Transfusion support in Surgery- elective surgery, cardiac surgery, MSBOS, Transfusion trigger, autologous transfusion

AABB indications
Elective surgeries- Maximum surgical blood ordering schedule
Anemia and surgery- including Transfusion Trigger
Surgery and coagulation disorders- including factor replacement
Transfusion in cardiac surgeries- including autologous transfusion
Patient Blood management in surgery
Allogenic Transfusion
Autologous Transfusion- Intra And Postoperative Red Cell Salvage, Haemodilution
Blood Substitutes
Haematopoietic Factors
Antifibrinolytics
Fibrin Sealants
Conjugated Oestrogens.
AABB pretransfusion testing schemes
Type and screen
Maximum surgical blood ordering schedule
transfusion trigger for surgery
factor replacement in surgery
autologous transfusion
cell salvage
perioperative
massive transfusion protocol

1. Transfusion support in Surgery Moderator- Dr. anshul Gupta

2. INDEX AABB indications Elective surgeries- Maximum surgical blood ordering schedule Anemia and surgery- including Transfusion Trigger Surgery and coagulation disorders- including factor replacement Transfusion in cardiac surgeries- including autologous transfusion Patient Blood management in surgery

3. In general surgery, blood transfusions are given to improve oxygen delivery to tissues, based on the patient's physiological requirements. Under normovolemic conditions, the body responds to a loss of haemoglobin by increasing the cardiac output , which affect hemodynamics during surgery.

4. Indications for Transfusion in surgery Severe haemorrhage Preoperatively anaemia correction During major operation in which blood loss is inevitable Postoperative anaemia To arrest haemorrhage or as a prophylactic measure prior to operation in patients with haemorrhagic status Anaemia from chronic surgical conditions

5. Some surgical transfusion strategies include: Allogenic Transfusion Autologous Transfusion- Intra And Postoperative Red Cell Salvage, Haemodilution Blood Substitutes Haematopoietic Factors Antifibrinolytics Fibrin Sealants Conjugated Oestrogens.

6. I. AABB Indications In 2012, the American Association of Blood Banks (AABB) published their clinical practice guidelines on the transfusion of RBCs, with recommendations graded according to their level of evidence: (1) The AABB recommends adhering to a restrictive transfusion strategy . In adult and paediatric ICU patients, transfusion should be considered at Hb concentrations of 7g/dL or less. Quality of evidence: high; strength of recommendation: strong.

7. (2) In hospitalized, haemodynamically stable patients with pre-existing cardiovascular disease , the AABB suggests adhering to a restrictive transfusion strategy. Transfusion should be considered at a Hb concentration of 8g/dL or less or for symptoms (chest pain, orthostatic hypotension or tachycardia unresponsive to fluid resuscitation, or congestive heart failure). Quality of evidence: moderate; strength of recommendation: weak.

8. (3) In hospitalized, haemodynamically stable patients with acute coronary syndrome , the AABB cannot recommend for or against a liberal or restrictive RBC transfusion threshold. Further research is needed to determine the optimal threshold. Quality of evidence: very low. (4) In hospitalized, haemodynamically stable patients, transfusion decisions should be influenced by symptoms as well as haemoglobin concentration.

9. These recommendations are applicable in most postoperative patients, and also in non-surgical patients, with the exception of patients with acute coronary syndrome. Transfusion should also be restricted in patients following an autologous blood transfusion programme .

10. II. Transfusion practice in elective surgeries Nowadays there is minimum blood loss during surgery because of meticulous surgical techniques, use of tourniquets, use of vasoconstrictors, use of antifibrinolytic drugs and good anaesthetic techniques. For effective utilization of blood during surgical procedures and haemorrhage , the clinician should have the knowledge about the blood volume of an individual which is about 70 ml/kg in an adult male, 66 ml/kg in an adult female, 80 ml/kg in children and 85 ml/kg in neonates .

11. Other points of consideration before transfusion An average healthy individual with normal cardiovascular system can withstand a loss of up to 500 ml of blood without any ill effects. A healthy average adult may lose up to 1000 ml of blood or even more without any ill effects, provided circulating blood volume is maintained by crystalloid or colloid solutions. Unnecessary transfusions especially of single unit of blood should be avoided in surgeries.

