|Year : 2014 | Volume
| Issue : 2 | Page : 93-99
Rationale use of blood and its components in obstetric-gynecological practice
Shakuntala Chhabra, Anu Namgyal
Department of Obstetrics Gynaecology, Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha, Maharashtra, India
|Date of Web Publication||11-Aug-2014|
Department of Obstetrics Gynaecology, Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha, Maharashtra
Source of Support: None, Conflict of Interest: None
Appropriate and rational use of blood/components is essential for ensuring availability for the needy as well as preventing risks of transfusion-transmitted diseases and saving resources. Rational use means providing the right blood or products, in the right quantity, to the right patient and at the right time, bridging demand, and supply gap. The safety, adequacy, and effectiveness can only be achieved if unnecessary transfusions can be prevented. Further, risk can be reduced, but cannot be eliminated completely. Alternative to banked blood, autologous blood donation, normovolemic hemodilution, and intraoperative cell salvage should be considered as possible options. Recombinant factor VIIa is a new adjunct for treatment of massive hemorrhage and should be considered, if available.
Keywords: Blood transfusion, obstetric gynecologic practice, rationale use
|How to cite this article:|
Chhabra S, Namgyal A. Rationale use of blood and its components in obstetric-gynecological practice. J Mahatma Gandhi Inst Med Sci 2014;19:93-9
|How to cite this URL:|
Chhabra S, Namgyal A. Rationale use of blood and its components in obstetric-gynecological practice. J Mahatma Gandhi Inst Med Sci [serial online] 2014 [cited 2019 Jun 16];19:93-9. Available from: http://www.jmgims.co.in/text.asp?2014/19/2/93/138427
| Introduction|| |
Every day many lives are saved through blood transfusion (BT), which maintains the circulating oxygen-carrying capacity in various disorders, which include disorders of pregnancy, birth, postbirth, or gynecological diseases. However, statistics reveal that 74% of transfusions in adults are inappropriate , and critical appraisal is essential. The objective of this review is to understand the usage of blood and its products with maximum benefits and minimum side-effects to patients in hospital settings decreasing the indiscriminate use.
One common indication in women is severe anemia, prevalence of which in South Asian countries is high, highest in India with half of the global maternal deaths due to anemia.  It may be either due to gynecological disease or obstetric cause, nutritional or other reasons. Whatever the cause severe anemia in women is frequently treated with BT, however blood should only be used if there is cardiopulmonary dysfunction, not as a cure for anemia. Furthermore, these patients have normal blood volume and whole BT may cause circulatory overload, so packed red blood cells (PRBCs) should be given and the underlying disorder investigated and treated.
Normally, blood loss during birth is well-tolerated because of changes during pregnancy. In general, <15% loss results in minimal symptoms; 15-30% causes tachycardia; 30-40% shock; >40% loss leads to severe shock. With underlying diseases, even with <30-40% loss, blood is required.  The risk of mortality increases significantly in otherwise stable patients when the hemoglobin (Hb) falls to 3.5-4 g/dL, but in cases with ischemic heart disease with 7 g/dL.  So, obstetric hemorrhage is a major cause of perinatal and maternal mortality,  about 25-30% maternal deaths due to hemorrhage. Author has found obstetric hemorrhage contributing to 20% maternal deaths.  More than 4000 cases of severe hemorrhage are reported each year in the United Kingdom.  RCOG  also reports that hemorrhage is the leading cause of intensive care unit admissions. The occurrence of massive obstetric hemorrhage in developed and developing countries differs greatly, with the risk of death in developed countries 1:100,000, in developing countries 1:1000 births  Hemorrhagic shock produces a reduction in tissue perfusion, hypoxic metabolism, acidosis and deterioration in organ function, dyspnea, aggression or drowsiness and myocardial depression and accordingly it is classified and management planned with the clear need of BT [Table 1].
