Tag Archives: EMS

Air Embolism From an Intraosseous (IO) Line

IO lines are a godsend when we are faced with a patient who desperately needs access but has no veins. The tibia is generally easy to locate and the landmarks for insertion are straightforward. They are so easy to insert and use, we sometimes “set it and forget it”, in the words of infomercial guru Ron Popeil.

But complications are possible. The most common is an insertion “miss”, where the fluid then infuses into the knee joint or soft tissues of the leg. Problems can also arise when the tibia is fractured, leading to leakage into the soft tissues. Infection is extremely rare.

This photo shows the inferior vena cava of a patient with bilateral IO line insertions (black bubble at the top of the round IVC).

During transport, one line was inadvertently disconnected and probably entrained some air. There was no adverse clinical effect, but if the problem is not recognized and the line is not closed properly, there could be.

Bottom line: Treat an IO line as carefully as you would a regular IV. You can give anything through it that can be given via a regular IV: crystalloid, blood, drugs. And even air, so be careful!

Uber / Lyft For Medical Transport???

In this day and age of ride sharing apps like Uber and Lyft, it is possible to get a cheap ride virtually anywhere there is car service and a smart phone. And of course, some people have used these services for transportation to the hospital in lieu of an ambulance ride. What might the impact be of ride services on patient transport, for both patient and EMS?

A paper in preparation suggests that ambulance service calls decreased by 7% after the introduction of UberX rides. Now, there are a lot of questions here, because the full paper has not yet been peer reviewed, and the results write-up is pretty sketchy. But it does beg the question.

Ambulance rides are expensive. Depending on region, they may range from $500-$5000. And although insurance may reduce the out of pocket cost, it can still be expensive. So what are the pros vs the cons of using Uber or Lyft for medical transport?

Pros:

  • Ride shares are inexpensive compared to an ambulance ride
  • They may arrive more quickly because they tend to circulate around an area, as opposed to using a fixed base
  • Riders may select their preferred hospital without being overridden by EMS (although it may be an incorrect choice)
  • May reduce EMS usage for low acuity patients

Cons:

  • No professional medical care available during the ride
  • May end up being slower due to lack of lights and siren
  • Damage fees of $250+ for messing up the car

Bottom line: Uber and Lyft are just another version of the “arrival by private vehicle” paradigm. Use of these services relies on the customer/patient having very good judgment and insight into their medical conditions and care needs. And from personal experience, this is not always the case. I would not encourage the general public to use these services for medical transport, and neither do the companies themselves!

Reference: Did UberX Reduce Ambulance Volume? Unpublished paper, October 24, 2017.

Can Prehospital Providers Accurately Estimate Blood Loss? Part 2

I’ve previously written about the difficulties estimating how much blood is on the ground at the trauma scene. In general, EMS providers underestimated blood loss 87% of the time. The experience level of the medic was of no help, and the accuracy actually got worse with larger amounts of blood lost!

A group in Hong Kong developed a color coded chart (nomogram) to assist with estimation of blood loss at the scene. It translated the area of blood on a non-absorbent surface to the volume lost. A convenience study was designed to judge the accuracy that  could be achieved using the nomogram. Sixty one providers were selected, and estimated the size of four pools of blood, both before and after a 2 minute training session on the nomogram.

Here’s what it looks like:

Note the areas across the bottom. In addition to colored square areas, the orange block is a quick estimate of the size of a piece of paper (A4 size since they’re in Hong Kong!)

Here are the factoids:

  • The 61 subjects had an average of 3 years of experience
  • Four scenarios were presented to each: 180ml, 470ml, 940ml, and 1550ml. These did not correspond exactly to any of the color blocks.
  • Before nomogram use, underestimation of blood loss increased as the pool of blood was larger, similar to the previous study
  • There was a significant increase in accuracy for all 4 scenarios using the nomogram, and underestimation was significantly better for all but the 940ml group
  • Median percentage of error was 43% before nomogram training, vs only 23% after. This was highly significant.

Bottom line: This is a really cool idea, and can make estimation of field blood loss more accurate. All the medic needs to do is know the length of their shoe and the width of their hand in cm. They can then estimate the length and width of the pool of blood and refer to the chart . Extrapolation between colors is very simple, just look at the line. The only drawback I can see occurs when the blood is on an irregular or more absorbent surface (grass, inside of a car). 

