A 10% blood pressure drop from baseline during mechanical thrombectomy for stroke is strongly associated with worse neurological outcomes

Abstract

BackgroundMechanical thrombectomy (MT) for acute ischemic stroke can be performed under local anesthesia, with or without conscious sedation (CS), or under general anesthesia (GA). The hemodynamic consequence of anesthetic drugs may explain why GA may be associated with worse outcomes. We evaluated the association between hypotension duration during MT and the 90 day functional outcome under both anesthetic regimens.MethodsPatients were included in this retrospective study if they had an ischemic stroke treated by MT under GA or CS. The main exposure variable was the time below 90% of the reference value of arterial pressure measured before MT. The primary outcome was poor functional outcome defined as a 90 day modified Rankin Score ≥3.Results371 patients were included in the study. GA was performed in 42%. A linear association between the duration of arterial hypotension and outcome was observed. The odds ratio for poor functional outcome of 10 min under 90% of the baseline mean arterial pressure was 1.13 (95% CI 1.06 to 1.21) without adjustment and 1.11 (95% CI 1.02 to 1.21) after adjustment for confounding factors. The functional outcome was poorer for patients treated under GA compared with CS, but the association with the depth of hypotension remained similar under both conditions.ConclusionIn this study, we observed a linear association between the duration of hypotension during MT and the functional outcome at 90 days. An aggressive and personalized strategy for the treatment of hypotension should be considered. Further trials should be conducted to address this question.

Intracranial Hemorrhage After Reperfusion Therapies in Acute Ischemic Stroke Patients

“…sICH rates were not significantly related to baseline systolic or diastolic blood pressure (93). Systolic, pulse pressure and mean arterial BP variability during EVT seem to be critically associated with functional outcome (91,92,(95)(96)(97)(98), but data are scarce regarding the association of blood pressure variability during EVT and sICH risk. After EVT, and notably after complete reperfusion, blood pressure variability seems associated with increased rates of sICH (99,100).…”

Blood Pressure During Endovascular Treatment Under Conscious Sedation or Local Anesthesia

“…Similar, previous studies reported worse functional outcomes in patients with a drop in MAP from baseline of ≥ 10% who received CS or GA during the procedure. 14,19,28 A recent study found that larger AUTs were associated with worse functional outcome in patients receiving GA as well as in patients receiving monitored anesthesia care (MAC), which is a composite of CS and LA. 7 In our study, blood pressure drops were relatively mild, especially in…”

“…Because there is no consensus on which BP-derived measures are most relevant and what should be avoided (e.g., drops, variability), we focused on 3 predefined orthogonal definitions that capture different elements of BP drops and variability 17 : area under the threshold (AUT, with MAP on admission as the threshold determined per patient) in mm Hg*minute, reflecting both the depth and duration of the relative hypotensive episode; the relative difference between the MAP on admission and the lowest MAP during the EVT procedure, expressed as percentage drop in MAP (∆LMAP), to account for shorter, larger BP drops; and the BP trend during the procedure, defined as the slope for each patient derived from a multilevel linear regression model with “time since start procedure” as a predictor, with a random slope to estimate patient-specific trends in BP measurements, for the continuous outcome systolic BP including a random effect for patient to account for within-patient variability ( figure 1 ). 7 , 8 , 18 – 20 Hemodynamic intervention was defined as the administration of any inotropes or vasopressors (e.g., ephedrine, phenylephrine) to increase BP or the use of sympathicolytics (e.g., labetalol, clonidine) to lower BP. BP was regulated according to institutional practices; in general, systolic BP was maintained between 140 and 185 mm Hg with a diastolic BP below 105 mm Hg based on anesthetic critical care recommendations.…”

“…predictor, with a random slope to estimate patient specific trends in blood pressure measurements, for the continuous outcome systolic blood pressure including a random effect for patient to account for within patient variability (Figure 1). 7,8,[18][19][20] Hemodynamic intervention was defined as the administration of any inotropes or vasopressors (e.g. ephedrine, phenylephrine) to increase blood pressure or the use of sympathicolytics (e.g.…”

Blood Pressure Management in Acute Ischemic Stroke

“…A significant BP drop may occur during the induction phase of GA during MT, since a drop in BP is a side effect of most anesthetic medications [96]. However, not only GA but also CS causes a decline in BP [97,98] (see above).…”