Fluid and blood in obstetric

1. FLUID AND BLOOD IN OBSTETRIC
Ahmed Al-Ghzali

2. OBJECTIVES:
• Simple review for fluid compartments in human body.
• Understand the physiologic effects of pregnancy on normal fluid dynamics.
• Identify on different types of fluid therapy and characteristics of each other in
treatment of critical cases.
• Identify the blood component and the role of each of them in blood transfusion.
• Take knowledge about complication of blood transfusion and try to reduce and
prevent this complication.
• Indication of blood transfusion in pregnancy.
• How to reduce and prevent of blood transfusion in pregnancy.

3. FLUID COMPARTMENT
• The total body water (TBW) ranges from 45% to 65% of total body weight in the human adult.
• TBW is distributed between two major compartments, the intracellular fluid (ICF) space and the
extracellular fluid (ECF) space. Two-thirds of the TBW resides in the ICF space and one-third in the
ECF space. The ECF is further subdivided into the interstitial and intravascular spaces in a ratio of 3:1
• Regulation of the ICF is mostly achieved by changes in water balance, whereas the changes in plasma
volume are related to the regulation of sodium balance.
• Because water can freely cross most cell membranes, the osmolalities within each compartment are
the same. When water is added into one compartment, it distributes evenly throughout the TBW.
• Infusions of fluids that are isotonic with plasma are distributed initially within the ECF; however, only
one-fourth of the infused volume remains in the intravascular space after 30 minutes.
• With intrapartum hemorrhage, ICF can be mobilized to restore the plasma volume.
• With hemorrhagic shock and mobilization of fluid from the ICF, the hematocrit, and thus oxygen-
carrying capacity, would be further reduced.

4. FLUID COMPARTMENT

5. THE PHYSIOLOGIC EFFECTS OF PREGNANCY ON NORMAL FLUID
DYNAMICS
• During pregnancy, the ECF accumulates 6–8L of extra fluid.
• Both plasma and red cell volumes increase during pregnancy. The plasma volume increases slowly but
to a greater extent than the increase in total blood volume during the first 30 weeks of pregnancy and
is then maintained at that level until term .
• the plasma volume increasing by 50% ,while Red cell mass increases about 24% during the course of
pregnancy.
• Plasma volume is increased by a greater fraction in multiple pregnancies .
• Reduced plasma volume expansion has been shown to occur in pregnancies complicated by fetal
growth restriction, hypertensive disorders, prematurity, oligohydramnios, and maternal smoking .
• Blood volume decreases over the first 24 hours postpartum, with non-pregnant levels reached at 6–9
weeks postpartum
• The glomerular filtration rate (GFR) increases during pregnancy, and peaks approximately 50% above
non-pregnant levels by 9–11 weeks gestation. This level is sustained until the 36th week.
• Sodium retention occurs throughout pregnancy due to multiple factors contribute in that, especially
because of Increased levels of aldosterone, deoxycortisone, progesterone, and plactental lactogen.

6. FLUID RESUSCITATION
• Crystalloid solutions
• Isotonic
• Hypertonic
• Hypotonic
• Colloid solutions
• Albumin
• Hetastarch
• Dextran
• And other

7. CRYSTALLOID SOLUTIONS:
• Isotonic crystalloid solutions are generally readily available, easily stored, non-toxic,
and reaction-free. They are an inexpensive form of volume resuscitation
• Equilibration within the extracellular space occurs within 20–30 minutes after
infusion. In healthy non-pregnant adults, approximately 25% of the volume infused
remains in the intravascular space after 1 hour. In the critically ill or injured patient,
however, only 20% or less of the infusion remains in the circulation after 1–2 hours
• Crystalloids either normal saline or Ringer’s lactate–are used to replenish plasma
volume deficits and replace fluid and electrolyte losses from the interstitium
• Given in a quantity of 3–4 times the amount of blood lost, they can adequately
replace an acute loss of up to 20% of the blood volume, although 3–5 L of
crystalloid may be required to replace a 1-L blood loss
Isotonic crystalloids:

10. COLLOID SOLUTIONS
Albumin:
• Albumin is produced in the liver and represents 50% of hepatic protein production
• It contributes to 70–80% of the serum COP . A 50% reduction in the serum albumin concentration
will lower the COP to one-third of normal.
• The normal serum albumin concentration is maintained between 3.5 and 5g/dL
• One gram of albumin increases the plasma volume by approximately 18 mL
• Albumin is available as a 5% or 25% solution in isotonic saline. Thus, 100 mL of 25% albumin solution
increases the intravascular volume by approximately 450 mL over 30–60 minutes
• 500-mL solution of 5% albumin containing 25 g of albumin will increase the intravascular space by
450 mL
• Infused albumin has an initial plasma half-life of 16 hours, The albumin equilibrates between the
intravascular and interstitial compartments over a 7–10-day period, with 75% of the albumin being
absent from the plasma in 2 days. In patients with shock, the administration of plasma albumin has
been shown to significantly increase the COP for at least 2 days after resuscitation
• In patients with acute blood loss of greater than 30% of blood volume, it probably should be used
early in conjunction with a crystalloid infusion to maintain peripheral perfusion. Treatment goals are
to maintain a serum albumin of greater than 2.5g/dL in the acute period of resuscitation

