What is Sensory and Perceptual Alterations?
Sensory-perceptual alteration happens when there’s a change in the normal pattern of how a person perceives things around them. This could mean that normal sensory experiences like seeing, hearing, touching, smelling, or even how they sense position or movement are heightened, reduced, or distorted. These changes can impact their behavior, their ability to make decisions or solve problems, and may cause irritability, restlessness, poor concentration, changes in mental status or communication abilities, and difficulties focusing. When patients are isolated, the lack of sensory stimulation can lead to anxiety, depression, aggression, hallucinations, and mental instability.
If changes occur in a person’s usual environment, they can end up feeling stressed, especially if it’s not their choice. For instance, when someone faces a lot of sensory input that they can’t handle, it’s often called sensory overload. Usually, our minds can filter out unnecessary information, but certain conditions like a busy emergency department, or illnesses like dementia, can prevent this filtering, leading to sensory overload.
On the other hand, sensory deprivation happens when a person experiences less sensory stimulation than normal. Factors that might lead to these changes include severe sickness, long-term medical conditions, aging, or even changes in their environment due to medical treatments. This often happens when a patient is isolated, like being admitted to the hospital or an isolated ward. In these cases, they might experience a decrease in stimulation and limited social interaction. Other conditions such as hearing loss, vision loss, loss of smell or taste, aging, physical injury, electrolyte imbalance, seizure disorders, mental health issues, and genetic factors can also change the way stimuli are processed, leading to increased or decreased responses to sensory experiences.
What Causes Sensory and Perceptual Alterations?
Certain conditions and factors can result in alterations to our senses and perception. Here are some of them:
Mental Conditions:
Autism: Changes in the sensory-dedicated parts of the brain can cause sensory symptoms in autism. These changes could affect GABAergic signaling, which is crucial for communication between nerve cells.
ADHD (Attention deficit hyperactivity disorder): ADHD can lead to sensory overload because of an inability to ignore unnecessary sensory distractions. This happens due to problems in information processing and perception, making it hard for individuals with ADHD to filter out irrelevant sensory information.
Schizophrenia: This condition entails altered sensory processing and perception, being responsible for the ‘positive’ symptoms (like delusions and hallucinations) of schizophrenia. Noticeable changes in neurotransmitter signaling in the sensory pathway and abnormalities in brain adaptability mechanisms play a role in schizophrenia.
Sensory processing disorder: This neurological condition happens in children when the brain can’t process stimuli accurately, leading to difficulty in processing and judging sensory information. Children may face trouble regulating emotions, paying attention, and adapting responses.
Sleep Disorders:
Altered sleep or lack of sleep can cause a state of confusion, known as delirium, which leads to altered senses and perception.
Delirium in the Intensive Care Unit:
Critically ill patients in intensive care are at a higher risk of delirium. Sensory and perceptual alterations can occur due to the patient’s own health condition, critical illnesses, and environmental factors like sleep deprivation, sensory deprivation, immobilization, and social isolation.
Disturbed sleep in the ICU may be caused by various factors, including the use of a ventilator, medication, continuous exposure to light disrupting the circadian rhythm, noise from equipment, conversations among health care staff or patients and patient care activities. Long-term or repeated sleep deprivation can lead to delirium, prolonged cognitive dysfunction, a decrease in quality of life, and impaired immune function.
Isolating patients can yield negative impacts on mood, increasing the risk of conditions like depression, anxiety, hostility, and fear, which can lead to feelings of losing control. Older patients with cognitive disorders are more likely to experience delirium when isolated.
Neurological Disorders:
Many neurological disorders and syndromes can cause changes in behavior and cognitive functioning due to altered brain function. These changes can be acute, relating to trauma, metabolic and electrolyte imbalances, medication, infections, or vascular changes, or they could be gradual due to inherited disorders, neurodegenerative diseases, cancers, or structural disorders.
In Alzheimer’s disease, sensory visual impairments are common due to disturbances in the cortical areas of the brain. This impacts visual skills like visual attention, visual memory, emotional perception, object and face perception, visual learning, and reading.
In Parkinson’s disease, the progressive loss of cells that produce dopamine in the retina and other visual areas leads to deficits in visual perception. This loss of dopamine impacts the function of retinal ganglion cells, which are essential for vision.
Patients with seizure disorders like epilepsy can have alterations in all five senses due to the disease’s broad effects on various neural networks. For example, people with temporal lobe epilepsy often experience difficulties with smelling.
Visual and Hearing Problems:
In older adults, common causes of visual dysfunction include age-related changes in the eye, diabetic retinopathy, glaucoma, cataracts, age-related maculopathy, and Bonnet syndrome which can cause visual hallucinations. Hearing loss can result in auditory hallucinations, such as Anton’s syndrome.
Electrolyte Imbalances:
Altered sensorium can occur due to electrolyte imbalances, especially low sodium and calcium levels, which can induce delirium in the elderly.
Substance Abuse:
Alcohol or drug use can lead to cognitive impairments, which in turn can alter sensory and perceptual experiences.
Chronic Medical Problems:
Conditions like liver failure, kidney failure, and AIDS can cause changes in perception and sensation. Other causes can include high fever, surgery, terminal illnesses, a mismatch between ventilation and circulation in the lungs, multiple medications, and certain conditions in elderly patients.
Risk Factors and Frequency for Sensory and Perceptual Alterations
Delirium is a condition that can affect between 3% and 42% of people admitted to the hospital. It’s even more common in patients who are seriously ill, affecting up to 80%. The number of people affected can vary depending on what causes the delirium and other factors. Additionally, as many as 12% of people in the general population might experience hallucinations, which can significantly impact their daily lives.
