Critical closing pressure

An example of this phenomenon is measurement of blood pressure using the "pulse obliteration method" with a sphygmomanometer.

At resting state the arterial critical closing pressure is ~ 20 mmHg.

Therefore, arteries collapse after death, then fill up with air once the dissection begins.

In severe haemorrhage, blood loss leads to a significant reduction in circulatory system arterial pressures.

This abrupts blood supply to tissues, otherwise termed shock.