Blood Transfusion in Clinical Practice

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Indications for Red Cell Transfusion
• While defining indications for red cell transfusion, one
cannot base it only on the values of haemoglobin (Hb) and
haematocrit (Ht). Firstly, one has to evaluate patient’s age,
nature of disease and co-morbidities, expected surgical
procedures, coagulation abnormalities, the amount of blood
expected to be lost because of bleeding, clinical and physio-
logical parameters, showing an overall condition of a patient
and tolerance to an expected tissue hypoxemia due to
anaemia.
• What is more, one must take into consideration is body
temperature, heart function, heart rate, arterial blood
pressure, renal function, venous blood oxygen saturation,
and blood oxygen partial pressure.
• The main indication for red cell transfusion is to keep
adequate oxygen-carrying capacity of blood and to avoid
or reduce tissue hypoxia. The red cell transfusion should
not be done only to increase the Hb level (except the cases
of severe symptoms of anaemia and the need to ameliorate
the oxygen-carrying capacity).
• In case of anaemia, the delivery of oxygen is ameliorated by
physiological adaptability mechanisms: The haemoglobin
affinity for oxygen decreases, oxygen-haemoglobin dissocia-
tion curve shifts to right, oxygen release from red cells
increases, peripheral vascular resistance and blood viscosity
decrease; furthermore, the cardiac output increases due to
increased heart rate, stroke volume and contractility.
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Blood Transfusion in
Clinical Practice
124

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Blood Transfusion in Clinical Practice
• The consumption of oxygen depends on these factors like
physical activity, body temperature, sympathetic and
metabolic activity, heart rate, and the effect of certain drugs
(e.g. anaesthetics).
• Young and healthy women without hypovolemia can tolerate
acute anaemia quite well. The delivery of oxygen remains
adequate, and there may not be severe symptoms of anaemia
even though Hb concentration decreases to 6 g/dL.
• When treating major haemorrhage, firstly, the volume of lost
blood should be estimated. The goal of maintaining adequate
tissue perfusion is normovolemia; therefore, one of the
main principles in treating acute bleeding is to restore circulat-
ing blood volume by fluids, but not by red cell transfusion.
PCV/Hb should not be considered as the only laboratory
markers when estimating bleeding level, because these
markers can be influenced by the initial infusion therapy.10
• The average adult blood volume represents 7% of body
weight (or 70 mL/kg of body weight). Estimated blood
volume (EBV) for a 70 kg person is approximately 5 litres.
Blood volume varies with age and physiologic state. Older
individuals have a smaller blood volume. Children have
EBVs of 8–9% of body weight, with infants having an EBV
as high as 9–10% of their total body weight.11
Blood Transfusion in Anaemia
In chronic anaemias, red cell transfusion is given according
to the Hb level which is given below:
• Hb >10 g/dL, if patient’s condition is stable—no indication
for red cell transfusion.
• Hb <6 g/dL, transfusion almost always indicated.
• Hb 6–10 g/dL, indication for transfusion is based on any
ongoing indication of organ ischemia, the rate and magni-
tude of any potential or actual bleeding, the patient’s intra-
vascular volume status and risk of complications due to
inadequate oxygenation.
• When Hb level is less than 7 g/dL and anaemia is asympto-
matic, transfusion is needed if massive bleeding is expected
during surgery or the patient belongs to a high anaesthetic
risk group.

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The AABB guidelines include the following recommenda-
tions.12
• Hb <6 g/dL: Transfusion recommended except in exceptional
cases.
• Hb 6 to 7 g/dL: Transfusion generally likely to be indicated.
• Hb 7 to 8 g/dL: Transfusion in postoperative cases.
• Hb 8 to 10 g/dL: Transfusion generally not indicated except
in exceptional cases (e.g. ongoing bleeding, acute coronary
syndrome with ischemia, etc.).
• Hb >10 g/dL: Transfusion generally not indicated except in
exceptional cases.
According to Kenyan Government, 2004 Guidelines for the
Appropriate Use of Blood and Blood Products13 is given below.
• Red cell transfusion is rarely indicated when haemoglobin
levels are greater than 10 gm/dL, and is usually indicated
when haemoglobin concentrations are less than 5 gm/dL.
However, even severely anaemic patients (less than 5 gm/
dL Hb) who are clinically stable may not require transfusion.
• Transfuse only to decrease symptoms and to minimize risk
(generally at Hb of less than 5 gm/dL). Do not transfuse
above 5 gm/dL Hb unless patient is symptomatic.
• Treat nutritional and mild blood loss anaemia with specific
therapeutic agents as indicated (iron, folic acid, B12).
Use specific strategies for sickle cell disease and thalassemia.
One unit of donor erythrocytes (around 250 mL), the usage
of blood components in a 70 kg patient increases Hb by about
1 g/dL and PCV by 3%.
A unit of whole blood has a volume of approximately 400 to
500 mL, with a haematocrit of 45 to 55%. A unit of PRBCs
consists of the red blood cells concentrated from a unit of whole
blood. Each unit of PRBCs contains approximately 180 to
200 mL of RBCs and 50 to 70 mL of plasma. The haematocrit
of PRBCs is 65 to 75%.
Red cell transfusion in blood loss
• Loss of <15% of circulating blood volume (CBV) (up to 750 mL):
No need to transfuse red cells, unless anaemia or severe heart
or pulmonary diseases were diagnosed before haemorrhage.

