Prehospital ultrasound: making our differentials more exact
Prehospital ultrasound pilot programs remain in their infancy at this time, but have shown increasingly good promise in recent years. We hope to highlight the effectiveness of this new tool, the boundaries to making it more available for EMS operational systems, the research behind it, and the enhanced view it can provide for some of our most critical patients in the field.
The case for ultrasound: field use
Prehospital ultrasound is currently used in two major categories: trauma FAST exams and the detection of cardiac motion/standstill in the case of cardiac arrest. Prehospital ultrasound currently shows the most promise in use for detecting internal bleeding in the case of acute abdominal or chest injuries.
As the EMS education platform emphasizes, the golden hour is the most critical aspect of trauma management. By limiting on scene time and initiating early transport, along with early activation of hospital trauma teams, EMS is able to save countless lives in the United States yearly. Maintaining this golden hour is the number one predictor of good patient outcomes in cases of severe trauma.
With prehospital ultrasound, clinicians are able to initiate transport without delay, begin their lifesaving treatments, start an activation, and then provide further detailed information to the hospital enroute. Clinicians can not only report their assessment findings, but are able to go deeper with prehospital ultrasound. Rather than stating that the mechanism of injury and clinical findings suggest a strong possibility for an internal bleed post-trauma, clinicians can provide field ultrasound exams to find the exact source and extent of internal trauma. With this valuable information, trauma teams can focus more on the ultimate definitive care at the operating table and minimize emergency room assessment times. A recent study found that case outcomes at the hospital were changed in 30 percent of cases utilizing prehospital FAST exams, with providers having a sensitivity of 93 percent and no false negatives. 22 percent of cases had their hospital transport decisions altered as a result of prehospital ultrasound findings, undoubtedly saving and reducing time to definitive treatment in the process.
In addition, prehospital ultrasound can be used for consideration of TOR in the case of cardiac arrest. Cardiac standstill can be confirmed in the field with objective, recordable findings rather than depending on vital sign output or time-based guidelines for terminating resuscitation. Additionally, prehospital providers can use the information gained to make transport decisions and identify potentially reversible causes of arrest.
Ultrasound can also be used to enhance skill use within the field. Ultrasound can notably be used for gaining IV access in patients with poor vascularity, performing needle-chest decompression, and confirming successful endotracheal tube placement.
Ultrasound training requires little time investment for great payoffs. With only a 6 hour training session, EMS providers can gain a valuable skillset that can be used to drastically improve interagency cooperation, identify high risk patients and conditions, and make valuable transport destination decisions without compromising other aspects of care.
Barriers to implementation
Cost remains the most important driving factor for prehospital adoption of ultrasound. However, as adoption and demand becomes more widespread, manufacturers are opting to reduce costs, find more efficient solutions, and even add in ultrasound capabilities to cardiac monitors.
Additional reading
Prognostic value of point-of-care ultrasound during cardiac arrest: a systematic review
SonoGuide: EMS Prehospital Ultrasound
Prehospital point-of-care ultrasound: A transformative technology
