Maternal Physio - Hema and Immuno Flashcards
Pregnancy is a state of ____ [hypo/hypervolemia]
Hypervolemia
Hypervolemia averages ___ percent above the nonpregnant blood volume after ___ weeks
- 40 to 45 percent
- 32 to 34
Note:
- This begins in the 1st trimester
- Most rapid increase on 2nd trimester
Summary:
- 12 weeks – 15%
- 32 weeks – 40 to 45%
When does increase in blood volume begin? When is it fastest?
- Begins in the 1st trimester
- Most rapid increase on 2nd trimester
The rationale of hypervolemia
- To meet the metabolic demands of the enlarged uterus with its greatly hypertrophied vascular system
- To provide an abundance of nutrients and elements to support the rapidly growing placenta and fetus
- To protect the mother and in turn the fetus, against the deleterious effects of impaired venous return in the supine and erect positions
- To safeguard the mother against the adverse effects of blood loss associated with parturition
In hypervolemia, what blood components increase?
Plasma and erythrocytes but proportionately more plasma
Reflects ↑ erythrocyte production
↑ Reticulocyte count
- Note:*
- As such, there is moderate erythroid hyperplasia in the bone marrow
What happens to hgb concentration and hct during pregnancy? What is mechanism?
They decrease; because of great plasma augmentation
Normal hemoglobin level during pregnancy
12.5 g/dL
Abnormal levels of hgb per trimester
- First
- < 10 g/dl
- Second
- < 10.5 g/dl
- Third
- < 11 g/dl
- Note:*
- Anemia in pregnancy is defined as hgb < 11 g/dl
Define anemia of pregnancy
Levels below 11.0 g/dL
When does physiologic anemia of pregnancy occur?
T2
- Note:*
- This makes sense as hypervolemia happens fastest during the second trimester
What change happens to whole blood viscosity?
Decreased
- Note:*
- Makes sense because although both RBC and plasma increases, plasma increases more so the hgb, hct and viscosity is decreased
Iron requirements in normal pregnancy is about how much? Describe the appropriation.
- 1000 mg/day
- 300 mg are actively transferred to the fetus and placenta
- 200 mg are lost (primarily in GIT)
- 500 mg due to increase in circulating erythrocytes
Summary:
- Most of the iron (50%) is used for hematopoiesis, especially in the last half of pregnancy
- 300 for the 3aby
Normal estimated blood loss in:
- Single NSD
- Twin NSD
- CS
- Single NSD
- 500 to 600 cc
- Twin NSD
- 1,000 cc
- CS
- 1,000 cc
T/F. Maternal blood volume ↑ more if having twins or higher order gestations as compared to singleton
True
Why is there a need for iron supplementation?
The amount of iron from the diet is insufficient to meet the needs of the pregnancy, so patients must take supplemental iron
Suppression of ____ is requisite for pregnancy continuation
Th1 response
Immunologic function during pregnancy (in general)
- Suppression of humoral and cell-mediated immunological functions
- Suppression of Th1 response is requisite for pregnancy continuation
Suppressed and upregulated immunologic activities
- Suppressed activity
- Decreased secretion of IL-2, interferon, and TNF-β due to Th1 and Tc1 suppression
- Upregulated activity
- ↑ secretion of IL-4, IL-6, IL-13 d/t Th2 upregulation
- IgA and IgG in cervical mucus
- IL-1B in cervical and vaginal mucus
Clinical implication of TH1 suppression in pregnancy
Results in remission of some autoimmune disorders such as RA, MS and Hashimoto thyroiditis
Failure of Th1 suppression may be related to development of ____
Pre-eclampsia
Normal leukocyte count during normal pregnancy and labor
- 5,000 to 12,000/μL (upper value up to 15,000/μL)
- During labor and early puerperium > 25,000/μL
If WBC is elevated 24 hours after delivery, entertain what possible diagnosis?
Endometriosis
Markers of inflammatory states, when and how
- ↑ CRP throughout pregnancy
- ↑ ESR d/t elevated plasma globulins and fibrinogen
- ↑ C3 and C4 during the 2nd and 3rd trimester
Coagulation and fibrinolysis factors that increase during pregnancy
- Fibrinogen
- Factor VII
- Factor X
- Plasminogen
Note:
- 1, 7, 10, plasminogen
- Oen, seven, ten, plasminogen
Hormone that causes an ↑ in clotting factors
Estrogen
Memory aid:
- Oen, seven, ten, plasgminogen
- Estroge
Coagulation and fibrinolysis factors that decrease during pregnancy
- aPTT
- tPA
- Antithrombin III
- Protein C
- Protein S
- Platelet
Memory aid:
- a_P_TT
- t_P_A
- Antithrombin III
- _P_rotein C
- _P_rotein S
- _P_latelet
What happens to the platelet level during pregnancy? What is the mechanism?
- Decreased (213,000/µL [non-pregnant 250,000])
- Mechanism
- Physiologic
- possibly due to hemodilution
- increased platelet consumption
- production of thromboxane A2, which induces platelet aggregation
- Physiologic
Platelet level returns to normal level when?
2 to 4 weeks postpartum
Thrombocytopenia platelet level
116,000/mL
