Eight months ago I blogged about inline stabilization vs inline traction of the cervical spine. Click here to read the post. A reader recently asked what the optimal method for inline stabilization is.
We’ve been pondering this question for nearly 30 years. In 1983, trauma surgeons at UCLA looked at a number of devices available at that time and tested them on normal volunteers. They measured neck motion to see which was “best."
Here’s what they found:
- Soft collar – In general, this decreased rotation by 8 degrees but insignificantly protected against flexion and extension. Basically, this keeps your neck warm and little else.
- Hard collars – A variety of collars available in that era were tested. They all allowed about 8% flexion, 18% lateral movement, and 2% rotation. The Philadelphia collar allowed the least extension.
- Sandbags and tape – Surprisingly, this was the best. It allowed no flexion and only a few percent movement in any other direction.
The Mayo clinic compared four specific hard collars in 2007 (Miami J, Miami J with Occian back, Aspen, Philadelphia). They found that the Miami J and Philadelphia collars reduced neck movement the best. The Miami J with or without the Occian back provided the best relief from pressure. The Aspen allowed more movement in all axes.
And finally, the halo vest is the gold standard. These tend to be used rarely and in very special circumstances.
- For EMS: Rigid collar per your protocol is the standard. In a pinch you can use good old tape and sandbags with excellent results.
- For physicians: The Miami J provides the most limitation of movement. If the collar will be needed for more than a short time, consider the well-padded Occian back Miami J (see below).
- Efficacy of cervical spine immobilization methods. J Trauma 23(6):461-465, 1983.
- Range-of-motion restriction and craniofacial tissue-interface pressure from four cervical collars. J Trauma 63(5):1120, 1126, 2007.
EMS in the field and physicians in the ED are faced with rapidly assigning some degree of stability to the patients they treat. What exactly are the shades of stability, and what considerations are there for each degree?
In my mind, there are three levels of “stability”:
- Unstable – this one is easy to figure out. The patient has obvious physiologic compromise, which may be objective (low blood pressure, low GCS or poor neuro exam, etc) or subjective (just plain looks bad).
EMS: These patients need transport to an appropriate level trauma center (I or II) immediately. If they need airway control or IV access that can’t be obtained in the field, stop at the nearest Level III or IV for assist, then continue on your way FAST.
ED: These patient must be a trauma activation. If not activated as your top-tier trauma, activate or upgrade now! These patients must be seen by a trauma surgeon immediately, and can only go to the OR. No diagnostics outside the resuscitation room are allowed unless they can be converted into one of the two stability levels below.
- Stable – this one is usually easy to figure out, too. These patients look good, have good vitals, and a low to moderate energy mechanism for their trauma. Look out for those few patients that may be hiding something like moderate bleeding into some body cavity.
EMS: Follow your usual transport protocols to select the closest, appropriate hospital.
ED: Follow your standard protocols for trauma activation if needed. Transport for standard imaging is fine.
- Metastable – this is a term I invented. It describes patients who have evidence of ongoing volume loss that can be controlled with infusion of crystalloid and/or blood products. It is possible to maintain a certainly level of stability using higher than normal volume infusions. This allows physicians to consider diagnostics or interventions outside of an OR.
EMS: Ensure adequate IV access and give fluids and/or blood per your local protocols. Transport to a Level I or II trauma center as quickly as possible.
ED: Activate or upgrade to your highest level of trauma activation. The trauma surgeon needs to be present to help direct diagnostics or interventions. These patients may go to CT, IR or other appropriate areas with nurse and physician accompaniment to diagnose and possibly treat bleeding. If the patient changes to unstable at any point, they must immediately be taken to the OR.
I am interested in other opinions on this as well. Please post your comments!
The Centers for Disease Control and Prevention (CDC) published a set of Guidelines for Field Triage two years ago. Click here to download them. They list 4 tiers of activation criteria to help prehospital providers triage patients appropriately to trauma centers.
Tier 1, which are physiologic criteria, and Tier 2 (anatomic criteria) are very accurate in predicting injury serious enough to require trauma team activation. Tier 3 contains mechanism criteria, and many centers who use these verbatim in their activation criteria end up with a fair amount of overtriage. Some centers even see a significant number of patients who meet Tier 3 criteria go home from the ED!
The Yale department of Emergency Medicine looked at intrusion into vehicle criteria (more than 12" near an occupant, more than 18" anywhere on the vehicle) to see if they are a valid predictor for admission or trauma center transport. It was a retrospective review of EMS transports to the Yale ED or to one satellite site.
Unfortunately, the number of vehicles that met intrusion criteria (48) was small compared to the number without significant intrusion (560). This makes the data a little less convincing than it may have been. The likelihood that intrusion would require trauma center admission (Positive Predictive Value) was only 26%. The likelihood that trauma center resources would be utilized (for issues like death, ICU stay, operation, spinal injury or intracranial hemorrhage) was only 13%. The authors recommend that the CDC guidelines be tweaked based on this data.
Bottom line: I think the numbers are far too small to convince the CDC to change their guidelines. But I would urge each trauma center that uses the intrusion criteria for activation to carefully study how many of those patients have minor injuries or go home from the emergency department. They may find that they can rely on other more accurate criteria and decrease their overtriage rate at the same time.
Reference: Motor vehicle intrusion alone does not predict trauma center admission or use of trauma center resources. Prehospital Emerg Care 15:203-207, 2011.
Eight years ago, the National Association of Emergency Medical Services Physicians (NAEMSP) and the American College of Surgeons Committee on Trauma (ACS-COT) released guidelines regarding withholding or terminating resuscitation in traumatic cardiopulmonary arrest (TCPA). Survival rates were extremely low (<2%) and were thought to have poor outcomes. But validation of the guidelines has been challenging, and some even doubted that EMS personnel could accurately assess these patients in the field!!
Researchers at Mt. Sinai Hospital in Chicago performed a large retrospective study of all patients in TCPA brought to their hospital by the Chicago Fire Department over at 7.5 year period. These patients met exclusion criteria but had been resuscitated anyway. Their series was relatively large (294 patients), and looked not only at the ultimate outcome, but also at EMS performance and cost.
They found that field assessments by EMS were very accurate and consistent. Violation of the guidelines resulted in only 6 survivors, and they all were resuscitated to a neurologically devastated state (4 brain dead, 1 family withdrew support, 1 sent to TCU with long-term GCS 6). No loss of neurologically intact survivors would have occurred if the guidelines were followed. Finally, the cost of trying to resuscitate these patients was $385,000 per year.
Bottom line: EMS can and should apply the NAEMSP/ACS-COT criteria for traumatic cardiopulmonary arrest and withhold resuscitation for these patients. Tragically, it is an expensive waste of time to try to bring them back.
To review the NAEMSP guidelines, click here.
Reference: The consequences of violating current guidelines regarding resuscitation of patients in prehospital traumatic arrest. Presented at the 34th annual Residents Trauma Paper Competition at the 89th Annual Meeting of the ACS Committee on Trauma, March 10, 2011.
One of the critical maneuvers that EMS providers perform is establishing initial vascular access. This IV is important for administering medications and for initiating volume resuscitation in trauma patients. Prehospital Trauma Life Support guidelines state that every trauma patient should receive two large bore IV lines. But is this really necessary?
The upside of having two IVs in the field is that the EMS provider can give lots of volume. However, a growing body of literature tells us that pushing systolic blood pressure up to “normal” levels in people (or animals) with an uncontrolled source of bleeding can increase mortality and hasten coagulopathy.
The downside of placing two lines is that it is challenging in a moving rig, sterility is difficult to maintain, and the chance of a needlestick exposure is doubled. So is it worth it?
A group at UMDNJ New Brunswick did a retrospective review of 320 trauma patients they received over a one year period who had IV lines established in the field. They found that, as expected, patients with two IVs received more fluid (average 348ml) before arriving at the hospital. There was no increase in systolic blood pressure, but there was a significant increase in diastolic pressure with two lines. The reason for this odd finding is not clear. There was no difference in the ultimate ISS calculated, or in mortality or readmission.
Bottom line: This study is limited by its design. However, it implies that the second field IV is not very useful. The amount of extra fluid infused was relatively small, not nearly enough to trigger additional bleeding or coagulopathy. So if another IV does not deliver significant additional fluid and could be harmful even if it did, it’s probably not useful. Prehospital standards organizations should critically look at this old dogma to see if it should be modified.
- Study of placing a second intravenous line in trauma. Prehospital Emerg Care 15:208-213, 2011.