A Clinical Update on Antiplatelet Therapy in Secondary Prevention of Ischemic Stroke.

PURPOSE OF REVIEW: Antiplatelet therapy remains the standard of care in secondary stroke prevention for non-cardioembolic ischemic stroke and transient ischemic attack. We aim to examine the use of antiplatelet agents in secondary prevention through highlighting relevant clinical trials and meta-analyses as well as providing commentary regarding our practice. RECENT FINDINGS: In the POINT and CHANCE trials, dual antiplatelet therapy reduced recurrent stroke compared to aspirin monotherapy. Sub-analyses of these trials suggest that genetic polymorphisms could play a role in diminishing the effectiveness of clopidogrel. Similarly, THALES demonstrated better outcomes with ticagrelor-aspirin combination therapy over aspirin monotherapy. Combination antiplatelet therapy with aspirin and the P2Y12 inhibitors, clopidogrel and ticagrelor, reduced stroke recurrence in those presenting with mild ischemic stroke or high risk TIA. Genetic polymorphisms may play a role in determining the appropriate regimen. Questions remain regarding the optimal duration of combination antiplatelet therapy for various stroke etiologies.

Impact of a Guideline for the Management of Antimicrobial/Warfarin Interactions in the Inpatient Setting and Across Transition of Care.

BACKGROUND: Drug-drug interactions (DDIs) with warfarin and antimicrobial agents are a common cause of international normalized ratio (INR) instability, which can affect the risk for bleeding and thrombotic events. OBJECTIVE: The purpose of this study was to assess the impact of a comprehensive guideline for the management of warfarin-antimicrobial DDIs across transitions of care. The guideline emphasizes improving identification of significant antimicrobial-warfarin DDIs during hospitalization, empirical warfarin dose modification based on DDI and baseline INR, patient education, documentation of the DDI, communication with outpatient providers regarding the DDI and anticipated antimicrobial stop date, and warfarin dose adjustment on discontinuation of antimicrobial. METHODS: This retrospective, single-center, quasiexperimental, pre-post study compared end points 3 months before and after guideline implementation. The primary outcome was time within therapeutic range (TTR). RESULTS: The study included 78 preguideline and 31 postguideline patients; baseline characteristics were similar between groups. Implementation of the guideline resulted in greater in-hospital TTR (72% vs 50%, P = 0.04) and improved TTR across transition of care (70% vs 46%, P = 0.01). Documentation of DDI in the pharmacy anticoagulation discharge summary significantly improved in the postguideline group (40% vs 14%, P = 0.02) and numerically improved within the daily pharmacy progress notes (94% vs 82%, P = 0.13). The implementation of the guideline was associated with a nonsignificant, numerical reduction in bleeding events compared with the preguideline group (0 vs 4 events, P = 0.11). CONCLUSION: This single-center approach to optimize the comprehensive management of significant antimicrobial-warfarin DDIs resulted in improved communication with outpatient providers and improved INR TTR.

Evaluation of the Use of Phenobarbital and Benzodiazepines in the Management of Alcohol Withdrawal Syndrome in Patients Requiring Neurological/Neurosurgical Critical Care: A Propensity-Matched Analysis.

Objective There is growing interest in the use of phenobarbital for alcohol withdrawal syndrome in critically ill patients, though experience in neurologically injured patients is limited. The purpose of this study was to compare the safety and effectiveness of phenobarbital-containing alcohol withdrawal regimens versus benzodiazepine monotherapy in the neurocritical care unit. Methods We conducted a retrospective cohort study of adult patients admitted to the neurocritical care unit from January 2014 through November 2021 who received pharmacologic treatment for alcohol withdrawal. Treatment groups were defined as benzodiazepine monotherapy versus phenobarbital alone or in combination with benzodiazepines. The primary outcome was the percentage of patients requiring intubation after receiving alcohol withdrawal treatment. Secondary outcomes included all-cause, in-hospital mortality, intensive care unit length of stay, discharge disposition, change in Glasgow Coma Scale (GCS) score, and the use of adjunctive agents. Results We analyzed data from 156 patients, with 77 (49%) in the benzodiazepine group and 79 (51%) in the phenobarbital combination group. The groups were well-balanced for baseline characteristics, though more males (67, 85%) were in the phenobarbital group. Only three (1.9%) patients received phenobarbital monotherapy, and the rest (153, 98.1%) received combination therapy. The percentage of patients requiring mechanical ventilation was significantly higher in the phenobarbital combination group compared to benzodiazepine monotherapy (39% (n=31) versus 13% (n=10); OR: 4.33, 95% CI: 1.94-9.66; p<0.001). The use of adjunctive propofol and dexmedetomidine was higher in the phenobarbital group (propofol 35% (n= 28) versus 9% (n=7) and dexmedetomidine 30% (n=24) versus 5% (n=4), respectively). Patients in the phenobarbital group also had lower GCS scores and higher Clinical Institute Withdrawal Assessment of Alcohol (CIWA-Ar) scores during their intensive care unit admission, possibly suggesting more severe alcohol withdrawal. There was no difference in intensive care unit length of stay, all-cause, in-hospital mortality, discharge disposition, or therapeutic adjuncts. Conclusions Combination therapy of phenobarbital plus benzodiazepines was associated with higher odds of requiring mechanical ventilation. Few patients received phenobarbital monotherapy. Additional studies are needed to better compare the effects of phenobarbital monotherapy versus benzodiazepines in neurocritical patients.

