Eyelash Reflex

[fireflymedic]

A previous topic discussed the issue of a pseudoseizure patient that appeared to be unconscious, but really wasn't. I've in the past used the eyelash reflex (rubbing finger over eyelashes seeing if the flicker or they blink) to assist in determining consciousness (have also been told it's a pretty verifiable means of finding out whether they can protect their own airway or not ). Obviously there are exceptions to every rule - but how prevalent is this practice. And also - has anyone ever used corneal reflexes? Just curious.

[Brady]

We use the eyelash deal on people. We get alot of fakers from jail. People that think they can prolong the deportation process. Maybe next time just for fun explain to your partner you are going to check for an anal wink, maybe that will get your pt to come around...

[crotchitymedic1986]

You can also lift their arm up so that it is perpendicular to their body, over their head, and let it go. If they are awake, they will not let their arm hit themselves in the head or body, but will instead let it flop to the side, not hitting their body.

Whatever you do, dont be the type of medic who puts alcohol swabs in a syringe, and then squirts the alcohol up their nose. Many in our field do that, and it is inappropriate.

[fiznat]

Yeah I do the eyelash thing, and the "arm drop test." They aren't legitimate examination techniques as far as I know, but I've anicdotally found them to be fairly reliable indicators of who is unconscious and who is not. I've also seen providers try the "arm drop test" and have unconscious patients whack themselves right in the face haha, so be careful with that one...

[fireflymedic]

Crotchity - I do recall the discussion of the alcohol and no, I am not that type of medic, far from it. The reason I was curious of this was I had seen it mentioned within a text and wondered how widespread the use was. I have used it previously and yes I do find it to be somewhat reliable (however as I said there are exceptions to everything). As far as the arm drop, that is falling quite out of favor very quickly. Harm can be done, however with the eye lash test no harm is ever done to the patient which makes it superior in my book. I think the context of the question was missed.

[fiznat]

however with the eye lash test no harm is ever done to the patient

YOU COULD POKE HIS EYE OUT!!!!!!!1one

[croaker260]

A previous topic discussed the issue of a pseudoseizure patient that appeared to be unconscious, but really wasn't. I've in the past used the eyelash reflex (rubbing finger over eyelashes seeing if the flicker or they blink) to assist in determining consciousness (have also been told it's a pretty verifiable means of finding out whether they can protect their own airway or not ). Obviously there are exceptions to every rule - but how prevalent is this practice. And also - has anyone ever used corneal reflexes? Just curious.

From wiki:

The corneal reflex, also known as the blink reflex, is an involuntary blinking of the eyelids elicited by stimulation (such as touching or a foreign body) of the cornea, or bright light, though could result from any peripheral stimulus. Stimulation should elicit both a direct and consensual response (response of the opposite eye). The reflex consumes a rapid rate of 0.1 second. The evolutionary purpose of this reflex is to protect the eyes from foreign bodies and bright lights (the latter known as the optical reflex).[1] The blink reflex also occurs when sounds greater than 40-60 dB are made.[2]

The reflex is mediated by:

the nasociliary branch of the ophthalmic branch (V1) of the 5th cranial nerve (trigeminal nerve) sensing the stimulus on the cornea, lid, or conjunctiva. the 7th cranial nerve (facial nerve) initiating the motor response. possibly mediated by a medullary center.

Use of contact lenses may diminish or abolish this reflex.

The optical reflex, on the other hand, is slower and is mediated by the cortex (outer covering) of the occipital real lobe of the brain. The reflex is absent in infants under 9 months.

The examination of the corneal reflex is a part of some neurological exams, particularly when evaluating coma. Damage to the ophthalmic branch (V1) of the 5th cranial nerve results in absent corneal reflex when the affected eye is stimulated. Stimulation of one cornea normally has a consensual response, with both eyelids normally closing.

A brief online review of literature finds numerous discussions of this reflex in mammles dating back to the early 1900's, so it is fairly well documented. Its application to anesthesia is also well documented, but (to my understanding) been replaced by more reliable methods.

In my personal experiance the Blink reflex , when absent, is usually a fair (not great, but fair) and objective indicator of LOC. In absent, it is (IMHO) one of the more benign indicators of weather someone has lost their gag reflex. Far better than direct stimulation of the gag relefx via a tongue depressor wich I have seen done on several occasions. HOWEVER, the inverse is not true. When present, it does NOT indicate that the gar relfex is intact.

KEY POINT: And either way an intact gag relflex does not indicate a patent or protected airway.

