Eye injuries: From “No big deal” to “HOLY S*%T” Part 2

After years of scraping accidents off highways, there’s not much that skeeves me out any more.  There are a few exceptions: Beer vomit, stringy snot, snaggleteeth, and eye injuries.  Just in case you’re of a like mind, here’s your warning:  Gross pictures ahead.

What better time to explore the “HOLY S*%T” side of eye injuries than with the news that Manny Malhotra has been cleared to play just in time for the Stanley Cup finals.  The exact nature of his eye injury was never made clear, but he’s undergone two eye surgeries since the injury on March 16th, and may require a third in the offseason.  He’s also made it clear that he’s changed his view on the subject of vision protection:

“I realize the importance of it now,” he said. “I’ll wear the full face shield for the rest of this year and see what my comfort level is with different pieces of equipment.”

Manny Malhotra, eye surgery expert.

Having already looked at injuries to the surface of the eye, it’s time to look at their more serious, grosser cousins – blunt and penetrating eye injuries.

What’s in there?

There's a lot crammed into a little space

First, the contents of the eye.  At the front is the cornea, the clear covering that gets scratched when you don’t take care of your contacts properly (and you can get eye fungus, so don’t do that, okay?).  The iris is the coloured part of your eye, the pupil is the black bit in the middle (and isn’t really a thing per se – more like a hole), and the lens is the lens (duh) which focuses light (and thus images) on your retina.  The retina lines the inside of the eye and translates what you’re seeing into information your optic nerve takes to your brain.  The macula is a little spot near the center of the retina that’s responsible for central high-definition vision.

The largest part of the eye (the posterior chamber)  is filled with vitreous humour, a thick jelly-like material that helps the eye maintain its shape.  The front of the eye (the anterior chamber) – the space between the cornea and the lens – is filled with aqueous humour, a less viscous liquid that also serves in a shape-maintaining capacity.  Aqueous humour is constantly being produced in the eye and draining out via the vasculature.  Vitreous humour is a little more boring, pretty much just sitting there.

How much blood can the eye hold, anyway?

Like most things in your head, the eye is plenty vascular.  Also like the head, it’s basically a closed system.  The upshot?  If something in your eye is bleeding, there’s not really much of anywhere for the blood to go.  Let’s assume you’ve taken a puck in the eye, and the impact has torn a blood vessel in the anterior chamber.  You’re likely to end up with a hyphema – the fancy word for an anterior chamber full of blood.

Hyphema - Blood in the anterior chamber.

Hyphema can cause pain, light sensitivity, and vision disturbances.  The treatment depends on how severe it is.  A mild injury may heal on its own with rest, an eye patch (to protect the eye and make you look like a cool pirate), sleeping with your head elevated, and painkillers.  A serious injury can cause a rise in the intraocular pressure either by occupying space with blood, or through inflammation to the area where the aqueous humour drains.  Either way this is an emergency, and may require surgery to drain the blood out of the eye.

Careful, you’ll detach your retina!

Since the retina’s job is to receive the input from the lens and pass it along to the optic nerve, it stands to reason that it’s absolutely packed with nerve tissue.  Nerve tissue needs a blood supply to stay alive, and the blood supply comes from the back of the eye.  So it’s not hard to understand why a detached retina is an emergency – if the retina isn’t attached to the back of the eye, it’s not getting the blood supply it needs, and nerves will die (translation: vision loss).

A blow to the eye will briefly change its shape.  Remember the eye is filled with vitreous humour, which is attached to the retina at the optic disc (the area where the optic nerve enters and exits the eye).  If you change the shape of the eye, you’ll move the vitreous around, and this can result in traction on the retina.  The retina is thin and delicate, and traction will tear it.  It can also tear at sites of direct impact on the surface of the eye.  A retinal tear is bad enough, but when you add the fact that the vitreous takes advantage and starts seeping in between the retina and the back of the eye, you’ve got a serious problem.

This is bad news.

 

Retinal detachment comes with a scary set of symptoms – floaters, flashers (those are self-explanatory), shadows in the peripheral vision, and sudden vision loss.  Treatment is surgical – draining the fluid out from behind the retina, and attaching it back to the inside of the eye.  This can be done by laser (scarring the retina in place), freezing (same idea), instilling a gas bubble that sits over the tear (but the patient has to stay in a certain position – usually face down – for up to two weeks), or a vitrectomy – where the vitreous is actually removed from the eye and replaced by gas or silicone oil.  Gas will eventually be replaced by new vitreous, but oil must be removed with a later surgery.  Retinal detachment surgery has very high success rates – some sources quote numbers as high as 90%, although often requiring more than one procedure.

 

It’s all fun and games until…  You know.

One of the most obvious and impressive eye injuries is a ruptured globe.  That’s exactly what you think it is – a popped eyeball.  It’s not hard to figure out the mechanics between blunt or penetrating trauma and a ruptured eye.

