INVITATION ARTICLES - Blood Transfusion In Obstetrics and Gynecology - By DR. SUGUNA. R. KUMAR

Professor of OBG,
Al-Ameen Med College,
Bijapur, Karnataka.


There are many controversies regarding blood transfusion. Like when to transfuse? What to transfuse? And How much to transfuse?


The purpose and scope of Blood Transfusion are
• Maternal mortality due to obstetric hemorrhage is 25-30% and anemia is 15%, both these condition require blood transfusion.
• Studies show that there is inappropriate transfusion in 15-45%, either transfusion done in not indicated cases or too late or too little done in indicated cases.
• Rising cost and non availability of blood, risk of transfusion reaction, transmission of infections has made us to limit transfusion only in indicated cases.


Nowadays only blood components are used instead of whole blood.
The blood components are
-Packed red cells,
-Platelet concentrate,
-Fresh frozen plasma,
-Human plasma proteins like albumin, coagulation factor concentrates, Immunoglobulins.
-Specialized products: CMV negative or leuko-reduced blood and Type specific or HLA matched platelets.


Adverse effects of blood transfusion are:

1) Transfusion reaction:
Non hemolytic reaction: fever, chills, urticaria occurs in 1-5% of all transfusion
Hemolytic reaction: due to incompatible blood is a life threatening complication
2) Transfusion-transmissible diseases: HIV-1, HIV-2, hepatitis B and C, other hepatitis viruses, syphilis, malaria, CMV, brucellosis, Chaga’s disease.
3) TRALI- transfusion related acute lung injury, where injury to pulmonary capillaries by lipid products stored components, leukocyte reaction.
4) Bacterial contamination of blood

Always follow Guidelines before blood transfusion.
Guidelines offer guidance about appropriate use of blood products, so that neither the women is compromised nor exposed to unnecessary risk.


-RCOG Guidelines. 2007. formulated from databases of randomized controlled trials, systemic reviews and meta-analysis from 1966-2006 from the Cochrane library, TRIP, Medline and PubMed.
-WHO Guidelines, Geneva. 2001.
-American Society of Anesthesiologist Task Force on Blood Component Therapy, 1996 which included 9 anesthesiologist, one physician, college of American pathologist, ACOG and methodologist. Based on 160 studies on use of blood component in perioperative and peripartum period.


WHO prescribes a checklist before prescribing Blood:

1) What improvement in the patient’s condition am I to achieve following the blood transfusion?
2) Can I minimize the blood loss to reduce the transfusion?
3) Are there any other treatment like I.V replacement fluid and oxygen?
4) What are the specific clinical and lab indications for transfusion?
5) What are the risks of transmitting infectious agent?
6) Do the benefits of transfusion reaction outweigh the risks?
7) What other options are there if no blood is available in time?
8) Will the trained person monitor and respond immediately if any acute transfusion reactions occur?
9) Have I recorded my decision and reasons for transfusion on patient’s chart and the blood request form?


RCOG recommends reduction of blood transfusion by:

1) Treatment of ANEMIA must.
2) Hb% of 10.5g/dl indicates hematinic deficiency, exclude hemoglobinopathies.
3) Oral iron preferred in the treatment of anemia. Parental iron only in intolerance to oral, absorption defects, doubtful compliance of patient.
4) Recombinant human erythropoietin (rHuEPO) used only in end stage renal disease.
5) Hemoglobinopathies and bone marrow failure syndrome treated by blood transfusion in close conjunction with hematologist.
6) Active management of 3rd stage or labour proved to decrease incidence of blood transfusion.
7) High risk of hemorrhage patients advised hospital delivery only.
8) Optimal management of women on anticoagulants.


General principles of blood transfusion are (RCOG)

- Blood grouping and antibodies should be done at booking and at 28weeks.
- Patient blood sample for cross matching should be ideally fresh, group and save sample in case of high risk patients (placenta previa, accrete), sample should not be more than 7 days old.
- Only Kell negative blood should be used in women of child bearing age.
- CMV seronegative red cells and platelets for seronegative women.
Minimize the use of banked blood by
- Pre- autologus deposit of blood. In pregnancy this is not advice.
- Acute normovolemic hemodilution: Removal of predetermined volume of blood prior to surgery, replaced by crystalloids and subsequent reinfusion of the removed blood.
- Intraoperative blood salvage: If blood loss of >1500ml expected. In pregnancy there is a risk of amniotic fluid embolism and contamination with fetal cells.
- Autologus blood transfusion in ruptured ectopic and reactionary hemorrhage in postoperative cases.


Normal blood volume is 7% of ideal body weight and it increases to 8-9% in pregnancy.
Massive blood loss is loss of 1 blood volume in 24hours or 50% of blood volume loss in 3hours or loss at a rate of 150ml/minute.

