What is the initial treatment for hyperemesis gravidarum in an inpatient setting?

Initial Inpatient Treatment for Hyperemesis Gravidarum

The initial inpatient treatment for hyperemesis gravidarum should include intravenous fluid and electrolyte replacement, IV thiamine supplementation, and IV antiemetics, with early intervention to prevent complications. 1

Evaluation and Assessment

• Diagnosis criteria: Hyperemesis gravidarum is characterized by:

  • Intractable nausea and vomiting
  • Dehydration
  • Weight loss >5% of pre-pregnancy weight
  • Electrolyte imbalances 2, 1

• Laboratory evaluation:

  • Electrolytes
  • Liver function tests
  • Urinalysis for ketones
  • Thyroid function tests 1

• Physical examination: Focus on signs of dehydration (orthostatic hypotension, decreased skin turgor, dry mucous membranes) and malnutrition 2

Initial Inpatient Management Algorithm

Step 1: Stabilization and Rehydration

• IV fluid replacement with normal saline and glucose
• Correction of electrolyte abnormalities
• Immediate thiamine supplementation: 100 mg IV/IM if unable to tolerate oral medication or if clinical suspicion of acute deficiency exists 1
  • Critical to administer before glucose to prevent precipitating Wernicke's encephalopathy

Step 2: Antiemetic Therapy

Start with first-line IV antiemetics:

• Metoclopramide (can be used for NVP and HG) 1
• Promethazine (considering side effect profile) 1
• Ondansetron (use with caution before 10 weeks gestation) 1

Step 3: For Refractory Cases

If symptoms persist despite first-line treatments:

• Methylprednisolone: 16 mg IV every 8 hours for up to 3 days, followed by tapering over 2 weeks 1
  • Maximum duration: 6 weeks
  • Has been shown to reduce rehospitalization rates for severe HG 1

Nutritional Support

• Once vomiting is controlled, transition to oral intake with:
  • Small, frequent, bland meals
  • High-protein, low-fat foods
  • BRAT diet (bananas, rice, applesauce, toast) 2, 1
• Vitamin supplementation:
  • Thiamine: 200-300 mg daily orally (once able to tolerate) 1
  • Pyridoxine (vitamin B6): 10-25 mg every 8 hours 2, 1

Monitoring During Hospitalization

• Daily weight
• Intake and output
• Electrolyte levels
• Liver function tests (if initially abnormal)
• Signs of thiamine deficiency 1
• For patients on corticosteroids:
  • Screen for gestational diabetes
  • Monitor for signs of adrenal suppression 1

Important Considerations and Pitfalls

• Critical pitfall: Failure to administer thiamine before glucose can precipitate Wernicke's encephalopathy, which can lead to chronic cognitive disorders, pregnancy loss, and maternal death 1

• Discharge criteria:

  • Ability to maintain adequate oral hydration
  • Controlled symptoms with oral medications
  • No significant electrolyte abnormalities
  • Weight stabilization

• Follow-up: Regular outpatient monitoring is essential as recurrence risk is high, with approximately 4-27% of patients requiring readmission 3

• Alternative therapies for truly refractory cases:

  • Consider mirtazapine, olanzapine, or gabapentin 4
  • Enteral or parenteral nutrition may be necessary in prolonged cases with ongoing weight loss 4

Early and aggressive treatment is essential to prevent complications such as Wernicke's encephalopathy, central pontine myelinolysis, low birth weight, premature delivery, and in rare cases, maternal death 1, 5.