12. Role of Surgical Blood Ordering Practices in Elective Surgeries Component outdate rates are influenced by surgical ordering practices. For example, when RBC units are crossmatched for surgical patients, the shelf life of the unit is shortened if the component is unused. When crossmatch to-transfusion (C:T) ratios are monitored, a C:T ratio of >2.0 may indicate excessive ordering of crossmatched blood . One approach to reducing excessive C:T ratios is to identify procedures that do not typically require blood, and use this information to develop guidelines for the use of type and screen units instead of crossmatched units.

13. The policy of type and screen should be adopted universally for all patients even if they don't currently require blood (e.g. cholecystectomy). The request for single unit of blood in surgery is a common practice in India which by and large has been seen as an act of thoughtlessness. To avoid this- Transfusion trigger may be lowered to 7.5 gm/dl of Hb and should be based on the rate of development of anaemia and assessment of its effects on prognosis. Each blood transfusion service should frame its Maximum Surgical Blood Order Schedule

14. III. Anemias and surgery Most of the patients of elective surgery are anemic which are mostly Nutritional deficiencies (iron and folate). Many clinicians now accept the Hb of 7.5 g/d as transfusion trigger or the preoperative Hb threshold in a well-compensated patient presenting for surgery.

15. A higher pre-operative Hb level is required for elective surgery in following situations:- Inadequate compensation for anemia and the oxygen supply to tissues- Evidence of angina Increasing dyspnea or dependent oedema Patients with co-existing cardio respiratory disease like ischemic heart disease Major surgery or anticipated significant blood loss. Blood transfusion should rarely be used preoperatively to facilitate elective surgery.

16. Transfusion Trigger- Surgery T he intraoperative transfusion strategy should be based on patient’s Hb or haematocrit concentration, amount of blood loss, haemodynamic changes or end-organ ischaemia . They recommended a Hb target 7.0–9.0 g/dL and a transfusion trigger of 7.5 g/dL. The transfusion trigger for patients on cardiopulmonary bypass with moderate hypothermia and those at risk of critical end-organ ischaemia is 6.0–7.0 g/dL . In case of ongoing bleeding, a haematocrit of less than 30% is recommended as a transfusion trigger.

17. Haemoglobin trigger in Cardiac surgery The Society of Thoracic Surgeons and Society of Cardiovascular 2011 guidelines recommended PRBC transfusion for Hb <6 g/dL during cardiopulmonary bypass and <7 g/dL post-operatively , except in patients at risk for decreased cerebral oxygen delivery, for whom a higher Hb level is recommended. A restrictive Hb of 7-8 gm/ dl ( Hct 21-24%) with a patient maintaining an adequate O2 delivery > 273 ml O2/min/m2 can be considered during cardiopulmonary bypass.

18. IV. Surgery and coagulation disorders Diagnosis and treatment of coagulation disorders prior to any surgical procedure by haematologist is important to prevent excessive operative blood loss, which may lead to uncontrolled haemorrhage during surgery. INR should be less than 2 before surgery commences. Some drugs like aspirin and NSAIDS interfere with platelet function , thus stopping of such drugs 5-6 days before surgery can significantly reduce operative blood loss.

19. Factor replacement in surgery Factor replacement on demand shall be performed during spontaneous or traumatic bleeding episodes Dose (Factor VIII): Bleeding into joints and muscles (30-40 IU/kg) life-threatening (80-100 IU/kg), surgery (major bleeding 80-100 IU/kg) minor wounds (50-100 IU/kg)

20. For surgical prophylaxis, F actor VIII and IX levels should be maintained above 50% for 7-15 days after surgery The plasma fibrinogen levels of at least 1 g/L should be aimed from beginning prior to surgery and continued till wound healing.

21. Albumin in Surgery Cardiac surgery: Last choice of treatment after crystalloids and non-protein colloids •Major surgery: Not in the immediate postoperative period. The only indication for use is albumin less than 2 g/dL after normalization of circulatory volume

22. V. Blood transfusion in cardiac surgery Autologous blood transfusion is the most commonly used transfusion protocol. A cute isovolemic haemodilution improves microcirculatory blood flow due to decrease in the viscosity of blood. Use of cell saver machine helps to use the intra-operative mediastinal shed blood safely. There is no indication to use freshly drawn blood . The concept that transfusion of fresh blood reduces bleeding during cardiac surgery is no longer accepted. Blood components- platelets or FFP are not routinely used during cardiac surgery.