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Blood Transfusion in Clinical Practice
• Loss of 15–30% of CBV (around 750–1500 mL): Crystalloids
and synthetic colloids should be given; usually there is no
need for red cell transfusion, unless anaemia or severe
heart or pulmonary disease is diagnosed and the bleeding
continues.
• Loss of 30–40% of CBV (around 1500–2000 mL): Hypovolemia
is corrected by crystalloids and synthetic colloids and red
cell transfusion is usually indicated.
• Loss of >40% of CBV (>2000 mL): Urgent correction of hypo-
volemia, including red cell transfusion, must be performed.
Haemorrhage is broken down into four classes by the American
College of Surgeons.14
• Class I Haemorrhage involves up to 15% of blood volume.
There is typically no change in vital signs and fluid resuscita-
tion is not usually necessary.
• Class II Haemorrhage involves 15–30% of total blood
volume. A patient is often tachycardic (rapid heart beat)
with a narrowing of the difference between the systolic and
diastolic blood pressures. The body attempts to compensate
with peripheral vasoconstriction. Skin may look pale and
be cool to the touch. The patient may exhibit slight changes
in behavior. Volume resuscitation with crystalloids (saline
or Ringer’s lactate) is all that is required. Blood transfusion
is not typically required.
• Class III Haemorrhage involves loss of 30–40% of circulating
blood volume. The patient’s blood pressure drops, the heart
rate increases, peripheral hypoperfusion (shock) and the
mental status worsen. Volume correction with crystalloid
and blood transfusion are usually necessary.
• Class IV Haemorrhage involves loss of >40% of circulating
blood volume. The limit of the body’s compensation is
reached and aggressive volume correction is required to
prevent death.
• As a general rule, less than 15% loss of blood volume results
in minimal symptoms; 15 to 30% results in tachycardia; 30
to 40% in signs of shock; and greater than 40% in signs of
severe shock. Some patients with underlying diseases may

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Essentials of Blood Banking and Transfusion Medicine
require transfusion at 30 to 40% blood loss. Almost all
patients require transfusion with losses greater than this.
Massive Haemorrhage
Blood loss is considered massive if:
• All blood volume is lost within a 24-hour period.
(Normal blood volume in the adult is approximately 7% of
ideal body weight); or
• 50% blood volume loss within 3 hours; or
• A rate of loss of 150 mL/minute.
Management of massive blood loss
• Aggressive volume correction with colloids/crystalloids
(normal saline, Ringer’s lactate, dextrose).
• A combination of packed red cells, FFP and platelets are
indicated in 1:1:1 proportion. One proportion of platelets is
one therapeutic dose (4–6 units of RDPs) or one pack of SDP.
• FFP and cryoprecipitate ideally be of the same blood group
as that of the recipient.
Ways to minimize blood loss in massive haemorrhage
• Use of antifibrinolytic drugs
– Tranexamic acid (orthopedic and cardiac surgeries)
– Alprotinin
• Thrombo-elastography: Assesses dynamics of clot function,
clot aggregation, clot strength and stability of clot.
• Protamine in place of low molecular weight heparin.
• Recombinant VIIa can be given.
• Desmopressin can be used to release factor VIII and vWF.
Other Guidelines for Red Cell Transfusion
Transfusion guidelines from College of American Pathologists
(CAP)15
Target population: General.
RBC transfusion with following:
1. Hb <6 g/dL: Usually indicated.
2. Hb >10 g/dL: Rarely indicated.

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3. Hb 6–10 g/dL: Decision depends upon extent of blood loss.
4. Previously healthy patients do not usually need transfusion
even with losing 30–40% of their total blood volume and
volume loss should be replaced by crystalloids and colloids
RBC transfusion.
5. Transfusion decision should be made on peripheral tissue
oxygenation, clinical signs and symptoms, Hb and extent
and rate of bleeding.
Transfusion guidelines from American Society of Anaesthesio-
logists (ASA)16
In perioperative setting RBC transfusion is usually indicated
as shown below.
1. In otherwise healthy individuals if Hb <6 g/dL.
2. Rarely indicated with Hb >10 g/dL.
3. In patients with Hb 6–10 g/dL with evidence of organ
ischemia, rate and amount of bleeding, intravascular volume
status and risk factors for inadequate oxygenation (e.g. low
cardiopulmonary reserve) should be considered.
Transfusion guidelines from Society of Thoracic Surgeons and
Society of Cardiovascular Anaesthesiologists (STS/SCA)17
In general cardiology surgery patients, RBC transfusions are
considered:
1. To be reasonable if Hb <6 g/dL.
2. To be reasonable in most postoperative patients if Hb <7 g/dL.
3. May not be unreasonable in certain patients with Hb <10 g/dL
in the presence of critical ischemia in other organs (e.g.
central nervous system).
4. Rarely indicated if Hb >10 g/dL.
In patients undergoing cardiopulmonary bypass:
1. RBC transfusion is considered reasonable if Hb <6 g/dL.
2. May not be unreasonable to maintain Hb >7 g/dL in patients
with risk of critical end organ ischemia.
3. Patient related factors like age, severity of illness, cardiac
function, end organ ischemia, extent of blood loss, oxygen
saturation, evidence of myocardial ischemia and other
relevant parameters should be considered while decision
making on RBC transfusion.

