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Foundational Trials

PROPPR

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Publication

  • Title: Transfusion of Plasma, Platelets, and Red Blood Cells in a 1:1:1 vs a 1:1:2 Ratio and Mortality in Patients With Severe Trauma: The PROPPR Randomized Clinical Trial.
  • Acronym: PROPPR — Pragmatic, Randomized Optimal Platelet and Plasma Ratios.
  • Year: 2015.
  • Journal published in: JAMA.
  • Citation: Holcomb JB, Tilley BC, Baraniuk S, Fox EE, Wade CE, Podbielski JM, et al; PROPPR Study Group. Transfusion of plasma, platelets, and red blood cells in a 1:1:1 vs a 1:1:2 ratio and mortality in patients with severe trauma: the PROPPR randomized clinical trial. JAMA. 2015;313(5):471–482.

Context & Rationale

  • Background
    • Traumatic haemorrhage requires simultaneous restoration of oxygen delivery, correction of coagulopathy and definitive bleeding control.
    • Military and civilian observational evidence had encouraged early plasma and platelet administration, replacing resuscitation dominated by crystalloid and red blood cells (RBCs).
    • PROMMTT associated higher early plasma:RBC and platelet:RBC ratios with lower early mortality using time-dependent analyses. Residual confounding remained, and patients who survived longer had more opportunity to receive plasma and platelets. Randomisation was needed to distinguish treatment benefit from survival-related differences in treatment exposure. 1
  • Research Question/Hypothesis
    • Would early plasma:platelets:RBC transfusion in a 1:1:1 ratio improve survival compared with 1:1:2 in severely injured patients predicted to require massive transfusion?
    • The comparison concerned two active component-resuscitation strategies, with different plasma and platelet provision during ongoing bleeding.
  • Why This Matters
    • The initial transfusion decision often precedes complete laboratory information and must be implemented within minutes.
    • A survival advantage would justify greater early plasma and platelet use; uncertainty matters because these components require donors, inventory, preparation and delivery capacity.

Design & Methods

  • Research Question:
    • Whether initial 1:1:1 rather than 1:1:2 component transfusion reduces all-cause mortality at 24 hours and 30 days after randomisation.
  • Study Type:
    • Investigator-initiated, pragmatic, phase III, multicentre, international, parallel-group superiority randomised trial.
    • Twelve level I trauma centres in the USA and Canada; recruitment from 3 August 2012 to 2 December 2013.
    • Allocation was 1:1, stratified by site, using randomly varying permuted blocks and blood-bank-held allocation lists.
    • Emergency enrolment used exception from informed consent, community consultation and subsequent patient or legally authorised representative consent.
    • Public funding included the US National Heart, Lung, and Blood Institute, US Department of Defense and Canadian research support.
  • Population:
    • Highest-level trauma activation, direct admission from the injury scene, estimated age ≥15 years or weight ≥50 kg if age was unknown.
    • At least one blood-component unit started before hospital arrival or within the first hour after arrival.
    • Predicted massive transfusion, defined as ≥10 RBC units within 24 hours, using an Assessment of Blood Consumption score ≥2 or attending trauma physician judgement.
    • Patients had to enter before receiving more than three RBC units and receive randomised products within two hours of emergency department arrival.
    • Major exclusions included preceding lifesaving treatment at another hospital, expected death within one hour from devastating injury, emergency thoracotomy before randomised products, more than five consecutive minutes of cardiopulmonary resuscitation, known pregnancy, burns involving >20% of body surface area, suspected inhalation injury, pre-existing treatment limitations or refusal of blood.
    • Of 11,185 screened patients, 680 were randomised: 338 to 1:1:1 and 342 to 1:1:2.
  • Intervention:
    • 1:1:1 plasma:platelets:RBC: each container contained six plasma units, one adult platelet dose and six RBC units.
    • One adult platelet dose represented one apheresis unit or a pool of approximately five to six whole-blood-derived platelet units. The ratio therefore does not mean one apheresis platelet unit per RBC unit.
    • Platelets were administered first, followed by alternating RBC and plasma units; concurrent administration was permitted through multiple intravenous lines.
    • The blood bank targeted delivery within ten minutes of notification and prepared further containers while transfusion continued.
    • Study transfusion stopped when clinically indicated, including haemostasis, death, futility or no further transfusion requirement, even if a container was incomplete or its nominal ratio had not been reached. 2
  • Comparison:
    • 1:1:2 plasma:platelets:RBC: odd-numbered containers contained three plasma units, no platelets and six RBC units.
    • Even-numbered containers contained three plasma units, one adult platelet dose and six RBC units.
    • Two RBC units alternated with one plasma unit; platelets were given first when a platelet-containing container arrived.
    • Thus, scheduled platelets first appeared in the second container, after the initial six study RBC units.
    • After the study transfusion phase, both groups received transfusion according to local laboratory results and clinical judgement.
    • Definitive haemorrhage control, tranexamic acid, cryoprecipitate, other haemostatic agents and non-blood fluids were not standardised by randomised assignment. 2
  • Blinding:
    • Initial containers were sealed, with sham platelet bags where required; randomisation occurred when the seal was broken.
    • Bedside clinicians were then unblinded. Deaths underwent external cause-of-death adjudication by a clinician blinded to allocation.
  • Statistics:
    • Initially, 580 participants provided 90% power (β=0.10) to detect a 10 percentage-point reduction in 24-hour mortality (21% to 11%) and 88% power (β=0.12) to detect a 12-point reduction in 30-day mortality (35% to 23%), with two-sided α=0.05 and a final threshold of 0.044 after interim monitoring.
    • A prespecified sample-size reassessment increased recruitment to 680, before review of comparative treatment results, to maintain power above 85%.
    • Two planned interim analyses used Lan–DeMets boundaries approximating O’Brien–Fleming monitoring.
    • The co-primary mortality outcomes were tested separately using site-adjusted Mantel–Haenszel tests; no additional adjustment was made between the two co-primary tests.
    • Analysis followed randomised assignment. Missing 30-day mortality was examined using every possible combination of outcomes for the four patients concerned.
    • Ancillary analyses were exploratory, without multiplicity adjustment; the statistical analysis plan specified descriptive presentation of cause-of-death data. 2
  • Follow-Up Period:
    • All-cause mortality at 24 hours and 30 days after randomisation, including follow-up after hospital discharge.
    • Ancillary outcomes included haemostasis, blood-product use, organ-support-free days, complications and discharge status.
    • Published anatomical haemostasis meant surgical control of bleeding with no further haemostatic intervention anticipated, or resolution of contrast extravasation after embolisation.

