The Efficacy of Tranexamic Acid Versus Epsilon Amino Caproic Acid in Decreasing Blood Loss in Patients Undergoing Mitral Valve Replacement Surgery

Transcription

1 Journal of Anesthesiology 2017; 5(2): htt:// doi: /j.ja ISSN: (Print); ISSN: (Online) The Efficacy of Tranexamic Acid Versus Esilon Amino Caroic Acid in Decreasing Blood Loss in Patients Undergoing Mitral Valve Relacement Surgery Sanjeev Singh 1, 2, 3, *, Anbarasu Annamalai 2 1 Deartment of Anaesthesia and Intensive Care, School of Medical Sciences, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana 2 Deartment of Cardiac Anaesthesia, NHIMS, Bangalore, Karnataka, India 3 Deartment of Cardiac Anaesthesia, SAMSRI, Lucknow, India address: drsanjeev73@rediffmail.com (S. Singh) * Corresonding author To cite this article: Sanjeev Singh, Anbarasu Annamalai. The Efficacy of Tranexamic Acid Versus Esilon Amino Caroic Acid in Decreasing Blood Loss in Patients Undergoing Mitral Valve Relacement Surgery. Journal of Anesthesiology. Vol. 5, No. 2, 2017, doi: /j.ja Received: January 29, 2017; Acceted: February 9, 2017; Published: Aril 13, 2017 Abstract: Oen heart surgeries under cardioulmonary byass are associated with excessive erioerative bleeding that often requires re-exloration. Antifibrinolytics like esilon aminocaroic acid and tranexamic acid are widely used to control bleeding. There is aucity of literature on studies to reduce blood loss and blood transfusion following mitral valve relacement surgeries. The aim of this study was to comare incidence of re-exloration, blood loss and blood transfusion following mitral valve relacement surgeries in atients who were administered either tranexamic acid or esilon amino caroic acid. However their efficacy has not been studied in mitral valve relacement surgeries. This is a rosective, randomized, double blind study erformed among sixty atients of either sex in the age grou of 18 to 60 years scheduled for mitral valve relacement surgeries. They were randomly allocated into two grous, Grou 1 (TA n=3o) tranexeamic acid 20 mg/kg body weight diluted in 20ml syringe over 20 min as bolus at time of induction of anaesthesia, infusion of 2mg/kg/hr started continued throughout surgery and continued till 6 hour ost oeratively in recovery room. Grou 2 (EACA n=30) esilon amino caroic acid 100 mg/kg body wt bolus diluted to 20 ml syringe over 20 min as bolus at time of induction of anaesthesia, infusion 20mg/kg/hr started continued throughout surgery and continued till 6 hour ost oeratively in recovery room. After admission to intensive care unit total blood loss, transfusion requirements during the first 24 hours and other comlications were recorded. In our study we found that mean ost oerative blood loss in tranexamic acid grou (ml) which is lower than esilon amino caroic acid grou (ml) that is statistically significant. 16 out of 30 atients in TA grou i.e. 53.3% atients received transfusion, where as in EACA grou 21 out of 30 atients i.e. 70% atients received transfusion. The total transfusion requirements, total donor unit exosure and financial cost of blood comonents are less in the tranexamic acid grou. Prohylactic tranexamic acid effectively reduces erioerative blood loss in mitral valve relacement surgery. Keywords: Esilon Amino Caroic Acid, Mitral Valve Relacement, Post Oerative Bleeding, Tranexemic Acid 1. Introduction Cardioulmonary byass (CPB) is a double-edged sword. Without it, corrective cardiac surgery would not be ossible in the majority of children with congenital heart disease. In 1953, John Gibbon erformed the first successful oen-heart oeration using a heart-lung machine in human atient. Blood requirements er cardiac case in the early 1950's were 20 to 30 units [1]. Desite continuous advances imroving the safety of cardiac surgery, excessive bleeding requiring transfusion of blood comonents after CPB is still one of the main causes of ostoerative morbidity [2]. The nonendothelial surfaces of the CPB circuit cause contact activation of the coagulation

2 12 Sanjeev Singh and Anbarasu Annamalai: The Efficacy of Tranexamic Acid Versus Esilon Amino Caroic Acid in Decreasing Blood Loss in Patients Undergoing Mitral Valve Relacement Surgery cascades and of latelets, desite the use of hearin. Thus, CPB is associated with several alterations in the haemostatic mechanisms including increased fibrinolysis, decreased latelet numbers and function, dilution of clotting factors, and the residual effects of hearin or excess rotamine. Increased fibrinolytic activity and latelet dysfunction have been identified as imortant factors of ostoerative bleeding [3]. In cardiac surgery ostoerative bleeding is associated with an increased incidence of surgical re-exloration to identify the source of bleeding. Increased use of blood causes significant morbidities such as renal failure, sesis, arrhythmias, rolonged requirement for mechanical ventilatory suort, longer hosital stay and increased mortality [4]. Public arehension of transfusion related communicable diseases articularly