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Transfusion guidelines from Society of Critical Care Medicine18
1. These guidelines are specifically for critically ill patients. RBC
transfusions usually indicated with Hb <7 g/dL for patients
requiring ventilation, critically ill trauma patients and
patients with stable cardiac disease.
2. With Hb <8 g/dL in acute coronary syndrome, RBC trans-
fusion may be beneficial.
3. Rarely indicated if Hb >10 g/dL.
4. Volume status, evidence of shock, duration/extent of anaemia
cardiopulmonary parameters are considered while decision
making on RBC transfusion.
Transfusion guidelines from the American Association of Blood
Banks19
These guidelines are for hospitalized haemodynamically stable
adult and children.
1. RBCs transfusions usually considered if Hb <7 g/dL for
critically ill patients and Hb of 8 g/dL or <8 g/dL for patients
undergoing surgery.
2. Hb levels and presence of symptoms are considered for
decision making on RBC transfusion.
Transfusion of Platelets
Indications of platelet transfusion are given below:
• In prophylaxis of haemorrhage: Platelet count of <10 × 109/L
coagulation disorders, petechiae, ecchymosis.
• Prior to surgical or invasive procedures, with platelet count
of <50 × 109 L.
• In case of microvascular bleeding without thrombocyto-
penia, when impairment of platelet function is confirmed
by laboratory tests. Platelets are transfused if this impairment
cannot be treated by other ways (e.g. in case of congenital
platelet disorders).
• Performing epidural anaesthesia or analgesia, with platelet
count of <100 × 109/L.
• In case of normal vaginal delivery, thrombocytopenia of
<50 × 109/L is safe without need for prophylactic platelet
transfusion.

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Blood Transfusion in Clinical Practice
• Platelets should not be transfused (except the cases of life-
threatening haemorrhage) under these circumstances: Auto-
immune thrombocytopenia, thrombotic thrombocytopenic
purpura, heparin-induced thrombocytopenia, post-trans-
fusion purpura.
Following are the AABB guidelines for platelet transfusion20
Recommendation 1: The AABB recommends that platelets
should be transfused prophylactically to reduce the risk for
spontaneous bleeding in hospitalized adult patients with
therapy induced hypoproliferative thrombocytopenia. The
AABB recommends transfusing hospitalized adult patients
with a platelet count of 10 × 109 cells/L or less to reduce the
risk for spontaneous bleeding. The AABB recommends trans-
fusing up to a single apheresis unit or equivalent. Greater doses
are not more effective, and lower doses equal to one half of a
standard apheresis unit are equally effective. (Grade: Strong
recommendation; moderate-quality evidence)
Recommendation 2: The AABB suggests prophylactic platelet
transfusion for patients having elective central venous catheter
placement with a platelet count less than 20 × 109 cells/L.
(Grade: Weak recommendation; low-quality evidence).
Recommendation 3: The AABB suggests prophylactic platelet
transfusion for patients having elective diagnostic lumbar
puncture with a platelet count less than 50 × 109 cells/L.
(Grade: Weak recommendation; very low-quality evidence).
Recommendation 4: The AABB suggests prophylactic platelet
transfusion for patients having major elective non-neuraxial
surgery with a platelet count less than 50 × 109 cells/L. (Grade:
Weak recommendation; very low-quality evidence).
Recommendation 5: The AABB recommends against routine
prophylactic platelet transfusion for patients who are non-
thrombocytopenic and have cardiac surgery with cardiopulmo-
nary bypass. The AABB suggests platelet transfusion for
patients having bypass who exhibit perioperative bleeding with
thrombocytopenia and/or evidence of platelet dysfunction.
(Grade: Weak recommendation; very low-quality evidence).

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Recommendation 6: The AABB cannot recommend for or
against platelet transfusion for patients receiving antiplatelet
therapy who have intracranial haemorrhage (traumatic or
spontaneous). (Grade: Uncertain recommendation; very-low-
quality evidence).
An usual dose of platelets is 1 unit/10 kg or 1 therapeutic
dose (consisting of 4–6 units of RDP), or 1 pack of apheresed
platelets (SDP).
One unit of platelet concentrate (RDP) has on average
5.5–7.5 × 1010 of platelets.
Conventionally 5–10 × 109 of platelet increment per RDP is
accepted after one hour of transfusion.
One unit of apheresed platelets has approximately 3.5–4 × 1011
platelets and increases recipient’s platelet count for 30–40 ×
109/L.
Transfused platelets should raise the platelet count of
recipients who have not been immunized or factors that reduce
platelet survival.
The formula for calculating the corrected count increment is:
2
11
Observed increment per µl
Body surface area (m )
Number of platelets given (10 )
×
Calculation of body surface area: Mosteller’s formula
×
Ht in cm
Weight in kg
3600
After platelet transfusion, the therapeutic effect is evaluated
after 60 minutes (1 hr), and again at 20–24 hours. Clinical studies
have showed that the best time to evaluate the effectiveness of
platelet transfusion is after 1 hour.
Failure to see the expected increment of platelets is mainly
because of anti-platelet antibodies or splenomegaly (1 hour CCI
reduced) or else due to decreased survival of the platelets as in
sepsis, infections, DIC (24 hours CCI reduced).
From CCI, effective dose (ED) of platelets can be calculated.
ED = Desired platelet increment
Body surface area
Expected CCI
×

