Campbell, B. C.V. et al. (2019) Penumbral imaging and functional outcome in patients with anterior circulation ischaemic stroke treated with endovascular thrombectomy versus medical therapy: a meta-analysis of individual patient-level data.ABSTRACT Background: CT-perfusion (CTP) and MRI may assist patient selection for endovascular thrombectomy. We aimed to establish whether imaging assessments of ischaemic core and penumbra volumes were associated with functional outcomes and treatment effect.

Campbell, B. C. V. et al. (2018) Effect of general anaesthesia on functional outcome in patients with anterior circulation ischaemic stroke having endovascular thrombectomy versus standard care: a meta-analysis of individual patient data. Lancet Neurology, 17(1), pp. 47-53. (doi:10.1016/S1474-4422(17)30407-6) This is the author's final accepted version.There may be differences between this version and the published version. You are advised to consult the publisher's version if you wish to cite from it.http://eprints.gla.ac.uk/149670/ variables. An alternative approach using propensity-score stratification was also used. To account for between-trial variance we used mixed-effects modeling with a random effect for trial incorporated in all models. Bias was assessed using the Cochrane tool.Findings: Of 1764 patients in 7 trials, 871 were allocated to endovascular thrombectomy. After exclusion of 74 patients (72 who did not undergo the procedure and 2 with missing data on anaesthetic strategy), 236/797 (30%) of endovascular patients were treated under GA. At baseline, GA patients were younger and had shorter time to randomisation but similar pre-treatment clinical severity compared to non-GA. Endovascular thrombectomy improved functional outcome at 3 months versus standard care in both GA (adjusted common odds ratio (cOR) 1·52, 95%CI 1·09-2·11, p=0·014) and non-GA (adjusted cOR 2·33, 95%CI 1·75-3·10, p<0·001) patients. However, outcomes were significantly better for those treated under non-GA versus GA (covariate-adjusted cOR 1·53, 95%CI 1·14-2·04, p=0·004; propensitystratified cOR 1·44 95%CI 1·08-1·92, p=0·012). The risk of bias and variability among studies was assessed to be low.Interpretation: Worse outcomes after endovascular thrombectomy were associated with GA, after adjustment for baseline prognostic variables. These data support avoidance of GA whenever possible. The procedure did, however, remain effective versus standard care in patients treated under GA, indicating that treatment should not be withheld in those who require anaesthesia for medical reasons. Funding:The HERMES collaboration was funded by an unrestricted grant from Medtronic to the University of Calgary. Research in contextEvidence before this study between abolition of the thrombectomy treatment effect in MR CLEAN and no effect in THRACE. Three single-centre randomised trials of general anaesthesia versus conscious sedation found either no difference in functional outcome between groups or a slight benefit of general anaesthesia. Added value of this studyThese data from contemporary, high quality randomised trials form the largest study to date of the association between general anesthesia and the benefit of endovascular thrombectomy versus standard care. We used two different approaches to adjust for baseline imbalances (multivariable logistic regression and propensity-score stratification). We found that GA for endovascular thrombectomy, as practiced in contemporary clinical care across a wide range of expert centres during the rand...

During hemodialysis a decrease in pulmonary ventilation has been reported. The elimination of CO₂ across the dialyzer has been suggested as the cause of the pulmonary hypoventilation. Our purpose was to analyze the factors that could have influenced the pulmonary ventilation of 7 patients with chronic renal failure during hemodialysis, performed against an acetate dialysate with constant addition of CO₂, bubbling into the dialysis bath. In spite of the large volume of CO₂ mainly as bicarbonate, eliminated across the dialyzer there was no significant decrease of ventilation. The values of pH in the venous line were extremely low and the values of P_vCO₂ were artificially maintained around 35.0 mm Hg. Thus, the total CO₂ delivered to the lungs, but mainly the levels of pH and PCO₂ in the venous line play an important role in the control of pulmonary ventilation of these patients.

The elimination of CO₂ across the dialyzer has been reported as the cause of the pulmonary hypoventilation during hemodialysis. There are some evidences that the venous line blood composition could influence the central venous blood and this one the pulmonary ventilation. Our purpose was to analyze (1) the influence of the changes in composition of the venous line blood on the central venous blood and (2) the possible role of the central venous blood composition on the pulmonary ventilation of 10 chronic renal failure patients during hemodialysis performed twice in the same patients in two different conditions: acetate dialysate without (condition I) and with (condition II) constant addition of 100% CO₂ bubbling into the dialysis bath. During condition I the venous line blood pH was kept in a normal range, and the PCO₂ was low, whereas during condition II the pH was very low and the PCO₂ extremely high. The patients during condition I decreased their pulmonary ventilation and lost CO₂ across the dialyzer as the central venous blood pH and HCO^-₃ increased, and PCO₂ did not change. The same patients during condition II increased their pulmonary ventilation and absorbed CO₂ across the dialyser as the central venous blood pH decreased and PCO₂ increased. Thus, the venous line blood has influence on the central venous blood composition, and this plays a role on the control of pulmonary ventilation of these patients.