22. Pregnancy Flashcards
Describe the cardiovascular physiologic changes during pregnancy
- Decrease in systemic vascular resistance
- Increase in cardiac output
- Increase in HR
- Increased cardiac workload can result in ventricular hypertrophy
- Benign systolic ejection murmur is common (increased HR and blood volume; resolves after delivery)
- Uterine compression of inferior vena cava, leading to venous stasis and DVT
- Decrease in oncotic pressure leads to pedal edema.
Describe the hematological physiologic changes during pregnancy
- Increase in plasma exceeds that of erythrocytes, leading to physiologic anemia aka “hemodilution”
- Hypercoagulable state increases risk for DVT and pulmonary embolism
(reduction in protein S activity, activated protein C resistance, increase in coagulation factors except XI and XIII, pressure from gravid uterus causes endothelial damage, leukocytosis due to hormonal changes, suppression of immune system, decreased chemotaxis and cell-mediated immunity).
Describe the respiratory physiologic changes during pregnancy
- Relaxation of rib cage allowing for more horizontal position and upward displacement of the diaphragm
- Respiratory changes can result in respiratory alkalosis due to increase in minute ventilation
- Increase in O2 consumption
- Rapid desaturation during apnea
Describe changes in the following during pregnancy:
- Tidal volume
- Respiratory rate
- Minute ventilation
- Expiratory reserve volume
- Residual volume
- Functional residual capacity
- Tidal volume increases
- Respiratory rate increases
- Minute ventilation increases
- Expiratory reserve volume decreases
- Residual volume decreases
- Functional residual capacity decreases
Describe the genitourinary physiologic changes in pregnancy
Increase in GFR
Increase in renal blood flow
Increase in creatinine clearance
Third trimester bladder capacity reduction due to pressure from enlarged uterus
Hydroureter found in 90% of pregnancies
See increased rate of UTI due to urinary stasis
Describe the gastrointestinal system physiologic changes in pregnancy
- Decrease in lower esophageal sphincter tone
- Increase in gastric emptying time
- Increase in gastric pressure, can cause pyrosis (gastroesophageal reflux) complaint in 70% of pregnancies.
- Increase in bile secretion
- Increase in gallstone formation
Describe the endocrine physiologic changes in pregnancy
- Insulin resistance (fasting glucose levels are lower due to glucose utilization by the fetus
- Hypoglycemia can result from insulin resistance and glucose utilization by the fetus, especially in times of fasting
- Estrogen increases thyroxine-binding protein, which increases total levels of T3 and T4 (circulating free T3 and T4 remain unchanged)
What are some oral manifestations in the pregnant patient?
- Chronic gingivitis
- 1-5% develop pyogenic granulomas
- Decrease in salivary pH = decreased mucosal desquamation and dental decay
- Melanosis of the skin and mucosa due to increase in estrogen and progesterone
What is preeclampsia?
Preeclampsia is a pregnancy-induced condition due to abnormal placental implantation resulting in hypertension that occurs after 20 weeks of gestation or postpartum, accompanied by either proteinuria or other maternal organ dysfunction
What is the treatment of preeclampsia?
Term: delivery of fetus
Pre-term: conservative management with control of BP, fluid management, frequent observation, bed rest, delivery at 37 weeks
- if severe - delivery of fetus regardless and management of sequelae, antihypertensive therapies aimed at prevention of abruptio placentae and stroke (labetalol, hydralazine, nifedipine, seizure prophylaxis (mag sulfate).
What is Eclampsia?
Form of severe preeclampsia characterized by seizures or coma without any other brain pathology. Can be associated with respiratory failure, kidney failure, coagulopathy, stroke, cardiac arrest.
What is HELLP Syndrome?
Syndrome characterized by hemolysis, elevated liver transaminases, low platelet counts
- Occurs in conjunction with eclampsia or preeclampsia
- Subcapsular hepatic hematoma can form which can rupture and lead to severe intraabdominal bleeding and DIC
- High maternal and perinatal morbidity/mortality rate
- Immediate delivery; if gestational age less than 33 weeks, and mother is stable, consider steroids to allow for fetal maturation and improve platelet count. Delivery within 48 hours if maternal condition stabilized after steroid admin.
Gestational hypertension
Elevated blood pressure during pregnancy not associated with proteinuria or any preexisting chronic hypertension. SBP >140mm Hg and DBP >90 mm Hg.
- May develop into preeclampsia if proteinuria develops.
- May develop into chronic hypertension if it remains 3 months after delivery
What is gestational diabetes?
Any degree of glucose intolerance first recognized during pregnancy, diagnosed on a glucose tolerance test.
What are the medication categories as it relates to pregnancy?
Category A: controlled studies have failed to demonstrate a risk to the fetus
Category B: animal studies have not indicated fetal risk, and human studies have not been conducted, OR animal studies have shown a risk, but controlled human studies have not.
Category C: animal studies have shown a risk, but controlled human studies have not been conducted, or studies not available in humans or animals. Only give if potential benefit justifies risk to fetus.
Category D: positive evidence of human fetal risk exists, but in certain situations, the drug may be used despite risk.
Category X: evidence of fetal abnormalities and fetal risk exists based on human experience and the risk outweighs any possible benefit of use during pregnancy.