AIDS, modulation of the immune resonse, and increased risk of ostoerative infection, the roblems of occasional shortages of donor blood and increasing costs [1], has refocus the attention of cardiac surgeons on the imortance of haemostasis to minimize the need for, and therefore the risk of blood transfusion. These risks increase roortionately to the number of donors to which the reciient is exosed. The use of drugs to reduce bleeding in the ost-oerative eriod of CPB assisted heart surgery has been studied since the reort by Mammem et al. with arotinin in 1968 [5]. From 1980, there has been growing interest in methods to minimize the exosure to blood and its derivatives in the eri-oerative eriod, as it was discovered that HIV, heatitis etc could be transmitted by transfusions [4]. At resent three antifibrinolytic agents of which two synthetic (esilon aminocaroic acid, tranexamic acid) and one natural (arotinin) that are available for clinical use. The most thoroughly evaluated antifibrinolytic agent is arotinin. Its effectiveness in reducing ostoerative haemorrhage has been established in more than 40 randomized clinical trials and 2 meta-analyses. However, arotinin is exensive. In addition, there are concerns about otential thrombosis related side effects and allergic reactions with antifibrinolytic agents. For these reasons, rohylactic use of arotinin is often limited to atients at high risk for bleeding (eg, reoerations) or those for whom transfusions are not accetable because of religious beliefs (eg, Jehovah's Witnesses). The FDA required new labeling for arotinin, focusing on indications for use, added a warning about renal dysfunction, revised a warning about anahylactic reactions, and added a contraindication. On October 19, 2007, a communication to the FDA from the Data Safety Monitoring Board of a Canadian randomized study evaluating the safety of antifibrinolytic theraies stated that the trial was being halted because of a higher mortality trend in the arotinin arm. Reacting to this negative finding, the FDA announced the susension of arotinin marketing in 2007 [6]. Esilon aminocaroic acid (EACA) and tranexamic acid (TA) are antifibrinolytic agents that are inexensive and that do not have the increased risk of anahylaxis of arotinin uon re-exosure. Treatment with either EACA/ TA rior to CPB has been shown to reduce blood loss in erioerative eriod following oen heart surgery [1-4]. The use of tranexamic acid in cardiac oerations has been reorted in more randomized trials than esilon aminocaroic acid. A lacebo control grou was not used for this study since the efficacy of the drugs has been established in the literature. So it would have been unethical to conduct lacebo control study. Thus tranexamic acid was chosen as the synthetic antifibrinolytic to comare against esilon aminocaroic acid. The urose of the resent study was therefore, to comare the efficacy of tranexamic acid vs esilon aminocaroic acid on ostoerative bleeding and transfusion requirements following mitral valve relacement surgery. 2. Material and Methods This study was undertaken after an institutional aroval by the Committee on Human Research Publications and Ethics was obtained. The study was conducted from November 2013 to May Informed consent was obtained from 60 atients. The study oulation consisted of American Society of Anaesthesiologists (ASA) hysical status III; male and female adults between the ages of years scheduled for mitral valve relacement surgery under general anaesthesia Study Design This study was a rosective, randomised and doubleblinded clinical comarison. The Samle size for the study was 60 generated using a samle size calculator. The study Particiants were randomly divided into two grous by a comuter generated randomization table. Grou 1 (TA n=3o) tranexeamic acid 20 mg/kg body wt diluted to 20 ml of NS over 20 min as bolus at time of induction of anesthesia, and infusion of 2mg/kg/hr started continued throughout surgery till 6 hour ost oeratively in recovery room. Grou 2 (EACA n=30) esilon amino caroic acid 100 mg/kg body wt bolus diluted to 20 ml of NS over 20 min as bolus at time of induction of anesthesia, & infusion 20mg/kg/hr started continued throughout surgery till 6 hour ost oeratively in recovery room. Both the drugs were coded to enhance blinding Inclusion Criteria Inclusion criteria for the study were ASA class III; age range 18 65, either sex, osted for elective mitral valve relacement surgery, reoerative hemoglobin >10 gm %, haematocrit >30%, normal coagulation rofile including PT and INR Exclusion Criteria Exclusion criteria for the study included atients who were morbidly obese; Heart rate <50 beats er minute (bm), basal SBP<100 mmhg, bleeding diathesis, allergic reaction to anti fibrinolytic drugs, deranged coagulation rofile PT<75% or INR>2, thrombosis, urinary tract bleeding, Pre oerative renal failure (serum creatinine >2), Pregnancy, Patient on anti latelet treatment within 7 days of surgery, Redo surgery, emergency oeration and atients refusal.

