Cocaine Use is Associated with More Rapid Clot Formation and Weaker Clot Strength in Acute Stroke Patients.

INTRODUCTION: 1.1.Cocaine use is a known risk factor for stroke and has been associated with worse outcomes. Cocaine may cause an altered coagulable state by a number of different proposed mechanisms, including platelet activation, endothelial injury, and tissue factor expression. This study analyzes the effect of cocaine use on Thrombelastography (TEG) in acute stroke patients. PATIENT AND METHODS: 1.2.Patients presenting with Acute Ischemic Stroke (AIS) and spontaneous Intracerebral Hemorrhage (ICH) to a single academic center between 2009 and 2014 were prospectively enrolled. Blood was collected for TEG analysis at the time of presentation. Patient demographics and baseline TEG values were compared between two groups: cocaine and non-cocaine users. Multivariable Quantile regression models were used to compare the median TEG components between groups after controlling for the effect of confounders. RESULTS: 1.3.91 patients were included, 53 with AIS and 38 with ICH. 8 (8.8%) patients were positive for cocaine, 4 (50%) with AIS, and 4 (50%) with ICH. There were no significant differences in age, blood pressure, platelet count, or PT/PTT between the cocaine positive and cocaine negative group. Following multivariable analysis, and adjusting for factors known to influence TEG including stroke subtype, cocaine use was associated with shortened median R time (time to initiate clotting) of 3.8 minutes compared to 4.8 minutes in non-cocaine users (p=0.04). Delta (thrombin burst) was also earlier among cocaine users (0.4 minutes) compared with non-cocaine users (0.5 min, p=0.04). The median MA and G (measurements of final clot strength) were reduced in cocaine users (MA=62.5 mm, G=7.8 dynes/cm2) compared to non-cocaine users (MA=66.5 mm, G=10.1 dynes/cm2; p=0.047, p=0.04, respectively). CONCLUSION: 1.4.Cocaine users demonstrate more rapid clot formation but reduced overall clot strength based on admission TEG values

Dual Antiplatelet Therapy Is Associated With Coagulopathy Detectable by Thrombelastography in Acute Stroke.

BACKGROUND: Thrombelastography (TEG) provides a global, dynamic measure of coagulation. We examined the effect of antiplatelet (AP) medications on coagulation in patients with acute stroke as measured by TEG. METHODS: We reviewed prospectively collected data on patients presenting with acute ischemic stroke (AIS) and spontaneous intracerebral hemorrhage (ICH) between 2009 and 2014. Patient demographics and baseline TEG values were compared among 4 different drug use groups: aspirin only, clopidogrel only, both aspirin and clopidogrel, and no AP. Multivariable regression models were conducted to compare the differences in TEG components. RESULTS: A total of 202 patients were included, 139 with AIS and 63 with ICH. Forty-eight (24%) patients were taking aspirin alone, 12 (6%) were taking clopidogrel, 16 (8%) dual AP, and 126 (62%) no AP. Dual AP use was associated with prolonged mean R (time to initiate clotting) of 5.5 minutes as compared to no AP use (4.6 minutes, CONCLUSION: Dual AP therapy is associated with a detectable coagulopathy which may have implications in the management of patients with AIS and hemorrhagic stroke. The effects of single AP therapy may not be demonstrated by TEG

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population