Permissive Hypotension

Abstract

Permissive hypotension in the context of life-threatening haemorrhage is a resuscitation strategy which is used within damage control resuscitation, in which a lower than normotensive blood pressure is targeted until the source of haemorrhage is controlled. The perceived benefit of permissive hypotension is that it limits bleeding and prevents dislodging of any clot formed at the injury site by avoiding excessively high blood pressures. The dangers of large fixed-volume fluid resuscitation were highlighted throughout the twentieth century; however, it was not until the turn of the century where various strategies limiting crystalloid resuscitation started to emerge. This included volume restricting, delaying fluid administration or titrating fluid administration to a lower than normal systolic blood pressure. A balance needs to be struck between an exacerbating bleeding and the accumulation of the effects of prolonged hypoperfusion and shock. Novel hybrid resuscitation and the availability of blood products in the pre-hospital environment are natural progressions in the concept of damage control resuscitation and may form the next iteration of new resuscitation strategies.