3 Journal of Anesthesiology 2017; 5(2): Pre-Surgical Protocol The day rior to surgery all atients underwent a reanesthetic evaluation with secial consideration to elicit any new change, revious anaesthetic history and drug sensitivity. Information collected included weight, nutritional status, airway assessment by the Mallamatti scoring system; a detailed examination of the resiratory; cardiovascular and central nervous system. A reoerative routine investigations such as haemoglobin, haematocrit, total lymhocyte count, differential lymhocyte count, serum electrolytes, blood grou/rh tying, blood urea nitrogen, serum creatinine, fasting blood sugar, chest radiograhy, Echo and electro-cardiogram in all atients. Patients were advised to fast the night rior to surgery Surgical Protocol After atient identification a short reoerative history was taken; clinical examination and routine investigations were rechecked in all atients. Study objective and rocedure were exlained to the articiants and a written informed consent was obtained from each articiant. Baseline vitals like heart rate, rhythm, non invasive blood ressure monitoring (NIBP), SO 2, resiratory rate were monitored before induction. A eriheral line intra venous (IV) line was established with 20G IV cannula and Ringer Lactate infusion was started. Premedication with IV Fentanyl 3 µg/kg and Midazolam 0.05mg/kg was administered. Central venous, radial / femoral arteial lines were established under local anaesthesia. Invasive blood ressure as well CVP was monitored. Study drugs given as above mentioned as er rotocol by anaesthetist who is blinded for study. Patient was induced with inj. Thioental 5-7mg/kg. Neuromuscular blocked was achieved and maintained with vecuronium 0.15mg/kg. Intubation was done with the aroriate sized cuffed endotracheal tube. After inflating the cuff and securing the tube, controlled mechanical ventilation was started and anaesthesia was maintained on O 2 with inhalational anaesthetic agent 0.6% -1.2% Isoflurane on semi closed circle system with CO 2 absorber and flow rate of 3 lit/min (Datex ohmeda). Fentanyl, midazolam, vecuronium were administered as er needs. Hearin was given at a dose of 300 U/kg and sulemented as necessary to maintain ACT>400 sec while on Cardio Pulmonary Byass. Pum rime consisted of 1200ml balanced electrolyte solution and 500ml of tetra starch containing 25meq of sodium bicarbonate and 5000 units of hearin mannitol 100 ml and, lasix 1 mg/kg. CPB was maintained with roller um utilizing a membrane oxygenator. All Patients underwent standard nonulsatile normothermic or mildly hyothermic (28 C to 32 C) Cardio Pulmonary Byass. Myocardial rotection was induced with ml/ kg of cold high otassium cardiolegia (16 mmol otassium in 20 ml legiocard solution) through the aortic root after aortic occlusion. After mitral valve relacement, closure of left atrium done & rest time atient is gradually weaned from byass. Inotroes, vasoressors, vasodialtors etc were administered as er needs. Hearin was neutralized with rotamine 1.5 mg/100 IU hearin administered. Blood samles was collected for Hb, ABG and electrolytes at the following time oints after induction, immediately after hearin administration, following neutralization with rotamine, ostoeratively every hourly till 6 hours, at 9, 12, 18, and 24 hour. Activated clotting time (ACT) was erformed at baseline, after hearine administration, after rotamine titration, ost oeratively, if bleeding is >200ml/hour. Patient monitored as er standard hosital rotocol for cardiac surgery throughout erioerative course. After skin closure atient shifted to recovery room, there drain bottles attached to slow suction. Patients were mechanically ventilalated for 3-4 hour. If atient is without any comlication and stable then weaned off from the mechanical ventilation Parameters and Statistical Analysis Summary statistics of atient demograhic