23. Pre-operative transfusion in Surgery Preoperative erythrocyte transfusion is not routinely recommended in elective surgeries. However, it is used in emergency surgery and life-threatening anaemia . Oral or intravenous iron alone may be considered in mildly anaemic patients (women- Hb 10–12 g/dl; men- Hb 10–13 g/dl) or in severely anaemic patients (both genders, Hb < 10 g/dl) to improve erythropoiesis prior to surgery. Erythropoietin with iron supplementation should be considered to reduce postoperative transfusions in patients with non-iron deficiency (e.g., EPO, vitamin D or folate)

24. Pre-operative autologous blood donation In patients posted for elective surgery with Hb > 11 gm/dl and without severe aortic stenosis or an acute coronary syndrome within 4 weeks. Some of the indications of preoperative autologous blood deposit may include: • Orthopaedic surgery (joint replacement) • Plastic and reconstructive surgery • Cardiovascular surgery • Major abdominal surgery (elective splenectomy) • Individuals with rare blood group/ with multiple alloantibodies/antibodies to high-frequency antigens

25. Contraindications for preoperative autologous blood donation : • Bacteraemia and/or acute localized infection • Myocardial infarction in the past 6 months • Unstable angina / angina at rest • Aortic stenosis • Congestive heart failure • Significant ventricular arrhythmia • Marked uncontrolled hypertension • Cerebrovascular accident within 6 months • Transient ischemic attack

26. Perioperative autologous blood donation Acute normovolemic haemodilution: It involves removing whole blood from the patient into a standard blood bag containing anticoagulant, either immediately before or shortly after the induction of anaesthesia in the OT with the maintenance of normovolemia using crystalloid and colloid replacement.

27. Perioperative Reinfusion: Patients of ANH should be monitored regularly during surgery, and the decision of reinfusion depends on the anaesthesiologist’s / surgeon’s assessment of blood loss. Usually, blood is reinfused when haemoglobin level falls in the range of 7-8 g/dl. The units of blood are reinfused to the patient in the reverse order of collection- This allows the most concentrated unit to be transfused at the time of least bleeding. Hence, the first unit, containing the highest haemoglobin , the maximum number of platelets and undiluted coagulation factors, is administered last.

28. Intraoperative blood salvage The process of collecting shed autologous blood and its processing and re-administration has been termed as cell salvage, auto transfusion, intraoperative blood recovery, and cell saving. It can happen either in the intraoperative period or in the post-operative period. Salvage involves washing of the collected blood, or it may be simply re-administered with micro aggregate filtration. Blood salvage in surgical procedures is recommended if there is the expectation of a significant blood loss (greater than 1 litre).

29. Postoperative blood salvage Postoperative blood salvage refers to collecting blood from surgical drains and subsequent reinfusion through a 40-micron microaggregate filter, with or without washing. These techniques available for collecting the postoperative drainage are usually of worth if blood collection can be done within 24 to 48 hours after surgery in patients actively bleeding into a closed site. This practice is generally limited to cardiac and orthopedic surgery.

30. Transplantation surgeries Before surgery, a crossmatch between recipient serum and donor lymphocytes is required. The ASHI Standards for Accredited Laboratories requires that the crossmatch be performed using a method that is more sensitive than routine microlymphocytotoxicity testing, such as prolonged incubation, washing, augmentation with AHG reagents, or flow cytometry Because HLA antibody responses are dynamic, the serum used for the crossmatch is often obtained within 48 hours of surgery for sensitized potential recipients and is retained in the frozen state for any required subsequent testing. An incompatible crossmatch with unfractionated or T lymphocytes is typically a contraindication to transplantation surgeries.

31. Equipments common in surgical transfusions Blood warmers are used when rapid transfusion of components is required, especially in massive blood loss during surgery settings. Microaggregate filters are typically used for the reinfusion of shed autologous blood collected during or after surgery.

32. VI. Patient Blood Management The concept of patient blood management introduced by the WHO in 2011 is a systematic approach focused on weighing the benefits of transfusion against the risk , with minimal transfusion-related adverse events. Perioperative blood management is based on a thorough preoperative assessment of patients by correcting any reversible cause of anaemia instead of going for allogenic transfusion. Preoperative blood transfusions are recommended only in patients with persistent bleeding, urgent or emergency surgery or cancer-related surgery where surgery cannot be delayed.

33. References AABB (Association for the Advancement of Blood and Biotherapies) Technical Manual, 21st edition, 2023 Modern Blood Banking & Transfusion Practices. Denise M. Harmening 7 th Edition. 2019. Principles and practice of Transfusion Medicine by Dr. R. Makroo , 2 nd Edition (2019) Transfusion Medicine, Technical Manual. DGHS, Ministry of Health and Family Welfare Govt. of India. 3 rd Edition. 2022 Thankyou