls. Professor A recorded that the bleeding was controlled by clamping the common carotid artery three times for a total of 16 minutes. The injury was repaired “with difficulty” using a 5/0 prolene suture and at the end of the procedure there was good flow in the internal carotid artery. 

Postoperatively, Miss C was transferred to the ICU where she was extubated and initially appeared drowsy, but had no obvious neurological deficit. She remained stable overnight but the following morning appeared drowsier and was noted by the nursing staff to have profound right-sided weakness. 

Dr B, ICU anaesthetist, reviewed Miss C and attributed her drowsiness to opiate toxicity and prescribed naloxone. Miss C’s condition did not improve and when Professor A saw her, he arranged an urgent MRI scan. This demonstrated a large left middle cerebral artery territory infarction with complete occlusion of the entire extra-cranial left common carotid, internal carotid, external carotid arteries. Despite further intervention by the ICU team and neurosurgeons, Miss C suffered permanent brain damage with severe hemiplegia and cognitive impairment requiring continuous nursing care. 

The family of Miss C initiated proceedings against Professor A and Dr B, as they were critical of numerous aspects of their care.

Expert opinion

Expert opinion agreed that arterial bleeding from excision of a carotid body tumour is a well-recognised and inherent potential risk of such surgery and Professor A handled this complication in an appropriate and timely manner. Although questioning the need for three periods of carotid clamping, it was felt that the total time of potential cerebral ischaemia was relatively short and the alternative approach of arterial shunting carried its own additional risks. 

Postoperatively, Miss C initially appeared neurologically intact and experts therefore felt that the stroke had occurred several hours after surgery, as the result of thrombus formation at the site of the carotid arterial repair and/or the site of clamp application. It was also agreed that while anti-coagulation may have prevented thrombus formation, such a strategy would have carried a high risk of major haemorrhage and was contraindicated.

The experts raised concerns regarding the failure of the nursing staff to inform the medical team immediately when Miss C demonstrated neurological deterioration. Dr B was also criticised for not performing a full neurological evaluation and wrongly attributing the decreased conscious level simply to opiate toxicity. It was speculated that the resulting delay in the diagnosis and treatment of Miss C’s stroke may have led to a worse neurological outcome.

However, the main focus of criticism centred on the consent process. Experts questioned why Professor A carried out surgery the day after the initial consultation, given the slow growing nature of carotid body tumours. Miss C’s family felt the process had been rushed and that she had not fully understood the magnitude of the risks of surgery. 

Indeed, there was no documented evidence that any of the major complications had ever been discussed and Professor A accepted that the process of informed consent had been inadequate. 

The case was settled for a high sum, reflecting the severe neurological outcome and the need for continuous care.