for both the grous were reorted as means ± Standard deviation (SD). Data for continuous arameters was collected and comared between Grou I and Grou II. Statistical analysis was done by unaired t-test whilst non normalized data were comared using Mann Whitney test. value less than 0.05 was considered as statistical significant. Data was analyzed by statistical software SPSS Results A comarison of the demograhic rofile of the study grous are as shown in Table 1. No significant difference was observed in the mean age for grou 1TA atients (29.3±10.35 years) when comared to those in grou 2 EACA (32.4±11.8 years) (=0.284). The male to female ratio of grou 1TA was 1:1.5 whereas that of grou 2 EACA was 1:2.6 (=0.34). The average weight was 42.9±12.5 kg and 43.5±6.89 kg in grous 1 and 2 resectively (=0.8161). The average height in grou I was 153±12.70 cm and grou II was ±11.05 cm (=0.5324). The average body mass index was and in grou 1 and 2 resectively (=0.625). Table 1. Comarison of TA verses EACA (reoerative demograhic rofile). Parameter GROUP 1 TA (n=30) GROUP 2 EACA (n=30) P Age (yrs) 29.3± ± Sex ratio M/F 1:1.5 1: Weight (kg) 42.9± ± Height (cms) 153± ± Body mass index Preoerative arameter

4 14 Sanjeev Singh and Anbarasu Annamalai: The Efficacy of Tranexamic Acid Versus Esilon Amino Caroic Acid in Decreasing Blood Loss in Patients Undergoing Mitral Valve Relacement Surgery Table 2. Shows reoerative investigations of atients in both the grous. Parameter Grou 1 (TA n=30) Grou 2 (EACA n=30) Hb % 11.6± ± INR 1.14± ± KFT Blood urea 25.03± ± KFT Serum creatinine 1.07± ± The table 2 shows reoerative Hb%, INR and kidney function test. There were no statistically significant reoerative intergrou differences with resect to Hb%, INR and kidney function test (>0.05). Intra oerative Parameter Parameter Table 3. Comarison of TA verses EACA (Intra oerative coagulation states and duration of cardioulmonary byass). Grou 1 (TA n=30) Grou 2 (EACA n=30) ACT Baseline (sec) ± ± ACT ost Hearin (sec) ± ± ACT after rotamin (sec) ± ± Duration of byass (mins) ± ± Intra oerative arameters like coagulation states and duration of cardioulmonary byass are resented in table 3. It shows that activated clotting time ACT (baseline, ost hearin and after rotamine titration) not significant in both the grous (>0.05). Mean duration of byass in TA grou ± mins which does not vary significantly from that in EACA grou ± mins (=0.902). Post oerative blood loss at 24 hours Parameter Table 4. Comarison of TA verses EACA (mean ostoerative blood loss at 24 hours). Grou 1 TA (n=30) GROUP 2 EACA (grou) Total Chest Drain After 24 Hour (ml) ± ± P Table 4 shows mean ostoerative blood loss at 24 hours (measured in terms of amount of blood collected in chest drain) in both grous. Patients in TA grou significantly lower ostoerative blood loss at 24 hour as comared to atients in EACA grou. Mean ostoerative blood loss at 24 hour in grou 1 (TA) ± ml which is much lower than ost oerative blood loss at 24 hour in grou 2 (EACA) 489 ± ml (=0.0001) which is statically significant (=0.0001). Post oerative blood loss Table 5. Comarison of TA verses EACA (mean ostoerative blood loss in ml). BLOOD LOSS (ml) Grou 1 TA Grou 2 EACA 1 hr 63.66± ± hr 53.33± ± hr 42.66± ± hr 35.33± ± hr 29.00± ± hr 39.33± ± hr 39.00± ± hr 38.66± ± hr 36.33± ± hr 38.66± ± Total ± ± In table 5 analysis of blood loss at timely interval as er study rotocol. The blood loss is recorded at hourly interval u to first 6 hour thereafter at 9, 12, 18 and 24 hours. Mean blood loss at secified interval in each grou is shown in table no 5. The mean blood loss was higher in EACA grou ostoeratively as comared to TA grou u to first 6 hrs. Statistically this difference is highly significant. After 6 hours though mean blood loss is higher in EACA grou as comared to TA but the difference is not statistically significant. These trends are lotted in grah 1.