Clear protocol to manage obstetric hemorrhage involving obstetrician, anesthetist and hematologist and blood bank is recommended. This should be practiced in ‘fire drills’ with trained personnel. (RCOG)

In hemorrhagic shock primary compensation is by increase in cardiac output, autonomous nervous system preserves oxygen delivery to CNS and heart, sparing the skin, fat, kidneys. Thus changes in the microcirculation affects oxygen transport at the tissue level. Urine output is most important in monitoring the circulation.


Clinical features of hemorrhagic shock:
- Class I hemorrhage: - with loss of 15% of total blood volume, little hemodynamic affect occurs; there is vasoconstriction and mild tachycardia.
- Class II hemorrhage: - with loss of 15-30% of total blood volume there is tachycardia, decrease in pulse pressure, anxiety and restlessness
- Class III hemorrhage: - with loss of 30-40% of total blood volume there is marked tachycardia, tachypnea, systolic hypotension, altered mental status. Young healthy women can still be treated with crystalloid therapy but blood transfusion also recommended.
- Class IV hemorrhage:- with loss of >40% of total blood volume marked tachycardia and hypotension, narrow pulse pressure, low urine output depressed mental status if not treated with crystalloids and blood is life threatening.

Estimation of blood loss is always inaccurate. Visual estimation of blood loss is not reliable because of inaccuracy in blood loss measurement, intercomparmental fluid shift during shock and dilution effect of crystalloid therapy also make hematocrit estimation not reliable method. Thus clinical evaluation of the patient is most important in the management of hemorrhagic shock


Factors affecting the response to decrease Hb in hemorrhage are:

- Cardiopulmonary reserve – depending on the preexisting cardiac and pulmonary disease and hemodynamic indexes, this is also affected by drugs and anesthetics administered.
- The rate and the magnitude of blood loss.
- Oxygen consumption is affected by the body temperature, drugs, anesthetics, sepsis, and muscular activity of the patient.
- Preexisting atherosclerotic disease.
- Anemia (normovolemic hemodilution) and preeclampsia (hemoconcentration)


Management of Obstetric hemorrhage:

1) Identify the cause of hemorrhage.
2) Two I .V started of large caliber.
3) Fluid replacement by crystalloids 3 times the estimated blood loss, rapid equilibration occurs, 20% seen in circulation after 1hour. Survival reduced in hemorrhage managed with blood alone. 6% excess mortality in albumin (colloid ) treated non pregnant patients.
4) Blood replacement in class III & class IV hemorrhage. Compatible whole fresh blood is ideal (but not available) 70% of red cells function for 40days, coagulation factors present and plasma expands the hypovolemia.
5) Packed red cells and crystalloid infusion mainstays therapy in hemorrhage.
6) Transfusion of 1 unit of whole blood or RBCs increases hematocrit by 3% or Hb by 1g/dl in a non-bleeding adult.


• Thus blood transfusion is indicated only on clinical, hematological grounds and development of inadequate oxygenation (when Hb is between 6-10g/dl)
• Rarely done when Hb is 10g/dl and always indicated when <6g/dl
• 10/30 rule outdated (Hb-10g/dl, hematocrit of 30%), single unit transfer not beneficial, hazard and risks far outweigh the benefit of transfusion. (ACOG)
• Physiological markers of impaired tissue oxygenation is Oxygen extraction ration (O2E2) is superior, Oxygen extraction monitored continuously by using pulse oximetry (arterial O2 saturation) and mixed venous oximetry (venous O2 saturation)


Whether blood should warmed prior to transfusion?
Warming of blood not beneficial, if the rate of flow is >50ml/hr clinically significant cold agglutinins present then warm the blood. Blood warmer is ideal never use hot bowl causes hemolysis which is life threatening. Keeping the patient warm is important (WHO)

Does hypocalcemia occur with administration of blood?
With 4-5units of transfusion calcium binds with citrate preservatives. This is self resolving with metabolism of citrate by liver and kidney. Hypocalcemia will not impede blood coagulation. Hypocalcemia with hypothermia and acidosis is dangerous will decrease cardiac output, causes bradycardia and dysrhythmia thus calcium gluconate indicated here (WHO)



• Dilution coagulopathy occurs in major blood loss treated by volume replacement by crystalloids, colloid and transfusion of red cell component, stored whole blood.
• Obstetric conditions like amniotic fluid embolism, placental abruption, pre-eclampsia cause DIC, also in septic abortion secondary to tissue trauma which activates the coagulation cascade.
• Clinically suspect DIC when there is profuse bleeding from trauma site, oozing from IV insertion and venesection site.

Platelet transfusion

1 unit of fresh blood raises platelet count by 10,000-15,000/cumm. Transfusion of 1 platelet concentrate (50ml) increases the count by 5-10x109/l.


