Category Archives: Prehospital

Prehospital

Trauma Activation vs Stroke Code

Leave a comment

Let’s look at an uncommon scenario that crops up from time to time. Most seasoned trauma professionals have seen this one a time or two:

An elderly male is driving on a sunny afternoon, and crashes his car into a highway divider at  25 miles per hour. EMS responds and notes that he has a few facial lacerations, is awake but confused. They note some possible facial asymmetry  and perhaps a bit of upper extremity weakness. No medical history is available. Witnesses state that he was driving erratically before he crashed. Medics call the receiving trauma center in advance to advise them that they have a stroke code.

Is this a reasonable request? Stroke centers pride themselves on the speed of their stroke teams in assessing, scanning, and when appropriate, administering thrombolytics to resolve the problem. But if there are suspicions of stroke in a trauma patient, which diagnosis wins? Trauma team or stroke team?

Lets analyze this a bit further, starting with diagnosis. Remember the first law of trauma:

Any anomaly in your trauma patient is due to trauma, no matter how unlikely it may seem.

Could the symptoms that the paramedics are observing be due to the car crash? Absolutely! The patient could have a subdural or epidural hematoma that is compressing a cranial nerve. There might be a central cord injury causing the arm weakness. His TBI might be the source of his confusion. The facial asymmetry could be due to a pre-existing Bell’s palsy, or he could have had a stroke years ago from which he has only partially recovered.

If the stroke team is called for the patient, they will focus on the neuro exam and the brain. They will not think about trauma. They will follow the patient to CT scan looking for the thing that they do best with. If they don’t see it, the patient will return to the ED for (hopefully) a full trauma workup. If there are occult injuries in the abdomen, then the patient may have been bleeding for an hour by then. This elderly patient will then be way behind the eight ball.

And let me pose the worst case scenario. The patient is taken to CT by the stroke team, and lo and behold he has a thrombotic stroke!  This patient had a stroke, which caused him to lose control of his car and explains most of his findings. Again, the stroke team will do what they are trained to do and give a thrombolytic. They are still not thinking about trauma. Within minutes the patient becomes hypotensive and his abdomen appears a bit more distended. He is rushed back to the ED (remember, no CT in hypotensive patients even if you are in the scanner) and a FAST exam is very positive for free fluid throughout the abdomen. Imagine the look you will get from the surgeon as they run to the OR to perform a splenectomy on this fully anticoagulated patient!

Bottom line: If you have a patient who is trauma vs stroke, trauma always wins! Remember the first law and try to find traumatic reasons for all signs and symptoms. Perform your standard trauma workup and incorporate the appropriate head scans into your evaluation. Then and only then should the stroke team be called.

Print Friendly, PDF & Email
Prehospital, Resuscitation

Prehospital Use Of The ABC Score And MTP

Leave a comment

Early and appropriate resuscitation is critical in any severely injured trauma patient. Typically, the trauma team assesses the patient upon arrival and makes a determination as to what type of resuscitation fluids are most appropriate. If blood is judged to be necessary, individual units can be given, or the massive transfusion protocol (MTP) can be activated.

I’ve previously written about two objective methods to assist in the decision to activate your MTP, shock index (SI) and assessment for blood comsumption (ABC). These have traditionally been applied once the patient arrived. What would happen if you used prehospital information to calculate the ABC score and were able to activate your MTP sooner rather than later?

The group at the University of Colorado in Aurora studied this concept. The charge nurse captured information to calculate the ABC score from the initial prehospital information received by phone while the patient was enroute. He or she would then activate the MTP in order to have blood products delivered as close to patient arrival as possible.

They reviewed their experience over a 29-month period. The first 15 months used their original system, calculating ABC on arrival and then deciding whether to activate MTP. During the final 14 months, it was calculated prior to patient arrival and the MTP was “pre”-activated when the score was 2 or more. The primary outcome studied was mortality, and secondary variables were appropriate activation of MTP, and adherence to balanced resuscitation ratios.

Here are the factoids:

  • A total of 119 patients with hypotension and/or MTP activation were studied; 24 occurred pre-implementation and 95 post
  • Pre-implementation, 63% of 24 hypotensive patients had MTP activation and only 6 (40%) received blood. Only 2 patients (33%) had RBC:FFP ratios between 1:1 and 2:1.
  • Post-implementation, 98% of hypotensive patients had MTP activation, a 6-fold increase
  • Also post-implementation, 42% of the activations received the blood, and balanced product ratios increased to 77%
  • Overall mortality decreased from 42% to 19% after implementation, all of which occurred in the penetrating injury group
  • Hospital and ICU lengths of stay were unchanged and there were no readmissions

Bottom line: The authors actually rolled two studies into one here. The main focus of the paper was to look at use of ABC score using prehospital information, but they also changed their MTP setup at the same time. During the initial part of the study, they did not have thawed plasma available, so the first cooler contained only red cells. Plasma was delivered when available, usually about 45 minutes after the first cooler had arrived. Post-implementation, thawed plasma was included in the first cooler.

