Influence Antiplatelet Therapy Taken - Research Paper Example

Does Anti-platelet Therapy Taken for Coronary Artery Diseases Pre-Operative Lead to Bleeding or Improve Patient Bleeding During Bypass. Name Student Number Institution Course Code Instructor Date Introduction Cardiac surgeries present critical procedures that require stringent evaluations and considerations to ensure benefits and risks are weighed, and impeccable decision made. This is crucial with regard to ensuring that procedures undertaken and therapies administered result to improved recovery with reduced rates of complications or re-operation for corrective purposes. There exist increased controversies pertaining to anticoagulation therapy with cardiac patients scheduled for cardiac surgery. The risk associated with increased bleeding among patients taking anticoagulants or anti-platelet drugs scheduled for cardiac surgery requires a number of measures to ensure balancing of risks with treatment stoppage. Further, the utilization of drugs is paramount in reducing chances of ischemic complications and enhancing patency of grafts in bypass surgery. It is therefore necessary to identify whether antiplatelet therapy taken for coronary artery disease pre-operative lead to bleeding of improves bleeding during bypass procedure. Research Aim: The study aims at having a clear understanding as to how patients taking anti-platelet therapy and scheduled for cardiac surgery will benefit from therapy discontinuation and the level of bleeding involved. Research Question: what is the outcome of patients who are taking dual anti-platelet therapy prophylactically for coronary disease discontinuing it prior to cardiac surgery and the effects in respect to patient bleeding post-operatively? In this context, the dependent variable is bleeding and the independent variables are aspirin and plavix (clopidogrel). Figure 1: Flow Chart: Search Strategy (Source: Author) Critical Review of the Dual Therapy (Aspirin and clopidogrel) Pre-operative Increased controversies surround the management of patients scheduled to undergo a cardiac surgery and taking dual anticoagulants (Dasarathan et al., 2011). This is heighted with respect to cases where combined therapy of anticoagulant is being used by the patient scheduled for cardiac surgery. The need for critical consideration before the actual cardiac surgery and for this study involves coronary artery graft bypass surgery, overview of clinical investigations are necessary to determine the efficacy of the combination of aspiring and plavix (Simon et al., 2013). The need for the analysis ensures that critical evaluations bring to light the benefits, as well as risks associated with the dual therapy and establish their essence pre-operative. According to Calafiore et al. (2010), Aspirin in the dual therapy can be established as the prophylactic anti-platelet drug for majority of patients having cardiovascular disorders and helps in blood thinning to avert cardiac arrest. The utilization of a second anticoagulant is aimed at enhancing the benefits among patients termed as high risk within the cardiac disorder category (Kim et al., 2009). Nevertheless, there exist various dilemmas among clinicians involves the risk of discontinuing therapy which may result to increased rate of ischemic complications or continuation of therapy and risk increased bleeding (Mauri, et al., 2014; Simon et al., 2013; Ferrandis, Llau and Mugarra, 2009; Gao, Ren, Li et al., 2009). Evaluating the chemical operation and benefits of the drug and subsequent risks in respect to bypass surgery pre-operatively will give critical concepts for effective study findings. The pharmacokinetics of aspirin and plavix involves preventing stent thrombosis which involves preventing the blood inside the stent to clot which may bring about heart attack. However, for anticoagulant patients scheduled for cardiac surgery, continuation or discontinuation of the drug therapy presents a critical aspect for consideration to ensure bleeding management during surgery and post-operatively (Fendarris et al., 2009), as well as manage other complications associated with altered therapy. The use of aspirin and clopidogrel is very crucial in the management of heart attack occurrence; however, continuous use of the treatments prior to a cardiac surgery remains unclear of the consequences (Simon, et al., 2013). Studies have come up evaluating the benefits and setbacks associated with utilization of various anticoagualnts in the course of cardiac surgery procedures. Ferrandis et al. (2009) indicates that withdrawal of the drugs has been associated with increased risk of thrombotic event; and further Merriman (2011) asserts that surgery being conducted under an altered platelet function may result to enhanced risk of bleeding during post-operative period. The end result is clinical consideration to establish the right approach for specific case scenarios while evaluating the most effective procedure. The use of dual anticoagulant therapy has its importance with respect to bypass surgery for patients under anti-platelet therapy. Zimmermann, Gams and Hohlfeld (2008) argues that the success of coronary bypass surgery majorly depends upon the patency success of the graft vessels. Thus, any procedure that promotes the patency of bypass is paramount in the entire cardiac surgery. The use of anticoagulants during bypass surgery is critical as argued by Parang and Arora (2009) in that peri-operative anti-platelet therapy can significantly reduce occurrence of early thrombosis and graft failure. On the same note, Kim et al. (2011) support this argument with the study on 220 patients on pre-operative use of aspirin stating that the drug reduces in-hospital mortality without increased level of hemorrhage, necessity for blood products or even related morbidity. Further, Gurbuz et al. (2005) indicates that plavix reduces recurrence of ischemic disorder and enhances stent patency. In context, these arguments clearly indicate the benefits associated with use of aspirin and clopidogrel during cardiac surgery. Dasarathan et al. (2011) concluded in their study that pre-operative exposure of plavix has no influence on the rate of hemostatic re-operation or the need for transfusion after a bypass surgery. Nevertheless, increased blood loss and myocardial infarction is associated with use of clopidogrel and aspirin combined therapy (Miceli et al., 2012). The combined therapy presents a challenge in respect to managing increased blood loss which can be replenished through transfusion with the occurrence of MI. In context, an earlier study by Kim et al. (2009) brings the idea that early use of clopidogrel and aspirin after surgery may be crucial in comparison with pre-operative aspirin therapy