Definitions
BP >140/90 on at least 2 occasions, 4 hours apart with normal laboratory findings, patient asymptomatic
Gestational hypertension
Threshold for treatment in pregnancy
140/90
Medication used for prophylaxis
81mg aspirin
Delivery timing for preeclampsia without severe features or gestational hypertension
37 weeks
Duration for magnesium treatment
delivery > 24 hours postpartum
Hypertension present before pregnancy or diagnosed before 20 weeks gestation
Chronic hypertension
Labetalol
Nifedipine
When to start prophylaxis
12 to 28 weeks (continued through delivery)
Delivery timing for preeclampsia with severe features
Typical IV dosages
6mg bolus, then 2mg/hr
BP >140/90 on at least two occasions greater than 4 hours apart with proteinuria, no other laboratory abnormalities, patient asymptomatic
Preeclampsia without severe features
Diagnosis: New-onset proteinuria, new and persistent severe range BP, LFT >2x normal, thrombocytopenia
Chronic hypertension with superimposed preeclampsia with severe features
Three risk factors for hypertensive disorders of pregnancy
Nulliparity, multiple gestation, history of preeclampsia, obesity, chronic hypertension, pregestational and gestational diabetes, advanced maternal age, obstructive sleep apnea, thrombophilia, SLE, anti-phospholipid syndrome, kidney disease, assisted reproductive technology
When to recommend magnesium prophylaxis?
Chronic hypertension with superimposed preeclampsia with severe features
Preeclampsia with severe features
HELLP
Eclampsia
Dosage and route if no IV access
IM injection of 5mg in each buttock, total 10mg as "bolus"
then 5mg every 4 hours
BP >140/90 on at least two occasions more than 4 hours apart with proteinuria AND BP >160/110 requiring treatment with antihypertensives, symptoms (persistent headache, vision changes, shortness of breath, chest pain, RUQ pain, nausea/vomiting, acute edema) not attributed to alternative cause, or laboratory abnormalities (eg LFTs >2x upper limit of normal)
Preeclampsia with severe features
Delivery timing when controlled on medications
37 to 39 weeks gestation
Definition of proteinuria
Urine protein to creatinine ratio > 0.3
24 hour urine protein >300
Dipstick 2+ (in settings without access to above methods)
Persistent severe range >160/110, 15 minutes apart
Therapeutic range
4.8-9.6 mg/dL
New onset seizure during pregnancy or postpartum not related to other cerebral condition
Eclampsia
Delivery timing when severe range BP or concern for superimposed preeclampsia with severe features
34 weeks or at time of diagnosis
Definition of HELLP
Hemolysis: Abnormal peripheral blood smear (schistocytes, burr cells, echinocytes), Increased bilirubin >1.2, Increased LDH >600 IU/L
Elevated LFTs Increased AST/ALT to >2x upper limit of normal
Platelet count < 100,000/mm3
IV antihypertensive regimens
IV labetalol 20 > 40 > 80
IV hydralazine 5 > 10
PO Nifedipine IR 10-20mg
First sign of magnesium toxicity and reversal method
Loss of deep tendon reflexes
Calcium gluconate 10% solution