Cervical collar

• Topic: Cervical collar: what is, what is NOT; How could it be used to the best
• Too often the cervical collar is used incorrectly: it is often used as the only immobilization tool; Is often considered to be without side effects; Often they are not considered for what has been designed and what is the recommended use.

• Paolo Formentini RN: trainer, experienced nurse, has been working for 22 years as a pre-hospital Emergency Nurse and as a ER Nurse. Has a blog (amicidel118.org ) where he presents emergency / urgent articles and an FB page (https://www.facebook.com/AmiciDel118/) where he presents algorithms and action cards in emergencies. He has written and published the “Emergency Vademecum” (c) Quick Reference Manual for Pre-Emergency Emergency Operators and writing his second “semeiotic nursing text for ER Operators”
• Paolo Formentini, Nurse. ER Unit / pre hospital unit (118) Vignola Hospital – AUSL Modena; 28 G. degli Esposti St.; S. Cesario s.p. Modena, Italy. +39 340 8621926

Cervical collar

1. Formentini RN

First of all, what is a cervical collar?
A cervical collar is a medical device used to assist the POSITIONING of the cervical spine in relation to the head and the rest of the body.
And what IS a cervical collar NOT?

• It is NOT a device intended to “fix/immobilize” the head
• It is NOT a device able to permanently and safely stabilize the head
• It is NOT a device to be employed without the use of other complementary devices
• It is NOT a device that can be applied by a single person
• It is NOT lacking side effects
• It is NOT a device that can or should be used in EVERY case of trauma

Some of these statements may sound strange or difficult to accept; nonetheless, they are true, as a matter of fact. As for other subjects (e.g. oxygen therapy), case studies and medical literature arise new questions and propose new solutions, as well as new procedures facing issues previously considered solved.

Types of cervical collars

Cervical collars can be grouped according to different principles. They are commonly grouped according to their features, i.e. soft and rigid cervical collars; they also can be classified according to their mechanics, i.e. one-piece and two-piece cervical collars; collars can also be adjustable or one-size, pediatric or for adult patients.

The first thing to remark is the difference between pediatric and adult collars. In fact, the proportions between the occipital bone and the rest of the body (the two fundamental points where the device lays) are different in children and adult patients; also, the proportion between the whole head and the rest of the body reports different values for children and adults. As a general rule, it is necessary to choose the correct device for each patient, taking into consideration its specific size and features.

Each device comes with specific application instructions; as a consequence, in case of a two-piece collar the back part must be fixed first; for other types of collars the correct application procedure could be exactly the other way round.

One type of collar is not better than the others in an absolute way  (except for soft collars, beyond doubt useless in emergency situations). The most suitable collar must be chosen according to the specific needs of the situation, its comfort during transport, the ease of application for the medical staff and, of course, its cost. Let me remark again that a collar is a positioning device, and not an immobilization device: this is why its application must strictly be TEMPORARY.

How to apply the cervical collar

The application instructions and the prescriptions provided by the constructor must always be respected; the operational procedures change according to the chosen model, nonetheless there are some general rules that should always be followed.

1. Evaluate the scenario (safety)
2. Approach the patient, immobilize her or his head and explain what is going on
3. Evaluate the patient’s state of consciousness
4. Remove clothes, necklaces, ties, etc. from the neck
5. Evaluate (by watching and touching) the presence of head crushes, injuries, relevant morphological modifications in any segment of the head or the spinal chord; verify the presence of pain (spontaneous or inducted), verify the presence of bleeding or liquid spill (liquor) from ears and nose; verify the presence of Beattle’s sign; evaluate the dynamic of the event, check the patient’s trachea, airways and pupils; evaluate the global conditions of the patient’s neck, face and head.
6. Choose the correct collar (pediatric or adult); choose the correct size or adjust the collar’s size (if adjustable) according to the patient’s morphology

Now follow the collar’s specific instructions of application. After the application of the collar, proceed with the patient’s positioning on a spinal board/scoop stretcher/other device for transportation to the hospital.

