Traditional trauma teaching advocated rapidly administering 1-2 litres of normal saline to the severe trauma patient in the resuscitative phase with the aim to maintain a near normal blood pressure.
It is increasingly recognised that infusing patients with large volumes of crystalloid can be detrimental
Balanced transfusion – haemostatic resuscitation
There has been a shift now to using blood products early in hypovolaemic trauma patients. A balanced approach utilising red blood cells, platelets and plasma (in ratios of 1:1:1) has been shown to be of most benefit and is incorporated in most massive transfusion protocols.1 Use of tranexamic acid has also been studied and is likely of benefit if utilised early.2,3
Blood pressure goals
Blood pressure goals in trauma are less well defined. There has been a shift to accept a lower blood pressure (“permissive hypotension”) with the aim to prevent clot disruption in patients who have not had their injuries definitively managed.
There is limited strong evidence to support this approach. One semi-randomised study published in 1994 indicated that permissive hypotension might be of benefit in patients with penetrating torso trauma.4
Despite this, low volume trauma resuscitation has been adopted by many advanced trauma practitioners. Exact parameters have not been defined, but a SBP of 90 mmHg is commonly accepted in trauma patients with uncontrolled haemorrhage – so called “damage control resuscitation”.
A very important caveat to permissive hypotension is in patients with traumatic brain injury who need to have their cerebral perfusion pressure prioritised over the risk of clot disruption as it has been shown that even one episode of hypotension (SBP <90 mmHg) increases mortality.5
Caution also needs to be taken in patients with pre-existing hypotension or the elderly.
Other causes of hypotension (eg: tension pneumothorax) also need to be considered and addressed.
Viscoelastic haemostatic assay (VHA) guided resuscitation vs conventional coagulation testing (CCT)
Trauma‐induced coagulopathy is a derangement of haemostasis and thrombosis that develops rapidly and can be fatal if not corrected. viscoelastic haemostatic assays (thromboelastography [TEG] or rotational thromboelastometry [ROTEM]) have been developed to provide more rapid, accurate, and relatively comprehensive depictions of an individual’s coagulation profile compared with conventional coagulation testing. VHA’s may be used to augment or guide the transfusion strategy
A 2016 Cochrane Review7 concluded that TEG or ROTEM guided transfusion strategy may reduce need for blood products and improve mortality. This was with the caveat that a large proportion of the trials included were cardiac surgical, with a low level of evidence.
A recent multi-centre European RCT6 compared outcomes in adult trauma patients receiving an empiric major haemorrhage protocol (MHP) supplemented by haemostatic therapy guided by either VHA or CCTs. It did not show benefit of viscoelastic haemostatic assay augmented protocols when compared to conventional coagulation tests augmented protocols. The role of VHA in major trauma patients remains uncertain.
Whole blood transfusion versus component therapy in adult trauma patients with acute major haemorrhage
Transfusion practice in NZ has evolved to blood component (component therapy) administered in a ratio to closely approximate whole blood (WB). Using component blood reduces waste, increases storage times and allows a tailored approach to resuscitation.
However WB is currently increasingly being used in several international trauma systems. Proponents of WB note that component therapy is associated with a significantly anaemic, thrombocytopaenic, and coagulopathic product compared with whole blood, and cite several military studies suggesting a survival advantage of the early use of whole blood. Systematic reviews and small observational studies have not shown a survival benefit in transfusing WB over component therapy 8,9. There is a currently a paucity of evidence supporting the optimal transfusion strategy in critically haemorrhaging trauma
Important Aspects of History
Published: February 2018
Author: Emma Batistich
Updated: Scott Cameron (April 2021)
Approved by: Northern Region Trauma Network, ADHB, WDHB, CMDHB, NDHB, NRHL, St. John
Review due: 2 years