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Post-platelet recovery (PPR): This is the percentage of platelets
(platelet increment) circulating in the blood after platelet trans-
fusion. Usually 2/3rd of the platelets remain in circulation, if
no splenomegaly or any other pathology of platelets exist. PPR
of less than 20% suggests platelet refractoriness.
This is calculated by the following formula:
11
Platelet increment per µl
Estimated blood volume
100
Number of platelet transfused (10 )
×
×
Transfusion of Fresh Frozen Plasma (FFP)
• Fresh frozen plasma is transfused, if in case of haemorrhage,
the prothrombin time or activated partial thromboplastin
time is prolonged for 1.5 times. If there is no haemorrhage,
FFP should not be used for correction of hypovolemia or
normalizing coagulation parameters. A recommended initial
dose of FFP is 10–15 mL/kg (average 3–4 units for a 70 kg
adult patient); however, some repeated doses might be
needed later on, after evaluation of therapeutic effect on
bleeding.
• FFP can be stored for a year at –20°C. FFP must be ABO
compatible with the recipient’s red blood cells.
• FFP has been used as an exogenous source of proteins,
especially albumin, immunoglobulins, coagulation factors
and certain protease inhibitors.
Indications
• Coagulopathy and bleeding of different origin.
• Bleeding in case of disseminated intravascular coagulation
(DIC).
• Thrombotic thrombocytopenic purpura.
• Congenital or acquired deficiency of different coagulation
factors, when there is no possibility to get a certain factor
concentrates (e.g. V or XI).
• Deficiency of specific plasma proteins (e.g. antithrombin III).
• Bleeding due to warfarin therapy.
• FFP should not be used when a coagulopathy can be
corrected with vitamin K.

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Transfusion of Cryoprecipitate
Indications
• Factor VIII deficiency.
• Haemorrhage due to hypofibrinogenemia or dysfibrinoge-
nemia.
• DIC syndrome.
• von Willebrand’s disease.
• Haemorrhage due to factor XIII deficiency.
Treating hypofibrinogenemia and transfusing cryoprecipitate
of 1–2 units/10 kg increases plasma fibrinogen concentration
for approximately 500 mg/L. Fibrinogen in plasma of 1 g/L is
sufficient to maintain hemostasis.
Therapeutic Plasmapheresis or Plasma Exchange (TPE)
TPE is defined as removal of pathological plasma component
and replacement of lost plasma with normal plasma, crystalloids
and colloids. Generally exchange is limited to 40 mL/kg body
weight (for 40 kg person 1600 mL) and lost plasma is replaced
by crystalloids and colloids. Indications of TPE is given below.
Indications for Plasmapheresis
Goodpasture’s syndrome
Myasthenia gravis crisis
(anti-GBM disease)
Thrombotic thrombocytopenic
Chronic inflammatory demyelinating
purpura
polyneuropathy
Hemolytic uremic syndrome
Eaton-Lambert myasthenic syndrome
Cryoglobulinemia
Post-transfusion purpura
Hyperviscosity syndrome
Refsum’s disease
Myeloma cast nephropathy
Cutaneous lymphoma (photopheresis)
Acute demyelinating polyneuro-
HIV-related syndromes (polyneuro-
pathy (Guillain-Barré)
pathy, hyperviscosity, TTP)
Homozygous familial hyper-
Bullous pemphigoid
cholesterolemia
Rapidly progressive glomerulo-
Pemphigus vulgaris
nephritis (without anti-GBM)
Paraproteinemic peripheral
Immune thrombocytopenia
neuropathy
Systemic vasculitis associated
Hemolytic disease of the newborn
with ANCA
ABO-incompatible marrow
Bullous pemphigoid
transplant
SLE (particularly in SLE cerebritis)

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Blood and Blood Component Transfusion in Obstetrics
• The blood volume is markedly raised in pregnancy due to
the increased vascularity of the enlarging uterus with
interposition of the utero-placental circulation. The rise is
progressive and consistent. All the constituents are affected
with increased blood volume. The blood volume starts
increasing from the 6th week, expands rapidly thereafter
to maximum 40–50% above the non-pregnant level at
30–32 weeks. The level remains almost static till term.
• Plasma volume: During pregnancy the plasma volume is
increased to the extent of 30–40%. Total plasma volume
increases to the extent of 1.25 litres. This increase is greater
in multigravida, multiple pregnancies and with large baby.
• The red cell volume is increased to the extent of 20–30%.
The total increase in red cell volume is 350 mL. The
reticulocyte count increases by 2%. Erythropoietin level is
raised.
• There is disproportionate increase in plasma volume as
compared to RBC volume which produces a state of hemo-
dilution during pregnancy.
TABLE 14.1: To show principle blood changes during pregnancy
Non-pregnant Pregnancy
Total
% increase
near term
increase
Blood volume (mL)
4000 mL
5500 mL
1500 mL 30–40
Plasma volume (mL)
2500 mL
3750 mL
1250 mL 40–50
Red cell volume
1400 mL
1750 mL
350 mL
20–30
Haemoglobin (gm %)
Haematocrit
38%
32%
18–20
• One woman dies from obstetric haemorrhage every minute.
The blood transfusions in pregnancy should be considered
in the following instances:
• Acute blood loss of any amount with clinical evidence of
inadequate oxygen carrying capacity or unstable vital signs.
• Symptomatic anaemia regardless of haemoglobin level even
if no bleeding.

