With a strict protocol during general anesthesia or conscious sedation, decreases in BP did not affect early neurological improvement or long-term functional recovery.
Periprocedural drops in blood pressure (BP) are not associated with worse functional outcomes in patients undergoing mechanical thrombectomy for ischemic stroke, according to a post hoc analysis of the SIESTA trial, in which a strict sedation protocol that avoided BP extremes was used.
Based on the parameters used in the study, Silvia Schönenberger, MD (Heidelberg University, Germany), and colleagues suggest that a target systolic BP range from 140 to 160 mm Hg during thrombectomy is “reasonable and safe.” However, they note that “it is still possible that sedation management without strict BP target ranges may result in less favorable long-term functional outcomes, particularly if collateralization is otherwise compromised. Hence, BP drops during [mechanical thrombectomy] should still be avoided.”
Schönenberger and colleagues conducted the post hoc analysis of data from 150 patients enrolled in SIESTA, a single-center, randomized trial of general anesthesia compared with conscious sedation during thrombectomy. Results of the primary analysis of SIESTA showed no significant difference between groups in early neurological improvement.
No Associations Found
For the post hoc analysis, BP measurements were divided into four groups: preintervention, prerecanalization, postrecanalization, and postintervention. The results were published online May 2, 2018, in Stroke.
No association was found between BP drops during the procedure and change in modified Rankin Scale score at 3 months. In addition, there was no association between the difference in systolic BP, diastolic BP, and mean arterial pressure from baseline to the examined phases of intervention and change in National Institutes of Health Stroke Scale (NIHSS) score after 24 hours. Only baseline diastolic BP in the prerecanalization phase was associated with reduced improvement in NIHSS score (P < 0.01).
Comparing the two types of sedation, baseline mean arterial pressure preintervention was significantly associated with less change in 24-hour NIHSS score in the conscious sedation group (P < 0.01). Consistent with the results of the primary analysis, there was no association between differences in any of the BP values and change in 24-hour NIHSS score, or long-term functional outcomes, in the general anesthesia or conscious sedation groups when analyzed separately.
Importance of Strict BP Protocols
According to Schönenberger and colleagues, there has been a lack of research looking at the effect of peri-interventional BP management on functional outcome before, during, and after thrombectomy. Although some research has suggested that the sedation method may affect outcomes, few studies have looked at peri-interventional BP management.
“Neither the SIESTA trial nor the two recent randomized controlled trials (ANSTROKE [Sedation Versus General Anesthesia for Endovascular Therapy in Acute Stroke] and GOLIATH [General or Local Anesthesia in Intra Arterial Therapy]) . . . investigating the optimal peri-interventional management and monitoring, including strict protocols on BP management, have reported a negative impact of [general anesthesia] on functional outcome after thrombectomy,” the researchers write.
However, they note several limitations of their study, including that it was a single-center analysis with a relatively small sample size and that baseline BP values were based on only a single measurement, which could be prone to errors.
Sources:
Schönenberger S, Uhlmann L, Ungerer M, et al. Association of blood pressure with short- and long-term functional outcome after stroke thrombectomy: post hoc analysis of the SIESTA trial. Stroke. 2018;Epub ahead of print.
