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Can a New “Sniff Test” Help Unresponsive Brain Injury Victims?

Severe injuries require emergency medical attention. When called upon to address these injuries, doctors must act quickly to diagnose and treat them as effectively as possible; many times in an effort to save the victim’s life. Brain injuries are a type of injury that can leave victims unresponsive, making the job of medical personnel extremely challenging when it comes to gathering the necessary information to make a proper diagnosis and deliver treatment.

Many times, with a traumatic brain injury, it is difficult to tell the actual state of the victim and whether he or she is likely to recover consciousness or remain in an unconscious state. Chattanooga and other Tennessee residents may be surprised to know that the diagnostic error rate in these situations is about 40%.

What is the “sniff test,” and is it accurate?

Traumatic brain injury researchers, after many years of study and testing, have recently developed a new test that can improve the chances of performing a fast and accurate diagnosis of individuals with brain trauma. This test does not involve the application of some new state-of-the-art technology, but on a simple test of the senses. It is referred to as “the sniff test” and the results, published in April in Nature, highlight the importance of olfaction (smell) in brain function.

The sniff test involves placing small quantities of strongly-scented products such as bath shampoo or smelly fish under the nose of an unresponsive patient. This is done while a special tube placed in the patient’s nose measures the response of the brain based on how the patient’s breathing responds to the odor.

A brain injury patient’s consciousness can vary after sustaining a brain injury. For this reason, scientists performed the test several times on the same patients. From the patient’s response to the smell, the scientists determined whether a patient sensed the smell to any degree, whether the patient could distinguish if it was a pleasant or unpleasant odor, and whether the patient anticipated something appealing or unappealing based on the previous odor provided.

Researchers also employed standard behavioral tests to measure each patient’s consciousness after performing the sniff test. Every patient who “sniffed” eventually exhibited symptoms of consciousness. All of the patients who remained in an unconscious state and later determined to have unresponsive wakefulness syndrome never showed a sniff response. When patients did sniff, the test was shown to be 100% accurate – these patients did regain consciousness. However, the test was only 65% accurate when patients did not sniff, which means 35% recovered consciousness who had not responded to the stimuli with a sniff.

The speed with which a doctor can accurately determine the future response of brain injury victims in terms of whether they are likely to regain consciousness or not can help significantly in knowing how to provide proper treatment. This test represents a potentially significant breakthrough in making this determination, particularly when every second counts for these victims in the aftermath of a traumatic brain injury.

The potential to save the lives of TBI and head injury victims

In the immediate aftermath of a brain injury, the sniff test could prove most beneficial, according to Joseph Giacino of Harbor Medical School and Spaulding Rehabilitation Hospital. Some families and physicians are compelled to withdraw life support when they receive the results of brain imaging that indicates little to no possibility of the victim recovering consciousness. This happens despite the fact that approximately 20% of patients recover some ability to function independently within five years. The results provided by the sniff test could prevent future premature determinations to withdraw a patient’s life support.

The sniff test adds to the diagnostic toolbox already present with standardized behavioral assessments and neuroimaging testing. These three tests combined provide medical professionals with the opportunity to reduce the high misdiagnosis rate involving traumatic brain injuries that leave individuals unconscious.

Whether traumatic brain injury occurs because of a car accident, truck accident or other devastating event, victims and their families can endure many years of suffering and struggle as a result. Even if the victim regains consciousness, he or she may have lost the ability to work and have to endure a long road of rehabilitation that is accompanied by pain and difficulty. If the accident that led to the brain injury was the fault of another party, the victim has a right to pursue compensation to offset his or her losses.

If you have sustained a traumatic brain injury because of someone else’s negligence, our experienced Chattanooga brain injury attorneys at Wagner Workers Compensation & Personal Injury Lawyers are here to fight for you. We can thoroughly investigate your case, determine the responsible party or parties, and pursue the compensation you deserve, either through a negotiated settlement or a significant jury award. To set up a free consultation about your case, call our law office today at 423.756.7923 or complete our contact form. We serve clients in and around Chattanooga and Cleveland, TN, and throughout North Georgia.