5 Journal of Anesthesiology 2017; 5(2): Figure 1. Postoerative blood loss trends in both grous. The number of units of whole blood or blood comonent transfused Table 6. Comarison of TA verses EACA (units of blood, blood comonents transfused/all atients). Total transfusion (in Units) Grou 1 (TA n=30) Grou 2 (EACA n=30) (Mann Whitney test) Median (interercentile range 25 th -75 th ) Median (interercentile range 25 th -75 th ) Blood 0.45 ± ± FFP 0.48 ± ± Platelet 0.35 ± ± Table 6 demonstrates the comarison of number of units of whole blood or blood comonent transfused/all atients between two grous. There is a significant decrease in number of units of whole blood transfusion requirement in TA grou as comared to EACA grou as shown in table above. TA grou received on an average 0.45±0.62 unit/er atient as comared to EACA grou 0.86±0.87 units er atient. The number of units of FFP and latelet required er atient did not vary significantly among two grous Number of atients requiring transfusion of blood/blood roducts Table 7. Shows number of atients requiring transfusion of blood/blood roducts. Parameter Number of atients receiving transfusion Grou 1 TA (n=30) Grou 2 EACA (n=30) 16 (53.3%) 21 (70%) From table 7 it is seen that 16 out of 30 atients in TA grou i.e. 53.3% atients received transfusion where as in EACA grou 21 out of 30 atients i.e. 70% atients received transfusion. Hemoglobin and INR on second day Table 8. Focuses on variation between two grous in regard to Hb% on second day and INR. Parameter on Grou 1 (TA n=30) Grou 2 (EACA n=30) P day 2 (at 24 hrs) Hb % 10.74± ± INR 1.41± ± Table 8 it is reveal that mean Hb% of atients in TA grou (10.74±1.23) was slightly better as comared to mean Hb% of atients in EACA grou (9.95±1.26) on second day. The difference is statistically significant ( < 0.05). From above table it is seen that INR on day 2 in grou 1 TA is 1.41±0.26 and in grou 2 is 1.33 ±0.28. The difference is not statistically significant. Re-exloration: None of the atient in either grou has been re exlored. Adverse outcome: No comlications like kidney failure, stroke, AMI were observed in either grou. Only 1 atient in EACA grou had convulsions. Pulse rate Pulse rate (er min) Table 9. Comarison of TA verses EACA (ulse rate). TA grou EACA grou Baseline 89.50± ± Prebyass 89.26± ± Postbyass 83.93± ± hr ± ± hr 99.20± ± hr 84.86± ± hr 87.03± ± hr 82.13± ± hr 80.10± ± hr 82.66± ± hr 83.66± ± hr 79.46± ± hr 77.26± ± The ulse rate is recorded at hourly interval u to first 6 hour thereafter at 9, 12, 18 and 24 hours. Mean ulse rate at secified interval in each grou is shown in table no 10. Pulse rate did not vary significantly between two grous showing hemodynamic stability. Systolic blood ressure

6 16 Sanjeev Singh and Anbarasu Annamalai: The Efficacy of Tranexamic Acid Versus Esilon Amino Caroic Acid in Decreasing Blood Loss in Patients Undergoing Mitral Valve Relacement Surgery Table 10. Comarison of TA verses EACA (systolic blood ressure). TA grou EACA grou Baseline ± ± Prebyass ± ± Postbyass ± ± hr ± ± hr ± ± hr ± ± hr ± ± hr ± ± hr ± ± hr ± ± hr ± ± hr ± ± hr ± ± The systolic blood ressure is recorded at hourly interval u to first 6 hour thereafter at 9, 12, 18 and 24 hours. Mean systolic blood ressure at secified interval in each grou is shown in table no 11. Systolic blood ressure did not vary significantly between two grous showing hemodynamic stability. Diastolic blood ressure Table 11. Comarison of TA verses EACA (diastolic blood ressure). Diastolic blood ressure (mm of Hg) TA grou EACA grou Baseline 74.40± ± Prebyass 67.00± ± Postbyass 63.40± ± hr 65.26± ± hr 66.46± ± hr 65.40± ± hr 66.06± ± hr 74.56± ± hr 66.23± ± hr 64.00± ± hr 66.86± ± hr 66.43± ± hr 66.93± ± The diastolic blood ressure is recorded at hourly interval u to first 6 hour thereafter