In obstetric practice, bleeding could be antepartum, intrapartum or postpartum. Gynecological disorders like abnormal uterine bleeding, leiomyoma or cancers also lead to heavy hemorrhage. Disseminated intravascular coagulation (DIC) which causes profuse bleeding occurs in cases of retained products of conception, eclampsia, amniotic fluid embolism, postpartum hemorrhage and abortion. The need for transfusion can be reduced by, preventing/treating anemia and blood loss; however, there are limitations to prevention and BT becomes essential.
| Blood Transfusion Services|| |
The challenge for BT services (BTS) is to provide quality services, containing costs and inappropriate use of blood squanders limited resources, creates an artificial shortage. A crossmatch:transfusion ratio (CTR) of 2.5:1 is generally accepted as efficient utilization of blood.  A study had revealed over crossmatching of varying degrees in various procedures, over transfusion 45.5% and case postponement rate of 18.1% indicating inefficient utilization of resources. Another study revealed the rate of inefficient utilization 9.0%. 
The maximum number of units transfused for each surgical procedure indicates the potential of severity of bleeding in that procedure, a useful guide for the need of crossmatched blood. The transfusion index of each surgical procedure, an index of blood requirement for that particular procedure helps in planning. 
| When to Transfuse|| |
Historically, patients are transfused to keep the Hb concentration 10 g/dL or more, but this needs a relook. A study has demonstrated decreased mortality in critically ill patients who were transfused at lower Hb thresholds.  Karpati et al.  have reported around 50% incidence of myocardial ischemia with Hb of 6.0 g/dL or lower, systolic blood pressure of 88 mm Hg or lower, diastolic blood pressure of 50 mm Hg or lower, and a heart rate >115 beats/min. Blood is needed for immediate transfusion in cases of excessive hemorrhage at birth with Hb <7 g/dL. Kalaivani et al.  advocates BT for pregnant women with Hb <5 g/dL who are symptomatic or have orthostatic hypotension irrespective of any other issue, however in practice, there is advocacy for transfusion with this Hb level, irrespective of symptoms, especially nearing date of birth. Determining the point, at which BT is essential, can be difficult. Many factors, including vital signs, ongoing blood loss, and coexisting disease need to be considered. In acute hemorrhage, BT should be initiated as soon as possible to offset the deficit. But blood should be transfused only when required to save a life and effective transfusion requires a minimum of two units for an adult. The decision to transfuse should be based on the risk for developing complications of inadequate tissue-oxygen delivery. With massive hemorrhage (blood loss >40%), it is essential to restore volume and oxygen-carrying capacity, by massive transfusion, (10 units of RBCs within 24 h, or 4-5 RBC transfusions within 1 h, replacement of one-half the patient's blood volume within 3 h).  Earlier Cosgriff et al.  had defined massive transfusion as "administration of >10 units of PRBCs." The massively bleeding patient must be assessed frequently to determine the efficacy of treatment as well as to identify correctable complications, bleeding or hemolysis.
| Pretransfusion|| |
Efforts should first be made to stabilize the patient without blood through prompt and appropriate supportive care, intravenous crystalloid or colloid solutions, and oxygen. The first treatment for hypotension, shock, and acute blood loss is volume expansion with normal saline (without dextrose), infused in a volume at least 3 times the volume lost  or 50 ml/kg followed by colloid solution, 6% dextran or 6% hydroxyethyl starch, given in equal volume to the blood lost, 6% dextran should not exceed 50 ml/kg body weight, and 6% hydroxyethyl starch 20 ml/kg body weight in 24 h. In acute cases, an early Hb will not reflect the severity of loss accurately until there has been adequate plasma volume replacement. Serial levels are required to determine the need for red cell transfusion.
| Preparing for Transfusion|| |
In an obstetric emergency where type-specific or crossmatched blood is not available, Rh-negative O group blood can be administered to prevent the risk of Rh sensitization. Crossmatched blood should be administered as soon as available because the estimated risk of a hemolytic reaction has been reported to be as high as 5%, although trauma patient's reports reveal lower complication rates. 
Response to massive hemorrhage needs a coordinated effort between clinicians and the blood bank. So, a massive hemorrhage protocol outlined before an emergency occurs, clinical drills on obstetric hemorrhage scenario etc are essential. 
