I’ve just spent two days here looking at the phenomenon of “delayed diagnosis” or missed injury. I believe that there are only two fundamental reason why this occurs:
- Insufficient diagnostic technique – A good physical exam and/or specific diagnostic techniques were not performed. Or rarely, the injury cannot be readily detected by existing techniques and technology. The former is usually the real problem, and may be an issue with either the physical exam completeness and/or technique, or judgment used to obtain the appropriate diagnostic test. Example 1: a penetrating injury to the back is missed because the patient is not logrolled to examine this area. Example 2: a spine fracture is missed in an elderly patient with a fall from standing because the back pain found on physical exam is evaluated only with conventional imaging of the spine, not CT.
- Failure to recognize the injury – The injury was actually identified on a test, but was not appreciated by the clinician. Example 1: the radiologist may not have appreciated and reported out a subtle anomaly in the cervical spine imaging. Example 2: you fail to check you patient’s lab tests and miss a sudden spike in serum amylase or lipase the day after your patient was kicked in the epigastrium by a horse.
So what can you do to avoid this potential problem? Here are some tips:
- Admit that it can really happen to you. If the missed injury rate at your center is off the low end of the bell curve (< 5%) then you are either really good or really blind. You’d better take a close look at your performance improvement process, because you may be fooling yourself.
- Adopt a firm definition of “delayed diagnosis.” Basically, you need a time frame after which a new diagnosis is considered “delayed.” It should be a reasonable time interval after the patient has left the ED. If it’s too short an interval (e.g. once they leave the ED), your number will be unnecessarily high. If it’s too long (days and days later), then significant morbidity may occur that you don’t account for. Most centers have adopted 24, 36, or 48 hours after patient arrival.
- Implement a tertiary survey process. This is a complete physical re-examination followed by a review of all diagnostic studies (lab and radiology) that have been performed. This exam needs to be dated and timed to ensure that it is performed within the time frame noted above. If a new finding is discovered on the tertiary survey, it is not considered a delayed diagnosis. If found after the survey (or after the pre-determined time interval), it is and must be entered into your performance improvement process.
- Be paranoid. I hate the phrase, “maintain a high index of suspicion” because it’s meaningless. It’s like those stupid “start seeing motorcycles” bumper stickers. You can’t see what you can’t see. But you can be suspicious all the time, constantly looking for the inevitable clinical surprises of trauma care.
Delayed diagnoses / missed injuries are with us to stay. The typical trauma activation is a fast-paced process, with lots of things going on at once. Trauma professionals are very good about doing a thorough exam and selecting pertinent diagnostic tests to seek out the obvious and not so obvious injuries.
But we will always miss a few. The incidence varies from 1% to about 40%, depending on who your read. Most of the time, they are subtle and have little clinical impact. But some are not so subtle, and some of the rare ones can be life-threatening.
The trauma tertiary survey has been around for at least 30 years, and is executed a little differently everywhere you go. But the concept is the same. Do another exam and check all the diagnostic tests after 24 to 48 hours to make sure you are not missing the obvious.
Does it actually work? There have been a few studies over the years that have tried to find the answer. A paper was published that used meta-analysis to figure this out. The authors defined two types of missed injury:
- Type I – an injury that was missed during the initial evaluation but was detected by the tertiary survey.
- Type II – an injury missed by both the initial exam and the tertiary survey
Here are the factoids:
- Only 10 observational studies were identified, and only 3 were suitable for meta-analysis
- The average Type I missed injury rate was 4.3%. The number tended to be lower in large studies and higher in small studies.
- Only 1 study looked at the Type II missed injury rate – 1.5%
- Three studies looked at the change in missed injury rates before and after implementation of a tertiary survey process. Type I increased from 3% to 7%, and Type II decreased from 2.4% to 1.5%, both highly significant.
- 10% to 30% of missed injuries were significant enough to require operative management
Bottom line: In the complex dance of a trauma activation, injuries will be missed. The good news is that the tertiary survey does work at picking up many, but not all, of the “occult” injuries. And with proper attention to your patient, nearly all will be found by the time of discharge. Develop your process, adopt a form, and crush missed injuries!
Reference: The effect of tertiary surveys on missed injuries in trauma: a systematic review. Scand J Trauma Resusc Emerg Med 20:77, 2012.