Key Results

This trial was not stopped early. It completed the revised target of 680 participants after two planned interim analyses. Ratios below are plasma:platelets:RBC; RD denotes the published risk difference in percentage points, and values in parentheses following medians are interquartile ranges.

Outcome 1:1:1 (n=338) 1:1:2 (n=342) Effect p value / 95% CI Notes
24-hour all-cause mortality 43/338 (12.7%) 58/342 (17.0%) Adjusted RR 0.75;
RD −4.2 points		 RR 95% CI 0.52 to 1.08;
RD 95% CI −9.6 to 1.1;
P=0.12		 Co-primary outcome; superiority not demonstrated.
30-day all-cause mortality 75/335 (22.4%) 89/341 (26.1%) Adjusted RR 0.86;
RD −3.7 points		 RR 95% CI 0.65 to 1.12;
RD 95% CI −10.2 to 2.7;
P=0.26		 Co-primary outcome; observed-status denominators exclude three versus one missing outcomes.
Death from exsanguination by 24 hours 31/338 (9.2%) 50/342 (14.6%) RD −5.4 points 95% CI −10.4 to −0.5;
P=0.03		 Exploratory cause-specific comparison.
Death from exsanguination by 30 days 36/335 (10.7%) 50/341 (14.7%) RD −3.9 points 95% CI −9.1 to 1.2;
P value not reported		 No clear difference at this later time point.
Achieved haemostasis 291/338 (86.1%) 267/342 (78.1%) Relative effect not reported P=0.006;
95% CI not reported		 More patients achieved haemostasis with 1:1:1.
Time to anatomical haemostasis, minutes 105 (64–179) 100 (56–181) Between-group estimate not reported P=0.44;
95% CI not reported		 Among patients achieving haemostasis; no demonstrated acceleration.
Plasma transfused by 24 hours, units 7 (3–13) 5 (2–10) Between-group estimate not reported P<0.001;
95% CI not reported		 Includes pre-randomisation, intervention and subsequent transfusion. 3
Platelets transfused by 24 hours, donor-unit equivalents 12 (6–18) 6 (0–12) Between-group estimate not reported P<0.001;
95% CI not reported		 Approximately six donor units constitute one adult dose. 3
RBCs transfused by 24 hours, units 9 (5–15) 9 (6–16) Between-group estimate not reported P=0.30;
95% CI not reported		 No demonstrated RBC-sparing effect. 3
Acute respiratory distress syndrome 46 (13.6%) 48 (14.0%) RD −0.4 points 95% CI −5.7 to 4.9;
P value not reported		 No detected difference.
Multiple organ failure 20 (5.9%) 15 (4.4%) RD 1.5 points 95% CI −1.9 to 5.1;
P value not reported		 No detected difference.
Deep vein thrombosis 25 (7.4%) 24 (7.0%) RD 0.4 points 95% CI −3.6 to 4.4;
P value not reported		 No detected difference.
Symptomatic pulmonary embolism 14 (4.1%) 13 (3.8%) RD 0.3 points 95% CI −2.8 to 3.5;
P value not reported		 No detected difference.
Transfusion-associated circulatory overload 1 (0.3%) 0 RD 0.3 points 95% CI −0.8 to 1.7;
P value not reported		 The event in the 1:1:1 group was fatal.
  • Mortality:
    • Both co-primary estimates favoured 1:1:1, but their confidence intervals included no effect and some harm; neither met the prespecified significance threshold.
    • The intervals also permit clinically substantial benefit. Failure to demonstrate superiority does not establish equivalence.
  • Haemostatic efficacy and recovery:
    • Fewer early exsanguination deaths and more patients achieving haemostasis support a coherent haemostatic benefit, but these exploratory outcomes do not replace the co-primary outcomes.
    • Median ventilator-free days were 8 (0–16) versus 7 (0–14), P=0.14; ICU-free days were 5 (0–11) versus 4 (0–10), P=0.10. These comparisons included 337 versus 340 patients; the published definition assigned zero free days to patients dying within the first 24 hours.
    • No validated treatment-defining subgroup was established in the index report.
  • Transfusion burden and harms:
    • Median total component use through 24 hours was 25.5 versus 19 units, with greater plasma and platelet exposure in the 1:1:1 group.
    • No difference was detected in any of 23 prespecified complications; the study nevertheless cannot establish equivalent safety for uncommon adverse events.

Internal Validity

  • Randomisation and allocation:
    • Site stratification, variable block sizes and concealed first containers protected allocation before treatment began.
    • Breaking the seal defined randomisation; patients whose unused containers were returned before opening were not post-randomisation exclusions.
  • Retention and missing outcomes:
    • Randomised products were administered to 669 of 680 participants; allocation-based analysis retained the randomised groups.
    • Consent was withdrawn by 18 versus 17 participants by 30 days, but available vital-status information was retained.
    • Mortality ascertainment was complete at 24 hours and 99.4% complete at 30 days; only three versus one 30-day outcomes were missing.
    • All 16 missing-outcome combinations in the supplement left the 30-day comparison statistically inconclusive. Attrition is unlikely to explain the principal result. 3
  • Performance and outcome assessment:
    • Treating clinicians knew allocation after container opening and controlled further transfusion and haemostatic interventions.
    • All-cause mortality was objective; cause-of-death adjudication was blinded, whereas anatomical haemostasis depended on clinical or angiographic assessment.
    • More than one cause could be attributed to a death; cause-specific categories cannot simply be added together.
  • Baseline balance and biological opportunity:
    • Median age was 34.5 versus 34 years, and median Injury Severity Score was 26.5 versus 26.
    • Penetrating injuries occurred in 46.4% versus 50.6%; systolic blood pressure ≤90 mmHg was recorded in 38.5% versus 39.0% of those with available measurements.
    • Median base excess was −8.0 versus −8.5 mmol/L, supporting substantial physiological insult without requiring terminal shock.
    • Documented laboratory coagulopathy was not an eligibility requirement; median admission INR was 1.3 in both groups.
  • Timing and treatment delivery:
    • Median time from arrival to randomisation was 27.5 (17–47) versus 25.5 (16–41) minutes.
    • Both groups received a median of two blood-component units before randomisation; the assigned strategy therefore did not begin with the first transfused unit.
    • Mean proportions of study units delivered out of sequence were 4% versus 7%, P=0.01; sensitivity analyses excluding affected patients gave similar primary results.
  • Separation, dose and subsequent treatment:
    • During the intervention, median plasma:RBC ratios were 1.0 versus 0.5 and platelet:RBC ratios were 1.5 versus 0.4.
    • Separation was therefore achieved during active treatment despite incomplete containers and variable transfusion requirements.
    • Afterwards, the 1:1:2 group received proportionally more plasma and platelets, narrowing cumulative ratio differences. This was permitted subsequent care rather than wholesale reassignment.
    • These subsequent treatments form part of the total effect of the assigned strategy; treating them as baseline confounders would distort the randomised comparison.
    • By 24 hours, platelets had been administered to 98.5% versus 59.9% of participants. 3
  • Adjunctive therapies:
    • Tranexamic acid was used in 64/338 (18.9%) versus 68/342 (19.9%).
    • Cryoprecipitate was used in 73/338 (21.6%) versus 100/342 (29.2%); median quantities were 0 (0–0) versus 0 (0–9) units, P=0.01.
    • Median crystalloid exposure was 6.3 (3.8–9.5) versus 6.6 (3.5–10.5) litres, P=0.58. 3
  • Heterogeneity and statistical integrity:
    • Different injury patterns, bleeding sources and centre practices make this an average treatment-effect estimate across a heterogeneous emergency population.
    • Site-adjusted analyses supported the randomisation scheme, and the sample-size change followed a prespecified process rather than the observed between-group effect.
    • The SAP treated ancillary analyses as exploratory and subgroup findings as requiring confirmation. 2