In anesthetized patients, vital signs alone may be inadequate. Signs, symptoms, if possible and prior medical history, cardiopulmonary reserve, amount of anticipated blood loss, oxygen consumption and presence of atherosclerotic heart disease are all important. Prior to elective surgery, all efforts should be made to correct anemia, except for emergency, all patients getting anesthesia need to have minimum Hb of 8 g/dL. Cherian et al.  report that transfusion may be necessary with Hb <8 g/dL and blood loss of >1 L. Transfusion is not indicated as treatment of anemia postoperatively or postpartum in stable cases with no active bleeding.
| Procedure and Monitoring|| |
Both whole blood and PRBCs contain a small amount of citrate anticoagulant and an additional preservative. Blood collected in citrate phosphate dextrose (CPD) adenine-1 anticoagulant can be stored for up to 35 days and it is essential to start transfusion and return unused blood within 30 min of leaving the laboratory.
All transfusions should be given and monitored by clinician closely for the first 15 min for serious hemolytic reactions, with monitoring of the vital signs every 30 min and infuse for a maximum of 4 h.
| Components|| |
Red blood cells can be transfused either as whole blood or PRBC. A unit of whole blood is 400-500 ml, with a hematocrit of 45-55%, each unit of PRBCs, has 180-200 ml of RBCs, 50-70 ml of plasma and hematocrit of 60-70%. PRBCs are indicated in decreased oxygen carrying capacity or hypoxia due to inadequate red cell mass. RBC must be ABO-compatible. RBC transfusions should not be initiated in response to Hb estimation alone, or to an increase in heart rate and/or respiratory rate, as these may be normal compensatory mechanisms.
Platelets or fresh frozen plasma (FFP) should be given according to need. FFP is indicated for correction of coagulation abnormalities, micro vascular bleeding when prothrombin time (PT) and partial thromboplastin time are >1.5 times the mid-range normal reference value. ABO-compatible FFP is indicated for treatment of bleeding with multiple coagulation-factors deficiencies, massive transfusion with coagulation abnormalities, and bleeding due to warfarin therapy in a dose of 15 ml/kg if the PT is prolonged, and platelet concentrates (4-6 donor units for an adult) when the platelet counts fall below 20,000/mm 3 . If the platelet counts or coagulation profile are not available, two units of FFP and six units of platelet concentrate may be given for every six units of blood transfused within 24 h. 
Each unit of blood contains >5.5 × 10 10 platelets, approximately 50 ml of plasma, so four to eight units of concentrated platelets are needed for profound thrombocytopenia. Obstetrical patients with microvascular bleeding often require platelet transfusions when the platelet count is <50,000/mm 3 . Platelet transfusion is generally not indicated for patients with extrinsic platelet dysfunction (e.g., uremia), since platelets will also function inadequately. Prophylactic platelet transfusion is not effective for thrombocytopenia due to increased platelet destruction; the cause should be investigated and treated. One unit of platelets increases the platelet count by 5000-10,000 cells/μL in the absence of platelet destruction.  It is essential to know which component is needed, when and how much quantity and the precaution needed [Table 2]. While, it is possible to transfuse ABO-incompatible platelets, they may have a shorter life span.  Rh compatibility needs to be seen in obstetric population and Rh immune globulin is needed if Rh-positive platelets are administered to Rh-negative mother. 
Cryoprecipitate extracted from thawing FFP slowly, rich in factor VIII (FVIII) and fibrinogen is used to treat microvascular bleeding in the presence of fibrinogen deficiency, 150 mg/dL due to DIC or massive transfusion, with fibrinogen concentration less than 80-100 mg/dL essential for treatment of congenital fibrinogen deficiency or bleeding with von Willebrand's disease when factor concentrates are unavailable. Because cryoprecipitate has only a small amount of plasma, ABO-compatibility is not necessary. 