at 9, 12, 18 and 24 hours. Mean diastolic blood ressure at secified interval in each grou is shown in table no 12. Mean diastolic blood ressure did not vary significantly between two grous showing hemodynamic stability. Central venous ressure Table 12. Comarison of TA verses EACA (central venous ressure). CVP TA grou EACA grou Baseline 6.06± ± Prebyass 6.36± ± Postbyass 6.46± ± hr 4.90± ± hr 4.70± ± hr 5.63± ± CVP TA grou EACA grou 4 hr 5.46± ± hr 6.56± ± hr 6.50± ± hr 6.83± ± hr 6.23± ± hr 6.60± ± hr 6.26± ± The central venous ressure is recorded at hourly interval u to first 6 hour thereafter at 9, 12, 18 and 24 hours. Mean central venous ressure at secified interval in each grou is shown in table no 13. Mean central venous ressure did not vary significantly between two grous. Mean central venous ressure was slightly lower in early ostoerative eriod. Hemoglobin % Table 13. Comarison of TA verses EACA (Hb %). Hb % TA grou EACA grou Baseline 11.66± ± Prebyass 11.16± ± Postbyass 10.80± ± hr 9.45± ± hr 8.73± ± hr 9.10± ± hr 9.46± ± hr 9.45± ± hr 9.83± ± hr 9.90± ± hr 9.87± ± hr 9.74± ± hr 10.63± ± The Hb% is recorded at hourly interval u to first 6 hour thereafter at 9, 12, 18 and 24 hours. Mean Hb% at secified interval in each grou is shown in table no 14. Mean Hb% was slightly higher in TA grou as comared to EACA grou. The difference was not statistically significant u to 18 hours. But the difference became statistically significant at 24 hours. Urine outut Urine outut (ml) Table 14. Comarison of TA verses EACA (urine outut). TA grou EACA grou Baseline 71± ± Prebyass 107± ± Onbyass 151± ± Postbyass ± ± hr ± ± hr ± ± hr 98.66± ± hr ± ± hr ± ± hr ± ± hr ± ± hr ± ± hr 621± ± hr ± ± Urine outut was recorded at hourly interval u to first 6

7 Journal of Anesthesiology 2017; 5(2): hour thereafter at 9, 12, 18 and 24 hours. Mean urine outut at secified interval in each grou is shown in table no 12. Mean urine outut did not vary significantly between two grous showing that both grous were comarable in terms of urine outut. Platelet count Platelet count (in thousands) Table 15. Comarison of TA verses EACA (latelet count). TA grou EACA grou Baseline ± ± Prebyass ± ± Postbyass 210± ± hr ± ± hr ± ± hr ± ± hr ± ± hr ± hr ± ± hr ± ± hr ± ± hr ± ± hr ± ± Platelet count was recorded at hourly interval u to first 6 hour thereafter at 9, 12, 18 and 24 hours. Mean latelet count at secified interval in each grou is shown in table no 12. Mean latelet count did not vary significantly between two grous showing that both grous were comarable in terms of latelet count. 4. Discussion One of the common roblems encountered in cardiac surgery and extracororeal circulation is excessive bleeding. This bleeding contributes to both morbidity and mortality comlicate ostoerative care, resulting in transfusion of blood and blood roducts that are exensive and also carries the risk of infection to the reciient. Because both bleeding itself and the transfusions administered to comensate for blood loss have an untoward imact on outcomes, there is strong motivation to decrease the occurrence of bleeding associated with cardiac surgical rocedures in the first lace. The armamentarium to control bleeding includes careful surgical dissection, meticulous haemostasis and harmacological management with new generation antifibrinolytic agents. From nanotechnology, there is only one ste to nanomedicine, which may be defined as the monitoring, reair, construction, and control of human biological systems at the molecular level, using engineered nanodevices and nanostructures [7]. Since Platelet dysfunction and fibrinolysis can contribute to bleeding after oen heart surgery, the administration of antifibrinolytic agents aears to be a suitable aroach to reducing ostoerative bleeding in atient with oen