What is the best intrapartum surveillance for a hypertensive patient with a low-risk and uncomplicated pregnancy to ensure maternal and fetal well-being during labor?

Best Intrapartum Surveillance for Hypertensive Patient in Labor

For a hypertensive patient presenting for labor, even if otherwise low-risk, the best intrapartum surveillance is continuous electronic fetal heart rate monitoring combined with frequent maternal blood pressure assessment—not intermittent monitoring—because hypertension places this pregnancy at increased risk for acute complications including superimposed preeclampsia, placental insufficiency, and hypertensive crises during labor. 1

Why This Patient is NOT Low-Risk

Despite being described as "low-risk and uncomplicated," the presence of hypertension fundamentally changes risk stratification:

• At least 25% of gestational hypertension cases progress to preeclampsia, and this progression can occur rapidly during labor 2, 1
• Controlled hypertension on medication places patients at risk for superimposed preeclampsia, placental insufficiency, and acute hypertensive crises during labor 1
• Blood pressure alone is not a reliable indicator of disease severity; serious organ dysfunction can develop at relatively mild levels of hypertension 1

Required Maternal Monitoring Components

Blood Pressure Surveillance

• Continuous or very frequent blood pressure monitoring throughout labor is essential, with target BP maintained at 110-140/85 mmHg 2, 1
• Blood pressure ≥160/110 mmHg lasting >15 minutes constitutes a hypertensive emergency requiring immediate treatment within minutes 2, 1
• Urgent treatment options include oral nifedipine or intravenous labetalol/hydralazine 2

Clinical Assessment for Preeclampsia Progression

• Monitor for emergency symptoms: headache, visual disturbances, epigastric pain, neurological symptoms 2, 1
• Assess for signs of impending eclampsia: brisk reflexes, persistent severe symptoms 2
• Monitor for oliguria (<35 mL/h for 2 hours) as an early maternal warning sign 2, 1

Laboratory Surveillance

• Baseline and serial monitoring should include: complete blood count (hemoglobin, platelet count), liver transaminases, serum creatinine, uric acid, and urinalysis for proteinuria 2, 1
• These tests detect potential complications such as HELLP syndrome and renal dysfunction 1

Required Fetal Monitoring

Continuous Electronic Fetal Monitoring is Indicated

• Continuous intrapartum electronic fetal monitoring is recommended for pregnancies with increased risk of perinatal death or neonatal encephalopathy 3
• Hypertensive disorders create risk for placental insufficiency and acute fetal decompensation during labor 1
• Electronic fetal monitoring records should be inspected and documented every 15 minutes in active labor and at least every 5 minutes in second stage 2, 3

Interventions for Abnormal Tracings

If fetal heart rate tracing becomes abnormal, implement the following sequence:

• Change maternal position 2
• Assess maternal vital signs (temperature, blood pressure, pulse) 2
• Discontinue oxytocin if in use 2
• Initiate oxygen at 6-10 L per minute 2
• Perform vaginal examination (check for cord prolapse, rapid descent, or bleeding) 2
• Give intravenous fluid bolus if not already administered 2
• Consider fetal scalp stimulation to assess fetal pH 2

Critical Management Thresholds

When to Administer Magnesium Sulfate

• Magnesium sulfate for seizure prophylaxis must be administered if severe hypertension (≥160/110 mmHg) develops or any neurological signs/symptoms appear 2, 1
• The dosing regimens from the Eclampsia and MAGPIE trials should be used: 4g IV loading dose followed by 1g/h infusion 2

Fluid Management

• Total fluid intake should be limited to 60-80 mL/h during labor to avoid pulmonary edema risk 2
• Preeclamptic women have capillary leak and are at risk for both pulmonary edema and acute kidney injury 2

Why Intermittent Monitoring is Inadequate (Option D is Wrong)

• Intermittent auscultation is the preferred method only for healthy pregnancies without risk factors in active labor 3
• This patient's hypertension excludes her from the "low-risk" category regardless of other factors 1, 3
• The rapid progression potential of hypertensive complications during labor necessitates continuous surveillance 2, 1

Why Other Options are Incomplete

Option A (Maternal pulse and BP monitoring alone): While essential, this addresses only maternal parameters and ignores fetal surveillance, which is equally critical 1

Option B (Uterine contractions monitoring alone): Inadequate without concurrent fetal heart rate and maternal vital sign assessment 2

Option C (Early identification of complications): This is a goal, not a specific surveillance method; it requires the combination of continuous fetal monitoring and frequent maternal assessment to achieve 1

Common Pitfalls to Avoid

• Do not assume "controlled" hypertension means low-risk; labor itself can precipitate acute decompensation 1
• Do not rely on blood pressure readings alone; assess for symptoms and laboratory abnormalities 1
• Do not delay treatment of severe hypertension (≥160/110 mmHg); this requires urgent intervention within minutes to prevent maternal stroke 2
• Do not use intermittent auscultation protocols designed for truly low-risk patients 3

The correct answer is that comprehensive surveillance requires both continuous electronic fetal monitoring AND frequent maternal blood pressure/clinical assessment—no single option listed captures this completely, but continuous fetal monitoring (implied in comprehensive care) combined with maternal monitoring represents best practice for this patient. 1, 3