Ezrin phosphorylation on tyrosine 477 regulates invasion and metastasis of breast cancer cells.

BACKGROUND: The membrane cytoskeletal crosslinker, ezrin, a member of the ERM family of proteins, is frequently over-expressed in human breast cancers, and is required for motility and invasion of epithelial cells. Our group previously showed that ezrin acts co-operatively with the non-receptor tyrosine kinase, Src, in deregulation of cell-cell contacts and scattering of epithelial cells. In particular, ezrin phosphorylation on Y477 by Src is specific to ezrin within the ERM family, and is required for HGF-induced scattering of epithelial cells. We therefore sought to examine the role of Y477 phosphorylation in ezrin on tumor progression. METHODS: Using a highly metastatic mouse mammary carcinoma cell line (AC2M2), we tested the effect of over-expressing a non-phosphorylatable form of ezrin (Y477F) on invasive colony growth in 3-dimensional Matrigel cultures, and on local invasion and metastasis in an orthotopic engraftment model. RESULTS: AC2M2 cells over-expressing Y477F ezrin exhibited delayed migration in vitro, and cohesive round colonies in 3-dimensional Matrigel cultures, compared to control cells that formed invasive colonies with branching chains of cells and numerous actin-rich protrusions. Moreover, over-expression of Y477F ezrin inhibits local tumor invasion in vivo. Whereas orthotopically injected wild type AC2M2 tumor cells were found to infiltrate into the abdominal wall and visceral organs within three weeks, tumors expressing Y477F ezrin remained circumscribed, with little invasion into the surrounding stroma and abdominal wall. Additionally, Y477F ezrin reduces the number of lung metastatic lesions. CONCLUSIONS: Our study implicates a role of Y477 ezrin, which is phosphorylated by Src, in regulating local invasion and metastasis of breast carcinoma cells, and provides a clinically relevant model for assessing the Src/ezrin pathway as a potential prognostic/predictive marker or treatment target for invasive human breast cancer.

Use of intubation introducers through a supraglottic airway to facilitate tracheal intubation: a brief review.

PURPOSE: This article is a narrative review regarding the usage and effectiveness of introducers or catheters to facilitate tracheal intubation through a supraglottic airway (SGA) as an alternative intubation technique in normal and difficult airway management. SOURCES: Relevant articles were obtained through Medline (1948-July 2011). The articles were subsequently cross-referenced for additional literature, and only articles published in English were included. PRINCIPAL FINDINGS: In this review, we consider 32 reports using the LMA Classic™, LMA Unique™, LMA ProSeal™, LMA Supreme™, AuraOnce™, and i-gel™ as SGA conduits for intubation. In 13 articles, the use of an Aintree Intubation Catheter was described as an intubation introducer and resulted in high success rates in both elective and emergent situations. Eight studies used a guidewire exchange catheter technique. Although blind intubation using a guidewire resulted in a high failure rate, these studies found that using a bronchoscope improved successful intubation. Ten studies showed that insertion of a gum elastic bougie with a bronchoscope as an intubation introducer has high success rates compared with blind bougie insertion. One article described the use of a small endotracheal tube as an intermediary for tracheal intubation. CONCLUSIONS: In failed intubation scenarios, supraglottic airways, such as the LMA Classic™ or LMA ProSeal™ can serve as a conduit for tracheal intubation. A number of techniques using introducers or catheters can facilitate the insertion of an adequately sized endotracheal tube, particularly guided by a bronchoscope. Usage of introducers or catheters through a supraglottic airway may be a useful alternative intubation technique in difficult airway management.

Effect of bodyweight on VerifyNow Aspirin platelet function test: a retrospective review.

BACKGROUND: Antiplatelet therapy is used to prevent stent thrombosis in intracranial stents, but the optimal dose of aspirin is unknown. This study sought to determine whether the degree of platelet inhibition with aspirin is affected by bodyweight as observed through a platelet reactivity assay. METHODS: This is a retrospective review of patients who underwent neurovascular stent placement and had a VerifyNow Aspirin assay result. The primary outcome was the correlation between the VerifyNow Aspirin result, bodyweight, and the initial dose of aspirin. Secondary outcomes included the impact of the VerifyNow P2Y12 result and of weight on the incidence of bleeding or a thrombotic event. RESULTS: Of the 142 included patients, 62.7% weighed ≥70 kg and 88.7% were initiated on aspirin 300-325 mg daily. 83.8% achieved a therapeutic VerifyNow Aspirin result. There was minimal correlation between the VerifyNow Aspirin result, bodyweight, and aspirin dose (R2=0.02). Between patients who weighed <70 kg versus ≥70 kg, there was no difference in the mean aspirin reaction units (ARU) (449 vs 435, p=0.32) or in the incidence of bleeding (28% vs 17.1%, p=0.14) or a thrombotic event (4% vs 5.3%, p=0.59). No patient experienced stent thrombosis and eight patients experienced in-stent stenosis. In a multivariate analysis, only the VerifyNow P2Y12 result predicted the development of either bleeding or a thrombotic event (p<0.01). CONCLUSIONS: Bodyweight did not influence the likelihood of obtaining a therapeutic VerifyNow Aspirin result. The clinical utility of obtaining VerifyNow Aspirin assays for this patient population is unknown.