Conclusion on Internal Validity: Internal validity is strong for estimating the effect of assignment to these two initial resuscitation strategies on all-cause mortality. Confidence in a definitive haemostatic or safety advantage is more limited by exploratory testing, outcome assessment and imprecision.

External Validity

  • Population representativeness:
    • The findings apply most directly to predominantly young, severely injured, bleeding patients reaching a major trauma centre directly from the scene.
    • Women, older adults and patients with comorbid coagulopathy were less well represented; children, pregnancy and several moribund presentations were excluded.
    • Approximately half the cohort had penetrating injuries, affecting transportability to systems dominated by blunt trauma.
    • The trial does not directly establish component ratios for gastrointestinal, obstetric, cardiac surgical or other non-traumatic haemorrhage.
  • Systems and implementation:
    • Participating centres could provide thawed plasma, platelets, RBCs and rapid operative or interventional radiological haemorrhage control.
    • Resource-limited hospitals, interhospital transfers and prolonged prehospital care may have different treatment delays, inventory constraints and opportunities for benefit.
    • Only 78% of highest-level activations were screened, so logistical trial eligibility also shaped the recruited population.
  • Contemporary applicability:
    • Current pathways incorporate early tranexamic acid, fibrinogen assessment or replacement and laboratory- or viscoelastic-guided treatment. PROPPR did not isolate the incremental effect of its ratio comparison within each of these pathways. 4
    • The tested intervention was an initial response to active bleeding, followed by clinical and laboratory reassessment; it was not a requirement to maintain 1:1:1 for 24 hours.

Conclusion on External Validity: Generalisability is good for comparable major trauma systems with rapid component availability. It is substantially narrower for non-traumatic haemorrhage, excluded populations, delayed presentations and services unable to reproduce early delivery.

Strengths & Limitations

  • Strengths:
    • Randomised comparison of clinically credible strategies during a difficult, time-critical phase of trauma care.
    • Concealed allocation, meaningful early treatment separation and direct observation of transfusion delivery.
    • Objective co-primary outcomes, blinded death adjudication and near-complete mortality follow-up.
    • Public protocol and SAP, prespecified adaptive recruitment and detailed reporting of component exposure and complications.
  • Limitations:
    • Precision was insufficient to resolve smaller but clinically important mortality effects.
    • Unblinded bedside care and clinician-assessed haemostasis.
    • Simultaneous changes in plasma provision, platelet dose and platelet timing prevent identification of the active component.
    • Exploratory outcome testing, subsequent convergence of treatment and limited information about uncommon harms or long-term functional recovery.

