The effect of procedural end-tidal CO2 on infarct expansion during anterior circulation thrombectomy

Abstract

Background Carbon dioxide is a potent cerebral vasodilator that may influence outcomes after ischemic stroke. The objective of this study was to investigate the effect of intraprocedural mean end-tidal CO2 (ETCO2) levels on core infarct expansion and neurologic outcome following thrombectomy for anterior circulation ischemic stroke. Methods A retrospective review was conducted of consecutive patients from March 2020 to June 2021 who underwent mechanical thrombectomy for acute anterior circulation ischemic stroke under general anesthesia and achieved successful recanalization (Thrombolysis in Cerebral Infarction [TICI] ≥ 2b). Only patients with CT perfusion, procedural ETCO2, and postoperative MRI data were included. Segmentation software was used for multi-parametric image analysis. Normocarbia defined as mean ETCO2 of 35 mmHg was used to dichotomize subjects. Univariate and multivariate statistics were applied. Results Fifty-eight patients met criteria for analysis. Of these, 44 had TICI 3 recanalization, 9 had TICI 2c, and 5 had TICI 2b. Within this combined recanalization group, patients with mean ETCO2 > 35 had significantly higher rates of functional independence at 90 days. Although patients tended to salvage more penumbra and experience smaller final infarcts when ETCO2 exceeded 35 mmHg, this did not reach statistical significance. Conclusions Stroke patients who underwent successful thrombectomy with general anesthesia achieved higher rates of functional independence when procedural ETCO2 exceeded 35 mmHg. Further studies to confirm this effect and investigate optimal ETCO2 parameters should be considered.

Ventilation Targets for Patients Undergoing Mechanical Thrombectomy for Acute Ischemic Stroke: A Systematic Review

“…Although the data also showed that patients with mean ETCO 2 greater than 35 mmHg had smaller final infarct volumes and percentages of penumbra that progressed to infarction, this did not reach statistical significance. The main limitations of this study were its retrospective design, the small sample size, and being performed in a single center [14].…”

“…Parr et al, 2022 [14] This was a retrospective study that aimed to investigate the effect of the intraprocedural mean ETCO 2 levels on the core infarct expansion and neurologic outcome following MT for AIS in the anterior circulation under GA. The study included 58 consecutive patients who achieved successful recanalization and had CT perfusion, procedural ETCO 2 , and postoperative MRI data.…”