Far better is whether a patient can swallow or cough on command.

[Richard B the EMT]

The "Hand Drop Over Face" technique I've heard of, not so the alcohol up the nose. Besides, as I'm BLS, per protocols, I don't have access to a syringe.

New York State DoH outlawed "Ammonia Inhalants", sometimes called "Snappers", over 30 years ago. Does anyone have them still included in local protocols? Please give the area/country, if you do, just for my own interest and curiosity.

[FL_Medic]

The following article explains this topic well. Better than I could.

Beyond the Basics: Interpreting Altered Mental Status Assessment Findings

EMS providers frequently encounter patients who are not alert and present with an altered mental status, meaning their level of brain function is in question. Various physical examination techniques are employed during the assessment to determine the level of cerebral function and integrity of the brainstem. It is important to understand the limitations of these techniques, as well as potential findings that may cause you to erroneously interpret, report and document the level of brain function. This information is often used to identify trends to determine if the patient's condition is deteriorating, remaining the same or improving.

ANATOMY OF A CONSCIOUS STATE

Two structures are responsible for a conscious state: the ascending reticular activating system (ARAS) and the cerebral hemispheres. The ascending reticular activating system is not truly a single tangible anatomic structure; however, it is a network of nerve cells and fibers that extend from the spinal cord through the lower brainstem and continue upward toward the mesencephalon and thalamus. The impulses are then distributed throughout the cerebral cortex. The ARAS continuously receives sensory input that allows the body to remain in a wake or sleep state, remain aware of surroundings and respond appropriately while awake. The ARAS has an effect on both the autonomic nervous and motor systems, which in turn control the body's cardiovascular, respiratory and motor response to external stimuli.

Consciousness requires the patient to have an intact ARAS and at least one cerebral hemisphere. If either the ARAS or both cerebral hemispheres are affected by a particular condition and not functioning properly, the patient will not remain in a wake or alert state. Head injuries, severe cerebral hypoxia or anoxia, central nervous system-depressant drugs and electrolyte disturbances are only a few of the possible factors that would disrupt the function of the ARAS or both cerebral hemispheres and render the patient unconscious.

Several assessment techniques may be used during the physical exam to determine the brain's ability to receive, transmit, interpret and respond appropriately to an external stimulus applied to the body. One of the most common techniques is a painful stimulus applied to a patient who is not alert or not responding to verbal stimuli. The patient's response assists the examiner in determining the extent or level at which the brain is able to function. Continuous reassessment provides valuable input when considering a differential diagnosis; making a decision on providing more advanced emergency medical care; and determining whether your treatment is improving the patient's condition, if the patient is remaining stable or if the condition is deteriorating.

AVPU

The mnemonic AVPU is universally used by EMS personnel at all levels to determine a patient's mental status. Historically, AVPU was used only to assess eye-opening to various stimuli; however, it has evolved to a more general interpretation of patient responses. A refers to alert. An alert patient opens his eyes spontaneously upon your arrival at his side. If the patient is alert, there is no reason to continue with the AVPU assessment. It would be prudent to determine if the patient was oriented to person, place and time.

If the patient does not have spontaneous eye-opening, V is the next step in the AVPU process, which is achieved by using a verbal stimulus in an attempt to get the patient to respond. Historically, the patient was asked specifically to "open your eyes" when applying the verbal stimulus. If eye-opening was attained, the patient was said to have responded to a verbal stimulus. Today, many emergency services providers ask the patient to "squeeze my fingers" or "wiggle your fingers" in place of the traditional eye-opening command. Again, if the patient responds to a verbal stimulus, there is no need to continue.

P refers to painful stimulus applied if the patient did not respond to a verbal stimulus. Originally, this test was used to determine if the patient opened his eyes when a painful stimulus was applied. When emergency medical services personnel utilize a painful stimulus, they are watching for any indication of a response, whether it is flexion, extension, withdrawal of an extremity or localization of the pain by attempting to remove it. As evidenced by the numeric rating on the Glasgow Coma Scale (GCS), a higher score is awarded for a more specific response. For example, if the patient wiggles his fingers upon command, he is awarded a 6the highest score possible. Five points are awarded if he localizes the pain; 4 points are given if he withdraws to a painful stimulus. A higher score on the GCS correlates with better brain function.

If there is no response to a painful stimulus, the patient is said to be unresponsive, which represents the U in AVPU. A patient who does not respond to noxious stimuli is considered comatose.

