Editor’s note: This is part two of a series on basic assessments from EMS World. Read part one of the series on pedal pulse here.

Some of us have a hard time with basic assessments because they are either not practiced enough or are difficult to master.

As EMTs and paramedics, we work in a fast-paced industry that is perpetually moving forward with research and new practices. Because we constantly encounter new information and methods, it’s more important than ever to remember the basics.

This miniseries is designed to help strengthen and refresh your basic assessment skills.

Assessing a Patient’s Glasgow Coma Scale (GCS)

As one of our most critical assessments, performing this well can be the difference between staying on the ball or playing catch up on a call.

The central nervous system is responsible for every autonomic and somatic function in the body and is composed of the brain and the spinal cord. When its function is interrupted by outside factors, EMS providers can expect a varying degree of complications from the patient.

Although prehospital assessments are limited, they remain vital in determining which prehospital interventions might be required. While the brain is responsible for consciousness, decision making, hormones, speech, and behavior (and more), the spinal cord is responsible for relaying and receiving all innervations and instructions from the brain and the periphery.

GCS Interpretation

The most valuable assessment tool for determining a patient’s level of awareness is the Glasgow Coma Scale. This universal tool is used by clinicians as a powerful determiner of a patient’s mentation status.

The scale encompasses three categories representing motor response, verbal response, and eye opening. With a range from none to normal, this scale helps medical professionals make important clinical decisions for their patient.

When an EMT or paramedic first makes patient contact, they should be able to assess a patient’s GCS score without even placing hands on the patient. With the ‘look test,’ we are generally able to assess whether a patient appears critical or not.

This test starts when you first walk onto the scene and approach the patient. Most paramedics will introduce themselves or offer a greeting, which, in turn, can be used as an assessment tool, as it is solicits a response from the patient. All these factors contribute to an overall Glasgow Coma score.

Factors That Affect a Patient’s GCS

The following dynamics are indicators for a GCS interpretation. The lower a patient’s Glasgow Coma score, the more dynamic and unstable the patient is likely to be and become.

Head Injuries

Any trauma that results in a head injury such as a motor vehicle collision, blunt or penetrating trauma, or a fall from height indicates the need for a thorough assessment of a patient’s level of awareness (LOA).

If a patient has a lower GCS secondary to trauma, there is an increased risk of a worsening patient presentation such as altered awareness, breathing complications, and seizures. Re-assessing a head trauma patient’s GCS is imperative to proper patient management.


Whether a hemorrhagic or occlusive stroke, a patient experiencing a stroke will almost never score a 15 on the Glasgow Coma Scale — unless of course they have a resolved or resolving TIA. Along with a thorough patient exam, using this scale will help you follow any worsening or improving progression of a stroke.

Drug/Alcohol Overdose

Overconsumption of alcohol can result in an expansive list of patient presentations. However, it is important to assess the patient’s LOA thoroughly because there are other disease processes that can mimic intoxicated behavior such as hypoglycemia.

Any patient who ingests a drug — whether it be their usual dose or higher than normal — has the potential to experience side effects that alter their LOA. Having a good overall knowledge of common medications that paramedics encounter, in addition to that of common street drugs, will help you prepare for various patient presentations.

Environmental Emergencies

Outside factors such as heat exposure and hypothermia have the potential to alter a patient’s LOA due to the direct result of temperature exposure on the central nervous system. These patients will require frequent GCS assessments, along with aggressive prehospital stabilization.

Disease Processes

Other disease processes such a renal failure, cancer, adrenal insufficiencies, diabetes, UTIs, symptomatic arrhythmias, COPD and sepsis, can all contribute to an altered LOA and ultimately a lower GCS score.

Conditions That Complicate GCS Interpretation

Language Barriers

Language barriers are a common hurdle in our field and can make it extremely tricky for paramedics to determine a patient’s overall GCS score. Resources such as a family member or translator are helpful but are not always present. Use your best judgement and due diligence for these patients. Assuming their GCS is 15 could be a critical mistake, especially in the case of a stroke.


Pediatrics and younger patients are difficult to assess because they are not likely to answer your questions appropriately or follow your instructions. This is a unique situation that requires a different approach, usually involving a parent.

Outside of the normal GCS rating, there is a pediatric GCS rating that can be used. All three assessment sections are altered to incorporate more age-appropriate assessments with sounds rather than words.

Cognitive Disorders

Age-related disease processes such as dementia and Alzheimer’s disease can make rating a patient’s GCS very difficult.

In a nursing home, it’s ideal to have a staff member present who knows the patient’s baseline which can help you determine their present Glasgow Coma score. If one is not present, a family member should be your next resource if time allows.

Otherwise, your decision making should be focused on what is in the patient’s best interest. And keep in mind that sometimes we are unable to acquire an accurate GCS interpretation no matter how hard we try.

Stay Ahead of the Chaos

A thorough assessment of a patient’s mental status is critical for patient care. Patients who have a Glasgow Coma Scale of three require a hands-on approach that can involve airway management and possibly breathing and circulation support. These patients are often critical and require constant care and reassessments as their presentation can deteriorate fast.

By properly assessing a patient’s GCS and LOA, you establish what the patient’s baseline presentation is early in the call and how you plan to correct any problems. For EMTs and paramedics, staying ahead of chaos is essential, and we can only do that through strong assessment skills, excellent history taking, and thorough patient exams.

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