After I wrote a recent article on the benefits of the face flick for assessing level of consciousness, I received a string of questions and commentary on the effectiveness of another, more well known assessment for unconsiousness – the hand drop test.
The hand drop test is considerably more well known than its cousin the face flick and it remains a fairly reliable, though somewhat controversial test.
There’s a reason why the hand drop test is so well known. It tends to work. It’s a clever and reliable way to force a patient to make a decision and reveal their true mental status.
When done properly it’s harmless and does not require forcing pain or noxious stimuli on the patient. It also has the advantage of being appropriate to perform in front of family and loved ones. Unlike the face flick which is a bit to obnoxious for public consumption, the hand drop can be performed anywhere and looks like a fairly standard neurological test. If you don’t have this one in your tool box yet, it’s time to add it. If you do know it, let’s review it. There are some subtle elements to doing the hand drop test accurately and safely.
What we’re going to do with the hand drop test is test the patients muscle tone and cognitive ablitity with one move. Without warning, we gently pick up the patients hand and hold it above their face. Without delay, we drop it. If the patient were truely unconsious, the hand would fall and strike them in the face. Most likely on the mouth or chin. We’re not going to let that happen, but the patient doesn’t know that.
You see, the instant that we drop the hand, the patient has a decision to make. Patients don’t know what their hands are supposed to do when dropped over their face and the idea of striking themselves is instantly unappealing. But what to do instead? The resulting dilemma is both revealing and, often, hilarious. The amusing nature of watching a conscious patient decide what to do with their falling hand is certainly part of the popularity of this exam.
Now for a few of the finer points of technique.
One mistake that can lead to inaccurate results is allowing the patient’s hand to hover too long over the face before dropping it. Remember that the success of the test is dependant on the patient not having time to decide what to do with the hand. If you allow them to ponder what should happen to their hand before you drop it, you’re going to get inaccurate results. Don’t lift the hand until you’re ready to drop it.
The next error is not protecting the patient face. The hand drop test is indeed a test. If you’re already certain that the patient is conscious then there’s no need to do this. If you’re uncertain, then you should be protecting their face. As you lift the patients hand with one hand, place your other hand just above their face to protect it. It’s embarrassing to bring a patient in with a fat lip or a swollen nose and have to report that you did it playing “stop hitting yourself” with the unconscious patient.
It’s also a good idea to protect the patients elbow as well. Get ready to grab their arm because it should fall flaccid at their side if they are unconscious. Make sure the elbow isn’t on a collision course with something like a pram railing.
I find the hand drop remarkably reliable on all but the quickest thinkers. Conscious patients who pass the hand drop test tend to be folks who’ve played the game before and know that it might be coming. Some folks just become darn good at feigning unconsciousness. It’s a sad but true fact of emergency care.
And while this last part should go without saying, I’m going to put it in here anyway. No test is completely accurate regarding level of consciousness. People presenting with altered mental states and verbal unresponsiveness need to be treated as unconscious regardless of our suspicions based on tests such as these.
If you develop the habit of blowing off your patients because they fail tests like the hand drop and the face flick, you’re bound to get caught with your proverbial clinical pants down sooner or later. A bad day indeed.
What other tests do you find useful in determining level of responsiveness?