Individualised Blood Pressure Targets Versus Standard Care Among Critically Ill Patients With Shock

Inclusion Criteria: * ICU patients aged greater than or equal to 40 years * The patient is deemed to be in shock, defined as clinician-initiated vasopressor/inotropic therapy AND supported by any of the following within the last 24 hours: * Lactate level greater than or equal to 2 mmol/l or base deficit greater than or equal to 3 mmol/l, * Urine output less than or equal to 0.5 ml/kg/h or \<40 ml/h for 2 or more consecutive hours * Respiratory rate \>22 per minute * Altered mentation (Glasgow Coma Score \<14) Exclusion Criteria: * Patients who are moribund, or have documented not-for-resuscitation orders * At least 24 hours have lapsed from the time of initiation of vasopressor or inotropic support * Patients who are either receiving or are deemed to imminently need renal replacement therapy. * Patients who already have an increase in serum creatinine of \>350 µmol/l from baseline. * End stage renal disease * Patients where trauma is the main reason for the current ICU admission. * Previously enrolled in the REACT Shock RCT * Pregnancy, if known * Active bleeding (clinical suspicion or \>2 packed red blood cells within last 24 hours) * Insufficient (less than two) pre-illness BP readings are available. * Patients on extracorporeal support (such as extracorporeal membrane oxygenation, intra-aortic balloon pump, or ventricular assist device). * Potential contraindications to either higher or lower BP targets (including but not limited to) * Cerebral perfusion pressure guided therapy e.g. intracranial hemorrhage or subarachnoid hemorrhage or traumatic brain injury * Abdominal perfusion pressure guided therapy * Aortic injury (e.g. dissection or post-operative) * Post cardiac surgery * Any other condition requiring higher or lower BP target specifically