Major trauma victims are evaluated by a team to rapidly identify life and limb threatening injuries. This is accomplished during the primary and secondary surveys done in the ED. The ATLS course states that it is more important for the team to identify that the patient has a problem (e.g. significant abdominal pain) than the exact diagnosis (spleen laceration). However, once the patient is ready for admission to the trauma center, it is desirable to know all the diagnoses.
This is harder than it sounds. Physical examination tends to direct diagnostic testing, and some patients may not be feeling pain, or be awake enough to complain of it. Injuries that are painful enough may distract the patient’s attention away from other significant injuries. Overall, somewhere between 7-13% of patients have injuries that are missed during the initial evaluation.
A well-designed tertiary survey helps identify these occult injuries before they are truly “missed.” This survey consists of a structured and comprehensive re-examination that takes place within 48-72 hours, and includes a review of every diagnostic study performed. Ideally, it should be carried out by two people: one familiar with the patient, and the other not. It is desirable that the examiners have some experience with trauma (sorry, medical students).
The patients at highest risk for a missed injury are those with severe injuries (ISS>15) and/or impaired mental status (GCS<15). These patients are more likely to be unable to participate in their exam, so a few injuries may still go undetected despite a good exam.
I recommend that any patient who triggers a trauma team activation should receive a tertiary survey. Those who have an ISS>15 should also undergo the survey. Good documentation is essential, so an easy to use form should be used. Click here to get a copy of our original paper form. We have changed over to an electronic record, and have created a dot phrase template, which you can download here.
Tomorrow: Does the tertiary survey actually work?
Many trauma patients require implantable hardware for treatment of their orthopedic injuries. One of the concerns they frequently raise is whether this will cause a problem at TSA airport screening checkpoints (Transportation Safety Administration).
The answer is probably “yes.” About half of implants will trigger the metal detectors, and these days that usually means a pat down search. And letters from the doctor don’t help. It turns out that overall, 38% are detected when the scanner is set to low sensitivity and 52% at high sensitivity.
Here is a more detailed breakdown:
- Lower extremity hardware is detected 10 times more often than upper extremity or spine implants
- 90% of total knee and total hip replacements are detected
- Upper extremity implants such as shoulder, wrist and radial head replacements are rarely detected
- Plates, screws, IM nails, and wires usually escape detection
- Cobalt-chromium and titanium implants trigger alarms more often than stainless steel
If your patient knows that their implant triggers the detectors, they have two options: request a patdown search, or volunteer to go through the full body millimeter wave scanner. This device looks at everything from the skin outwards, and will not “see” the implant and is probably the preferred choice. If they choose to go through the metal detector and trigger it, they are required to have a patdown. Choosing to go through the body scanner after setting off the detector is no longer an allowed option.
Reference: Detection of orthopaedic implants in vivo by enhanced-sensitivity, walk-through metal detectors. J Bone Joint Surg Am. 2007 Apr;89(4):742-6.
And now, the last one in the series (for now).
You’ve just received a young male who had been stabbed under his right arm in your emergency department. He’s awake, talking, and very friendly. He met your trauma activation criteria, so you are cruising through the full evaluation. Lines in, blood drawn, clothes off. He wonders aloud if all this is really necessary.
Then, on FAST exam, you see it. A pericardial stripe that looks like a mix of liquid and clotted blood. Your colleague steps in and verifies the exam. But vital signs are normal, the patient is fine.
What next? CT of the chest to further define this? A formal echo to confirm? Your surgeon says no, we’re going to the OR, now! Reluctantly, you package the patient and send him on his way. In the OR, the anesthesiologist takes his time, putting in an arterial line, asking the patient unrelated questions. A thoracotomy? Really? The patient remains awake and alert through all of this.
So here’s the fourth law:
Even awake, alert, and stable patients die. And it hurts that much more when they do.
Bottom line: You know the diagnosis in this case. And you know what needs to be done. But the awake and alert patient fools us. Fakes us out. Somehow, we equate the ability to talk intelligently with being fine. But evil things can be going on inside that don’t rear their ugly head until it’s too late. Don’t get suckered! Believe your exam, not what the patient thinks they are telling you.
Other Laws of Trauma: