Acute Severe Ulcerative Colitis

A 24-year-old man with a 3-year history of ulcerative colitis presents with 12 episodes of bloody diarrhoea daily, fever 38.6°C, tachycardia 118 bpm, hemoglobin 8.4 g/dL, ESR 78, and CRP 124 mg/L. Flexible sigmoidoscopy shows continuous confluent erythema, friability, deep ulcerations, and spontaneous bleeding from rectum to descending colon, confirming acute severe ulcerative colitis (ASUC) by Truelove & Witts criteria. The management pathway marked **A** in the diagram outlines the standard approach to this patient. Which of the following is NOT part of the initial management strategy outlined in pathway **A** for acute severe ulcerative colitis?