How can I assess the severity of dehydration in a patient with hyperemesis gravidarum, and when should I consider intravenous fluids?

Assessing severity of dehydration in hyperemesis gravidarum: Evaluate clinical signs such as altered responsiveness (irritability, lethargy), sunken eyes, dry mucous membranes, tachycardia, tachypnoea, prolonged capillary refill time, reduced skin turgor, decreased urine output, pale or mottled skin, and cold extremities. Presence of these signs indicates clinical dehydration or more severe hypovolaemic shock. Monitor vital signs including blood pressure, heart rate, respiratory rate, and capillary refill time. Use the National Early Warning Score (NEWS) if available to assess severity. Consider laboratory tests (plasma sodium, potassium, urea, creatinine, glucose) if intravenous fluids are needed or hypernatraemia is suspected. Assess for signs of shock such as hypotension, decreased consciousness, and weak peripheral pulses.

When to consider intravenous fluids: Initiate intravenous fluid therapy if the patient shows evidence of clinical dehydration with inability to tolerate oral fluids or antiemetics, persistent vomiting despite oral treatment, signs of hypovolaemic shock, weight loss greater than 5% of body weight, or if there is a PUQE score greater than 13. Also consider IV fluids if there is clinical evidence of deterioration despite oral rehydration or if oral intake is not possible. Hospital admission and IV fluids are recommended for severe or refractory symptoms, complications, or co-morbidities preventing oral treatment.

In summary, assess dehydration severity clinically and with vital signs; start IV fluids when oral rehydration fails, dehydration is moderate to severe, or shock is suspected, especially in hyperemesis gravidarum patients with significant weight loss or inability to tolerate oral treatment.

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