From the Guidelines
Not all hypotensive trauma patients should receive intravenous (IV) fluids, and the approach should be individualized based on the type of trauma and hemodynamic status.
Key Considerations
- For penetrating trauma with hypotension, permissive hypotension is preferred with minimal or no fluid resuscitation until definitive hemorrhage control is achieved, targeting a systolic blood pressure of 80-90 mmHg, as supported by a recent meta-analysis of RCTs 1.
- For blunt trauma with hypotension, limited fluid resuscitation may be appropriate, aiming for a systolic blood pressure of 90-100 mmHg.
- When fluids are indicated, begin with 1-2 L of warmed isotonic crystalloids (normal saline or lactated Ringer's solution) given as 500 mL boluses with reassessment between boluses.
- Blood products should be prioritized for patients with ongoing hemorrhage, using a 1:1:1 ratio of packed red blood cells, plasma, and platelets, as this approach has been shown to reduce mortality in trauma patients without TBI and/or spinal injury 1.
Rationale
The concept of permissive hypotension and restrictive volume resuscitation is supported by several meta-analyses of retrospective studies, as well as combined prospective and retrospective studies, which have shown reduced mortality in comparison to traditional aggressive volume replacement targeting normotension 1. Excessive fluid administration before hemorrhage control can worsen outcomes by diluting clotting factors, disrupting forming clots, and causing hypothermia, as demonstrated by retrospective analyses of trauma patients 1.
Important Exceptions
The concept of permissive hypotension is contraindicated in patients with TBI and spinal injuries, as an adequate perfusion pressure is crucial to ensure tissue oxygenation of the injured central nervous system 1. In elderly patients, the concept of permissive hypotension should be carefully considered, and may be contraindicated if the patient suffers from chronic arterial hypertension 1.
From the Research
Trauma Patients with Hypotension and IV Fluids
- The administration of intravenous (IV) fluids to trauma patients with hypotension is a topic of ongoing debate in the medical community 2, 3, 4, 5, 6.
- Some studies suggest that a strategy of permissive hypotension, where IV fluid administration is restricted to allow for a reduced blood pressure, may be beneficial in reducing mortality and improving outcomes in trauma patients 2, 4, 6.
- However, other studies have found that the use of permissive hypotension may not be effective in all types of trauma, and that the optimal approach may depend on the specific characteristics of the patient and the injury 3, 5.
- A systematic review and meta-analysis found that there was no significant difference in mortality between patients who received standard resuscitation and those who received restricted resuscitation 4.
- State EMS protocols for fluid administration in hypotensive trauma patients vary widely, with different goals for systolic blood pressure, dosing strategies, and types of fluid used 5.
Permissive Hypotension vs. Fluid Therapy
- Permissive hypotension may have a positive impact on 30-day mortality compared to fluid resuscitation methods, particularly in patients with blunt force injuries 6.
- However, the effectiveness of permissive hypotension may depend on the type of injury, with some studies suggesting that it may be more effective for blunt force injuries than for penetrating injuries 3, 6.
- The use of permissive hypotension may also reduce treatment costs by reducing the volume of fluids used 6.
- Further research is needed to determine the optimal approach to fluid administration in trauma patients with hypotension, and to develop guidelines that take into account the specific characteristics of the patient and the injury 2, 3, 4, 5, 6.