Pregnancy and Coexisting Disease Flashcards
What is the primary goal of gestational diabetes management?
Replicate low maternal glucose levels (70-120 mg/dl)
What is the primary goal of gestational diabetes management?
Replicate low maternal glucose levels (70-120 mg/dl)
What are normal maternal glucose levels during pregnancy?
Fetus continuously draws from maternal supplies creating blood glucose of 70-120 mg/dl
What is the key gestational diabetes management concept to remember regarding glucose and insulin?
glucose crosses the placenta but insulin does not
Why do mothers with gestational diabetes tend to have larger babies?
- mother’s blood brings extra glucose to fetus
- fetus makes more insulin to handle the extra glucose
- extra glucose gets stored as fat and fetus becomes larger than normal
What are birth defects that can occur with gestational diabetes?
neural tube defects cardiac defects (most common)
When does a baby have macrosomnia from gestational diabetes?
> 4000 grams or 8.5 lbs
What are other complications that can occur during birth if the mother had gestational diabetes?
shoulder dystocia
brachial plexus injury
What are fetal complications of gestational diabetes?
- respiratory distress syndrome (lung maturity delayed)
- intrauterine fetal demise
- hyperbilirubinemia
- hypoglycemia post delivery (potential seizures, coma, brain damage)
- childhood and adolescent obesity
What are maternal complications of GDM?
- worsening of type I diabetes complications (retinopathy and nephropathy)
- increased incidence of miscarriage, HTN, pre-eclampsia, C-section
When does maternal screening for GDM occur?
What is the treatment for GDM?
- supplemental folic acid (decreases neural tube defects)
- tight glucose control (capillary glucose monitoring 4-7 times/day–esp in 3rd trimester)
- intensive fetal surveillance (serial ultrasounds for pregnancy dating, level 2 ultrasound for birth defects, fetal echocardiogram, amnio for fetal lung maturity for delivery
What do you do for glucose control in patient with GDM during labor and delivery?
- diet-controlled diabetics (GDMA1) –> no glucose containing IV fluids
- insulin-dependent diabetics (GDMA2) –> accu checks q1-2 hours with sliding scale coverage, combined glucose and insulin infusions during the intrapartum period (D5LR at 100 mL/hr and insulin gtt at 0.5-1 unit/hr)
What are the 4 types of HTN that can occur during pregnancy?
- gestational HTN (HTN>20 weeks without proteinuria)
- pre-eclampsia (HTN and proteinuria +/- edema >20 weeks)
- chronic HTN
- chronic HTN with superimposed pre-eclampsia
What are normal maternal glucose levels during pregnancy?
Fetus continuously draws from maternal supplies creating blood glucose of 70-120 mg/dl
What is the key gestational diabetes management concept to remember regarding glucose and insulin?
glucose crosses the placenta but insulin does not
Why do mothers with gestational diabetes tend to have larger babies?
- mother’s blood brings extra glucose to fetus
- fetus makes more insulin to handle the extra glucose
- extra glucose gets stored as fat and fetus becomes larger than normal
What are birth defects that can occur with gestational diabetes?
neural tube defects cardiac defects (most common)
When does a baby have macrosomnia from gestational diabetes?
> 4000 grams or 8.5 lbs
What are other complications that can occur during birth if the mother had gestational diabetes?
shoulder dystocia
brachial plexus injury
What are fetal complications of gestational diabetes?
- respiratory distress syndrome (lung maturity delayed)
- intrauterine fetal demise
- hyperbilirubinemia
- hypoglycemia post delivery (potential seizures, coma, brain damage)
- childhood and adolescent obesity
What is the one proposed theory explaining the cause of pre-eclampsia?
ulteroplacental ischemia causes production and release of biochemical mediators into the maternal circulation which then cause arteriolar constriction and vasospasm and vascular endothelial dysfunction
When does maternal screening for GDM occur?
What is the treatment for GDM?
- supplemental folic acid (decreases neural tube defects)
- tight glucose control (capillary glucose monitoring 4-7 times/day–esp in 3rd trimester)
- intensive fetal surveillance (serial ultrasounds for pregnancy dating, level 2 ultrasound for birth defects, fetal echocardiogram, amnio for fetal lung maturity for delivery
What do you do for glucose control in patient with GDM during labor and delivery?
- diet-controlled diabetics (GDMA1) –> no glucose containing IV fluids
- insulin-dependent diabetics (GDMA2) –> accu checks q1-2 hours with sliding scale coverage, combined glucose and insulin infusions during the intrapartum period (D5LR at 100 mL/hr and insulin gtt at 0.5-1 unit/hr)
What are the 4 types of HTN that can occur during pregnancy?
- gestational HTN (HTN>20 weeks without proteinuria)
- pre-eclampsia (HTN and proteinuria +/- edema >20 weeks)
- chronic HTN
- chronic HTN with superimposed pre-eclampsia
What are the 3 triad of symptoms you see with pre-eclampsia?
- labile HTN
- proteinuria
- non-dependent edema –> weight gain
When doe pre-eclampsia occur?
after the 20th week of pregnancy
What is eclampsia?
seizure activity in patient pre-eclampsia
What is the chance of a woman with pre-eclampsia progressing to eclampsia?
