Seven Ss of Single Sedan Smashes

Your partner and you are sent to an MVA at I-6 south of U.S. 185.  When you arrive, you find a newish Ford Explorer that crashed into the right side wire barrier, taking out four or five of the metal posts.  The impact seems to have snagged the left front of the SUV and spun it to face oncoming traffic.  There is about a foot of left front damage, and sheet metal flexing means that the driver’s door won’t easily open.  The airbags deployed, but the windshield, steering wheel, and dash are all intact.  None of the damage extends into the passenger compartment.

The only occupant is the 60-year old female driver.  She was seatbelted and has no complaints.  Your detailed physical examination yields no indication of injury.  The driver is oriented, with decision-making capacity, but she doesn’t remember what caused the accident.  She states that she remembers leaving lunch with a friend and remembers facing the wrong way on the highway with steam coming out of her crunched up hood.  There is nothing in between those two memories, though.

Why did she crash?

There are “Seven Reasons for Single Sedan Smashes” that you need to know.  In reality, however, there are Ten Reasons for Single Vehicle Crashes.  (The ‘seven’ is alliteration with sedan and smash. We’re really talking about the ten reasons that single vehicle MVAs occur, but all the S-words makes it sound all snazzy.)  People don’t bend their vehicles into an immobile object very often.  Most crashes involve two vehicles trying to occupy the same space at the same time.  People expect the other driver to wait, or to not stop, or whatever, and it causes a crash.  I mean, you’ve met your average patient, right?  Or the jackhole in front of you during rush hour?  Consider that they are [reportedly] in control of two tons of vehicle at seventy miles an hour.  It shocks me that we aren’t running more crashes, if I’m being honest. 

But single car crashes are slightly weird.  People really shouldn’t be driving into trees.  Trees don’t suddenly jump into their path. 

Dude! Why did you crash? Are you hypoglycemic?!?
(By Bo Nash [CC-BY-SA-2.0], via Wikimedia Commons)

The ten reasons for single vehicle MVAs are seizure, syncope, sudden cardiac arrest, stroke, sugar, sleep, sauce, suicide, shit happens, and stupidity.  Pretty much every reason for a single vehicle grinder is contained in these ten reasons.  The trick is to understand that #10 (stupidity) is the diagnosis of exclusion.  You need to rule out, as much as you can, the other reasons for bending a vehicle around an immobile object before you roll your eyes at your patient’s lack of driving ability. 

In more detail…

1. Seizure – People have seizures.  Sometimes those seizures can occur when they are driving.  This is especially true for first-time seizures because people don’t know what that “orange smell” portends.  So they seize and the car goes where it will.  Hopefully you can identify a postictal patient enough to be suspicious of the seizure being a potential cause of the accident. 

2. Syncope – This is pretty much a big-tent kind of point.  There are hundreds of events and conditions that can cause syncope.  For our purposes, though, we are worried about arrhythmias, vagal episodes, situational syncope, occult bleeding resulting in hypotension, and such things.  These are the same big-deal reasons for syncope that you work up when you run a fainting patient.  Prodromal symptoms should be part of the pre-crash story.

3. Sudden Cardiac Arrest – The most common reason for me to suspect sudden arrest is finding a dead guy in a crash that really shouldn’t have killed him.  The vehicle has a bent license plate, but there is a corpse in the driver’s seat without a scratch on him.  In these cases, even though it is a “trauma” call, I work the arrest like a medical arrest.  If you suspect that trauma didn’t cause the arrest, then a medical event probably did.  Work the medical arrest in those cases.

4. Stroke – It sucks to have a stroke, but it sucks even more to have one happen at highway speeds. 

5. Sugar – It sucks to be hypoglycemic, but it sucks even more to have it happen at highway speeds.  By the way, the crash won’t correct their blood sugar levels.  Their sugar will still be low, they will be tachy and diaphoretic, and they will still have all the other signs of hypoglycemia after the crash. 

6. Sleep – People fall asleep behind the wheel.  They take long trips on boring highways at night.  They also take an Ambien and misjudge how long until it takes effect.  Whatever the cause, sleep can cause a crash.  This is more likely at night, of course, or if the driver describes a fatiguing trip (long haul trucker, maybe, or a long ass drive in general).

7. Sauce – I am talking about alcohol intoxication of course, but you should also think about any other consciousness-altering substance or medication.  There are a bunch of analgesics, sedative/hypnotics, anxiolytics, and miscellaneous psychiatric medications that affect driving ability.  But for the most part, alcohol is the big one.  Single car crashes result in DUIs all the time, right?  Drunk people drive into stuff.  But you should be able to pick up on the signs of acute intoxication.

8. Suicide – I once saw a guy that unbuckled his seatbelt, balanced a tire iron on the steering wheel pointed at his chest, and floored it into a concrete wall.  Suicide.  (That guy made a poor choice, based on the fact that his last words were to me when I walked up to his window: “This hurts man.”)  Other people steer into oncoming traffic*.  Thelma and Louise drove off a cliff.  Suicide in a car happens.

9. Shit Happens – Sometimes the insurance term “act of god” makes sense.  Consider the family that had a i-beam bridge girder fall on their car without warning.  Or a rock that falls out of the truck in front of a dude, who then stops the rock entirely too suddenly.  Freak accidents look like freak accidents, though.  Freak accidents don’t look like a person drove into the guardrail a little.  Freak accidents kind of scare you about your own mortality.

10. Stupid – See my point above about your average patient being in sort-of-control of two tons of mobile steel.  This is the diagnosis of exclusion, but it is probably the most common reason for single car MVAs.  People text and drive.  They get CDs off the passenger floor while driving (maybe not nowadays, but when I started in EMS they did that kind of thing).  They put on make up and eat greasy burgers while driving in the snow.  Hell, admit it – you do these things, probably while driving emergently.  I once was off-duty and cruising at 70 miles per hour on a dry highway when I found an elk in my headlights.  My gentle course correction to avoid smashing the stupid thing caused me to do a 360.  On dry highway.  At 70.  Thankfully I didn’t roll it, but I had to rock when I got out of my truck to break the suction.  Stupid things happen and cause single car crashes. 

I saw a teenager who crashed into a tree when avoiding a raccoon. Which is good, because I love this picture and it gives me the excuse to use it. Look at that bastard in front. It just puts a smile on my face...
(Photo courtesy Jeremy Johnson, Meddling with Nature)

Just make sure one of the other nine didn’t cause the crash before you blame it on “Stupid.”  The same goes for the shit happens point.  If you find one of the other weird reasons, you get to look like a badass.  Another problem is that many of the causes will have presentations that mimic head injury or other traumatic injury.  It is pretty difficult to differentiate whether a seizure caused the crash or was the result of the crash, for example.  Just do your best. 

Remember to think through the ten reasons for single car crashes.

Oh, and the lady in the introductory scenario?  I couldn’t figure out what caused the crash.  So I picked at it.  I wouldn’t let it go.  After digging and digging, she told me that she was narcoleptic.  But she hadn’t had an episode in years.  Granted, she ran out of her Provigil two or three days ago, but that shouldn’t mean anything.  Right?

*Not a single car crash then, I know.  Just roll with the point I’m trying to make.