Influence of Aspirin on Post Tooth Extraction Bleeding

Influence of acetylsalicylic acid on Post Tooth Extraction BleedingABSTRACTAim The aim of the take up was to evaluate the influence of acetylsalicylic acid on post rootage bleed in a clinical setup.Materials and Method 200 Patients aged between 50 to 65 years, who were indicated for alveolar inception was selected from exposepatient department of Oral and Maxillofacial Surgery. All the patients were every which way divided in aspirin continuing group ( base A) and aspirin discontinuing group (Group B). After checking all the indispensable signs blood lines were carried out. Bleeding clock judgment of conviction and clotting succession was recorded for evaluation by Chi Square Test.Results Chi Square test asserted that the bleeding time cast up (3.80.75) in Group B patients who continued with the anti blood platelet therapy while it come downd in Group A patients who throw in the toweld aspirin. Similarly clotting time increased in group B patient and decreased in Gro up A patient. But in both the groups, bleeding and clotting time remained in spite of appearance normal coifs.Conclusion Assessing most of the dental and medical literature it can be concluded that there is absolutely no need to discontinue anti platelet therapy for any ambulant dental procedure and even if practitioner wishes to discontinue, it should not be more than 3 eld. This is also state in the guidelines of American Heart sleeper.Keywords Anti platelet drugs, Aspirin, Bleeding time, Tooth extraction.INTRODUCTIONMedical practitioners commonly advice their patients who are on antiplatelet therapy to either pulley-block or alter their medications anterior to operative procedures due to fear of excessive and uncontrolled bleeding. This is a proven fact that aspirin causes increased run a risk of intraoperative as well as postoperative bleeding and also increased risk of thromboembolic events such as myocardial infraction and cerebrovascular accidents if the drug is conti nued1. Thrombotic and thromboembolic occlusions of blood vessels are the main cause of ischaemic events in heart, lungs and brain2. In case of blood vessel injury hemostatic mechanism is responsible for stopping the extravasation. Mainly hemostatic mechanism in characterized by twain consecutive phases primary and secondary. Primary mechanism arrests early bleeding as a result of platelet plug formation3. Secondary hemostasis phase is talk terms by complex cascade of clotting factors which helps in formation of fibrin clot4. In novel years lot of research and progress have been made in the field of antiplatelet agents and anticoagulants. These drugs have been utilized for the management of arterial thrombosis also2. Even though a number of antiplatelet and anticoagulant agents have been developed, aspirin and warfarin remains the exemplar drug of choice5.Development of aspirin dates back to 1897 and is considered as one of the safest and cheapest drug worldwide. A general prac titioner Lawrence Craven prescribed low dose aspirin (Baby Aspirin) to his 400 patients and none of them developed myocardial infraction6. This was probably the first time in medical history where aspirin was used to prevent myocardial infarction. Since past it has become the drug of choice for cardiologists.The antithrombotic effect of aspirin is mediated by irreversible inhibition of cyclooxygenase activity in platelets. Phospholipase-A2 acts on the cell membrane to release arachidonic acid on activation. Cyclooxygenase acts on arachidonic acid to produce thromboxane A2. Thromboxane A2 is a potent platelet stimulant leading to degranulation of platelet and platelet aggregation. Aspirin inhibits cyclooxygenase enzyme and decreases the level of platelet stimulant thromboxane A2,5 thus increasing the bleeding time. This is the important reason for a medical practitioner to stop aspirin 3 to 7 days prior(prenominal) to any invasive surgery.The purpose of this study was to investiga te the influence of aspirin on post extraction bleeding.MATERIALS AND METHODThis study was conducted at the outpatient Department of Oral and Maxillofacial Surgery. Patients who were on aspirin therapy, aged between 50 to 65 years and who had to undergo tooth extraction were selected for the study. Patients on warfarin, non-steroidal anti-inflammatory drugs, heparin, steroids or suffering from blood disorders and diabetes were excluded from the study. Informed consent was obtained from the patients with the ethical committee clearance.Two hundred patients including both males and females whose teeth were indicated for extraction were included in the study. Patients were randomly divided into Group A and Group B of 100 patients each. Group A patients continued to receive aspirin preoperatively while Group B patients were asked to stop aspirin 7 days prior to extraction.Pre operatively all the vital signs (Blood Pressure and Pulse) were measured. Bleeding time (White and Lee techniqu e) and clotting time (Ivys technique) was calculated. Extractions were carried out only if the higher up parameters were within normal range. After tooth was extracted presence or absence of bleeding and bleeding time was recorded. Analgesics and antibiotics were prescribed as needed for pain sensation and infection control.Chi hearty test was used to evaluate the relative frequencies of patients in both groups. Differences of parametric variables were tested with analysis of variance.RESULTSAfter applying Chi square test, mean bleeding time was calculated as 2.10.52 minutes in the patients who discontinued baby aspirin (Group B) 7 days prior to extraction. Bleeding time of Group A patients who continued aspirin through the entire study was found to be 3.80.75 minutes. This difference was statistically significant (p=0.002) Table 1. Although there is significant increase in the bleeding time of Group A patients it should be noted that bleeding time of both the groups was within t he normal limits. Clotting time of Group B patients was 3.80.75 and Group A was 4.70.74 which was also within the