heart surgery. Inexensive antifibrinolytic agents like Esilon amino caroic acid and tranexamic acid have been shown to reduce blood loss associated with many surgeries. Esilon amino caroic acid and tranexamic acid rimarily exert their antifibrinolytic effect by forming a reversible comlex with lasminogen, which inhibits its conversion to lasmin and it s binding to fibrin. Therefore, it is not surrising that D- dimers were reduced in atients exosed to esilon amino caroic acid and tranexamic acid, esecially since the concentration of D-dimers is a sensitive measure of fibrinolysis. Since lasmin activates latelets, antifibrinolytic may also affect hemostasis by reventing lasmin induced latelet activation [8]. As efficacy of antifibrinolytic agents to decrease the ostoerative bleeding has been well documented in literature so it would have been unethical to conduct lacebo control trial. Therefore we decided to comare the efficacy of lysine analogue EACA and tranexamic acid in reducing ostoerative blood loss and transfusion requirement following mitral valve relacement surgery. As estimates of intraoerative blood loss are too inaccurate for study urose, so we collected and measured total chest tube drainage at secified interval u to 24 hrs as er study rotocol, starting from the time of chest closure. Harrow et al in their dose resonse study of tranexamic acid found that lowest dose was 10 mg/kg followed by 1 mg/kg/hr. However, the lowest median mediastinal drainage in their study was with a dose 20 mg/kg followed by 2 mg/kg/hr [9] and same was in Shore-Lesserson et al [10]. The same dose of tranexamic acid was chosen for the current study. Dose of EACA is based on Dowd et al study to maintain blood EACA concentrations at or above 260 mg/l [11]. These studies showed the heterogeneity of samle oulation selected for their studies, to avoid this we selected uniform samle oulation i.e. atients undergoing only mitral valve relacement surgery. In our study we decided to administer EACA or tranexamic acid immediately after induction of anaesthesia and rior to skin incision to reduce the total amount of blood in the ostoerative eriod. Prior studies have noted that once significant bleeding had develoed, the usefulness of antifibrinolytic administration were unredictable. This is not unexected, since the breakdown of fibrin results in release of fibrinoetides that interfere with the olymerization of fibrin, hereby functioning as an anticoagulant. The unique feature in this study is that the antifibrinolytics are extended for 6 hour in ost oerative eriod. Due to the fact that hemodynamic instability, chances of ost oerative bleeding and incidence of re exloration are more frequent in first few hours after surgery. The imortant finding of this study is that tranexamic acid significantly reduces ostoerative bleeding when comared to EACA in atients undergoing mitral valve relacement surgery. In our study we found that mean blood loss in 24 hours with tranexamic acid is 416 ± (ml) which is lower than esilon amino caroic acid 489 ± (ml). This difference is statistically significant. The mean blood loss in tranexamic acid was statistically significant lower than EACA in first 6 hours (Table no 4, 5). Henry et al. (2007) in