Platelet transfusion indicated in (RCOG)
- Count of <50x109/l, thrombocytopenia, platelet dysfunction and micro vascular bleed with adequate platelet count.
- Safe margin is to keep a trigger of 75x109/l
- 50x109/l anticipated when 2 volume replaced by fluids or 5-10 units of red cell component transfusion
- Good communication with the transfusion laboratory must.
- Rh-ve women should receive Rh-ve platelets. Group compatibility must. Anti D 250 IU is given if Rh+ve platelets given in Rh-ve women.
- Platelet transfusion not effective when thrombocytopenia is due to platelet destruction as in ITP, TTP, untreated DIC.
- Vaginal delivery and minor operative procedure can be done with platelet of <50x109/l.


Fresh frozen plasma (FFP)

FFP contains stable clotting factors, albumin, immunoglobulin and no platelet.
Full blood count (CBC) and coagulation screening advised before advising FFP
FFP takes 30 minutes to thaw, once thawed used in 6 hours.


RCOG recommends
- Infusion of FFP ideally before 1 blood volume is lost.
- In DIC a combination of FFP, platelets and cryoprecipitate indicated
- FFP indicated when fibrinogen is <100mg/dl and maintain fibrinogen >1g/dl.
- FFP and cryoprecipitate ideally should be of same group of the recipient. No need of anti-D prophylaxis in Rh-ve.
- FFP administered as 12-15ml/kg, to keep the activated partial thrombhoplastin time (aPTT) and PT time ratio <1:5.
- Contraindicated for augmentation of plasma volume or albumin concentration.


It is cold precipitable protein fraction derived from thawed FFP AT 1-6º C. Contains factor VIII, fibrinogen, fibrinonectin, vW factor and factor XIII.
1unit/kg body weight raises plasma fibrinogen by approximately 50mg/dl in the absence of consumption or massive bleeding.

Cryoprecipitate indicated in (ACOG)
- in von Willebrand’s, unresponsive to Desmopressin and congenital fibrinogen deficiency in perioperative or peripartum period
- Bleeding with fibrinogen of 80-100mg/dl.


Recombinant factor VIIa (rFVIIa) therapy
Can be considered in life threatening PPH but this should not delay life saving procedure for PPH. Whether it reduces blood loss during Caesarean section is doubtful. It has a pivotal role in initiating coagulation but efficacy and safety still to be established. One can consider keeping a stock in the blood bank.


Anemia in pregnancy
It is a normovolemic; oxygen delivery is adequate even at Hb of 7g/dl. Anemia tolerated well even at a hematocrit of 18-25%, myocardial lactate flux not affected with Hb 6g/dl. Heart failure occurs only when hematocrit is <10%. Chronic anemia is better tolerated. There is increase in 2,3-diphosphoglycerate in RBCs which facilitates oxygen delivery. There is no change in cardiac output until Hb <7g/dl. Obstetric women tolerate well with no adverse affect on mother and fetus.
Thus blood transfusion is indicated in antenatal period if Hb is <6g/dl four weeks prior to delivery where there is no time to give iron. This improves anemic status and oxygen carrying capacity to withstand the strains of labour and blood loss during labour. When Hb is <7g/dl in labour or immediate post partum period, blood transfusion depends on the medical history, age and symptoms. Fit and healthy women require no blood transfusion even with Hb of <7g/dl. Exchange transfusion rarely done, only in desperate cases of cardiac failure with anemia, severe anemia requiring surgery, severe anemia with hematocrit of 13% near term. In sickle cell anemia repeated transfusion indicated thus partial exchange transfusion done. In patients who refuse blood transfusion or Jehovah’s witnesses optimize Hb before delivery. Antenatal planning required to keep Hb above 10.5g/dl. Blood sparing techniques are acceptable in these patients.


The risk of bleeding depends on the extent and the type of surgery and the ability to control bleeding and the consequence of uncontrolled bleeding. Reduction of operative blood loss is very important to prevent blood loss during any surgery.

- Improvement in surgical techniques like prompt ligation of bleeding points, diathermy and local hemostatic agents can be used.
- Use of vasoconstrictors and tourniquets
- Use of antifibrinolytic agents.
- Improved anesthetic technique like preventing episodes of hypertension and tachycardia, avoiding hypercarbia, regional and hypotensive anesthesia help in decreasing blood loss during surgery.


Increasing demand and non availability of blood has brought Blood analogues still in research process like
- cell-free purified hemoglobulin solution
- Perfluorocarbon emulsions a inert liquid with high oxygen solubility, oxygen delivered by simple diffusion.
- Liposome-encapsulated hemoglobin.


Auditable standards recommended by RCOG:
- Are there local protocols for the management of massive hemorrhage in your institute in obstetrics?
- Are relevant staffs familiar with the protocol?
- Review the situation to ensure whether the communication chain worked and no delay in providing blood products?


Thus judicious use of the optimum blood component only when indicated, in proper dosage and appropriate follow up studies can lead to better transfusion practices. This also decreases the morbidity and mortality and provides optimal patient care.



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