How to manage a 22-week pregnant patient with hyperemesis gravidarum, tachycardia, and normal blood pressure, who has failed Zofran (ondansetron) therapy?

From the Guidelines

For a 22-week pregnant patient with hyperemesis gravidarum, tachycardia, and normal blood pressure who has failed ondansetron therapy, I recommend hospital admission for IV fluid rehydration and escalated antiemetic therapy, starting with metoclopramide 10mg IV/PO every 6 hours, as it has been shown to have similar efficacy to promethazine with fewer side effects 1.

Management Approach

The goals of management are to prevent dehydration, correct electrolyte abnormalities, and support adequate maternal and fetal nutrition.

• IV fluid rehydration is essential to correct dehydration and electrolyte imbalances.
• Metoclopramide can be given for nausea and vomiting, as it enhances gastric emptying and has been shown to be effective in patients with hyperemesis gravidarum 1.
• Consider adding a histamine-2 receptor antagonist like famotidine 20mg twice daily to reduce gastric acid production.
• Monitor electrolytes (particularly potassium, sodium, chloride, and magnesium) and replace as needed.
• Assess for ketosis and provide thiamine supplementation (100mg daily for 3 days, then 50mg daily) to prevent Wernicke's encephalopathy 1.

Nutrition and Follow-up

Once vomiting is controlled, gradually reintroduce oral nutrition, starting with clear liquids and progressing to small, frequent meals low in fat and spice.

• The patient should be closely monitored for signs of dehydration, electrolyte imbalances, and nutritional deficiencies.
• Follow-up appointments should be scheduled to assess the patient's response to treatment and make any necessary adjustments to the management plan.

Considerations

The use of corticosteroids, such as methylprednisolone, may be considered as a last resort in patients with severe hyperemesis gravidarum, but their use should be weighed against the potential risks and benefits 1. The patient's mental health should also be assessed, as hyperemesis gravidarum can have a significant impact on anxiety and depression, and referral to a mental health professional may be necessary 1.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Management of Hyperemesis Gravidarum

The patient is a 23-year-old female who is 22 weeks pregnant with excessive vomiting, tachycardia, and normal blood pressure, who has failed Zofran (ondansetron) therapy. The management of this patient can be approached as follows:

• Assessment of Severity: The severity of nausea and vomiting can be assessed using objective and validated indices such as the Pregnancy-Unique Quantification of Emesis (PUQE) and HyperEmesis Level Prediction (HELP) tools 2.
• AntiEmetic Therapy: Since the patient has failed Zofran (ondansetron) therapy, other antiemetic options can be considered. Metoclopramide is safe and effective and can be used alone or in combination with other antiemetics 2. Granisetron, a 5-HT3-receptor antagonist, has also been shown to be effective in controlling nausea and vomiting in pregnancy 3.
• Intravenous Hydration: Normal saline (0.9% NaCl) with additional potassium chloride in each bag, with administration guided by daily monitoring of electrolytes, is the most appropriate intravenous hydration 2.
• Thiamine Supplementation: Thiamine supplementation (either oral 100 mg tds or intravenous as part of vitamin B complex) should be given to all women admitted with vomiting, or severely reduced dietary intake, especially before administration of dextrose or parenteral nutrition 2.
• Parenteral Nutrition: If the patient's condition does not improve with antiemetic therapy and intravenous hydration, parenteral nutrition can be considered. Total parenteral nutrition has been shown to be a safe and effective method of nutritional support during pregnancy 4, 5. Peripheral parenteral nutrition is also an option, which reduces the risk of complications, but caloric intake is limited 6.

Monitoring and Follow-up

The patient's condition should be closely monitored, and adjustments made to the management plan as needed. The patient's vitals, including pulse and blood pressure, should be regularly checked, and electrolyte levels monitored daily. The patient's response to antiemetic therapy and intravenous hydration should also be closely monitored.