Managing and Supporting Surgery in Patients with Bleeding Disorders

Role of Prednisolone in Platelet Activation by Inhibiting TxA2 Generation through the Regulation of cPLA2 Phosphorylation

Glucocorticoids have been commonly used in the treatment of inflammation and immune-mediated diseases in human beings and small animals such as cats and dogs. However, excessive use can lead to Cushing's syndrome along with several thrombotic and cardiovascular diseases. Although it is well-known that glucocorticoids exert a significant effect on coagulation, the effect of cortisol on platelet function is much less clear. Thus, we aimed to study the effects of prednisolone, one of the commonly used glucocorticoids, on the regulation of platelet function using murine platelets. We first evaluated the concentration-dependent effect of prednisolone on 2-MeSADP-induced platelet function and found that the 2-MeSADP-induced secondary wave of aggregation and dense granule secretion were completely inhibited from 500 nM prednisolone. Since 2-MeSADP-induced secretion and the resultant secondary wave of aggregation are mediated by TxA₂ generation, this result suggested a role of prednisolone in platelet TxA₂ generation. Consistently, prednisolone did not affect the 2-MeSADP-induced aggregation in aspirinated platelets, where the secondary wave of aggregation and secretion were blocked by eliminating the contribution of TxA₂ generation by aspirin. In addition, thrombin-induced platelet aggregation and secretion were inhibited in the presence of prednisolone by inhibiting the positive-feedback effect of TxA₂ generation on platelet function. Furthermore, prednisolone completely inhibited 2-MeSADP-induced TxA₂ generation, confirming the role of prednisolone in TxA₂ generation. Finally, Western blot analysis revealed that prednisolone significantly inhibited 2-MeSADP-induced cytosolic phospholipase A₂ (cPLA₂) and ERK phosphorylation in non-aspirinated platelets, while only cPLA₂ phosphorylation, but not ERK phosphorylation, was significantly inhibited by prednisolone in aspirinated platelets. In conclusion, prednisolone affects platelet function by the inhibition of TxA₂ generation through the regulation of cPLA₂ phosphorylation, thereby shedding light on its clinical characterization and treatment efficacy in dogs with hypercortisolism in the future.

Pregnancy, childbirth and neonatal outcomes in women with inherited bleeding disorders: A retrospective analysis

Women with inherited bleeding disorders can deliver without complication when best practices are maintained.

Elective surgery in patients with inherited bleeding disorders: A retrospective analysis

INTRODUCTION

Published guidelines are available to assist in the management of patients with inherited bleeding disorders in the elective surgical setting however good quality outcome data is lacking.

AIM

- Evaluate the outcomes of adult patients with inherited bleeding disorders, who received factor replacement for elective surgery in NSW/ACT, Australia. - Assess adherence to relevant guidelines including Haemophilia Treatment Centre (HTC) utilisation and appropriate factor replacement.

METHOD

A retrospective analysis was performed between 2000 and 2018 to describe patient characteristics, surgical details, factor provision and outcomes. Univariate analysis was used to determine variables associated with guideline adherence. Covariates with p < 0.1 were included in the multivariate analysis.

RESULTS

A total of 1065 surgeries were performed on 571 patients. Diagnoses included Haemophilia A (43.5%), Haemophilia B (9.7%), von Willebrand disease (VWD) (45.3%) and rare bleeding disorders (RBDs) (1.6%). Bleeding complications were reported in 14 surgeries and 19 patients received factor replacement beyond standard duration of prophylaxis. Approximately 50% of all surgeries were performed in a HTC. Multivariate analysis demonstrated that diagnosis, surgical specialty, sex and year (p < 0.001) were associated with non-compliance with variable pattern within each category. Factor replacement was as expected except for plasma-derived Factor VIII/VWF usage in patients with VWD undergoing major bleeding risk surgery. VWD classification (p < 0.001) was associated with this deviation.

CONCLUSION

Low complication rates demonstrate that elective surgery in Australia is being safely performed in patients with inherited bleeding disorders however non-compliance with published guidelines exists highlighting areas of practice and policy discrepancies that warrant further exploration.