BACKGROUND: Reliance on prehospital trauma triage guidelines misses patients with serious injury. Lactate is a biomarker capable of identifying high-risk trauma patients. Our objective was to compare prehospital point-of-care lactate (P-LAC) with systolic blood pressure (SBP) for predicting the need for resuscitative care (RC) in trauma patients transported by ground emergency medical services. METHODS: This is a prospective observational study at nine sites within the Resuscitation Outcomes Consortium conducted from March 2011 to August 2012. Lactate was measured on patients with a prehospital SBP of 100 mm Hg or less who were transported by emergency medical services to a Level I or II trauma center. Patients were followed up for the need for RC, defined as any of the following within 6 hours of emergency department arrival: blood transfusion of 5 U or greater; intervention for hemorrhage including thoracotomy, laparotomy, pelvic fixation, or interventional radiology embolization; or death. RESULTS: A total of 387 patients had a lactate value and presented with SBP between 71 mm Hg and 100 mm Hg, and 70 (18%) required RC. With the use of a P-LAC decision rule (≥2.5 mmol/L) that yielded the same specificity as that of SBP of 90 mm Hg or less (48%), the observed sensitivities for RC were 93% (95% confidence interval [CI], 84-98%) for P-LAC of 2.5 mmol/L or greater and 67% (95% CI, 55-78%) for SBP of 90 mm Hg or less (McNemars test, p < 0.001). P-LAC has an estimated area under the curve of 0.78 (95% CI, 0.73-0.83), which is statistically superior to that of SBP (0.59; 95% CI, 0.53-0.66) and shock index (heart rate / SBP) (0.66; 95% CI, 0.60-0.74). CONCLUSION: P-LAC obtained at the scene is associated with the need for RC. P-LAC is superior to other early surrogates for hypoperfusion (SBP and shock index) in predicting the need for RC in trauma patients with 70 mm Hg < SBP ≤ 100 mm Hg. LEVEL OF EVIDENCE: Prognostic study, level II.

Background

The Pragmatic Randomized Optimal Platelet and Plasma Ratios (PROPPR) study evaluated the effects of plasma and platelets on hemostasis and mortality after hemorrhage. The pulmonary consequences of resuscitation strategies that mimic whole blood, remain unknown.

Methods

A secondary analysis of the PROPPR study was performed. Injured patients predicted to receive a massive transfusion were randomized to 1:1:1 versus 1:1:2 plasma-platelet-red blood cell ratios at 12 Level I North American trauma centers. Patients with survival >24 h, an intensive care unit (ICU) stay, and a recorded PaO2/FiO2 (P/F) ratio were included. Acute respiratory distress syndrome (ARDS) was defined as a P/F ratio < 200, with bilateral pulmonary infiltrates, and adjudicated by investigators.

Results

Four hundred fifty-four patients were reviewed (230 received 1:1:1, 224 1:1:2). Age, sex, injury mechanism, and regional abbreviated injury scale (AIS) scores did not differ between cohorts. Tidal volume, positive end-expiratory pressure, and lowest P/F ratio did not differ. No significant differences in ARDS rates (14.8% vs. 18.4%), ventilator-free (24 vs. 24) or ICU-free days (17.5 vs. 18), hospital length of stay (22 days vs. 18 days), or 30-day mortality were found (28% vs. 28%). ARDS was associated with blunt injury (OR 3.61 [1.53-8.81] P < 0.01) and increasing chest AIS (OR 1.40 [1.15-1.71] P < 0.01). Each 500 mL of crystalloid infused during hours 0 to 6 was associated with a 9% increase in the rate of ARDS (OR 1.09 [1.04-1.14] P < 0.01). Blood given at 0 to 6 or 7 to 24 h were not risk factors for lung injury.

Conclusion

Acute crystalloid exposure, but not blood products, is a potentially modifiable risk factor for the prevention of ARDS following hemorrhage.