Background

Prior to this study, the preoperative approach to hypotensive patients with trauma included prompt intravenous infusion of isotonic fluids – the rationale being to sustain tissue perfusion and vital organ function while diagnostic and therapeutic procedures were underway. This was based on animal studies in the 1950s that demonstrated isotonic-fluid resuscitation was an essential component of therapy for severe hypotension due to hemorrhage.  The other side of the argument was that aggressive administration of fluids may disrupt thrombus formation, increase bleeding, and thus decrease survival.

Clinical Question

Does delaying fluid resuscitation until the time of operative intervention improve survival in hypotensive patients with penetrating injuries to the torso?

Population

Adults or adolescents (>16 y/o) with a penetrating torso injury (as defined superiorly by the upper end of the neck, anteroinferiorly by the inguinal ligaments and symphysis pubis, and posteroinferiorly by the gluteal folds) and a systolic blood pressure <90 mmHg at the time of initial on-scene assessment by paramedics from the City of Houston Emergency Medical Services system.

Intervention

Delayed Resuscitation Group: Standard paramedical protocol that included endotracheal intubation and assisted ventilation with oxygen when appropriate, rapid transport to emergency center, and insertion of two or more 14G IVs in the upper extremities. After insertion of PIVs, lines were flushed with 1-2 cc of heparin and capped. Any additional P/CVLs that were placed in the ED were kept patent with infusion of 10 cc/hr.

Control

Immediate Resuscitation Group: Same as above except after insertion of two or more 14G IVs in the UEs, there was immediate rapid infusion of isotonic crystalloid (Ringers Acetate).

Outcomes

  • Primary: Survival and discharge from hospital
  • Secondary: Complications rates as defined as: ARDS, Sepsis, Acute Renal Failure, Coagulopathy, Wound Infection, Pneumonia

Design

Prospective, unblinded trial with groups assigned according to 24-hour period in which they presented, alternating every 24 hours.

Excluded

  • Pregnant women
  • Those with a fatal gunshot wound to the head
  • Patients with minor injuries not requiring operative intervention

Primary Results

Primary Results

  • 1069 consecutive patients with hypotension and penetrating torso injuries
    • 598 patients remained based on inclusion criteria
      • 309 Immediate Resuscitation
      • 289 Delayed Resuscitation
    • Of the 598 patients, 70 died before reaching the OR, 528 reached the OR
      • 268 Immediate Resuscitation
      • 260 Delayed Resuscitation
    • Fluid Resuscitation in the Immediate vs. Delayed Group
      • Average Volume of Ringers Acetate Infused in the Pre-Hospital Phase
        • 870 cc vs 92 cc
      • Average Volume of Fluids Infused in the Trauma Center
        • 1,608 cc vs 283 cc
      • In the OR, there were no significant differences in the volume of IVF, pRBCs, FFP, platelets, and autologous blood transfusions administered.

Critical Findings

  • On arrival to the OR, groups were not statistically different in terms of SBP, pH, and bicarbonate. However, the immediate resuscitation group had a statistically significant lower hemoglobin (11.2 vs 12.9 g/dl)
  • Primary: Overall rate of survival was significantly higher in the delayed-resuscitation group that in the immediate-resuscitation group: 70% vs. 62% (p = 0.04)
  • Secondary: There was a trend towards more complications in the immediate-resuscitation group (30% vs 23%), which was not significant.
    • Complications defined as: ARDS, Sepsis, Acute Renal Failure, Coagulopathy, Wound Infection, Pneumonia
    • Duration of hospitalization was shorter in the delayed-resuscitation group.

Strengths

  • Study asked a simple, clinically relevant question with a patient centered-outcome
  • Relatively large sample size given the nature of the pathology
  • Study was in a setting with a single centralized system of pre-hospital emergency care and a single receiving facility for patients with major trauma

Limitations

  • Given the nature of the study, formal randomization procedures were not logistically feasible.
  • Study was conducted at a single urban hospital, thus limiting generalizability

Author's Conclusions

“Our study shows that aggressive administration of intravenous fluids to hypotensive patients with penetrating injuries to the torso should be delayed until the time of operative intervention”

Our Conclusions

In this single-center study, delayed fluid administration was associated with improved survival in hypotensive patients with penetrating injuries to the torso requiring operative intervention.

Potential Impact To Current Practice

Based on the data, limiting fluid resuscitation in hypotensive patients with penetrating injuries to the torso until the operative room, should be considered.

Bottom Line

While delaying fluid resuscitation in trauma patients requiring operative intervention may improve outcomes, the assumption should not be made that crystalloid administration alone, in traumatic settings, worsens hemorrhage and coagulopathy. Greenfield et al demonstrated that in healthy, non-bleeding subjects, crystalloid administration alone causes significant (though transient) decreases in hematocrit.

Read More

REBEL EM: Ten (Trauma Resuscitation) Commandments

Greenfield RH, Bessen HA, Henneman PL. Effect of crystalloid infusion on hematocrit and intravascular volume in healthy, nonbleeding subjects. Ann Emerg Med. 1989;18(1):51-5. PMID: 2910162