0.5-2%
What SBP and DBP define pre-eclampsia?
SBP >140 mmHg
DBP >90 mmHg
must be on 2 separate readings >6 hours apart
What amount of proteinuria defines pre-eclampsia?
> 300 mg protein/24 hours
>/= protein on dip stick (clean catch, no UTI)
What is the incidence of pre-eclampsia in different populations?
- primipaternity (1st child)
- extremes of age
- african-americans
- increased placental tissue (twins, moles)
- co-existing disease (DM, chronic HTN, renal disease)
What is the etiology of pre-ecampsia?
unknown, but multiple theories around, possibly related to decreased placental perfusion and uteroplacental ischemia (but not sure which one came first to cause the other)
What is the one proposed theory explaining the cause of pre-eclampsia?
ulteroplacental ischemia causes production and release of biochemical mediators into the maternal circulation which then cause arteriolar constriction and vasospasm and vascular endothelial dysfunction
What is the treatment for pre-eclampsia?
- delivery of fetus and placenta is definitive treatment
- medical management - control of HTN, anticonvulsant prophylaxis, maintenance of renal function, determination of fetal lung maturity
- strict bedrest
- left uterine displacement
- +/- low-dose aspirin treatment
- intrapartum - fluid restriction, isotonic IV solutions, pharmacotherapy to treat HTN and prevent/treat seizures
What are the 3 primary manifestations of pre-eclampsia?
HTN
hypercoagulability
increased vascular permeability (decreased intravascular volume, end organ hypoperfusion, edema, proteinuria)
What are the CV effects of pre-eclampsia?
- labile HTN
- vascular leakage of fluid and proteins due to dec. colloid osmotic pressure, dec. intravascular volume, and edema
- severe pre-eclampsia with SBP>/=160 or DBP>/=110
What are the pulmonary effects of pre-eclampsia?
- upper airway edema
- severe pre-eclampsia –> pulmonary edema
What are the hematologic effects of pre-eclampsia?
- hypercoagulability
- hemoconcentration
- severe pre-eclampsia –> thrombocytopenia (most common), DIC
What are the renal effects of pre-eclampsia?
- proteinuria
- low urine output
- decreased uric acid clearance
- severe pre-eclampsia –> oliguria and renal failure
What are hepatic effects of pre-eclampsia?
- impaired function
- elevated LFTs
- severe pre-eclampsia –> swelling of liver capsule causing epigastric pain, liver necrosis, subcapsular hematoma
What are the CNS effects of pre-eclampsia?
- HA
- hyperreflexia
What are the CNS effects in a patient with SEVERE pre-eclampsia?
visual disturbances cerebral edema eclamptic seizures cerebral hemorrhage maternal death
What are placental effects of pre-eclampsia?
- hypoperfusion
- severe pre-eclampsia –> infarct, abruption
What are the fetal effects of pre-eclampsia?
- IUGR
- prematurity
- severe pre-eclampsia –> hypoxemia, fetal distress, IUFD
What lab values would you want to check for someone with pre-eclampsia?
- Hgb/Hct
- platelet count
- 24 hour urine >/= 300 mg/dl protein
What lab values would you want to check for someone with SEVERE pre-eclampsia?
- BUN and Cr
- LDH, ALT, and AST
- uric acid
- PT (DIC)
What is the treatment for pre-eclampsia?
- delivery of fetus and placenta is definitive treatment
- medical management - control of HTN, anticonvulsant prophylaxis, maintenance of renal function, determination of fetal lung maturity
- strict bedrest
- left uterine displacement
- intrapartum - fluid restriction, isotonic IV solutions, pharmacotherapy to treat HTN and prevent/treat seizures
What are the drugs of choice to manage pre-eclampsia?
magnesium sulfate hydralazine labetalol May also include: phenytoin midazolam, diazepam nifedipine nitroprusside
What is the anticonvulsant of choice with pre-eclampsia?
magnesium sulfate, controls seizures in 95% of cases
What is the dose of magnesium sulfate?
4-6 grams loading dose over 20 minutes then maintenance infusion of 1-2 grams/hr
What other drugs can be given as anticonvulsant prophylaxis?
- phenytoin can be added in eclampsia
- diazepam/midazolam may be used to control seizures resistant to magnesium sulfate
What is the dose of phenytoin?
20 mg/kg IV at a rate of 12.5 mg/min, max dose of 1500 mg/day
What are the doses of midazolam/diazepam?
titrate to effect
How does magnesium sulfate work?
antagonizes calcium channels in the smooth muscle cells, vasodilates and increases uterine blood flow, decreases Ach release at the neuromuscular junction
What are therapeutic levels of MgSO4?
4-8 mEq/L, actual levels monitored only in renal impairment of symptomatic toxicity
What are adverse side effects of MgSO4?
- respiratory depression
- CNS depression
- cardiac conduction block at toxic levels
What are signs and symptoms of MgSO4 toxicity?
- respirations
What is the treatment for MgSO4 toxicity?
