Shock is an umbrella description for poor blood supply to vital organs and can lead to multi-organ failure and death. Emergency department (ED) patients with shock are amongst the sickest, with 1/3 being admitted to an intensive care unit (ICU). Low blood pressure, a key feature of shock which causes the poor blood supply to vital organs, can be treated with medications called vasopressors. Vasopressors traditionally have been given through a so-called 'central line'. Central lines are invasive to insert and require skill, and the actual insertion can lead to complications. More evidence has emerged that so-called peripheral lines (aka 'drip') are safe for vasopressor infusion. Randomised controlled trials (RCT) to compare the two strategies will provide high quality data to inform clinicians as to which approach is best for patients, staff and the healthcare budget. We propose a feasibility RCT to test processes and inform a large phase-III RCT to definitively answer this question. We expect that the impacts of this RCT will include: *Potentially improved patient outcomes from avoiding risks of central lines * Improved patient experience from avoiding having central line insertion * Broad applicability to low-resource settings such as rural/regional/remote areas and low-income countries *Cost savings for healthcare services through reduced use of central lines