Perioperative stroke: an update

Perioperative stroke: an update

This refresher course session was delivered during Sunday’s sessions at Euroanaesthesia, by Professor Idit Matot, Chair, Division of Anesthesia & Intensive Care & Pain, Tel Aviv Medical Center, Israel, President of the Israel Society of Anesthesiologists, and Elected Chair of the Scientific Committee for ESA.

“Perioperative stroke in patients undergoing non-cardiac, non-carotid operations, although relatively rare (~0.1%), is a devastating complication with remarkable morbidity and mortality,” explained Prof Matot.  “It occurs mostly in the immediate postoperative period and in most cases it is of ischaemic (not haemorrhagic) origin. Patients with previous stroke, or those with atrial fibrillation, history of cardiac disease, renal dysfunction or hypercoagulable states are more prone to perioperative stroke.”

Advanced age is also a risk factor and a recent paper reported higher incidence in patients with patent foramen ovale. Interestingly, a study that involved approximately 2000 patients found no association between the presence of any significant carotid artery stenosis and in hospital stroke or 30 day all-cause mortality, suggesting that high-grade carotid stenosis, at least in the absence of symptoms, does not predict increased perioperative stroke risk and thus should not lead to preoperative revascularisation. .

Professor Matot asked: “Are there any modifiable risk factors that may allow us with careful preoperative management to reduce the incidence of stroke? The answer is yes. In patients with a history of stroke in need of elective surgery, waiting for at least 6 months or even better for 9 months will lower the perioperative stroke rate.”

She added: “Also, avoiding the administration of beta blockers in patients naïve to this medication the day before surgery will reduce the risk. Physicians should also consider discontinuation of ACE inhibitor/angiotensin II receptor blocker prior to surgery. Although intraoperative hypotension is associated with postoperative acute kidney injury and myocardial injury, its effect on the brain is less conclusive.”

The topic of whether or not to bridge before surgery with short acting anticoagulants during anticoagulantion interuptions in patients at high risk for thromboembolism was also covered in this comprehensive session. Prof Matot said: “The current data suggest that where there is low or moderate thrombotic risk, there is no evidence that bridging with anticoagulants is beneficial in reducing thromboembolic events. On the contrary, it may be harmful as it leads to more bleeding, and consequently complications.”

As patients in the postoperative period are obviously hospitalised, in the case of an acute stroke it is reasonable to believe that the event to endovascular treatment time will be short. This is not the case, however, because the awareness that stroke might develop in the postoperative patient undergoing non-cardiac / non-carotid surgery is low and delayed symptom recognition is almost the rule. Prof Matot explained that it is thus of utmost importance to discuss and look for this complication in the PACU and on the ward to increase awareness.

She said: “Once stroke is diagnosed, a neurology consultation, activation of the stroke team, getting the patient to the imaging suit while keeping normoglycemia, normothermia, normocarbia, well oxygenated and systolic blood pressure between 140-180 mmHg is of utmost importance. The faster an eligible patient is revascularised, the better the prognosis. Nevertheless, recent studies suggest that endovascular procedure might still be beneficial up to 16 hours, or even 24 hours, from the event when imaging shows brain tissue at risk but salvageable. Whether to perform the procedure under sedation or general anaesthesia is debatable. Recent randomised studies did not document any benefit from the use of conscious sedation but rather found better functional outcome with general anaesthesia.”