14. • The prevention is the best way
• Sodium restriction
• Fluid restriction
• Diuretics
• Bounding pulse
• Pulmonary crackles
• Peripheral edema
• Dyspnea
• Hypertension
• Jugular venous distension
Treatment of fluid overload
Percussions in usage of isotonic solutions
• Frequently assess the patient response
• Monitor intake and output
• Elevate the head of the bed at 35 to 45 degree unless there is contraindicated
• If edema is present elevate the patient legs

15. How to calculate the IV fluid rate
• In blood set….............. 10 drop in each ml
• In regular set…............15 drop in each ml
• In microdrip set…........60 drop in each ml
Equation:
Volume(ml) # drop rate(gtts/ml)
time(min)

16. Fluid maintenance
• Maintenance therapy usually undertaken in individual not expected to
eat or drink normally for a long time, e.g. perioperative patient or patient
on ventilator

17. How to estimate maintenance fluid therapy

18. Blood component

21. Blood collection and immediate storage
• A unit of blood should be collected with a minimum of trauma and over
a short time period (4–10 minutes) to decrease the likelihood of
activation of coagulation factors.
• Each collection bag usually contains an average of 450 (45mL) of whole
blood plus 63mL of anticoagulant/preservative.
• Two commonly used storage solutions are CPD (citrate-phosphate-
dextrose) and CP2D. The citrate chelates calcium, and prevents activation
of the calcium-dependent steps of the coagulation process. Dextrose
serves as a sub- strate for red cell glycolysis, while phosphate buffers
lactic acid produced by metabolism.
• The addition of adenine to the storage solution (e.g. in CPDA-1) to
support RBC synthesis of ATP allows the blood to be stored for 35 days
• Storage of collected blood at 1–6°C slows glycolysis.

22. Transfusion reaction

23. Complications of blood transfusion
• immunologic and hemolytic reactions
• volume overload: with the potential of pulmonary edema
• hypothermia
• coagulopathy
• citrate toxicity
• acute lung injury
• post-transfusion purpura

25. Blood transfusion in obstetric
Indications:
• Anemia of pregnancy & hemoglobinopathy
• Obstetric hemorrhage
• Surgery where expected blood loss
• If Hb <6 g/dl and there are <4 weeks for delivery
• If Hb <7 g/dl at labour or immediately postpartum
• If Hb <7 g/dl and at risk of continuous bleeding or at further bleading
The decision of blood transfusion should be not estimated on the
level of hemoglobin alone, as healthy and stable pregnant even
the level of her hemoglobin less than 7 g/dl not necessary for
blood transfusion

26. Anemia in pregnancy
Few point you should be remember:
• Anemia is the late manifestation of iron deficiency anemia
• Blood transfusion will not correct the cause
• The aim of Hb in first trimester is equal and above 11 g/dl , while in
second trimester should be equal and above 10.5 g/dl , and in
postpartum should be equal and above 10 g/dl
• Blood transfusion will not correct the non-hematological problems that
may happen due to anemia like:
• Impair neuromuscular function that may lead to increase blood loss at
delivery
• Abnormal cellular function that may lead to preterm labor
• Abnormal fetal growth
• Reduce the iron store in newborn and that lead to anemia for neonate

27. Anemia in pregnancy
Minimize the blood transfusion in obstetric:
• Optimization of the Hb level in antenatal care visit (good compliance
on antenatal care visit)
• Prophylactic treatment, where should be the pregnant supplementation
can be achieved with 30–60 mg of elemental iron daily, and folic acid
supplementation (400μg/day) is routinely given in the first trimester. It
should also be taken for 3 months prior to conception in those
planning pregnancy and a higher dose is needed if there is a previous
child with a neural tube defect or a chronic red cell disorder
• The treatment of established iron deficiency is with 200mg of elemental
iron daily

28. Minimize the blood transfusion in obstetric:
• Minimized blood loss at delivery
• Active management of the third stage of labour(clear evidence from
randomized trials)
• Women at high risk of hemorrhage should be advised to deliver at
hospital
• Optimal management of women on anticoagulants, such as low-
molecular-weight heparin, will minimize blood loss.

29. Hemoglobinopathy in pregnancy
Indications of blood transfusion for pregnancy with sickle cell
anemia:
• If haemoglobin < 5 g/dL
• If there is preeclampsia
• If there is septicemia
• If there is acute renal failure
• If there is acute chest syndrome
• If there is recent cerebral ischemia of arterial origin
• And when preparing for surgery
• Multiple pregnancy will require assessment on many regular basis

30. Obstetric hemorrhage
Postpartum hemorrhage (PPH):
• It is meaning loss more than 5oo ml of blood after vaginal delivery, or more than
1000 ml of Primary PPH that happen within the first 24 hour of postpartum, while
secondary PPH happen after 24 hour of postpartum and up to 12 week (some
reference say up to 6 week of postpartum)
• blood after cesarean surgery, or decrease in hematocrit more than 10% after
delivery from the baseline before delivery
Antepartum hemorrhage (APH):
• Placenta Previa
• Placenta abruption

32. thank you