normal limits (Normal range according to Ivys Method 3 to 5 minutes).DISCUSSIONhistorically aspirin was used as an anti-inflammatory, analgesic and antipyretic drug for a short period of disease activity. Lawrence Craven in 1950 reported for the first time its long term use to prevent myocardial infarction6. He advocated a lower dose for antiplatelet action. Antiplatelet activity of aspirin occurs at doses ranging as low as 40 mg/day7 to 3208 mg daily. Doses above 320 mg/day decrease the effectiveness of aspirin as antiplatelet agent due to inhibition of prostacyclin production9. However recent clinical trial indicates that 160 mg/day is optimal for antiplatelet action10. In emergencies where urgent antithrombotic action is required a loading dose of 300 mg is advocated9. Usually in United States daily dose of 81 mg, 160 mg or 325 mg are prescribed while in europium and other countries daily dose of 75 mg, 150mg or 300 mg are prescribed10.Risk of continuing aspirin therapy prior to surgery is that, with the alteration of platelet function longer time period is required to stop the bleeding from a surgical site. This is attributed to the alteration in primary hemostatic mechanism. Burger et al stated that, in patients on aspirin, the average risk of bleeding increases 1.5 folds. At the same time there is a risk in stopping the aspirin prior to surgery leading to a potential risk of rebound of thromboembolic vascular events. On stopping aspirin thromboxane A2 activity increases to a greater extent with decrease in fibrinolytic activity11. Ferrari et al showed the existence of biological platelet rebound phenomenon on interruption of aspirin therapy. This could create a prothrombotic state which may lead to opprobrious thromboembolic events. Approximately 20% of these episodes are fatal and another 40% can lead to permanent disability12.Practitioner s who advocate the stoppage of aspirin have been debating among themselves regarding the time limit to stop aspirin. Literature wise the effect of aspirin on platelets is irreversible. The effect lasts for 7 to 10 days which is the life span of platelets13, 14. Therefore since early days it was recommended to stop aspirin 7 days prior to surgical procedure15-19. Sonksen et al in their study comprising of 52 healthy individuals showed that withdrawal of aspirin for more than 5 days was not recommended20. Wahl et al advocated that aspirin should be discontinued for 3 days only as after 3 days of interruption of aspirin, suitable number of newer platelets would be present in circulation for hemostasis21, 22.Now again the debate arises whether to stop aspirin therapy or not? Fear for uncontrolled bleeding encourages the practitioners to discontinue the aspirin therapy. Few studies have shown that there is always an increased risk of bleeding in patients continuing aspirin23, 24. Hence few studies recommended stopping of aspirin therapy prior to surgical procedure17, 19, 25. However if the aspirin therapy is discontinued, there is increased risk of thromboembolic events which can be fatal but none of these have been reported in dental literature. Fijnheer et al in his article mentioned that there is scarcity of literature regarding dental surgeries involving patients on aspirin medication26. Little et al recommended that unless bleeding time is increased above 20 minutes aspirin affected platelets would not cause significant bleeding complication22. Similar claims were made by Sonksen et al and Gaspar et al20, 27.Canigral et al conducted a research involving surgical extraction in patients on antithrombotic therapy. In 92% cases bleeding stopped within 10 minutes with pressure alone. This result was in abidance with the present study4. Gaspar et al advocated that ambulatory oral surgical procedures can be performed in patients without discontinuing the use of aspi rin27. A recent recommendation from American Heart Association and American College of Cardiology is that, either continuing aspirin or clopidogrel therapy for minor oral surgical procedures in patients with coronary artery stents or delaying treatment until prescribed sustenance will be complicated.The present study demonstrated that there was significant increase in the bleeding time in both the groups but in no case it was difficult to stop the bleeding. Although bleeding time increased in the Group A patients but it still remained within the normal range, unheeding of whether patients continued or discontinued their aspirin therapy28, 29, 30. This result was similar to the study done by Canigral et al4. Valerin et al conducted a study with 17 patients randomized to aspirin and 19 to placebo and found no differences in bleeding outcomes for patients on aspirin. This finding suggested that there was no need to discontinue aspirin prior to any ambulatory oral surgical procedures3 1.Adchariyapetch compared the postoperative bleeding on subjects who stopped or continued taking the aspirin for seven days prior to extraction. The mean bleeding time in both the groups was in normal range. After the procedure there was no difficulty in achieving hemostasis. Therefore they concluded that surgical extraction did not require discontinuation of antiplatelet therapy32. Matocha in his study concluded that risk of bleeding after dental extraction is very minimal in the patients with aspirin therapy and did not exceed 0.2 to 2.3%33.Murphy et al concluded with a survey that 86% of the dental practitioners who advised the patient to stop antiplatelet drugs prior to dental extraction did so with the consultation of the patients physician and found that the protocol followed by the physicians and dentists was not based on the current recommendations and guidelines34.Napenas et al concluded that the risk of stopping antiplatelet therapy and predisposing the patient to thromboe mbolic events overweighed the minimal risk of bleeding from dental procedures. Similar results were found in the study done by Nielsen et al35. Wahl in a research study reported that in 950 patients receiving anticoagulation therapy, only 12 required (