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• Haemoglobin less than 7 gm, not amenable to other timely
therapies, antenatally, intrapartum or immediately post-
partum.
• Those receiving general anaesthesia, if the pre-operative
haemoglobin is below 7 gm/dL.
• Caesarean section with haemoglobin less than 10 gm%.
Antepartum haemorrhage: Placenta previa and abruptio
placenta are the two important causes of antepartum haemorr-
hage.
• Whenever the diagnosis of concealed variety of abruption
has been made clinically, at least one litre of blood trans-
fusion should be minimum to replenish the concealed blood
loss irrespective of patient’s general condition.
Peripartum/postpartum haemorrhage: Major obstetric haemorr-
hage can be peripartum and postpartum period. At term the
blood flow to placenta is approximately 700 mL/minute. The
patient’s entire blood volume can be lost in 5–10 minutes.
Unless the myometrium contracts on the placental site, blood
loss will continue, even after the third stage of labour is
complete.
• It is essential to monitor and investigate a patient with an
obstetric haemorrhage, even in the absence of shock.
• Blood transfusion helps by preventing ischemic renal
damage by maintaining blood pressure, prevents blood
coagulation disorders and ensures patient to be in better
form to withstand postpartum haemorrhage (PPH).
• Best indication to adequate blood replenishment rests on use
of CVP which should be maintained at about 10 mm of H2O.
• To maintain adequate organ perfusion, it is important to keep
a haematocrit of 30%, urinary output of at least 30 mL/hr
with IV fluids and blood.
Estimation of blood loss: Visual inspection is notoriously
inaccurate. In obstetrics, part or all the haemorrhage may be
concealed. It is important to realize that in a situation of acute
blood loss the immediate haematocrit may not reflect actual
blood loss. After the loss of 1000 mL, the haematocrit typically

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Blood Transfusion in Clinical Practice
falls only 3 volume percent in the first hour. During the
episode of acute significant haemorrhage, the initial haemato-
crit is always the highest.
ABO and Rh group with red cell antibody screening has to
be carried out for a pregnant woman during her first visit to a
doctor and at the 28th week of gestation. Another type of blood
testing is cross-matching. It is performed to determine the
compatibility of the donated blood with its intended recipient.
Crossmatching of blood should be requested under the
following circumstances:
• Major antepartum, intrapartum and postpartum haemorr-
hage
• Placenta previa
• Severe pre-eclampsia or eclampsia
• Significant coagulation disorders
• Anaemia (when Hb <10 g/dL) prior to cesarean section
• Before an operation, when there are some significant
obstetric abnormalities (uterine fibroids, previous classical
caesarean section, previous placenta accreta)
Some of principles to be observed are as follows:
• For emergency cases, obstetric units should always reserve
group ‘O’ Rh D negative, Kell-negative blood.
• In the absence of acute blood loss, ante-natal and post-natal
patients should only be transfused when reduction of haemo-
globin is associated with significant symptoms of anaemia.
Blood components used for transfusion in women of
reproductive age must be Kell-negative in order to avoid
alloimmunisation and subsequent haemolytic disease of the
newborn (unless it is known that a woman is Kell-positive).
• If anti-K antibodies are found during pregnancy, they most
likely have appeared due to previous transfusion, so this
should be kept in mind concerning future red cell trans-
fusions.
• It is recommended to use CMV-seronegative or leuco-depleted
blood components (since it is thought that using leucocyte
filters significantly reduces the risk of transmitting CMV).

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However, in emergency circumstances, the transfusion should
not be delayed if there are no CMV-seronegative blood
components available.
Some precautionary measures by the treating obstetrician
during pregnancy and delivery:
1. Clinician to care to maximize Hb at delivery
2. To minimize blood loss
3. Appropriate use of blood
4. Women with high risk pregnancy, to deliver at hospital with
all facilities and intensive care
5. Use of tranexamic acid
6. Use of recombinant VIIa factor
7. Check-up at 28 weeks of pregnancy
8. If placenta previa keep 2 units of blood ready
9. Every week crossmatch and keep the units reserved.
RCOG Guidelines in Obstetrics21
1. If Hb level is less than 10.5 gm/dL in antenatal period,
consider hematenic deficiency, once haemoglobinopathies
have been excluded. Oral iron should be preferred first line
of treatment for iron deficiency. Parenteral iron is indicated
when oral iron is not tolerated, absorbed or patient com-
pliance is in doubt. For parenteral therapy iron sucrose is
given in multiple doses, whereas iron dextran may be given
as single total dose infusion.
Anaemia not due to iron deficiency should be managed by the
blood transfusionist in close conjunction with haematologist.
Transfusion almost always indicated when Hb is less than
6 gm/dL.
2. In pregnancy, pre-autologous deposit is not recommended.
3. Blood counts and coagulation screen are performed before
giving FFP, cryoprecipitate and platelets.
4. Platelets should not fall below 50 × 109 in acute bleeding.
Neonatal Transfusion
• The total blood volume of neonates is small, although the
volume is higher per kg of body weight than that of older

