Permissive hypotension compared to fluid therapy for the management of traumatic haemorrhage: a rapid review

Background: Haemorrhage and subsequent hypovolemia from traumatic injury is a potentially reversible cause of cardiac arrest, as interventions can be made to increase circulatory volume and organ perfusion. Traditionally, intravenous (IV) fluid therapy is recommended for all
 patients who have experienced a haemorrhagic emergency. There has been some argument, however, that this may not be the most effective treatment as isotonic fluids can dilute coagulation factors and further stimulate bleeding. Permissive hypotension, also known as hypotensive resuscitation
 within the context of damage control resuscitation, is a method of managing haemorrhagic trauma patients by restricting IV fluid administration to allow for a reduced blood pressure. It is important to evaluate and compare current research literature on the effects of both permissive hypotension
 and fluid therapy on patients suffering from traumatic haemorrhage.Methods: A rapid review was conducted by systematically searching and identifying literature to narratively compare permissive hypotension and fluid therapy. Searches were carried out across two databases to find
 relevant primary research containing quantitative data that provide contextual and statistical evidence to achieve the aim of this review. Papers were narratively synthesised to produce key themes for discussion.Results: The database searches identified 125 records, 78 from PubMed
 and 47 from ScienceDirect. Eleven duplicates were removed, and 114 titles screened. Ninety-four records were initially excluded and nine more after abstract review. Eleven papers were critiqued using Benton and Cormack's framework, with eight articles included in the final review.Conclusion:
 Permissive hypotension may have a positive impact on 30-day mortality, when compared with fluid resuscitation methods, however there is evidence to suggest that hypotensive resuscitation may be more effective for blunt force injuries. Some studies even suggest a reduction in the treatment
 cost when reducing fluid volumes. Penetrating injuries are usually more likely to be a compressible source of haemorrhage within which haemorrhage control can be gained much more easily. There are recommendations for the use of permissive hypotension in both compressible and non-compressible
 injuries. It is difficult at this time to draw definitive conclusions for the treatment of every case related to traumatic haemorrhage given the variability and unpredictability of trauma.