There is no certain value for how low blood pressure is shock. First of all, it is not necessarily shock if the blood pressure is low, but there is an approximate number. Generally, when the blood pressure is as low as 90/60mmHg or 80/50mmHg, it may be considered shock. Secondly, shock can also be considered when the patient’s blood pressure is more than 40 mmHg lower than his basal blood pressure, for example, if the patient’s previous blood pressure was 180/90 mmHg, suppose the blood pressure is now 120/60 mmHg. In addition, when the pulse pressure difference is less than 20 mmHg, shock should also be considered. In addition to these values, the patient’s clinical condition needs to be taken into account to see if the patient has any signs of hypoperfusion, such as if the patient has panic attacks, poor peripheral circulation, cold sweats, or even cyanosis, or pallor, or low urine, before shock can be considered.