Early high-dose cryoprecipitate to reduce mortality in adult patients with traumatic haemorrhage: the CRYOSTAT-2 RCT with cost-effectiveness analysis
Authors: Curry Nicola , Davenport Ross , Thomas Helen , Fox Erin , Lucas Joanne , Evans Amy , Massou Efthalia , Sharma Rupa , Shanmugaranjan Shaminie , Rourke Claire , Newton Alice , Deary Alison , Dallas Nikki , Fitzpatrick-Creamer Chloe , Podbielski Jeanette M , Wade Charles E , Edwards Antoinette , Benger Jonathan , Morris Stephen , Cotton Bryan A , Piercy James , Green Laura , Brohi Karim , Stanworth Simon 
Published: November 2024

Background
Traumatic haemorrhage is common after severe injury, leading to disability and death. Cryoprecipitate, a source of fibrinogen, may improve outcomes for patients with traumatic haemorrhage.

Objective
To investigate the effects of early fibrinogen supplementation in the form of 3 pools (15 units, approximately 6 g of fibrinogen) of cryoprecipitate on 28-day mortality.

Design
A randomised, parallel-group, unblinded, multicentre, international trial and economic evaluation. Patients were randomised to either the intervention (early cryoprecipitate) or the comparator (standard major haemorrhage protocol) arm via opaque, sealed envelopes in the emergency department or the transfusion laboratory/blood bank. All analyses were performed on an intention-to-treat basis. A cost-effectiveness analysis was undertaken.

Setting
Twenty-five major trauma centres in the UK and one level 1 trauma centre in the USA.

Participants
Adults who had traumatic haemorrhage following severe injury requiring activation of the major haemorrhage protocol and had received a blood transfusion.

Intervention
Early cryoprecipitate – 3 pools (equivalent to 15 single units of cryoprecipitate or 6 g of fibrinogen supplementation), infused as rapidly as possible, within 90 minutes of arrival at hospital in addition to standard major haemorrhage protocol or standard major haemorrhage protocol only.

Main outcome measures
The primary outcome was all-cause mortality at 28 days. The secondary outcomes were all-cause mortality at 6 hours, 24 hours, 6 months and 12 months from admission; death from bleeding at 6 hours and 24 hours; transfusion requirements at 24 hours from admission; destination of participant at discharge; quality-of-life measurements (EuroQol-5 Dimensions, five-level version and Glasgow Outcome Scale) at discharge/day 28 and 6 months after injury; and hospital resource use up to discharge or day 28 (including ventilator-days, hours spent in critical care and inpatient stays).

Results
Eight hundred and five patients were randomised to receive the standard major haemorrhage protocol (control arm). Seven hundred and ninety-nine patients were randomised to receive an additional three pools of cryoprecipitate in addition to standard care (intervention arm). Baseline characteristics appeared well matched. Patients had a median age of 39 (interquartile range 26–55) years, and the majority (79%) were male. All-cause 28-day mortality (n = 1531 patients; intention to treat) was 25.3% in the intervention arm compared with 26.1% in the control arm (odds ratio 0.96; p = 0.74).

Limitations
There was variability in the timing of cryoprecipitate administration, with overlap between the treatment arms, limiting the degree of intervention separation.

Conclusions
There was no evidence that early empiric administration of high-dose cryoprecipitate reduced the risk of death in unselected patients with traumatic haemorrhage. There was also no difference in adverse events. The cost-effectiveness of the intervention was similar to that of standard care.

Future work
Research to evaluate if fibrinogen replacement is more beneficial for selected patients, for example those with low fibrinogen blood levels, is needed, as is further exploration of whether there is a difference in outcome according to mechanism of injury.

Trial registration
This trial is registered as ISRCTN14998314.

Funding
This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 15/57/02) and is published in full in Health Technology Assessment; Vol. 28, No. 76. See the NIHR Funding and Awards website for further award information.