Ciprofol vs Propofol for Hemodynamic Stability in Patients Having General Anesthesia for Endovascular Thrombectomy After Ischemic Stroke: A Multicenter Randomized Open-label Parallel-group Trial (CONSTANCY)

Endovascular therapy (EVT) improves the prognosis of patients with acute ischemic stroke (AIS). EVT has been established as a standard of care for AIS caused with large vessel occlusion based on numerous randomized controlled trials. However, despite extensive attention to post-EVT blood pressure management as a potentially modifiable factor, the ability to achieve high reperfusion rates does not consistently translate into functional independence for a substantial number of patients. Consequently, post-EVT intensive blood pressure lowering has not been recommended. In fact, the ischemic brain prior to reperfusion may be more vulnerable to blood pressure fluctuations due to disrupted microvascular integrity and impaired autoregulation. Thus, the focus has turned to the intra-procedural period, where blood pressure management may play a critical but underexamined role in determining functional outcomes independent of post-EVT care.

Guideline recommendation to maintain the blood pressure lowered to 185/110 mmHg before the EVT procedure in patients who have not received intravenous thrombolysis therapy is based on expert opinion. However, studies of blood pressure before reperfusion in this patient group have produced conflicting results. Multicenter Randomized Controlled Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) registry showed an increase in systolic blood pressure above 150 mmHg before EVT was associated with poor functional outcome and mortality at 90 days, whereas individual patient data meta-analysis found that admission SBP ≥140 mmHg was associated with worse functional outcome, but no such association was observed for SBP <140 mmHg. Furthermore, subgroup analyses of two randomized controlled trials consistently showed that intensive blood pressure lowering before reperfusion was associated with worse functional outcomes. Thus, although randomized trials evaluating pre-thrombectomy blood pressure targets are yet unavailable, accumulating evidence suggests that active blood pressure lowering before reperfusion may be harmful, which underscores the importance of maintaining hemodynamic stability during the EVT procedure.

In this context, anesthetic management is a key determinant of intraprocedural blood pressure control. Propofol is the most commonly used general anesthetic during EVT surgery. However, propofol is a powerful venodilator and often provokes hypotension which may be especially detrimental in AIS patients. Ciprofol, a novel anesthetic/sedative, has been proven to possess excellent efficacy and safety which provides definitive general anesthesia/sedation while minimizing respiratory and hemodynamic depression. Before and during EVT, patients with hemodynamic stability may have better outcomes. Using ciprofol as the anesthesia agent may reduce the incidence and severity of hemodynamic instability during EVT. Therefore, it is of significant research value to investigate whether the use of ciprofol for general anesthesia is beneficial in AIS patients undergoing EVT.