alone during a bypass surgery raising the idea of discontinuation and early introduction of therapy after surgery. However, Kim et al. are quick to point of the need for more studies to critically confirm their findings indicating lack of certainty in respect to the findings. Clinicians experience the challenge of navigating the uncertain balance existing between bleeding and clotting during cardiac surgery for patients under anti-platelet therapy. The use of anti-platelet therapy prior to artery surgery critically increases the problem of compromising between treatment discontinuation and management of the treatment process, as well as subsequent bleeding post-operatively. Nevertheless, Sun et al. (2008) argues that use of aspirin pre-operative are unclear but supports that early use of the drug after surgery promotes graft patency, lowers complications of ischemic while at the same time improving survival. In respect to Merriman (2011), patients under aspirin pre-operatively have elevated risks of having post-operative bleeding after cardiac surgery. Further, use of aspirin within seven days of coronary artery bypass has been indicated to result to high levels of blood loss calling for re-operation; nevertheless, this does not contribute to increased mortality. Bleeding is a major consideration in respect heart surgeries with platelet dysfunction and dilution of all components of coagulation system (Milas, Jobes and Gorman, 2000). Exposure to clopidogrel has been indicated by Kremke et al. (2013) to result to increased rates of reoperation associated with increased rates of post-operative hemorrhage. Nevertheless, there are benefits associated with the use of the drug after therapy without the occurrence of hemorrhage under postoperative protocol (Halkos et al., 2006). The dual therapy of plavix and aspirin presents drugs with divergent mechanisms of action but common irreversibility pertaining to inhibition mechanism (Calafiore et al., 2010). In this regard, the concept of dual therapy presents various aspects as indicated with benefits beings evaluated surpassing the increased rate of bleeding due to continuation of the anticoagulants. Ray et al. (2003) indicates that increased anti-platelets administration before cardiac surgery has been associated with high risk of major bleeding. Clopidogrel contains a high incidence of platelet inhibitory irrespective of the level of exposure (Kwa et al., 2011). This indicates that discontinuation of plavix pre-operative will have no greater impact in respect to bleeding since the therapy will have traces in the patient’s system. The use of the two drugs can be incorporated relatively maintaining safety in the pre-operative stage with Cannon et al., 2005) indicating that five days prior to surgery utilization of the dual therapy results to moderate and variable rise in bleeding. This brings up the essence of the dual therapy coupled with the maintenance of graft patency immediately after surgery (Gao et al., 2009). The benefits of combining aspirin with clopidogrel pre-operative indicate an increased need for to tap on the positive outcomes. The administration plavix prior to catherization in bypass graft surgery has been associated with less than 30-day adverse ischemic events and does not elevate bleeding in comparison to withholding it until post-operative stage (Ebrahimi et al., 2009). Further, Gao et al. (2010), assert that the dual therapy of aspirin and plavix is highly effective in graft patency that utilization of aspirin alone. Albeit, there arise the need for greater evaluation into the long-term studies looking into effective ways to manage on the issues of increased bleeding to ensure the benefit of increased rate of graft patency is maintained (Mauri et al., 2014). The review has shown increased risks of bleeding with high rate of re-operation associated with clopidogrel therapy pre-operative. Nevertheless, the same drug appears very beneficial pre- and post-operative with respect to reducing ischemic events and improving graft patency coupled with reducing thrombotic effects respectively. In context, there is need for effective balancing of the risks pertaining to peri-operative procedure, as well as post operative stage and full recovery (Gurbuz et al., 2005). Conclusion In conclusion, this study looked into the utilization of dual therapy in respect to bypass surgery in cardiovascular procedures. The study aimed at evaluating whether anti-platelet therapy administered pre-operatively for coronary artery diseases preoperatively result to bleeding or enhance patients bleeding during bypass surgery. The effective utilization of aspirin and clopidogrel is paramount pre-operative for patients undergoing anti-platelet therapy to enhance graft patency and reduce ischemic complications occurrence, while at the same time ensuring bleeding problem management (Kim et al., 2009; Gao, et al., 2010; Calafiore, et al., 2010; Simon et al., 2013). From analysis, it is evident that dual utilization of plavix and aspirin results to more benefits to the patient in respect graft patency and reduction in ischemic complications. Thus, it necessary to discontinue clopidogrel and continue with aspirin prior to cardiac surgery and re-introduce it immediately after surgery to enhance the benefit of post-operative grafts patency. Further, combined therapy of the two drugs results to increased bleeding which may prompt re-operation, however, effective intervention measures are paramount to counter bleeding, for example increased blood transfusion. Thus effective transfusion for blood and blood product peri-operative ought to be considered as a critical intervention measure. The review of the various studies has indicated increased risk of hemorrhage with usage of the anti-platelets. Amid the increase rate of bleeding associated with the use of the anti-platelets therapy; with respect to artery bypass surgery, there is also the need for long-term benefit associated with promoting graft patency. The utilization of the combined therapy of aspirin and clopidogrel pre-operative with the option of increase blood and blood products transfusion enhances long term benefits of graft patency coupled with reduced ischemic events. This brings the need to recommend further studies looking into how to effectively reduce bleeding during cardiac surgery with continuation of dual therapy of aspirin and clopidoglel. The critical aspect behind the approach involves ensuring that the long-term post-operative benefits are achieved with the continuation of the combined therapy pre- and post-operatively. Further, management of increased bleeding among high risk patients can be addressed with respect to increased transfusion. 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