Prescribing Oral Rehydration Solution (ORS) involves calculating the fluid deficit, choosing the appropriate type of ORS, and instructing the patient/caregiver on its administration. Here's a detailed guide:
1. Assess the Patient's Dehydration Level
Before prescribing ORS, determine the degree of dehydration:
- Mild Dehydration: 5% weight loss, slightly dry mucous membranes, normal urine output or slightly decreased.
- Moderate Dehydration: 5-10% weight loss, dry mucous membranes, decreased skin turgor, sunken eyes, decreased urine output.
- Severe Dehydration: >10% weight loss, very dry mucous membranes, marked decrease in skin turgor, sunken eyes, minimal or no urine output, lethargy or coma. Note: Severe dehydration usually requires IV fluids, but ORS can be used cautiously if IV access is not readily available while arrangements are made.
2. Calculate the Fluid Deficit and ORS Requirement
Based on the dehydration level, calculate the approximate fluid deficit:
- Mild Dehydration: 50 mL/kg of body weight.
- Moderate Dehydration: 100 mL/kg of body weight.
Example: A 10 kg child with moderate dehydration needs approximately 10 kg * 100 mL/kg = 1000 mL of ORS.
3. Choose the Appropriate ORS Formulation
The WHO/UNICEF recommended ORS formulation is a low-osmolarity solution. Ensure you are using this type of ORS, which typically contains:
- Sodium: 75 mEq/L
- Glucose: 75 mmol/L
- Potassium: 20 mEq/L
- Chloride: 65 mEq/L
- Citrate: 10 mEq/L
4. Administer ORS According to the Following Guidelines:
- Mild Dehydration: Give 50 mL/kg over 4 hours.
- Moderate Dehydration: Give 100 mL/kg over 4 hours.
- Additional Losses: For each diarrheal stool or episode of vomiting, provide an additional 10 mL/kg (up to a maximum of 240 mL per episode).
Important Considerations During Administration:
- Small, Frequent Sips: Administer ORS in small, frequent sips (e.g., 5-10 mL every 1-2 minutes) to minimize the risk of vomiting. Use a spoon, syringe, or dropper, especially for infants.
- Persistence: If the patient vomits, wait 10 minutes and then resume administration more slowly.
- Infants: Continue breastfeeding along with ORS administration.
- Older Children: Offer ORS alongside their usual diet, if tolerated. Avoid sugary drinks, fruit juices, and carbonated beverages, as these can worsen diarrhea.
- Nasogastric (NG) Tube Administration: If the patient is unable to drink ORS, consider administering it via NG tube.
5. Reassess the Patient
- After 4 hours of ORS administration, reassess the patient's hydration status.
- If signs of dehydration persist, repeat the same volume of ORS over another 4 hours.
- If the patient’s condition worsens despite ORS administration, intravenous fluids may be necessary.
6. Educate the Caregiver
Provide clear instructions to the caregiver, including:
- How to prepare the ORS solution correctly (if using powder).
- How much ORS to give and how frequently.
- When to seek medical attention (e.g., persistent vomiting, inability to drink, worsening dehydration signs, blood in stool).
- Hygiene practices to prevent further spread of infection.
7. Monitoring
The patient should be monitored for improvement in hydration status, including:
- Improved urine output
- Moist mucous membranes
- Decreased thirst
- Improved skin turgor
- Return to baseline level of alertness
