ABSTRACT
Background: Reports of thrombosis post COVID-19 mRNA vaccination have sparked concerns about safety. Aim(s): We prospectively evaluated blood samples of 18 participants who had received 2 doses of the BNT162b2 mRNA vaccine to determine if vaccination results in endothelial activation or hypercoagulability. Method(s): 18 participants who received the BNT162b2 vaccine were enrolled. Participants completed a questionnaire on their cardiovascular and thrombotic risk factors. Blood samples were collected at three time points: Pre-vaccination (day of vaccination), a median of 17 (IQR 16-18) days after the first dose and a median of 9 (IQR 7.5-14.5) days after the second dose of BNT162b2 vaccine. Endothelial markers included ICAM-1, VCAM-1 and P-selectin. Coagulation tests included PT and aPTT with clot waveform analysis, von Willebrand factor levels, Factor VIII and D-dimer levels. Statistical tests of association between endothelial and coagulation parameters were performed with repeated measures ANOVA and Mauchly's test of sphericity. Result(s): The median age of the participants was 35 years (IQR 31 -44), and 14 (78%) were female. 15 did not have any cardiovascular risk factors. There was a statistically significant increase in median ICAM levels post first (66.1ng/ml) and second dose of vaccination (69.5ng/ml)(p = 0.04), although this remained within the normal limit of ICAM levels. A statistically significant decrease in median PT (p = 0.005) and aPTT (p = 0.03) was observed post vaccination, with a corresponding statistically significant increase in aPTT clot waveform analysis (CWA) for maximum acceleration (max2)(p = 0.03) and maximum deceleration (max2)(p = 0.04) post first and second dose of vaccination. However, all evaluated endothelial and coagulation parameters remain within the reference ranges (Table 1). Conclusion(s): Our findings provide reassuring preliminary data that BNT162b2 vaccination does not result in endothelial activation or hypercoagulability. Mild variations in endothelial markers and coagulation parameters, though statistically significant, remain within the reference ranges and may be related to an inflammatory immune response to vaccination. (Table Presented).
ABSTRACT
Background : Critically-ill COVID-19 patients demonstrate a hypercoagulable state, hence necessitating thromboprophylaxis. However, in non-critically ill COVID-19 patients, the haemostatic profile is unknown. Aims : A prospective, observational study was performed to evaluate coagulation parameters, and thrombotic outcomes in critically and non-critically ill COVID-19 patients. Methods : Informed consent was obtained from 10 critically ill (oxygen dependent, PaO2/FiO2 ratio<300) PCR positive COVID-19 patients matched for age and gender with 10 non-critically ill patients (nonoxygen dependent). On recruitment, laboratory (FBC/LDH/CRP/ procalcitonin) and coagulation tests (PT/APTT/D-Dimer/Fibrinogen/ TCT/Factors II,V,VII,VIII,IX,X,XI/vWF/anti-thrombinIII/ProteinC/ ProteinS/antiphospholipid antibodies), Thromboelastography(TEG), Clot Waveform Analysis(CWA) were performed, with repeat TEG/ CWA every 3 days, till 21 days of admission or discharge. This study was DSRB approved and supported by an NHG-NCID grant. Results : The median age was 60 years(49.5, 64.5) with 16 males and 4 females. Median Padua score of critically ill patients was 5 with PaO2/FiO2 ratio 194.5 (174, 241). Hypercoagulability was present in critically ill patients with elevated median levels of Fibrinogen 5.6 g/L(4.9, 6.6), D-dimer 1.0 μg/ml(0.6, 1.4), Factor VIII 206%(171, 230), von Willebrand Factor 265%(206, 321) as compared with lower levels in non-critically ill patients. Hypercoagulability was shown in TEG with increased CRT Angle 78.9°(78.3, 80.0), CFF MA 34.6 mm(27.4, 38.6) and CFF A10 30.9 s (25.5, 34.0);and CWA had increased clot velocity, aPTT Min1 7.7%/s(6.4, 8.3). CK K, CK Angle, CK MA, CRT MA were higher in critically ill patients (Table 1). In noncritically ill patients, D-dimer levels were normal, 0.3 μg/mL(0.3, 0.4) while Factor VIII levels of 176%(157, 192) and vWF levels of 225%(158, 237) were mildly elevated, with TEG and CWA demonstrating no hypercoagulability. 2 critically-ill patients developed thromboembolism(stroke, DVT) while no non-critically ill patients (not on thromboprophylaxis) had thrombosis. Conclusions : Critically ill COVID-19 patients demonstrate a hypercoagulable state with raised fibrinogen and Factor VIII levels correlating with raised CK, CRT, CFF maximal amplitude and increased CWA clot velocity(min1), while non-critical patients showed an absence of hypercoagulability in global tests of haemostasis.
ABSTRACT
Purpose: The purpose of this paper is to examine student engagement in learning amid COVID-19 and compare it with the previous cohort under face-to-face learning and propose a series of learning activities to engage students for any uncertain situations in the future. Design/methodology/approach: Two online surveys were conducted at the end of the academic years of 2018/2019 and 2019/2020 to measure student engagement under face-to-face tradition learning and emergency remote learning respectively. Findings: Student behavioural engagement was found no statistical difference between the two learning situations, whereas students having face-to-face learning demonstrated greater emotional and cognitive engagement. Social interaction is essential to drive student engagement in emergency remote learning. Practical implications: The authors intended to highlight some teaching approaches and learning activities for social interaction to engage students. Originality/value: Engaging students in remote or online learning is an educational challenge for the new reality. This paper proposed the teaching approach and learning activities to engage students in their learning in the future. © 2021, Emerald Publishing Limited.