The provided UK guideline excerpts do not specifically detail referral criteria for "thyroid storm" NICE NG145. However, they do provide guidance on the management and referral of hyperthyroidism, of which thyroid storm is a severe manifestation.
You should consider referring adults with hyperthyroidism for specialist assessment and further treatment in secondary care NICE NG145. While awaiting specialist assessment, initial management in primary or non-specialist care may include antithyroid drugs along with supportive treatment NICE NG145.
Additionally, if a patient develops agranulocytosis while on antithyroid drugs, these drugs should be stopped immediately and not restarted, and referral to a specialist for further management options should be considered NICE NG145.