Participant flow chart. Notes: 1. ABMUHB – Abertawe Bro Morgannwg University Health Board; CDDFT – County Durham and Darlington NHS Foundation Trust. 2. The patient or next of kin is approached for consent in the afternoon if verbal and written information about the trial is provided in the morning, or the following day if provided in the afternoon. 3. Investigational medicinal product; either 21 capsules of probiotic or placebo.