 

Ruptured globe

 

Ruptured globes cause pain (obviously), vision disturbance (obviously), and may result in permanent vision loss (again, obviously).  The treatment is immediate surgery, assuming the eye can be saved.  The surgery is pretty straightforward – the patient gets a crapload of antibiotics, is anesthetized, and the holes in the eye are sewn shut after any foreign bodies are removed.  That’s a pretty heinous oversimplification, but the details of suture size and how you close each layer aren’t very exciting.  An injection of salt solution into the eye both restores the shape of the eye and tests whether the repair is waterproof.  More antibiotics are injected under the conjunctiva (the white of the eye), and the patient gets yet more antibiotics (topical and IV) as well as topical steroids.  Globe ruptures often go hand-in-hand with retinal detachment – either when the injury occurs or later on as vitreous sneaks under the retina.

 

The moral of the story…

It’s certainly possible to regain full vision after an injury like these, but of course it’s entirely dependent on the nature of the injury, how quickly it was repaired, and plenty of other factors.

Wouldn’t you rather get a Stamkos-esque nose laceration than a Malhotra or Berard-esque eye injury?  As we learned in an earlier post, visor use may result in facial lacerations of greater severity, but overall results in decreased injury to the face.  The simple truth is that while I’m pretty fantastic at sewing up your face, I’m not very good at fixing your eye.  You can guarantee that any NHL game will have a doctor on site who can stitch up your face.  There may or may not be an opthalmologist on staff, but the odds of a fully functional opthalmologically-outfitted OR are firmly parked at zero.  Your face can be repaired.  Your eyes?  Maybe.  Maybe not.  Hell of a chance to take.

 

- Jo

 

 

 

Of OxyContin and Alcohol

I was boredly scrolling through my Twitter feed this afternoon when this caught my eye:

The part about not mixing OxyContin and alcohol is absolutely right.  The part about how people with head injuries should never use it?  Not quite.  First of all, there’s a difference between an acute head injury and a concussion five months ago.  But I’m getting ahead of myself.  This was next:

What’s that link?  Why, it’s the oh-so-reputable Canoe.ca drug fact sheet!  And here’s what the renowned world experts at Canoe.ca had to say that apparently caught Steve’s eye:

Oxycodone should not be taken by anyone who:

- blah blah blah

- has a head injury

- blah blah blah

And then I think he stopped reading.  Yes, Derek Boogaard sustained a concussion on December 9th of last year.  No, the mix of taking oxycodone after having had a concussion five months ago didn’t cause his death.  What caused his death was a mixture of oxycodone and alcohol.

What is OxyContin?

OxyContin is the trade name for oxycodone, which is a synthetic opiate.

What are opiates?

You’ll often hear the terms opiate and opioid used interchangeably.  Technically opiates are natural derivatives of a certain type of poppy, and opioids are the class of drug that binds the opioid receptors in the body.  So opioids as a whole include the opiates (morphine, opium) and the synthetic and semi-synthetic derivatives (oxycodone, fentanyl, methadone, heroin).

What do they do?

Opioids bind to the opioid receptors, which are found in the nervous and GI systems.  These drugs are used for pain relief, cough suppression, diarrhea, sedation and to ease withdrawal from other drugs in the same class.

What’s the big deal?

Opioids have a lot of side effects – sedation, constipation, itching, etc.  Unfortunately, they also have a nasty habit of causing respiratory depression in larger doses or extremely potent forms.  Also unfortunately, someone who has been using opioids for a long time will establish a tolerance, meaning they require higher and higher doses to achieve the same effects.

Where do head injuries fit into this?

In Derek Boogaard’s case, they don’t.  He had a concussion five months ago – he was not dealing with an acute head injury.  The reason “head injured” people shouldn’t have opioids has to do with intracranial pressure (ICP), the potential for respiratory depression with these drugs, and the nasty connection between the two.  The reason I have “head injured” in quotes?  Because we’re talking about people with acute injuries.  Those are the people that will have increased ICP.  Remember there’s a finite amount of space in your head.  If your brain is injured it swells, and since there’s not much of anywhere to go, you get an increase in the pressure inside your skull.

Now remember back to middle school science.  When you breathe, you exchange carbon dioxide for oxygen.  So if you’re taking opioids to the point that you’ve depressed your respiratory drive, you won’t be exchanging gases adequately and you’ll have increased levels of carbon dioxide.

Still with me?

We’re moving on to bigger and badasser science.  Carbon dioxide causes vasodilation in the cerebral vasculature.  Put simply – too much CO2 causes the blood vessels in your brain to dilate.  If you’re head injured and already have or are at risk for increased ICP, the last thing you need is increased CO2.  You’ll have bigger vessels, which means more blood, which means more space occupied, which means even higher pressure.  You’ll be making a bad situation worse and risking your brain trying to find a pressure release, which involves trying to squeeze its way out of the bottom of your skull.  That’s called herniation, and that’s generally deadly.

