From the Guidelines
Postpartum preeclampsia diagnosis requires immediate attention to prevent severe maternal morbidity and mortality, and key lab values to monitor include elevated blood pressure (≥140/90 mmHg), proteinuria (≥300 mg in 24-hour urine or protein/creatinine ratio ≥0.3), elevated liver enzymes (AST and ALT >2 times normal), decreased platelet count (<100,000/μL), elevated serum creatinine (>1.1 mg/dL), and increased LDH (>600 U/L) 1.
Key Lab Values to Monitor
- Elevated blood pressure (≥140/90 mmHg)
- Proteinuria (≥300 mg in 24-hour urine or protein/creatinine ratio ≥0.3)
- Elevated liver enzymes (AST and ALT >2 times normal)
- Decreased platelet count (<100,000/μL)
- Elevated serum creatinine (>1.1 mg/dL)
- Increased LDH (>600 U/L)
Treatment and Management
Treatment typically involves antihypertensive medications like labetalol (starting at 200-400 mg orally twice daily), nifedipine (10-20 mg orally every 4-6 hours), or hydralazine (5-10 mg IV every 20-40 minutes) to maintain blood pressure below 150/100 mmHg 1. Magnesium sulfate is administered for seizure prophylaxis (4-6 g IV loading dose followed by 1-2 g/hour maintenance) for at least 24 hours 1.
Postpartum Monitoring
Close monitoring is essential as postpartum preeclampsia can develop up to 6 weeks after delivery, even in women without previous hypertensive disorders during pregnancy 1. Regular postpartum follow-up should include:
- Blood pressure checks at least 4 to 6 hourly during the day for at least 3 days postpartum 1
- Symptom assessment, particularly for headaches, visual disturbances, epigastric pain, or shortness of breath
- Repeat laboratory tests, such as Hb, platelets, creatinine, and liver transaminases, the day after delivery and then second daily until stable if any of these were abnormal before delivery 1
From the Research
Postpartum Preeclampsia Lab Values
- The diagnosis of postpartum preeclampsia should be considered in women with new-onset hypertension 48 hours to 6 weeks after delivery 2.
- Lab values for postpartum preeclampsia may include:
- Severely elevated blood pressure
- Proteinuria (although the 0.3 g protein per gram of creatinine threshold may be non-specific postpartum due to physiologic proteinuria after delivery) 3
- Elevated uric acid
- Elevated liver function tests
- It is essential to note that postpartum preeclampsia may present without all the "classic" features, including elevated blood pressure, edema, proteinuria, and hyperreflexia 4.
- The cornerstones of treatment for postpartum preeclampsia include the use of antihypertensive agents, magnesium, and diuresis 2.
Diagnostic Challenges
- Physiologic proteinuria after delivery can make it challenging to diagnose postpartum preeclampsia using the urine protein to creatinine ratio (PC) 3.
- The reliability of PC is affected by mode of delivery, and utilizing the 0.3 threshold to diagnose preeclampsia in close proximity to delivery would contribute to increased false positive tests 3.
- A better understanding of the pathophysiology and specific risk factors for postpartum preeclampsia is imperative for patient care and counseling 2.