8 18 Sanjeev Singh and Anbarasu Annamalai: The Efficacy of Tranexamic Acid Versus Esilon Amino Caroic Acid in Decreasing Blood Loss in Patients Undergoing Mitral Valve Relacement Surgery a similar study reorted insignificant difference between tranexamic acid and EACA. They found that there was no statistically significant difference between TA and EACA in the volume of blood lost during the ost-oerative eriod. But the oulation under consideration in this study was not uniform. Pattern of bleeding in CABG, congenital defect reair, redo surgery, and valve relacement surgery is different. Dose regimen used in study was different. We had a uniform samle i.e. atients undergoing mitral valve relacement surgery and we extended duration of drug infusion u to first 6 hour in ost oerative eriod which is much versatile eriod. Our findings are consistent with Pinolsky et al and Casati et al as they found that tranexamic acid and EACA effectively inhibited fibrinolytic activity intraoeratively and throughout the first 24 hours ostoeratively, but again the oulations under consideration in these studies were not uniform. Tranexamic acid was more effective in reducing blood loss ostoeratively in aediatric atients undergoing cardiac surgery. 5. Limitation of Our Study We selected the dose of TA from study of Shore-lesserson to rovide necessary theraeutic concentration and similarly dose of EACA is based on study of Butterwoth et al to rovide constant theraeutic level of 260ng/ml. We could not measure the lasma level of drugs in our study. We could extend this study with increased and decreased doses to comare results. To generalize the result we need to conduct multi centric trial with large samle size. Ideally FFP should be administered according to coagulation rofile and INR. But in our study FFP were transfused as er anesthesiologists /surgeons view or in the resence of massive blood transfusion. 6. Conclusion Tranexamic acid is more efficacious than ε amino caroic acid in regard to decrease ostoerative blood loss and blood roduct requirement. Who were undergoing mitral valve relacement surgery treated with tranexamic acid had 73ml less total blood loss in 24 hours, the total transfusion requirements, total donor unit exosure and financial cost of blood comonents are less in the tranexamic acid grou. Prohylactic tranexamic acid can reduce erioerative blood loss in mitral valve relacement surgery. References [1] Santos ATL, Kalil RAK, Bauemann C, Pereira JB, Nesrall IA. A randomized, double-blind, and lacebo-controlled study with tranexamic acid of bleeding and fibrinolytic activity after rimary coronary artery byass grafting. Brazilian Journal of Medical and Biological Research 2006; 39: [2] Moulton MJ, Creswell LL, Mackey ME. Re-exloration for bleeding is a risk factor for adverse outcomes after cardiac oeration. Journal of Thoracic and Cardiovascular Surgery 1996; 111: [3] Hassan MK, Hasan KA, Salam ABMA, Razzak A, Ferdous S, Maruf MF, Ahmed MU, Haq N, Ahsan NAK. Effect of Tranexamic Acid after Cardiac Surgery in Children. Cardiovascular Journal. 2009; 1 (2): [4] Buck ML. Use of aminocaroic acid in children undergoing Cardiac Surgery and ECMO. Paediatric Pharmacotheray 2006; 12: 1-4. [5] Karski JM, Dowd NP, Joiner R, Carroll J, Peniston C, Bailey K et al. The effect of three different doses of tranexamic acid on blood loss after cardiac surgery with mild systemic hyothermia (32 C). J Cardiothorac Vasc Anesth 1988; 12: [6] Koster A, Faraoni D, Levy JH. Antifibrinolytic Theray for Cardiac Surgery An Udate. The Journal of the American Society of Anesthesiologists. 2015; 123 (1): [7] Singh S, Singh A. Current status of nanomedicine and nanosurgery. Anesth Essays Res 2013; 7: [8] Falanga A, Russo L, Tartari CJ Pathogenesis and Treatment of Thrombohemorrhagic Diathesis in Acute Promyelocytic Leukemia. Mediterr J Hematol Infect Dis. 2011; 3 (1): e [9] Harrow JC, Daniel F, Rier V. Hemostatic effect of Tranexamic acid and Desmoressin During Cardiac Surgery. Circulation 1991; 84: [10] Shore-Lesserson L, Reich DL, Vela-Cantos F, Ammar T, Ergin MA. Tranexamic acid reduces transfusions and mediastinal drainage in reeat cardiac surgery. Anesth Analg Jul; 83 (1): [11] Dowd NP, Karski JM, Cheng DC, Carroll JA, Lin Y, James RL, Butterworth J. Pharmacokinetics of tranexamic acid during cardioulmonary byass. Anesthesiology. 2002; 97 (2):