Interpretation & Why It Matters

  • Clinical meaning
    • PROPPR supports early access to plasma and platelets during severe traumatic bleeding and provides a reasonable basis for choosing 1:1:1 when massive transfusion is anticipated.
    • The strongest favourable findings concern achieving haemostasis and avoiding early exsanguination; an all-cause survival advantage remains uncertain.
  • What changed
    • The trial replaced inference from achieved transfusion ratios with randomised evidence about an early treatment strategy.
    • Its operational lesson is that platelets and plasma can be delivered promptly alongside RBCs, with treatment stopped or adapted as bleeding resolves.
  • Decision under uncertainty
    • Choosing 1:1:1 can be justified by the balance of plausible benefit, haemostatic findings and observed harms without claiming proven superiority for survival.
    • PROPPR did not establish that 1:1:2 is equivalent, that a precise ratio should override clinical need, or that component ratios can substitute for definitive haemorrhage control.

Controversies & Other Evidence

  • Large target effects and inconclusive primary outcomes:
    • The trial sought absolute mortality reductions of 10 and 12 percentage points. Observed reductions were smaller, and control mortality was lower than anticipated: 17.0% rather than 21% at 24 hours and 26.1% rather than 35% at 30 days.
    • High power for the original large effects does not exclude smaller worthwhile effects. Conversely, imprecision cannot be used to declare that the observed benefit is real. The published debate about absent primary-outcome significance must be resolved by the estimates and confidence intervals, rather than either categorical interpretation. 5
    • The prespecified increase to 680 participants was methodologically defensible; failure to meet the mortality endpoints cannot be attributed to premature stopping.
  • Endpoint choice, competing causes of death and multiplicity:
    • Severe brain injury and later organ failure can reduce the sensitivity of all-cause mortality to an intervention directed at early bleeding. This was raised in the published correspondence; however, all-cause mortality remains the most robust measure of net survival benefit. 6
    • The authors defended exsanguination and haemostasis as clinically important, prospectively identified outcomes, with blinded adjudication of death. The distinction is that prospective identification does not make their statistical comparisons confirmatory: the supplied SAP explicitly designated ancillary analyses exploratory and cause-of-death presentation descriptive. 72
    • No multiplicity adjustment was applied across ancillary outcomes or between the two co-primary tests. The haemostasis and exsanguination findings are supportive, correlated observations rather than independent confirmations of a mortality benefit.
    • Between 24 hours and 30 days, there were 32 additional deaths with 1:1:1 and 31 with 1:1:2. The data do not demonstrate that excess late deaths cancelled an early survival benefit.
  • Haemostasis was achieved more often, without demonstrated faster achievement:
    • The 105-versus-100-minute comparison was restricted to patients who achieved haemostasis. Because treatment may affect both survival and achievement, this conditional comparison does not estimate an unbiased treatment effect on time to haemostasis in all randomised patients.
    • The supplied February 2012 SAP described haemostasis as two hours without further transfusion, whereas the publication used anatomical haemostasis. This difference in operational definition, alongside unblinded assessment, warrants caution in giving this endpoint decisive weight. 2
  • Ratio, timing and resource use cannot be disentangled:
    • Immediate platelets in the 1:1:1 arm were compared with scheduled platelets beginning in the second container in the 1:1:2 arm. The trial therefore cannot establish whether plasma quantity, platelet quantity, earlier platelet delivery or their combination produced the haemostatic findings.
    • Later convergence of cumulative ratios does not erase the randomised comparison during active bleeding. It does mean the result applies to an initial strategy followed by local care.
    • The authors argued that improved haemostasis and fewer exsanguination deaths justified greater 24-hour component use. That is a clinical value judgement supported by secondary findings; PROPPR did not demonstrate RBC conservation or establish the most cost-effective component strategy. 7
  • Defining the patients who can benefit:
    • Only 45.3% versus 46.8% ultimately received ≥10 RBC units within 24 hours. This does not establish that most patients were inappropriately enrolled: early death or successful haemostasis can both prevent a patient reaching that threshold.
    • Restricting analysis to patients who actually received massive transfusion would condition on a post-randomisation event affected by treatment and survival. The SAP explicitly recognised the resulting bias; such subsets cannot reliably identify a treatment-responsive phenotype. 2
  • Bayesian reanalysis:
    • A 2023 post hoc hierarchical Bayesian analysis estimated probabilities of mortality benefit of 93% at 24 hours and 87% at 30 days. The main results gave RR 0.72, 95% credible interval 0.45 to 1.11, and RR 0.82, 95% credible interval 0.57 to 1.16, respectively. 8
    • These probabilities describe the same trial data under the chosen model and prior; they add no independent patients. The analysis used a non-informative prior without a range of informative-prior sensitivity analyses, and the credible intervals still included harm. 8
    • The accompanying commentary highlighted the usefulness of quantifying benefit probabilities while warning against replacing one arbitrary significance threshold with another. The useful question is the probability and magnitude of clinically worthwhile benefit, considered alongside component use and harms. 9
  • Fixed ratios and targeted haemostatic treatment:
    • PROPPR did not randomise fixed-ratio resuscitation against a laboratory- or viscoelastic-guided strategy.
    • ITACTIC subsequently compared viscoelastic with conventional coagulation testing on a background of empirical 1:1:1 transfusion and tranexamic acid. Among 396 analysed patients, 67% versus 64% were alive and free of massive transfusion at 24 hours; OR 1.15, 95% CI 0.76 to 1.73. This tests how to augment an initial haemorrhage protocol, rather than whether to omit empirical haemostatic treatment. 10
  • Systematic review and remaining replication gap:
    • The 2025 Cochrane review included 18 trials overall, but its direct 1:1:1-versus-1:1:2 mortality comparison still rested on PROPPR alone. It graded that comparison as moderate-certainty evidence and described probably little or no mortality difference.
    • Interpretation of this review requires recognising that it does not establish equivalence: the underlying interval remains compatible with a worthwhile survival benefit. The review searched to November 2023, so its publication date should not be mistaken for coverage of the subsequent 2026 trials. 11
  • Guidelines support early balanced resuscitation while preserving flexibility:
    • The 2023 European trauma guideline recommends initial fibrinogen concentrate or cryoprecipitate with RBCs, or plasma:RBC at least 1:2, with a high platelet:RBC ratio suggested; subsequent treatment should be guided by coagulation assessment. It does not require universal 1:1:1 resuscitation. 4
    • The 2021 ESICM guideline conditionally supports high-ratio transfusion for traumatic massive bleeding, with low-certainty evidence, and identifies 1:1:1 as a reasonable empirical starting strategy. It makes no corresponding recommendation for non-traumatic massive bleeding. 12
  • Whole-blood trials address a distinct contemporary question:
    • In SWiFT, published in 2026, prehospital whole blood versus RBC-plus-plasma components produced death or massive transfusion within 24 hours in 48.7% versus 47.7%; RR 1.02, 95% CI 0.80 to 1.31; P=0.84. 13
    • In TOWAR, also published in 2026, 30-day mortality was 25.9% versus 20.5% with prehospital whole blood versus components; adjusted OR 1.24, 95% CI 0.87 to 1.76; P=0.24. 14
    • Neither demonstrated superiority for its primary endpoint. These trials inform product choice before hospital arrival; they neither replicate PROPPR’s component-ratio comparison nor establish whole blood and 1:1:1 components as interchangeable treatments.