MISINTERPRETING NO RESPONSE TO A STERNAL RUB

Sternal rub is one of the primary methods used by EMS for applying a painful stimulus. This technique is performed by rubbing the knuckles of a closed fist firmly and vigorously on the patient's sternum. Because the stimulus is applied to the core of the body, it is referred to as a central painful stimulus. The intent is to determine the type of response to pain, which will provide an indication of the patient's level of brain function. As previously mentioned, a more specific response, such as reaching up and removing the knuckles from the chest, correlates with a higher level of brain function. If no response is elicited, the examiner would assume the brain function is extremely poor.

Anecdotal reports from neurology nurses and physicians have noted that it may take up to 30 seconds of sternal rub to get a response from the patient. Most emergency service personnel only apply hard knuckle pressure to the sternum for a few seconds. If no response is achieved in this brief period of time, brain function is thought to be poor and mental status is noted as being unresponsive. However, if the sternal rub was applied for 30 seconds, the patient may have actually responded. Thus, no response to a sternal rub that is applied for less than 30 seconds may provide an inaccurate finding in the mental status. Keep in mind that the sternal rub only needs to be applied until a response is elicited.

In the prehospital environment, it is not realistic or desirable to apply a sternal rub for 30 seconds during the initial assessment. On the scene of an emergency, the entire initial assessment should be performed in less than 60 seconds! Consider an alternative central painful stimulus technique like the trapezius pinch or supraorbital pressure to ensure a more accurate finding during the physical examination.

The trapezius pinch is applied by grasping approximately two inches of the trapezius muscle at the base of the neck between your thumb and index finger. Simultaneously twist and squeeze the muscle firmly and watch the patient's face for a grimace, eye-opening or some other response. Listen for a groan, moan or other incomprehensible sounds or comprehensible words. Watch the extremities for any movement that includes an attempt to remove the stimulus.

To apply supraorbital pressure, it is necessary to locate the bony ridge along the superior border of the orbit that contains the eyeball. Pain and severe discomfort are achieved by applying a straight upward pressure with the tip of the thumb to the midline of the supraorbital bony ridge. Be sure your thumb is on the bony ridge and no pressure is being applied to the eyeball, which can damage the globe or promote a vagal response. While pressure is being applied, watch the patient's face and extremities for a response, or listen for a comprehensible or incomprehensible response.

MISINTERPRETATION OF A PERIPHERAL RESPONSE TO PAINFUL STIMULUS

EMS personnel may elect to apply a painful stimulus to an extremity, which is referred to as a peripheral painful stimulus. The fingernail bed is compressed between the examiner's downward thumbnail pressure and the index finger, or the skin or web of soft tissue between the patient's thumb and index finger is pinched. The response to a painful stimulus applied to an extremity may also provide a finding that can be easily misinterpreted due to a spinal reflex arc.

If a painful stimulus is applied to the extremity and the patient does not respond, one would interpret this as an indication of poor cerebral function. However, if the patient withdrew his arm or leg when the painful stimulus was applied, it would be interpreted, reported and documented as withdrawal to pain. This may be an indication of a higher level of cerebral function and the patient would be awarded a 4 on the Glasgow Coma Scale for best motor response. If the patient responded, the examiner would assume the impulse traveled via an afferent (sensory) nerve fiber to the spinal cord, up a spinothalamic tract to the brain, where the pain impulse was interpreted and an appropriate response was sent down the spinal cord via a corticospinal tract and out to the muscle by an efferent (motor) fiber, causing the patient to withdraw from the pain. Thus, it is assumed from the withdrawal response to painful stimulus that the patient's brain received the impulse, interpreted it correctly and sent down an appropriate response.

The spinal cord has the ability to produce a reflex response when pain is applied to cutaneous sensory receptors in the extremities. When pain is applied to the extremity, the impulse travels via an afferent nerve fiber to the spinal cord, where it triggers a pool of interneurons. These neurons then return the impulse immediately via an efferent (motor) nerve fiber to flexor muscles in the extremity. The result is withdrawal of the extremity from the painful stimulus. This is often referred to as a spinal reflex arc. Interestingly, the reason for applying a painful stimulus to the extremity is to assess the integrity of brain function; however, in the case of a spinal flexor reflex response, the impulse creating withdrawal of the extremity never traveled to the brain. In this patient, the examiner misinterprets withdrawal of the extremity that was produced by the spinal flexor reflex as being a good sign of cerebral function when the brain never received or invoked the response.