10-20 mL of 10% calcium gluconate IV (remember that it reverses beneficial effects of MgSO4)
What are some anesthetic implications with MgSO4?
- Can increase neuromuscular blockade with both depolarizers and nondepolarizers (decreases endplate senstivity to Ach motor end-plate release)
- Increases NMB with aminoglycoside abx
- May cause significant hypotension when used concurrently with antihypertensives
- decreased uterine tone
What is the goal DBP in treatment of HTN in pre-eclampsia?
DBP 90-100 mmHg
What is the antihypertensive of choice?
hydralazine - vasodilates arterioles and increases HR, increasing CO, and improves placental blood flow
What is the 2nd line of therapy for HTN with pre-eclampsia?
labetalol - vasodilates without increased HR, also improves placental blood flow
What is the dose of hydralazine?
5-10 mg IV q20 mins to maximum of 60 mg (remember delayed onset time of ~20 mins)
What is the dosing of labetalol?
step-wise IV dosing (20-40-80 mg) q10 mins to maximum of 300 mg
What is the dose of nifedipine?
10-40 mg PO TID
What is the dosing of nitroprusside?
0.2-10 mcg/kg/min IV, increased prn
What differentiates eclampsia from pre-eclampsia?
seizure activity
When can eclampsia occur?
up to 48 hours post partum
What is the maternal and fetal mortality rate from eclampsia?
maternal - 1%
fetal - 12%
When do majority of seizures with eclampsia occur?
prior to delivery (75%, 25% prior to onset of labor and 50% occur during labor)
What type of seizures are associated with eclampsia?
tonic-clonic, lasting 60-70 secs, followed by post-ictal phase
What is the treatment for eclampsia?
- clear/secure airway as indicated (don’t intubate unless become hypoxic)
- administer oxygen
- left uterine displacement
- initiate MgSO4 therapy
- C-section usually elected shortly after eclamptic seizure, though labor may be induced if cervix is favorable
What are some anesthetic implications for a c-section with an eclamptic patient?
- stabilize patient prior to c-section to prevent further renal impairment due to surgical stress
- may need swan-ganz catheter and a-line
- GETA usually done because thrombocytopenia/coagulopathy contraindicate regional anesthesia and airway is secured
What is HELLP syndrome?
defined as Hemolysis, Elevated Liver enzymes, and Low Platelet count
When can HELLP syndrome occur?
occurs in 10% of pre-eclamptics and 30-50% of eclamptics
How is the liver affected by HELLP?
hepatocellular necrosis and liver dysfunction occur which can cause DIC and hemorrhage
What is “vertical transmission” of HIV?
transmission from mother to infant
- 25% in untreated women
- 2% in treated women
What is the mean survival time of HIV infected infants?
10 years
When can vertical transmission occur?
- prenatally
- intrapartum (most common)
- breastfeeding
What are the 2 routes of transmission of HIV from mother to fetus?
- hematologically across the placenta
- across the amniotic membranes (especially if inflamed/infected)
How does intrapartum transmission occur?
neonatal contact with maternal blood and cervicovaginal secretions, transmission rate increases with time and amount of neonatal exposure
How can postnatal transmission of HIV be prevented?
no breastfeeding
What is the treatment of HIV during pregnancy?
prenatal, perinatal, and fetal postnatal antiviral therapy along with elective c-section, lowers vertical transmission rate as low as 2%
What are the CDC guidelines for prenatal antiviral treatment?
Zidovudine (AZT, ZDV, Retrovir) 300 mg PO bid
What are the CDC guidelines for perinatal antivital treatment?
continuous IV zidovudine infusion at 1 mg/kg/hr, discontinue with cord clamping
What are the CDC guidelines for postnatal antivital treatment?
Zidovudine within the first 6-12 hours of life until 6 weeks old, may be discontinued at 6 weeks if HIV tests are negative
When should rupture of the membranes (ROM) occur with HIV mom?
after elective c-section
What is the most common coexisting medical condition affecting reproductive-aged women?
asthma
What is the course of asthma during pregnancy?
1/3 improve
1/3 remain normal
1/3 become worse
- pregnancy can have any effect on asthma
Which gestational weeks tend to be most difficult for asthmatics?
24-36 because of displacement of the diaphragm and reduced FRC
When does asthma severity return to baseline?
3 months post-partum
What is the treatment of asthma during pregnancy?
- control and avoidance of triggers (allergens, irritants, GERD, UTIs, exercise)
- pharmacotherapy (uncontrolled asthma poses greater risk to fetus than medications during pregnancy)
What is the outpatient asthma pharmacotherapy regimen?
- inhaled corticosteroids
- beta 2 agonists as rescue med.
- theophylline (3rd line treatment)
- leukotriene receptor antagonists/synthesis inhibitors (singulair, accolate, zyflo), role in pregnancy unclear
What is the treatment of acute asthma exacerbation?
- oxygen (should be used liberally, maintain O2 sats >95%)
- systemic corticosteroid course
- beta 2 agonists (administered via nebulizer or MDI with spacer, ipatropium may be added)
- theophylline (limited use in acute exacerbations)