So is the reduction in mortality (only in penetrating injury) due to early availability of the entire cooler, or because the desired product ratios were much more consistently met? Unfortunately, we can’t know.

This is a relatively small study, but the results with respect to blood actually being given, attainment of ratios, and mortality are impressive. Is the takeaway message to activate MTP early based on prehospital info or to make sure all coolers stock plasma? My take is that it’s probably best to do both!

Related posts:

Reference: Effect of pre-hospital use of the assessment of blood consumption score and pre-thawed fresh frozen plasma on resuscitation and trauma mortality. JACS 228:141-147, 2019.

Print Friendly, PDF & Email
Abstracts, Prehospital

EAST 2019 #13: Geomapping Helicopter transports

Leave a comment

Helicopter EMS (HEMS) transports are a valuable yet very expensive resource. Unfortunately, many state trauma systems or local EMS agencies do not provide specific guidance for best use. A group at the University of Alabama in Birmingham performed a geospatial analysis of helicopter transports in their area to determine the efficiency of HEMS operations.

This group created a sort of “heat map” that showed the number of transports overlaid on a geographical map of their catchment area. It included HEMS transports over a 6-year period directly from the scene. Drive and flight times were calculated, and the latter also included flight time to reach the scene.


Here’s the heat map showing the entire state of Alabama. The approximate location of Birmingham is indicated in yellow.

Here are the factoids:

  • Nearly 3000 patients were identified, and 1911 had scene locations recorded so analysis could be performed
  • 35% of patients had minor injuries with ISS 1-8 (!!)
  • Median flight time was 58 minutes, and median drive time was only 65 minutes
  • In 28% of cases, drive time would have been shorter than flight time when considering time for the helicopter to reach the scene
  • Conclusion: over one fourth of patients might have arrived at the hospital more quickly by ground ambulance

Here are some questions for the authors and presenter to consider in advance to help them prepare for audience questions:

  • Why include time for the helicopter to reach the scene but not a ground ambulance? Doesn’t this stack the deck in favor of ground transport?
  • Was there any correlation between scene proximity and high ISS? This might have been a reason for calling the helicopter.
  • Did you see any patterns in the low ISS group? This could provide insight into the EMS thought processes. These patients are potentially the low hanging fruit to direct educational activities to reduce HEMS use.

This is thought-provoking work and I look forward to hearing all the details!

Reference: Use of helicopters for retrieval of trauma patients: a geospatial analysis. EAST 2019, Quick Shot Paper #26.

Print Friendly, PDF & Email
Prehospital

Best of AAST #4: Better Triage For Scene Helicopter Transport

Leave a comment
There has been tremendous debate around the value and use of prehospital helicopter emergency medical services (HEMS). It’s fast, but also expensive, and there is always a small amount of added risk to patients during transport. Over the years, there has been a significant increase in the number of helicopter services, and in some cases it seems like several services are dashing to accident scenes in the hope that they can pick up the patient.

Overuse of HEMS has also been recognized, with some patients transported who could have just as easily and safely been moved by ground ambulance. This is a particularly vexing problem with pediatric patients.

The holy grail of trauma HEMS has been to find some easy to identify scene variables that reliably predict which patients should be transported by air. A group in North Carolina tapped the state trauma registry to attempt to develop such a system. They analyzed data in the registry over a three year period, mathematically analyzing for easily identified predictors of ED death or need for operating room, interventional radiology, or ICU admission.

Here are the factoids:

  • The percentage of flights from the scene increased from 7% to 9% compared to data from fifteen years prior to this study
  • Vital signs (SBP, pulse, GCS motor) had the best correlation with mortality, and these were used to develop a regression model for triage
  • Patients with normal SBP, pulse, and GCS motor of 6 were found to safely transported by ground EMS, with similarly low mortality for ground or air
  • During the study period, triaging patients that met these criteria would have saved the state system about $19 million

Bottom line: Every state should take a look at their guidelines for helicopter vs ground transport for scene runs. This is an expensive tool, and should be treated with respect. Just because a helicopter is available does not mean it should be used. The commander on the scene must make the proper decision based on variables like these, but also apply their knowledge of traffic patterns, time and distance from the most appropriate receiving trauma center.

Reference: Trauma system resource preservation: a simple scene triage tool can reduce helicopter emergency medical services (HEMS) over-utilization in a state trauma system. Session IV Paper 13, AAST 2018.

Print Friendly, PDF & Email