OB Flashcards
Describe the parturients blood gas levels:
pH - no change
PaO2 - increase - 104-108
PaCO2 - decrease - 28-32
Bicarb - decrease - 20
Describe O2 consumption in the parturient in the different stages of labor:
Term - increase 20%
First stage of labor - increase 40% over prelabor
Second stage of labor - increase 75% over prelabor
Describe CO of the parturient:
Increase 40% (10% goes to uterus)
HR increases 15%
SV increases 30%
Discuss CO during labor (as compared to pre-labor values)
1st stage: increases 20%
2nd stage: increases 50%
3rd stage: increases 80%
When does CO return to pre-labor values after birth?
24-48 hours
When does CO return to pre-pregnancy values?
About 2 weeks
How do twins affect CO?
Increase CO 20% above a single fetus pregnancy
Do MAP, SBP, or DBP change in the parturient?
MAP = no change (increased blood volume + decreased SVR = net even)
SBP = no change
DBP = decreased 15%
To which parturient should you apply left displacement of the uterus?
Anyone in the second or third trimester
How does intravascular fluid volume change in the parturient?
Increases 35% to prepare for hemorrhage in labor; creates dilution anemia
How do plasma volume and erythrocyte volume change in the parturient?
Plasma - increases 45%
Erythrocyte - increases 20%
What clotting factors increase in mom?
1, 7, 8, 9, 10, 12
What clotting factors decrease in mom?
11 and 13
What changes occur in antithrombin, protein s, and protein c?
antithrombin and protein s decrease. no change in protein c.
What changes occur in moms fibrinolytic system?
increased fibrin breakdown
Describe the parturients hematologic change overall?
Mom makes more clot, but she breaks it down faster.
How do PT and PTT change?
Decrease by 20%
Normal PT at term - 9.6-12.9s
Normal PTT at term - 24.7-35.0s
What occurs with platelet count?
Unchanged or decrease up to 10% due to hemodilution and consumption
How does MAC change in the parturient?
Decreases 30-40%
Does gastric volume increase or decrease in the parturient? Why?
Increases due to increased gastrin
How does gastric pH change in the parturient? Why?
Decreased due to increased gastrin
How does LES tone change in the parturient? Why?
Decreases due to increased progesterone and estrogen. Cephalad displacement also contributes.
Describe gastric emptying changes in the parturient:
No change before onset of labor; decreases after labor begins
What renal functions increase in the parturient and why?
GFR - increased blood volume and CO
Creatinine clearance - increase blood volume and CO
Glucose in urine - increased GFR and decreased renal absorption