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Blood Transfusion in Clinical Practice
children or adults (85 mL/kg for full-term and 100 to
105 mL/kg for pre-term).
• In neonates, a dose of 15 mL/kg of packed red blood cells
will increase the haemoglobin by approximately 3 g/dL and
5 mL/kg of packed red blood cells will increase Hb by 1 gm%.
• Avoid using blood donated by blood relatives to transfuse
neonates.
• Blood transfusion in pre-term infants is often given for the
anaemia of prematurity (associated with delayed renal
production of erythropoietin due to decreased sensitivity to
lower haematocrit levels). This commonly develops in
neonates after 2 weeks of life. Neonates, especially pre-term,
may require multiple transfusions.
• Blood component therapy is a very common intervention
practiced in newborns; nearly 85% of extremely low birth
weight (ELBW) babies get transfusions during their hospital
stay.
• Indications of packed red blood cells (PRBCs) for trans-
fusion in neonatal practice: PRBCs are the most commonly
used blood product in neonatal transfusions. Indications for
transfusion of PRBCs are mainly resolution of symptomatic
anaemia and for improvement of tissue oxygenation. Tissue
oxygenation depends on cardiac output, oxygen saturation
and haemoglobin concentration. Once cardiac output and
oxygen saturation are optimal, tissue oxygenation can only
be improved by increasing the haemoglobin level.
Canadian Paediatric Society recommends22 following guidelines for
red blood cell transfusion in newborns:
1. Group O Rh-negative blood may be used in the emergency
transfusion of newborns. Otherwise, either group O Rh-
compatible or group-specific Rh-compatible blood must be
used. Starting at four months postnatal age, crossmatching
of donor blood is required (strong recommendation).
2. In cases of massive haemorrhage, for which a large volume
of blood may be required, care should be taken to avoid
hyperkalemia and dilution of coagulation factors, using
combined replacement with fresh blood or frozen plasma,
as necessary (strong recommendation).

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Essentials of Blood Banking and Transfusion Medicine
3. ‘Top-up’ transfusions should be used to maintain haemo-
globin levels >7.5 gm/dL in convalescent preterm infants
(moderate recommendation).
4. For infants in the first and second week of life, minimum
haemoglobin levels of 10 gm/dL and 8.5 gm/dL, respectively,
are recommended (weak recommendation).
5. Infants needing respiratory support may require transfusion
at higher haemoglobin thresholds (weak recommendation).
6. Infants with cyanotic heart disease or similar haemodynamic
disorders may require transfusion at higher haemoglobin
thresholds (weak recommendation).
7. Transfusions should not be used to improve weight gain or
to address apnea of prematurity when haemoglobin levels
are already in excess of recommended levels for maintenance
(weak recommendation).
The guidelines for transfusion of PRBC vary according to
age, level of sickness and haematocrit.
TABLE 14.2: Guidelines for packed red blood cells (PRBCs) transfusion
thresholds for preterm neonates23
Less than 28
1. Assisted ventilation with FiO2 more than 0.3: Hb
days of age
12.0 gm/dL or PCV less than 40%
2. Assisted ventilation with FiO2 less than 0.3:
Hb 11.0 g/dL or PCV less than 35%
3. CPAP: Hb less than 10 gm/dL or PCV less than
30%
More than 28
1. Assisted ventilation: Hb less than 10 gm/dL
or days of age PCV less than 30%
2. CPAP: Hb less than 8 gm/dL or PCV less than
25%
Any age, breathing
1. On FiO2 more than 0.21: Hb less than 8 gm/dL
spontaneously
or PCV less than 25%
2. On room air: Hb less than 7 gm/dL or PCV
less than 20%
Red cells collected in CPDA-1 are kept as packed RBCs.
CPDA-1 packed RBCs have a haematocrit of approximately
75% and a shelf life of 35 days. An infusion of 10 mL/kg of
CPDA-1 packed RBCs would be expected to raise the patient’s
haematocrit by 9% to 10%.

