Shock is a life-threatening condition of circulatory failure that most commonly presents with hypotension. The effects of shock are initially reversible but can rapidly become irreversible, resulting in multiple organ failure and death. If a patient presents with undifferentiated hypotension and is suspected of having shock, it is important the cause is identified and the hypotension managed to prevent multiple organ failure and death.1
There are several different clinical situations that require explicit blood pressure targets. In critical care, this includes the septic patient, with and without pre-existing renal impairment, haemorrhagic shock and the patient with a head injury. Current guidelines in the trauma patient are to keep the systolic blood pressure greater than 90 mmHg, but this is in the prehospital setting and prior to control of haemorrhage. In the patient with an isolated head injury and the absence of haemorrhagic shock, a MAP of 80 mmHg or above is recommended.
The largest patient group passing though in the ICU are those patients with septic shock. In the septic patient, the Surviving Sepsis Campaign recommends targeting a MAP of 65 mmHg or above.2 These recommendations are supported by the SEPSISPAM study, which randomised 776 patients with septic shock to either
80-85 mmHg (high-target group) or 65-70 mmHg (low- target group).3 There was no difference in mortality at 28 or 90 days between the two groups.3 Aiming for a higher blood pressure in the critically ill patient is associated with an increased incidence of supraventricular arrhythmias.4
