A (nother) fantastic save! (long, a bit technical, surprise ending)

First of all, it’s fantastic to see James Hinchcliffe on the mend. As the story developed, we slowly were made aware of just how bad things had actually been. And now we’re told that he received 14 units of blood. This deserves some background, in order to fully understand just how well things worked for James . . . and draw some conclusions about how things are.

Even intuitively, hearing the number FOURTEEN PINTS is massive. Remember, James’ normal blood volume is probably (to simplify a bit) about 5 liters (for the english unit addicts, a quart is just about a liter). And a unit of red blood cells is about 400 ml. That means that his entire blood volume (5.6 liters to be exact) was replaced, presumably in the first 24 hours after admission. In trauma circles, that’s the standard definition of “massive transfusion”; this definition is not sterile, as it has important implications for management.

First, a few details.

Unlike what was headlined in some of the posts, the 14 units of blood were not administered BEFORE arriving at the hospital. There are several reasons for this (we will see the most medically relevant below), but the most practical is that this quantity of blood is NEVER available before getting to a hospital. The infield medical center at the IMS almost certainly has two to four units of blood (O negative, more later), but from there to the hospital, no blood would be available. More importantly, early transfusion of significant amounts of fluid are no longer standard protocol for massive bleeding.

The lovely tradition of drivers having their blood groups on their overalls is just that – a lovely tradition. No one, repeat NO ONE, will EVER EVER EVER be transfused based on some embroidered letters on his overalls. Ever. Period.

Let’s talk in some depth about just what and why the Holmatro team, and then the evac team who took James to the hospital did and didn’t do. First, some background.

Until very recently, the dogma in terms of taking care of trauma victims was to follow the “A B C” sequence. Life-threatening problems were dealt with in a very specific order. Problems with maintaining an open Airway were managed before problems with the Breathing, and only then were Circulatory derangements dealt with.

In terms of the circulation, by far the most common problem in trauma patients is hemorrhage. Blood loss causes a drop in the heart’s output, which in turn causes the various tissues of the body to be hypoperfused. This means that they receive too little oxygen and nutrients to maintain normal function. If this situation lasts, it is called hypovolemic (too little volume) shock. If this shock state lasts too long, it becomes irreversible; at that stage all attempts to save the patient are futile.

Advances in military medicine, notably during the Vietnam war, led to the idea of early and aggressive fluid replacement in shocked trauma patients. Intuitively this made perfect sense – since the primary problem was a deficit in circulating volume, restoring that volume (initially with relatively cheap and easy to store salt solutions) should allow cardiac output to trend upward, providing tissues with better nutritive perfusion.

This, in fact, is what is still taught in most mainstream trauma courses. After attending to the A and B parts of the protocol, we are told to rapidly begin infusing large quantities of fluid into shocked trauma victims.

The problem is, not only does this not work, but it actually makes things worse.

Huh?

Once again, some visionary physicians, working in almost war-zone conditions (ok, Houston, Texas to be exact), followed by the conflicts of the 2000s, have taken the received wisdom and turned it on its head.

First of all, the A B C sequence is being, slowly but surely, revised. It is clear that with certain injuries (think IEDs, think suspension elements ripping up a major artery in the thigh), massive arterial bleeding will kill a patient within scarce minutes, usually even faster than loss of airway opening. This has led some to propose a newer, more time-relevant acryonym: MARCH. This corresponds to Massive hemorrhage, Airway, Respiration, Circulation, Head injury.

Remember Alex Zanardi’s horrible accident in Lausitz in 2001? Well when i title this post “another”, that’s the other save to which I’m referring. Both in Germany (kudos again to Terry Trammell and Steve Olvey), and at Indy last month, the rescue teams concentrated basically all their efforts on what we call “exsanguinating hemorrhage” – commonly known as the patient bleeding out.

The second reversal of “standard” trauma care is rather less intuitive, but incredibly important.

While the idea of rapidly restoring a normal circulating volume (again, using clear fluids) would appear to make physiologic sense, studies done both in civilian penetrating trauma, as well as the military’s amazing database show that it is plain wrong (the lessons from this database will save tens of thousands of lives over the next decades; this being one of the most significant and lasting legacies of the conflicts in Iraq and Afghanistan).

When we look at two groups of trauma victims in hemorrhagic shock, one of which receives early and aggressive fluid resuscitation, while the other receives almost no fluid (UNTIL THE SURGEON HAS STOPPED THE BLEEDING, meaning that resuscitation is not ignored but delayed), we see a very significant difference in outcome. And surprisingly, it’s the group who is “allowed” to remain shocked (again, and crucially, until surgical bleeding control is obtained) who do considerably better.

Why would this be?

There are a number of hypotheses, all of which certainly contribute to the better outcome:

  • Restoring circulating volume with clear fluids does not contribute to the oxygen carrying capacity of blood, and, importantly, dilutes the clotting factors so vital to stem the bleeding by natural means
  • Increasing the blood pressure likely makes the tenuous blood clots that DO form less likely to stay in place, increasing bleeding
  • Even when using warmed fluids (and this can be quite hard to do, especially in the pre-hospital environment) massive infusion of clear fluids will usually make the patient hypothermic. The thing is, our coagulation system is exquisitely temperature sensitive. It begins to fail, miserably, when temperature gets below around 35°C, a temperature that is all too “normal” in shocked trauma patients.