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Blood Transfusion in Clinical Practice
CMV reduced RBCs are used to reduce the risk of trans-
mitting CMV, which may be a cause of considerable concern
in newborns. CMV reduction can be achieved by either leuko-
reduction of blood components, or by pre-selecting donors who
are CMV negative. Providing CMV reduced blood is important
in preterm infants, as preterm neonates can have severe form
of CMV infection than term newborns.
Practical issues
1. Amount of transfusion to be given: It has been seen that
transfusion with PRBCs at a dose of 20 mL/kg is well
tolerated and results in an overall decrease in number of
transfusions compared to transfusions done at 10 mL/ kg.
There is also a higher rise in haemoglobin with a higher dose
of PRBCs.
2. Properties of RBC products used in neonatal transfusion:
RBCs should be freshly prepared and should not be more
than 7 days old. This translates into a high 2, 3-DPG
concentration and higher tissue extraction of oxygen. Other
concerns with old RBCs are: Hyperkalemia, and a reduced
RBC life span. In small and sick neonates, where it is
anticipated that blood component therapy may be needed
more than once, it may help to have aliquots from a single
donor given as sequential transfusions. This is done practi-
cally by reserving a bag of fresh PRBCs for up to 7 days
for a newborn and withdrawing small aliquots required
repeatedly from that bag under laminar flow using a sterile
connecting device, into a fresh blood bag. The PRBC bag is
immediately resealed under the laminar flow, and can be
re-used for withdrawing similar small quantities of blood
for up to 7 days.
3. The infant’s Hb concentration at birth tends to be approxi-
mately 16.5 gm/dL and increases to 18.4 gm/dL within
24 hours at birth. During first 3 months of life all infants will
have a normal or physiological decrease in their Hb down
to approximately to 11.5 gm/dL. This decrease is greater in
pre-term infants. By 12 years of age, the Hb levels will be as
those of adults.24

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Essentials of Blood Banking and Transfusion Medicine
4. At birth until six months of age, the concentration of vitamin
K dependent coagulation factors (factors II, VII, IX and X)
and vitamin K dependent inhibitors of coagulation
(protein C and S) are lower than adult levels. By age of
6 months they will reach the levels approximately as that of
adults.24
Choosing the blood group for neonatal transfusion:
1. It is preferable to take samples from both, mother and the
newborn, for initial testing prior to transfusion. Mother’s
sample should be tested for blood group and for any
atypical red cell antibodies.
2. ABO compatibility is essential while transfusing PRBCs.
Though ABO antigens may be expressed only weakly on
neonatal erythrocytes, neonate’s serum may contain trans-
placentally acquired maternal IgG anti-A and/or anti-B.
3. Blood should be of newborn’s ABO and Rh group. It should
be compatible with ABO or red cell antibodies present in
the maternal serum.
4. In exchange transfusions for haemolytic disease of newborn,
blood transfused should be compatible with mother’s
serum. If the mother’s and the baby’s blood groups are the
same, use Rh negative blood of baby’s ABO group. In case
mother’s and baby’s blood group is not compatible, use
group O and Rh negative blood for exchange transfusion.
For exchange transfusion, red cells should be less than 5 days
old, sickle screen negative, collected in CPD anticoagulant
and gamma irradiated.
Volume and rate of transfusion:
a. Volume of packed RBCs = Blood volume (mL/kg) × (desired
minus actual haematocrit)/haematocrit of transfused
RBC.
b. Rate of infusion should be less than 10 mL/kg/hour in the
absence of cardiac failure.
c. Rate should not be more than 2 mL/kg/hour in the presence
of cardiac failure.
d. If more volume is to be transfused, it should be done in
smaller aliquots.

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Blood Transfusion in Clinical Practice
Expected response: Each transfusion of 9 mL/kg of body weight
should increase haemoglobin level by 3 g/dL. Meticulous
monitoring of input, output and vital signs are mandatory
during blood transfusion.
Neonatal Platelet Transfusion25–29
1. For a stable neonate <20,000 platelets/cmm
2. If unstable neonate <30,000 platelets/cmm
3. With active bleeding <50,000 platelets/cmm
Practical issues for platelet transfusion in neonates
1. Platelets should never be filtered through a micropore blood
filter before transfusion, as it will considerably decrease
the number of platelets.
2. Rh-negative infants should receive platelets from Rh-
negative donors to prevent Rh sensitization from the
contaminating red blood cells.
1. The usual recommended dose of platelets for neonates is
1 unit of platelet per 10 kg body weight, which amounts
to 5 mL/kg. The predicted rise in platelet count from a
5 mL/kg dose would be 20 to 60,000/cubic mm. Doses of
up to 10–20 mL/kg may be used in case of severe thrombo-
cytopenia.
2. Platelet count should not fall below 50,000/cmm in pre-
term neonates who exhibit active bleeding or at a great
risk of bleeding by an invasive procedure.25–29
3. In the selection of platelets units for transfusion, it is desir-
able that the infant and the platelet donor to be of the
same ABO blood group.
4. Repeated transfusions of O group platelets to A or B
recipients should be minimized in view of the anti-A and
anti-B antibodies causing lysis of the red cells.25–29
Following are to be kept in mind while transfusing the neonate:
• Infectious complications: In India, it is mandatory to test
every unit of blood collected for hepatitis B, hepatitis C,
HIV/AIDS, syphilis and malaria. However, transfusion
transmitted infections are still a considerable risk, because

