Cytoprotective Agents in Stroke: Still Uncertainty in the Next Frontier.

INTRODUCTION: Despite substantial improvement of acute ischemic stroke (AIS) care with the advent of extended time windows for intravenous thrombolysis (IVT) and endovascular thrombectomy (EVT), a substantial portion of patients still suffer poor outcomes. Additional adjuvant therapies are needed but pharmacologic interactions among therapies may dictate how they could be used. We conducted a survey to determine physician decision-making regarding the use of cytoprotective agents in patients presenting with AIS. METHODS: The survey was structured, web-based, anonymous, and invite-only among physicians across the world treating patients presenting with AIS. Respondents were asked about the use of a hypothetical cytoprotective agent (that provided an added 10% benefit) in the context of a treatment interaction with IVT or its timing in relation to IVT. RESULTS: A total of 282 stroke physicians (74.9% males, mean age 46 years) participated in the survey. When the respondent could give both the cytoprotective agent and IVT with no treatment interaction, 177 (78.0%) chose to administer both. In the presence of treatment interaction, 88 (38.3%) would withhold IVT, 83 (36.1%) would withhold the cytoprotective agent and 56 (24.4%) were uncertain. Lastly, 111 (48.9%) were willing to administer the cytoprotective agent if it meant a necessary 10-minute delay in IVT administration. CONCLUSIONS: Pharmacologic interactions result in major uncertainty about cytoprotective treatment choices.

The effect of burst suppression on cerebral blood flow and autoregulation: a scoping review of the human and animal literature.

Background: Burst suppression (BS) is an electroencephalography (EEG) pattern in which there are isoelectric periods interspersed with bursts of cortical activity. Targeting BS through anaesthetic administration is used as a tool in the neuro-intensive care unit but its relationship with cerebral blood flow (CBF) and cerebral autoregulation (CA) is unclear. We performed a systematic scoping review investigating the effect of BS on CBF and CA in animals and humans. Methods: We searched MEDLINE, BIOSIS, EMBASE, SCOPUS and Cochrane library from inception to August 2022. The data that were collected included study population, methods to induce and measure BS, and the effect on CBF and CA. Results: Overall, there were 66 studies that were included in the final results, 41 of which examined animals, 24 of which examined humans, and 1 of which examined both. In almost all the studies, BS was induced using an anaesthetic. In most of the animal and human studies, BS was associated with a decrease in CBF and cerebral metabolism, even if the mean arterial pressure remained constant. The effect on CA during periods of stress (hypercapnia, hypothermia, etc.) was variable. Discussion: BS is associated with a reduction in cerebral metabolic demand and CBF, which may explain its usefulness in patients with brain injury. More evidence is needed to elucidate the connection between BS and CA.

Treatment of Acute Stroke: Current Practices and Future Horizons.

PURPOSE: This review will discuss revascularization of acute ischemic stroke (AIS), discussing the concept of the ischemic penumbra and how thrombolysis and thrombectomy take advantage of it. SUMMARY: The goal of AIS revascularization is to rescue the ischemic penumbra and the approach to has gone from a time-based to tissue-based approach. Patients must be carefully selected for thrombolysis, which traditionally was limited to those whose last known normal time (LKNT) was known and within 4.5 h. However, newer imaging techniques involving MRI and CT perfusion (CTP) can select patients for thrombolysis whose LKNT is unknown. Alteplase, or tPA, is still the agent of choice for thrombolysis in patients with AIS but tenecteplase (TNK) may be just as effective and more efficient to use. Endovascular thrombectomy (EVT) has shown considerable efficacy for treating large-vessel occlusions and using CTP, patients can be selected for hours after symptom-onset if viable tissue remains. Further research is underway to determine if EVT can be used for medium vessel occlusions and for basilar artery thromboses as well as to determine whether an "EVT-alone" strategy is superior to "tPA + EVT" strategy.

Transfusions in patients with iron deficiency anemia following release of Choosing Wisely Guidelines.

BACKGROUND: In 2016, based on recommendations of the American Association of Blood Banks (AABB), Choosing Wisely Canada released transfusion guidelines for patients with Iron Deficiency Anemia. The goal of the present study was to examine the number of transfusions given in Calgary emergency departments (EDs) before and after the release of these guidelines. METHODS: We analyzed 11,786 anemia encounters from January 2014 to December 2019. A transfusion was considered potentially avoidable if the patient's hemoglobin was > 70 g/L and if the patient was hemodynamically stable. We used time-series analyses to examine change in rate of total and potentially avoidable transfusions quarterly over the total and pre and post intervention periods. RESULTS: In total, 1409/11,786 (12.0%) of the encounters received transfusions; 80.0% (1127/1409) were indicated while 19.9% (281/1409) were potentially avoidable. In the pre-intervention period, the rate of potentially avoidable transfusions was 21.5% (133/618) and in the post-intervention period, the rate of potentially avoidable transfusions was 18.7% (148/791). The rate of potentially avoidable transfusions decreased quarterly at a rate of 0.3% which did not reach statistical significance (p = 0.06). DISCUSSION: Our data suggest that the number of potentially avoidable transfusions has not decreased since the release of Choosing Wisely Canada guidelines and local educational initiatives. This may be due to the fact that there is a pre-existing down trend in the number of transfusions provided.

RéSUMé: CONTEXTE: En 2016, sur la base des recommandations de l'AABB (Association américaine des banques de sang) Choisir avec soin Canada a publié des directives sur la pratique transfusionnelle pour les patients atteints d'anémie ferriprive. Le but de la présente étude était d'examiner le nombre de transfusions administrées dans les services d'urgence (SU) de Calgary avant et après la publication de ces directives. MéTHODES: Nous avons analysé 11 786 cas d'anémie entre janvier 2014 et décembre 2019. Une transfusion était jugée comme potentiellement évitable si l'hémoglobine du patient était > 70 g/L et si le patient était stable sur le plan hémodynamique. Nous avons utilisé des analyses de séries chronologiques pour examiner trimestriellement le changement du taux de transfusions totales et potentiellement évitables au cours de l'ensemble des périodes, y compris avant et après l'intervention. RéSULTATS: Au total, 1409/11786 (12.0%) des cas ont reçu des transfusions ; 80.0% (1127/1409) ont été indiqués tandis que 19.9 % (281/1409) étaient potentiellement évitables. Pendant la période précédant l'intervention, le taux de transfusions potentiellement évitables était de 21.5 % (133/618) et dans la période postérieur à l'intervention, le taux de transfusions potentiellement évitables était de 18,7 % (148/791). Le taux de transfusions potentiellement évitables a diminué chaque trimestre à un taux de 0,3 % qui n'a pas atteint la signification statistique (p = 0,06). DISCUSSION: Nos données suggèrent que le nombre de transfusions potentiellement évitables n'a pas diminué depuis la publication des directives de Choisir avec soin Canada et des initiatives éducatives locales. Cela peut être dû au fait qu'il existe une tendance à la baisse préexistante du nombre de transfusions fournies.