Never alone – practical uselessness

The cervical collar is a device that, if chosen, must never be applied by a single person. Indeed, if we choose to apply the collar, it is because we have considered the dynamic of the event, the patient’s fragility and the energy involved and we have estimated them as severe or high. These conditions imply caution during the patient’s immobilization. If the scenario suggests the application of the cervical collar, then we should ensure the best linearity between the cervical tract and the rest of the spine. The only way to ensure this and prevent ourselves and the patient from any damage, is to apply the collar with the help of at least another person: one person should be involved in the immobilization of the head, the other in the application of the device.

Consequences

As already mentioned, if we choose to apply the cervical collar it means that we have considered a number of factors that make the collar necessary for that specific situation. IF we choose to apply the collar, THEN the patient needs to be stabilized and transported in the safest way possible. IF we have applied a positioning device, THEN we need to make sure that the correct position will be maintained afterwards, in order to avoid traumas and secondary effects due to transportation. Devices assuring immobilization during transportation are: spinal board with straps and head-blocker; semi-rigid vacuum mattress; scoop stretcher provided with straps and head-blocker homologated for transport. The application of the collar IMPOSES the application of one of these other devices.

Why the cervical collar should not be used in EVERY situation

The cervical collar should be used in every case of suspected severe trauma; nonetheless, we must be aware of the possible counter-indications related to its use.

Scientific literature reports cases of increased intracranial pressure, reduced blood flow, ab ingestis, hyperextension of cervical spine due to incorrect application, discomfort and intolerance towards the device.

Side effects and counter-indications of the cervical collar

Some studies report, among others, the following side effects:

Increased agitation state, increased intracranial pressure due to neck compression (especially in case of spinal injuries), obstruction of the airways and obstructed view of the neck, increased ab ingestis risk.

When should the cervical collar be used? SUGGESTIONS

The cervical collar is indicated in every suspected case of spinal axis injuries, especially those involving the cervical tract (vertebrae C1-C7). The clinical cases and the dynamics that may occur are multiple, for example:

• Hyperextension of the head – dynamic with excessive forward movement of the head or neck
• Hyperflexion – dynamic with excessive backward movement of the head or neck
• Compression – dynamic with stress on the vertical axis of the head
• Excessive back/neck/head rotation
• Excessive lateral stress
• Strain – excessive pulling of the spine and of the neck’s nervous cords

In addition to this, we should consider dynamics where a load of energy is released on a single point and the energy released is superior to the physiological resistance of the tract c1-c7 (direct trauma on the tract c1-c7);

In any case, the TEMPORARY use of the cervical collar is recommended during every phase of transportation from the place of the trauma to the stretcher.

Another situation deserving particular attention is the case of a patient with reduced resistance in the tract c1-c7, as for example in patients suffering from a pathology of the bone tissue.  This is why, while evaluating a situation, I always prefer to consider the RATIO BETWEEN ENERGY/ MECHANISM/PHYSIOLOGICAL RESISTANCE, rather then the mechanism itself or the energy as factors isolated from the context: it is clear that the consequences of a light trauma on a patient with reduced defenses (for example elderly) compared to the consequences on a young and healthy person will be much different.

According to what mentioned above, I would like to suggest a table taking into account the ratio between “force”, “dynamic” and “resistance” to better evaluate the single situations.  Notice the stress given to the parameter “resistance”: while keeping a directly proportional ratio with the other parameters, its scoring system is based on a wider numerical scale in the evaluation phase.  I would suggest to add 2 extra points if there exist the possibility of alcohol or drugs consumption  (analgesia risk). Please, notice that the table I am suggesting must be accurately validated on the field.

In this PROPOSAL I have considered the risk of cervical injury as: LOW for scores 3 and 4; MODERATE for scores 5,6,7; HIGH for scores > 8.

As a consequence, the use of cervical collar could be AVOIDED in the first case, UNCERTAIN in the second case, CERTAIN in the third case.