Activated recombinant FVII (rFVII), is a promising new alternative to blood component identical in structure and function to human FVIIa, originally developed to prevent or control bleeding in patients with hemophilia A or B with inhibitors to FVIII or FIX to augment the intrinsic clotting pathway by binding with tissue factor directly activating FIX and FX, and effective dose is 50-100 μg/kg intravenously every 2 h until hemostasis is achieved, majority of patients require only one dose.  However, we must ensure adequate platelets and clotting factors because rFVIIa increases clotting by acting on these substrates. Because rFVIIa is derived from recombinant technology and not from human proteins, so there is no risk of viral transmission, but thrombosis, including cerebrovascular accidents, myocardial infarction, pulmonary embolism, and clotting of indwelling devices are reported, most occur within 3 h of the last dose. 
Autologous blood donation
Two to four units of blood may be collected prior at least 7 days apart, and last at least 4 days before surgery, in case of elective surgery with Hb 10 g/dL or greater for her own use during surgery, autologous transfusion.  No single-unit autologous transfusion is advocated, and unused autologous units can be released into the general pool. 
Preoperative isovolemic hemodilution may be performed by removal of two or more units of blood and replaced with an equal volume of crystalloid to improve tissue perfusion during surgery and make blood available during and after surgery. It is a viable option for peripartum hemorrhage risk, especially for those with rare antibodies difficult to transfuse with compatible homologous blood. It has minimal hemodynamic effects with maintenance of fetal umbilical artery systolic/diastolic ratio,  but cost discourages routine use. 
Yamada et al.  report that women with placenta previa who did not donate blood prepartum had a 4 times greater rate (12% vs. 3.1%) of peripartum homologous BT and recommend donation at 32 weeks' gestation with removal of 400 ml/week for storing volume of 1200-1500 ml Fuller and Bucklin,  report higher overall rate of BT, highest with autologous blood donor 71% receiving blood peripartum compared to 12% who received homologous blood. Autologous blood has smaller incidence of bacterial contamination. 
Acute normovolemic hemodilution
It involves the collection of autologous blood immediately before surgery or delivery, maintained by intravenous fluid administration with colloids or crystalloids, colloid equal to blood withdrawn, crystalloid, 3 times of blood removed.  When blood is subsequently lost, it has less RBC mass and the blood removed can be returned. Monk  reported that because the blood is collected and stored at the bedside for immediate reinfusion, the risks of bacterial contamination and administrative error associated with autologous blood storage are significantly reduced and no patients had nausea, vomiting, dizziness, or lightheadedness, abnormalities in vital signs or fetal heart rate in his series.
| Intra-operative Cell Salvage|| |
Blood shed within the surgical field retrieved by an anticoagulated suction apparatus and collected within a reservoir from where it is centrifuged, washed, and pumped into an infusion bag and returned to the patient later, is effective in reducing the need for allogenic red cell transfusion. , Cell salvage is recommended where an intraoperative blood loss of more than 1500 ml is anticipated. Cell salvage should only be used by the teams with expertise and experience. Contamination by amniotic fluid, risks of amniotic fluid embolism, and anti-D formation are genuine concerns.  However, in a multicenter historical cohort study with 139 autologous BTs during cesarean delivery through intraoperative cell salvage technique, no acute febrile illness or adult respiratory distress syndrome was reported. 
While patients are often highly concerned about the infectious risks, there is more risk of ABO-incompatibility and similar mix ups, unrelated to infections. In many cases, multiple errors are involved, phlebotomy, patient misidentification, sample mislabeling, and laboratory errors.  Vigilance is imperative.
| Risks of Blood/Component Transfusion|| |
Transfusion may be a lifesaving procedure but is not without risk. 1% of all transfusions lead to some adverse reaction. Although many measures are taken to reduce risks, donor risk screening, laboratory testing, it is not possible to have zero risk, because of immunological or nonimmunological mechanisms, immediate, and delayed.
Recipients may develop transfusion-transmitted infection, immunological complications. Massive transfusion is associated with the vicious cycle of metabolic acidosis, abnormalities of coagulation, biochemistry, and hypothermia. The treatment of the hemorrhage with red cell transfusion can worsen the coagulopathy by diluting platelets and clotting factors as well as contributing to hypothermia and acidosis. 