Related posts:

Reference:  Improvement of blood loss volume estimation by paramedics using a pictorial nomogram: a developmental study. Injury article in press Oct 2017.

How Long Does It Take EMS To Respond?

How long does it take for EMS to get to the scene of an emergency? That’s a loaded question, because there are many, many factors that can impact this timing. If you look at the existing literature, there are few, if any, articles that have actually looked at this successfully.

A group from Aurora, IL and Wake Forest reviewed EMS records from across the country, spanning 485 agencies over a one year period. Only 911 responses were reviewed, and outliers with arrival times of more than 2 hours and transport times of 3 hours were excluded. Over 1.7 million records were analyzed, and 625 were excluded for this reason.

Here are the factoids:

  • In 71% of cases, the patient was transported to a hospital. In one quarter of cases, they were evaluated but not transported. 1% were dead on arrival, and in 2% no patient was found at the scene (!)
  • 4% of patients were transported in rural zip codes, 88% in suburban ones, and 8% from urban locations
  • Overall response time averaged 7 minutes
  • Median response times were 13 minutes for rural locations, and 6 minutes for both suburban and urban locations
  • Nearly 1 in 10 patients waited 30 minutes for EMS response in rural locations

Bottom line: There is an obvious difference in EMS response times between rural and urban/suburban locations. And there are many potential reasons for this, including a larger geographic area to be covered, volunteer vs paid squads, etc. Many of these factors are difficult, if not impossible to change. The simple fact that it takes longer to reach these patients increases their potential morbidity and mortality. Remember, time is of the essence in trauma. The patient is bleeding to death until proven otherwise. It is far easier and cost-effective to equip bystanders with the skills to assist those in need (basic first aid, CPR, Stop the Bleed, etc) while waiting for EMS to arrive.

EMS: Scoop and Run or Stay and Play for Trauma Care? The Final Answer?

I’ve been discussing the little research there is on stay and play vs scoop and run. And now, hot off the press, we have a paper about the ultimate version of scoop and run, the “drive-by ambulance.” This one looks at outcomes in patients who are dropped at the emergency department by private vehicle. This is the most basic form of prehospital care, with no interventions, just transportation. This type of transport is used by parents with their injured children, police who act as very basic first responders in some cities, and on occasion, gang members.

A multi-institutional group of authors used data in the National Trauma Databank to try to answer this question. They used three years worth of data, comparing outcomes from patients with ground EMS vs private transport who were treated at Level I and Level II trauma centers. Only gunshots and stabs were included, and all patients were 16 or older.  The  authors were focused on only one thing: mortality. This included death in the ED, and a model was developed to adjust risk based on vital signs, injury severity score (ISS), race, and insurance status. Just over 100,000 were included in he final analysis.

Here are the factoids:

  • Black and hispanic patients were more frequently transported by private vehicle, but only by about 3%
  • White patients were more frequently taken by ground EMS, by about 6%
  • Stabs were more likely to be brought by private car than gunshots, 56% vs 44%
  • Mean ISS was significantly higher for those transported by ground EMS (10 vs 5.5)
  • Unadjusted mortality was lower overall for private vehicle, 2% vs 12%
  • The chance of dying in the ED was also decreased in the private transport patients, from 7% to 1%
  • Mortality from both gunshots and stabs were also significantly lower (5% vs 9%, and 0.2% vs 3% respectively)
  • Once adjusted for risk, the lower mortality with private transport remained, with a 60% risk reduction of death. This persisted in the gunshot and stab cohorts as well.

Bottom line: Wow! Although this study has the usual limitations of using a large external database, it was very well designed to compensate for that. And the degree of improvement in survival is surprising. What this study can’t tell us is why. Certainly, some patients benefit from a little extra time to give fluid or blood, intubate, or provide some other treatments. But the patient with penetrating frequently does not need this, they just need definitive control of hemorrhage. The authors even go so far as to suggest that at-risk populations receive education on “scoop and run” if people they know suffer penetrating injury.

The next step is to tease out which components of the stay and play paradigm are the most valuable, and which contribute to the increased mortality in penetrating injury patients.

Reference: Association of Prehospital Mode of Transport With Mortality in Penetrating Trauma A Trauma System–Level Assessment of Private Vehicle Transportation vs Ground Emergency Medical Services. JAMA Surgery, Published online September 20, 2017.