Reading key for the table “use of cervical collar”

– force involved: presumed energy involved in the trauma; low energy: e.g accident car VS car with speed lower/equal to 30 km/hour; falling from standing upright or from heights inferior to 1 meter; medium force: falling from heights comprised between 1 and 3 meters, car accident with speed comprised between 30 and 50 km/hour; high force: falling from heights superior to 3 meters, car accidents with speed superior to 50 km/hour; dynamic: seriousness of the dynamic of the trauma; non dangerous dynamic: falling from standing upright with energy stressing an extended area of the body and not just a specific part of the body; medium risk dynamic: jumping from the vehicle falling within one meter from the vehicle itself, two or more fractures in the same bone segment; falling with energy stressing a single part of the body (for example falling with an impact on a step edge), accident car VS car with speed comprised between 30 and 50 km/hour without safety belts or with airbag only; high risk dynamic: jumping out of the vehicle more than one meter far from the vehicle itself, seriously injured/dead person inside the vehicle itself, car overturning in the middle of the street

– physiological resistance: HIGH: patient >6 <50 years old; absence of osteopathy-related pathology; MEDIUM: patient >50 <70 years old, presence of light osteopathy-related pathology, absence of vertebral collapse and serious osteopathy-related pathology; LOW: age >70 years old, presence of osteopathy-related pathology.

Alternative solutions

There are no alternative solutions to the use of cervical collar, apart from manual immobilization.

In the field of medical solutions, many models of cervical collar have been proposed along the time. None of them, nonetheless, is able to completely immobilize the head in relation to the rest of the body. The latest models can guarantee a higher level of immobilization (both in lateral and frontal direction) but they are more complicated to manage and to apply and furthermore they limit the sight of land marks and of the patient’s anatomy more than other models. If the application of the cervical collar is not feasible, the possibility of manually immobilizing the patient and fixing her or him on a spinal board with pillows and straps is always a good solution.

Conclusions

In case of patients with reduced physiological defenses and low resistance (for example elderly or patients with a pathology), or in case of serious dynamics and high force involved, the use of cervical collar is recommended even in absence of morphological modifications and/or spine pain, because, notably, some studies have reported that even in presence of a spinal fracture sometimes patients don’t perceive pain during palpation (27% of cases).

The use of the cervical collar alone to stabilize the cervical tract of the column is useless. Studies and meta analysis suggest that the cervical collar is not necessary; it could be used only from the collecting point until the final stabilization on a spinal board with straps and head-blockers.

If we choose to use the cervical collar IT IS NECESSARY AND REASONABLE TO USE ALSO ANOTHER IMMOBILIZATION DEVICE during transportation.

It might be useful to reconsider the operative and application procedures of the immobilization devices, taking into consideration also their side effects.

P.Formentini RN

Essential bibliography

Why EMS Should Limit the Use of Rigid Cervical Collars http://www.jems.com/articles/print/volume-40/issue-2/patient-care/why-ems-should-limit-use-rigid-cervical.html

ILCOR: spinal motion restrictrion posted following ilcor meeting task force discussion on 4 february, 2015

http://news.doccheck.com/it/blog/post/1432-uso-del-collare-cervicale-nei-traumi-nuovi-dubbi-sulluso-del-collare-cervicale-nei-traumi-lo-studio-norvegese/

Sundstrøm T, Asbjørnsen H, Habiba S, Sunde GA, Wester K. Prehospital use of cervical collars in trauma patients: a critical review. J Neurotrauma. 2014 Mar 15;31(6):531-40. doi: 10.1089/neu.2013.3094

Kim EG1, Brown KM, Leonard JC, Jaffe DM, Olsen CS, Kuppermann N; C-Spine Study Group of the Pediatric Emergency Care Applied Research Network (PECARN).Variability of prehospital spinal immobilization in children at risk for cervical spine injury.

http://www.ncbi.nlm.nih.gov/pubmed/23528499

disclaimer

THIS ARTICLE IS NOT INTENDED TO SUBSTITUTE THE CONSULTATION OF SPECIALIZED DOCTORS AND MEDICAL STAFF; ITS ONLY AIM IS TO INFORM A VAST AUDIENCE AND REACH SPECIALIZED STAFF WITH SUGGESTIONS OF USE OF THE AFOREMENTIONED DEVICE. ALWAYS CONSULT A DOCTOR, AN ANESTHETIST, OR A HEALTH-CARE ASSISTANT FOR THE NECESSARY RECOMMENDATIONS.