If a spinal flexor reflex is triggered by applying pain to an extremity, the examiner would interpret, report and document the flexion of muscles as an appropriate withdrawal response to pain and award the patient a 4 on the GCS, even though the brain was not involved in the response. Thus, be careful in your interpretation of withdrawal when pain is applied to an extremity. This is contrary to misinterpretation of a lack of response to a briefly applied sternal rub.

BLINK TEST

Some patients encountered in the prehospital setting may fake an unresponsive state for a variety of reasons. Various techniques are used by the emergency personnel to distinguish between a patient faking a coma and one who is truly comatose. A common practice is to drop the patient's hand onto his face. If the hand slips to the side of the patient's face, it is commonly interpreted as a purposeful movement with the intent to not strike the patient directly in the face, which would indicate he is not truly comatose. A patient is thought to be comatose if the hand is dropped directly onto his face with no attempt by him to redirect it. Be cautious when interpreting this response, because there are patients who are intent on making the examiner believe they are unresponsive.

An examination that may be applied to a patient who appears to be unresponsive but is thought to be faking is the blink test. This is performed by snapping your fingers in front of the open eyelid or making a motion with your fingers as if you are going to poke the patient in the eye. If the patient blinks, you may interpret this as a sign that the patient is faking the unresponsive state. The patient who truly is unresponsive cannot see the snapped fingers or fingers coming in to poke his eye; however, he may blink his eyes when these techniques are performed due to a corneal reflex. When air passes over the cornea, the corneal reflex causes the eyelid to blink, even though the patient may not be able to respond to other stimuli. In the blink test, snapping the fingers or movement of the finger toward the eye may cause air to pass over the cornea, eliciting a blink. The examiner may misinterpret this blink as being an indication that the patient can see the fingers and is faking the coma.

PALMAR GRASP REFLEX

The palmar grasp is a primitive reflex that appears at birth and is present until the infant is 5 to 6 months of age. When the palm of the hand is stroked, the infant will close his fingers and grasp the object in his hand. When the back of the hand is stroked, the infant will open his fingers.

An adult patient who is not alert and is being assessed for responsiveness to verbal stimuli might be asked by the examiner to "squeeze my fingers" to determine if he is able to obey the command. If the patient squeezes or grasps the examiner's fingers, it would be interpreted as a finding that the patient is able to obey commandsa good indication of a higher level of cerebral function.

If an adult patient suffers an injury to the frontal lobe, the primitive palmar grasp reflex may become active once again. If the examiner happens to stroke the palm of the patient's hand as he is asking the patient to "squeeze my fingers," he may trigger the palmar grasp reflex, which might result in the patient unconsciously and lightly grasping the examiner's fingers. This finding would then be misinterpreted as an appropriate response to a verbal stimulus when the patient may truly be unresponsive.

It is important to understand the limitations of certain techniques used in determining the level of responsiveness. The assessment findings can be misinterpreted and provide an erroneous interpretation of brain function. This may impact the differential diagnosis and possibly the emergency care provided to the patient.

CEU Review Form Beyond the Basics: INTERPRETING Altered Mental Status ASSESSMENT Findings (PDF) Valid until October 6, 2008

Bibliography

alton AL, Limmer D, Mistovich JJ, Werman HA. Advanced Medical Life Support: A Practical Approach to Adult Medical Emergencies, 3rd edition. Upper Saddle River, NJ: Prentice Hall, 2007.

Guyton AC, Hall JE. Textbook of Medical Physiology, 10th edition. Philadelphia, PA: W.B. Saunders, 2001.

Marieb EN. Anatomy and Physiology, 2nd edition. San Francisco, CA: Pearson Education, 2005.

;Martini FH. Anatomy and Physiology. San Francisco, CA: Pearson Education, 2005.

Marx JA, Hockberger, RS, Walls RM. Rosen's Emergency Medicine: Concepts and Clinical Practice, 5th edition. St. Louis, MO: Mosby, Inc., 2002.

Joseph J. Mistovich, Med, NREMT-P, is a professor and chair of the Department of Health Professions at Youngstown (OH) State University.

William S. Krost, MBA, NREMT-P, is director of Emergency Services & Health System Access for Blanchard Valley Health System in Findlay, OH.

Daniel D. Limmer, AS, EMT-P, is a paramedic with Kennebunk Fire-Rescue in Kennebunk, ME.

[CBEMT]

I had never done it to that point, but the night the local fire department brought in a"faking" patient that had "failed" the arm-drop test, and said patient turned out to have a large subdural bleed, was the night I resolved to never even bother with it.