When should I consider referring a patient with severe electrolyte imbalances to secondary care?

Consider referring a patient with severe electrolyte imbalances to secondary care if any of the following apply:

• There are symptoms or signs suggesting shock or hypovolaemic shock, such as altered responsiveness, tachycardia, hypotension, prolonged capillary refill time, weak peripheral pulses, or cold extremities, as these indicate severe clinical dehydration or circulatory compromise requiring urgent specialist management.
• Severe hypernatraemia (serum sodium ≥155 mmol/l) or hyponatraemia (serum sodium <130 mmol/l) is present, especially if associated with neurological symptoms such as drowsiness, coma, convulsions, jittery movements, increased muscle tone, or hyperreflexia.
• There is a need for intravenous fluid therapy in complex cases, such as hypernatraemic dehydration, where fluid replacement must be carefully managed with specialist input to avoid rapid sodium shifts.
• Electrolyte disturbances are severe or complicated by other clinical features such as hypoglycaemia, acid–base imbalance, or renal impairment, requiring close monitoring and adjustment of therapy that cannot be safely managed in primary care.
• There is clinical deterioration or failure to respond to initial management, or if the diagnosis is uncertain and requires specialist assessment and investigations.

In children, red flag symptoms and signs indicating severe dehydration or shock mandate emergency transfer to secondary care. In adults, complications of fluid and electrolyte mismanagement such as pulmonary oedema, severe hypo- or hyperkalaemia, or hypovolaemia should prompt referral.

Overall, referral is indicated when the severity, complexity, or risk of complications from electrolyte imbalance exceeds the capacity for safe management in primary care.

References: ¹,²,³