Another crucially important element that has come from study of the military’s experience in recent conflicts has to do with not just WHEN we replace lost volume (as soon as surgical control is obtained), but WHAT we replace it with.

When a blood donor give a pint of blood, that pint is almost immediately fractionated. The red blood cells are packaged separately (this is the fraction most often needed by patients who are anemic from various causes), with the plasma (it’s here that we find most of the coagulation factors) and platelets (tiny cell fragments vital in the coagulation process) packaged separately.

Until recently, it was felt that shocked trauma patients mainly needed red blood cell transfusions; it was thought that the need for plasma and platelets was relatively rare. In fact, when I did my residency, we were taught specifically that plasma was NEVER to be used “simply” to restore circulating volume…ever.

Well once again, what seems clear and logical turns out to be wrong. In fact, hemorrhagic shock almost immediately induces problems with the coagulation system. And the faster and more aggressively these problems are treated, the better the patient does. So much so that in state of the art facilities, the policy is that in the shocked trauma patient, the FLUID OF CHOICE for restoring volume is . . . you guessed it . . . plasma.

Enough background. Lets look at what the Holmatro team no doubt did, and how they kept Hinch alive long enough for the surgeons to save him.

There is no doubt that at the scene they were confronted with exsanguinating hemorrhage. Their first priority then was to get James out of the car, and to stop the bleeding, even temporarily. If the site of the bleeding was far enough down the thigh to allow use of a tourniquet, they certainly applied one, high and tight. If it was higher, precluding use of a tourniquet, they used modern wound dressings that contain substances that induce a powerful local formation of blood clots (called “hemostatic dressings”). In fact, they likely used both.

(This is another reversal in “standard” practice. It is still taught that tourniquets are last resort items. In fact, with exsanguinating extremity bleeding, they are the FIRST resort. Terry understood this intuitively with Alex in Germany, but it has not -yet – become the new normal. Once again, thanks to the military trauma docs for this.)

The Holmatro guys no doubt put in a few fat IV lines, but only infused enough fluid to keep Hinch (barely) alive, for fear of creating the situation I referred to above. They also probably gave him any of the O neg (universal donor) blood available from the infield med center. In addition, they certainly administered tranexamic acid, an old drug that “boosts” the coagluation system and has been shown to dramatically reduce mortality from hemorrhagic shock.

Then then prioritised evacuating Hinch to the hospital, and, crucially, made sure that there was an operating room ready for him, and that the necessary blood products were prepared. Once admitted, once the surgeons got control of the bleeding, the anesthesiologists began to transfuse. Not just red blood cells, but also massive amounts of plasma and platelets too. In fact, the ratio was probably pretty close to 1:1:1.

Make no mistake about it – only the knowledge, skill and teamwork of the Holmatro team at the scene made it possible for Hinch to get evacuated alive. They deserve massive credit for this. I sure take my hat off to them.

Now for the surprise.

American racing is organised more along the lines of just a few teams, who travel with their respective championships and thereby gain tremendous experience working with each other, training with each other, and staying current with best practice guidelines.

In F1, for a number of reasons, each circuit fields what should be an autonomous team. The FIA Medical Delegate and Medical Rescue Coordinator are only there, nominally, to provide liaison, coordination, and to confirm that regs are followed.

Long story short? Of the 20 races of the season, at best five to seven of these “autonomous” teams would be capable of saving James, had that accident happened at an F1 event. These are the teams that are mature, stable, experienced, and well led. And it’s not always the ones you’d think of that are up to the task.

There are a number of reasons for this, not least of which are high turnover in teams, lack of training, and lack of team member participation in prehospital trauma care in the “real world”. This is not new. When I was involved in F1 I continually trumpeted this fact to the hierarchy. Given that a permanent FIA team attending all races is just not realistic, I constantly pushed for more intensive simulation based training. The hierarchy found it politically inexpedient to deal harshly with the local Chief Medical Officers whose lack of leadership contributed to this. Remember, it’s the national federations who go on to vote for the FIA president.

Don’t get me wrong – the Medical Rescue Coordinator is present at every race, and is a massively experienced trauma doctor, fully equipped both in terms of knowledge, skills, equipment and leadership. And even at the majority of circuits where the local team would not be able to handle an accident as dramatic as James’, he has at his disposal sufficient “manual labor” to get the job done. That said, one must not labor under any illusions. If we imagine the same accident at every race of the season, the outcome will vary, sometimes dramatically, depending on where we are.

While the solutions to this are not simple (or cheap, no doubt), they do exist. All that’s necessary is the will and leadership to get the job done, and to improve the standards everywhere. And of course, the “knock-on” effects of such a commitment, both in terms of “lower” series as well as in trauma care in general, can’t be ignored.

Thanks for your patience.

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