NursingCenter Blog

Assessing Level of Consciousness

Oct 25 2022 by Myrna Buiser Schnur, MSN, RN

As a nurse, the first thing we often do when we walk into a patient’s room is assess the patient’s mental status and level of consciousness. We immediately observe whether the patient is awake and alert. If awake, we’ll ask them some simple questions such as their name, date and why they are in the hospital. This “small talk” will help us determine if the patient can respond appropriately, if they are focused, or confused. If the patient does not or cannot respond to questions, you should continue your neurologic assessment with a more indepth evaluation of the patient’s level of consciousness.

Level of Consciousness (Bickley et al., 2021; Hinkle, 2021)

Level of consciousness (LOC) is a sensitive indicator of neurologic function and is typically assessed based on the Glascow Coma Scale including eye opening, verbal response, and motor response. Document your patient’s LOC based on the following categories.

Alert: the patient opens their eyes spontaneously, looks at you when spoken to in a normal voice, responds appropriately to stimuli, and movements are purposeful.
Lethargic: the patient appears drowsy but opens their eyes to loud verbal stimuli and looks at you, responds to questions, and then falls back asleep.
Obtundation: the patient opens their eyes with tactile stimuli and looks at you but responds to you slowly and may be confused.
Stupor: the patient awakens only after painful stimuli is applied (i.e., applying pressure to the nailbed). The patient’s verbal responses are slow or absent. The patient will fall into an unresponsive state when the stimuli stops.
Coma: patient is unarouseable and their eyes remain closed. There are no purposeful responses to internal or external stimuli. However, nonpurposeful responses to painful stimuli and brain stem reflexes may still be present.

Altered LOC (Hinkle, 2021)

There are several underlying conditions that can cause an altered level of consciousness, including neurologic (head injury, stroke), toxicologic (drug overdose, alcohol intoxication), or metabolic disorders (hepatic or kidney injury, diabetic ketoacidosis). Early signs of an altered LOC include behavioral changes such as restlessness or anxiety. As the patient’s LOC declines, changes will occur in the pupils, eye opening, verbal responses, and motor responses. Specifically, the pupillary light reflexes become sluggish. If the patient progresses to coma, the pupils may become fixed and non-reactive to light and neurologic disease is suspected as the cause. If the patient is comatose but pupillary light reflexes are intact, the cause may be metabolic or toxicologic.

Diagnostic tests are needed to help determine the cause of significant changes in LOC. Tests may include a computed tomography (CT) scan, perfusion CT, magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), or electroencephalography (EEG). Several common laboratory tests should be obtained: blood glucose, electrolytes, serum ammonia, liver function tests, blood urea nitrogen (BUN), serum osmolality, calcium, partial thromboplastin and prothrombin times. Additional tests may include serum ketones, alcohol and drug concentrations, and arterial blood gases.

Nursing Management

As you care for a patient with an altered or decreasing LOC, remember that maintaining the patient’s airway remains the priority. Monitor the patient’s blood pressure and heart rate to ensure adequate perfusion to the brain. Insert an intravenous (IV) catheter to administer IV fluids and medications as needed and initiate nutritional support. Determine and treat the underlying cause.