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Essentials of Blood Banking and Transfusion Medicine
of the relative insensitivity of screening tests, and several
other organisms besides those tested for, which may be
transmitted through blood.
• Non-infectious complications: These can be immune
mediated and non-immune mediated reactions, or can
classified as acute and delayed complications.
• Immune mediated haemolysis: Acute haemolytic trans-
fusion reactions are common causes of transfusion related
fatality in adult patients, but these are rare in neonates.
Newborns do not have red blood cell (RBC) antibodies; all
antibodies present are maternal in origin.
• Newborns must be screened for maternal RBC antibodies,
including ABO antibodies if non-O blood group transfusion
to be given as the first transfusion.
• If the initial results are negative, no further testing is needed
for the initial few post-natal months. Infants are at a higher
risk of passive immune haemolysis from infusion of ABO
incompatible plasma present in PRBCs or platelet concen-
trates. Smaller quantities of ABO-incompatible plasma (less
than 5 mL/kg) are generally well tolerated. Newborns do
not manifest the usual symptoms of haemolysis that are
observed in older patients, such as fever, hypotension, and
flank pain. An acute haemolytic event may be present as
increased pallor, presence of plasma free haemoglobin,
haemoglobinuria, increased serum potassium levels, and
acidosis. Results of the direct antiglobulin (Coombs’) test
may confirm the presence of an antibody on the RBC surface.
Treatment is mainly supportive and involves maintenance
of blood pressure and kidney perfusion with intravenous
saline bolus of 10 to 20 mL/kg along with forced diuresis
with furosemide. Enforcing strict guidelines for patient
identification and issue of blood; and minimizing human error
is essential in preventing immune mediated haemolysis.
• Fluid overload: Neonates are at increased risk of fluid
overload from transfusion because the volume of the blood
component issued may exceed the volume that may be
transfused safely into neonates. Care should be taken to
ensure that, in the absence of blood loss, volumes infused

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Blood Transfusion in Clinical Practice
do not exceed 10 to 20 mL/kg. There is no role for routine
use of furosemide while transfusing newborns.
• Metabolic complications: These complications occur with
large volume of transfusions like exchange transfusions.
a. Hyperkalemia: In stored blood, potassium levels tend
to be high. It has been seen that after storage for around
42 days, potassium levels may reach 50 mEq/L in a RBC
unit. Though small volume transfusions do not have much
risk of metabolic disturbances, large volume transfusions
may lead to hyperkalemia. Washing PRBCs before
reconstituting with FFP before exchange transfusion
helps in preventing this complication.
b. Hypoglycemia: Blood stored in CPD blood has a high
content of glucose leading to a rebound rise in insulin
release, 1–2 hours after transfusion. This may lead to
hypoglycaemia and routine monitoring is necessary,
particularly after exchange transfusion, after 2 and 6 hours,
to ensure that this complication does not occur.
c. Acid–base derangements: Metabolism of citrate in CPD
leads to late metabolic alkalosis. Metabolic acidosis is an
immediate complication occurring in sick babies who
cannot metabolize citrate.
d. Hypocalcemia and hypomagnesemia: These are caused
by binding of these ions by citrate present in CPD blood.
• Transfusion associated graft-versus-host disease (TA-
GvHD): Newborns are at risk for TA-GvHD, if they have
received intrauterine transfusions or exchange transfusions.
Unchecked donor T cell proliferation is the cause of TA-GvHD,
and it can be effectively prevented by leuco-reduction and
irradiation of the transfused blood.
Blood and Blood Component Transfusion in Paediatric Patients
• Blood transfusions are life saving in modern intensive care
of premature neonates, children with cancer, children with
haemolytic anaemias, coagulation disorders and children
requiring transplants. The principles of transfusion in children
and adolescents are similar to those of adults, but infant has
special needs.

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146
Essentials of Blood Banking and Transfusion Medicine
• Transfusions are not without any risks and are to given only
when true benefits are likely.
• A clear indication of transfusion must exist; otherwise, the
child may be unnecessarily subjected to the risk of trans-
fusion associated problems.
• Components should not be unpacked until just before trans-
fusion. An informed consent from parents after explaining
the procedure and expected outcome must be taken. The
blood can be warmed in a water bath which is thermostati-
cally controlled, to ensure that the temperature of the water
bath does not exceed 42°C. Adjust flow rate as outlined and
never transfuse beyond 4 hours. Never inject any medication
into transfusion line.
Guidelines for Transfusion of RBCs in Full-term Infant under
4 Months of Age25–29
Hb less than 7 gm/dL with low reticulocyte count and with
symptoms of anaemia Hb less than 10 gm/dL in an infant:
• On <35% hood O2
• On O2 by nasal canula
• On ventilation with mean airway pressure of <6 cm of H2O
• With significant tachycardia and tachypnea
• With significant apnea and bradycardia
Hb less than 12 gm/dL in an infant:
• On >35% hood O2
• On continuous ventilation with mean airway pressure of
6–8 cm of H2O
Hb of 15 gm/dL in an infant:
• On ECMO
• With congenital cyanotic heart disease
For more than 4 months of age25–29
1. Acute blood loss more than 15% of total blood volume
2. Hb less than 7 gm/dL with symptomatic anaemia
3. Significant pre-operative anaemia when corrective therapy
is not available
4. Hb less than 13 gm/dL on ECMO

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Blood Transfusion in Clinical Practice
5. Chronic transfusion programs for disorders of RBC produc-
tion.
Guidelines for Platelet Transfusion in Children
1. 5–10,000 platelets/cmm with failure of platelet produc-
tion.
2. <30,000 platelets/cmm in a neonate with failure of platelet
production.
3. <50,000 platelets/cmm in premature neonate with active
bleeding and in cases of invasive procedures.
4. <1,00,000 platelets/cmm in a sick premature with active
bleeding and invasive procedures.