It is most serious complication arising from erroneous transfusion due to recipient's circulating antibodies destroying the donor's RBCs characterized by fever, urticaria, nausea, chest and flank pain, hyperkalemia, hypotension, DIC, hemoglobinemia, and acute renal failure. ,
Petrovich  reported that a delayed hemolytic reaction occurs because of extravascular hemolysis of donor erythrocytes in the presence of antibodies from previous transfusions or pregnancy in recipient serum that were at levels too low to be detected during the crossmatch. Clinical manifestations occur approximately 1 week after a seemingly compatible transfusion and are characterized by anemia, mild fever, increased unconjugated bilirubin, jaundice, hemoglobinuria, decreased haptoglobin, and spherocytosis with self-limited symptoms. 
Transfusion-transmitted infectious disease
The incidence of transfusion-transmitted infectious diseases has decreased dramatically, because of improved donor screening for viral pathogens, such as HIV, hepatitis C, hepatitis B, etc. 
Researchers reported West Nile Virus first in 2002 and prompted the nucleic acid testing, specially in locales with high West Nile Virus activity. , Variant Creutzfeldt-Jakob disease More Details is an emerging concern, with one probable case of transfusion-associated transmission prompting exclusion of blood donors who had spent more than 6 months in the United Kingdom. Researcher also reports that Trypanosoma cruzi, cause of trypanosomiasis (Chagas' disease), can also be transmitted, a growing concern in the United States because the parasite can survive cryopreservation of blood products. Bacterial contamination of blood products is the most common cause of acute transfusion-associated mortality from an infectious agent. Goodnough et al.  report that bacterial contamination occurs most often with platelets, with an estimated incidence of one for every 12,000 units of blood administrated because platelets must be stored at room temperature and so have a higher potential for supporting bacterial growth. The most frequent contaminating organism is Yersinia More Details entercolitica for RBCs and Staphylococcos aureus for platelets.  The clinical presentation ranges from mild fever to acute sepsis leading to death. Bacterial contamination should be suspected and antibiotic therapy considered in patients who develop fever within 6 h after platelet transfusion.
Transfusion-associated acute lung injury
Transfusion-associated acute lung injury, an acute respiratory distress syndrome which can occur within 2-6 h after transfusion ,, is estimated to occur once in every 2000-5000 transfusions of blood or blood products,  leading cause of death from transfusions in the United States; pathogenesis is antibody-mediated. 
Petrovich  reported that other complications can occur due to the CPD, anticoagulant preservative. In massive transfusion, citrate can bind plasma calcium and lead to hypocalcemia, causing hypotension, tetany, and cardiac arrhythmias. Plasma calcium levels should be measured during massive transfusion and hypocalcemia treated with intravenous calcium chloride. Acidosis can occur (pH < 6.9) during storage because of the metabolism of glucose to lactate.
Hyperkalemia can occur with PRBC administration because of passive diffusion of potassium out of the RBCs during storage, however with normal renal function; the excess potassium is transported back into the cells or excreted in the urine. Because blood is stored at 1-6°C, hypothermia can result, especially during massive transfusion.
| Conclusion|| |
The present review reinforces the importance of justified and appropriate use of blood and its products in the clinical setting. Judicious implementation of guidelines for use of various blood products may help decrease the inappropriate use of blood and its components.
A hospital BT committee of representatives from service users can formulate steps to improve the quality, optimize expenditure and blood usage. It could ensure the replacement of routine compatibility testing by the "type, screen and hold" procedure for procedures with CTR's more than 2.5, low transfusion indices (<0.5)-as well as a low number of maximum blood units transfused.  Guidelines are essential to assist clinicians in identifying indications for blood use and triggers for transfusion, ensure the quality BTS and practices. BTS need to oversee all policies and procedures relating to blood utilization, staff education, and training on BT practices. 
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[Table 1], [Table 2]