Summarized:

- Head injury = increased pressure in your head (from bleeding or swelling).

- Lots of opioids = respiratory depression (shallow/slow breathing, or no breathing).

- Respiratory depression = too much CO2

- Too much CO2 = more pressure in your head.

- Not good.

The Boogaard connection

Derek Boogaard’s cause of death was said to be a mixture of alcohol and oxycodone.  There’s not a huge amount of research on the pharmacology/pathophysiology of mixing alcohol and opioids, but they’re both depressant medications and together they’re dangerous.  Some studies suggest that alcohol alters opioid metabolism, resulting in an effectively higher serum concentration, and thus greater effects.  Common sense suggests that if you take two substances that can knock you out, one of which can make you stop breathing, that you’ve got all the ingredients for a terrible outcome.

From a paramedic’s perspective:

Over the years I’ve seen a lot of overdoses that resulted in death.  Most of them were opioid overdoses, and very, very few of them were on purpose.  Heroin addicts with the needle still in their arm,  college kids that got hammered and took too many pills, chronic pain patients with a huge opioid tolerance that fell asleep and never woke up.  People on the street, people in million dollar houses, and people just like you and me.

Before we start judging Derek, we need to stop and realize just how easy (and common) this situation is.  We know he was trying to get help.  We also know from his family’s statement that he’d been dealing with pain for a very long time.  The suggestion that taking oxycodone five months after his concussion was what caused his death minimizes his struggle, and isn’t scientifically based in reality.

Derek Boogaard’s family has asked that donations be made to Defending The Blue Line, a Minnesota charity that helps military kids stay involved in hockey with equipment donations, camps, and grants to cover fees.  Donations may be made online or by mail:

Defending the Blue Line,

c/o Boogaard’s Booguardians Memorial Fund,

1206 N. Frontage Road Suite B, Hastings, MN 55033.

My heart aches for the Boogaard family.  All the best to them.

- Jo

Phaneuf v Moser, aka What Not To Do With An Unconscious Guy

Video of Dion Phaneuf’s hit on Simon Moser at a Canada/Switzerland match at the IIHF worlds is making the rounds today. Phaneuf delivers a solid hit, Moser gets up. Once on the bench, Moser passes out, and Hockey Expressen says it was because he “swallowed his tongue”.

STOP.

That doesn’t exist. Some freaky people can do freaky things that involve freaky tongue gymnastics. Granted. In this case, however, what the video shows is poor management of an unconscious patient. Let’s watch, shall we?

What do you notice there? An unconscious guy that some dude is holding upright while his head flops back. That makes my inner paramedic cringe in horror. While you can’t technically swallow your tongue, it can block the hell out of your airway. Especially if some Swiss dude is holding you upright while you’re unconscious. The thing about unconscious people is they can’t do a little thing we like to call “protecting your own airway”. ie. keeping things out of there – your tongue, vomit, etc. In fact, the most common cause of airway obstruction in unconscious patients is the tongue. And here’s why:

Throat Anatomy

Your tongue is huge. When you’re unconscious, you’re not in control of voluntary muscles like the ones in your tongue and lower jaw. So if you’re upright, on your back – or in any position that lets gravity take over – your tongue is going to slide back and occlude your airway. You don’t swallow it. To wit:

Sneaky bugger.

So how do you keep this from happening? Well, if there’s no chance of a spinal injury, you’d roll them onto their side into something called the recovery position:

The right thing to do with an unconscious dude/dudette

The patient needs to be on their side, head extended, limbs positioned to keep them stable. The point of this is that the tongue won’t slide back, and vomit will drain out, not down. If there is a question of spinal injury, then someone will hold c-spine (a hand on either side of the head to maintain the head, neck and spine in a straight line) until the patient can be secured in full spinal precautions (which the Slovakian paramedics in the video have on their stretcher), and you can still roll them onto their side. Carefully.

So what should the Swiss trainer have done? Get Moser on the ground. You can pass out from trauma, or you can pass out from things that deprive your brain of adequate oxygen – things like hyperventilating, vagal nerve stimulation (remember Bush choking on a pretzel?), low blood pressure, and standing up too fast (ask any skinny girl about this). Moser was not immediately knocked out by the hit, so it’s possible one of these things took him out. Best way to get blood (and thus oxygen) to the brain? Get the brain on the same level as the heart and it won’t have to pump so hard. If the loss of consciousness was due to some kind of head pathology (like bleeding or concussion), lying him down is about 500% better than trying to haul him upright and letting his head flop around.

Take home points:

- Your tongue will block your airway given half a chance.

- Unconscious people can’t protect their airway.

- The recovery position is good.

- Protect the c-spine if there’s any question of injury.

- Slovakian paramedics have jazzy red jumpsuits and it takes four of them to run a call.

- Everyone should take CPR. Stat.

Jo

ps – the recovery position is also ideal for people who’ve passed out drunk. Nobody wants barf in their lungs. Scientific fact. Nobody.

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