Summary

  • PROPPR randomised 680 severely injured patients predicted to require massive transfusion to early plasma:platelets:RBC ratios of 1:1:1 or 1:1:2.
  • Neither 24-hour mortality, 12.7% versus 17.0%, nor 30-day mortality, 22.4% versus 26.1%, demonstrated statistically significant superiority; clinically important benefit remains possible.
  • More patients achieved haemostasis and fewer died from exsanguination by 24 hours with 1:1:1, but these were exploratory findings and haemostasis was not demonstrably faster.
  • 1:1:1 increased plasma and platelet exposure without reducing median RBC use; no complication difference was detected, with limited precision for uncommon harms.
  • The trial supports early balanced component delivery within a responsive haemorrhage protocol, while leaving uncertainty about the optimal ratio, the contribution of platelet timing and overall survival benefit.

Overall Takeaway

PROPPR is a landmark in the randomised evaluation of early trauma transfusion: it provided evidence of improved haemostatic outcomes with prompt 1:1:1 component delivery compared with 1:1:2, while leaving all-cause mortality superiority unresolved. Its practical contribution is support for early plasma and platelet availability, followed by treatment adapted to ongoing bleeding and coagulation findings.

Overall Summary

  • Primary outcomes: No demonstrated superiority of 1:1:1 for 24-hour or 30-day all-cause mortality.
  • Potential benefit: More patients achieved haemostasis and fewer died from early exsanguination; these exploratory findings favour 1:1:1.
  • Clinical implication: Deliver haemostatic components early, secure bleeding control and reassess; PROPPR does not establish a universally superior fixed ratio.

Bibliography

Last updated September 10th, 2026