Signs and Symptoms of Sensory and Perceptual Alterations
People may suffer from sensory and perceptual changes due to various risk factors. These changes can occur in certain situations or surroundings and may even happen out of the blue. Different stimuli or environmental factors can also trigger these changes. When patients are placed in unfamiliar settings like a hospital room, these sensory and perceptual changes might feel more intense.
The signs that indicate whether a person is experiencing these changes can differ. Sometimes the person might seem ‘out of sorts’ or not aware of their surroundings or time. They might seem confused, easily irritated, have trouble focusing or solving problems. They might even have difficulties communicating. In some cases, hallucinations (seeing, hearing, or feeling things that are not there) may also occur. Based on the nature of these perception changes, certain tests related to the brain and senses might reveal abnormalities. However, aside from these specific signs, other general health checks may show normal or varied results based on the individual’s overall health condition.
Testing for Sensory and Perceptual Alterations
When doctors are trying to determine whether a patient in the Intensive Care Unit (ICU) is experiencing delirium, they often use validated assessment tools. Two examples of these are the Confusion Assessment Method for the ICU (CAM-ICU) and the Intensive Care Delirium Screening Checklist (ICDSC).
In addition to these assessment tools, other tests may be necessary to confirm the diagnosis. An electrocardiogram, often called an EKG or ECG, is a test that measures the electrical activity of the heartbeat. An echocardiogram is a type of ultrasound that lets doctors see how the heart is beating and pumping blood. Lab tests involve analysing samples such as blood or urine to detect medical conditions. Cerebrospinal fluid studies involve analyzing fluid from the spine for various conditions. An electroencephalogram or EEG measures electrical activity in the brain using small sensors attached to your scalp.
Other imaging tests, such as a chest X-ray or a CT scan of the head, might also be necessary. A chest X-ray creates images of the heart, lungs, blood vessels, airways, and the bones of the chest and spine. A computed tomography scan, more commonly known as just a CT scan, combines a series of X-ray images taken from different angles around your body, and uses computer processing to create cross-sectional images of the bones, blood vessels and soft tissues inside your body. This can help doctors to visualise and detect any abnormalities or issues which may be causing the delirium in the patient.
Treatment Options for Sensory and Perceptual Alterations
The safety of patients is always the main priority. If a patient starts behaving in a way that suggests they are having some sensory or perceptual problems, it can not only make them feel distressed but also potentially put them at risk of hurting themselves or others. That’s why it’s important to figure out what might be causing this and how best to help them.
One helpful approach can be to regularly remind the patient of the current time, where they are, and who they are. You could do this by having a chat about what’s going on in the world, what the weather’s like, or asking about their hobbies or past experiences. It’s also beneficial to create a calm and quiet environment for the patient, avoiding overly bright lights or loud noises.
If the patient has issues with their vision, you could offer them glasses or reading materials with large print or even braille. When talking to them, try to be on the same eye level and within their field of vision. Make sure their surroundings are tidy and let them know where their belongings are. Similarly, for patients with hearing issues, make sure they have their hearing aids and that the environment is as quiet as possible. You might also need to communicate through writing or sign language.
If a patient is experiencing delirium, which is a sort of confusion often seen in people in intensive care units (ICUs), a combination of different treatments can be used. However, medications used to treat delirium have been shown to have mixed results, and some studies even suggest they could lead to worse outcomes. Therefore, using medicine to manage delirium in the ICU is not generally advised.
There are various non-drug strategies that can help prevent and manage delirium. These might include the use of earplugs and eye masks to help the patient sleep, controlling the noise levels in the environment, light therapy, activities that engage the brain, and regular review of their medications.
Getting enough good quality sleep is crucial in preventing delirium in ICU patients. Reducing the amount of noise and light in a patient’s surroundings with earplugs and eye masks has been shown to improve sleep and reduce the risk of delirium.
If a patient is hearing, seeing, smelling, or tasting things that aren’t there, it could be due to mental health conditions like schizophrenia, bipolar disorder, post-traumatic stress, and dementia, sleep disorders, or substance misuse. It’s important to have a thorough assessment to figure out the cause. The appropriate medications along with cognitive-behavioral therapy sessions or visits with a psychotherapist can then be used to manage these conditions.
What else can Sensory and Perceptual Alterations be?
There are many different conditions that can cause changes in how we perceive our senses. Here are some possibilities:
- Problems with cognitive function
- Having a stroke
- Using many different medications at the same time
- Using medications that block acetylcholine, a neurotransmitter in your body
- Using drugs that affect your mood and mind
- Being dehydrated or not getting enough nutrients
- Having multiple health issues at the same time, including liver or kidney failure
- Having an infection throughout your body (sepsis) or another infectious disease
- Being terminally ill
- Having too much acid in your body fluids (metabolic acidosis)
- Being constipated
- Not getting enough sleep
- Being depressed
- Feeling lonely or not having many social connections
- Having temporary imbalances in electrolytes, which are minerals in your body that have an electric charge
- Having a type of seizure called a generalized tonic-clonic seizure
- Having problems with your vision or hearing
What to expect with Sensory and Perceptual Alterations
The outcome of treatment relies on what’s causing changes to a person’s senses and perception. The most important steps in managing these changes are recognizing them early and trying to prevent any harm or discomfort to the patient.
Possible Complications When Diagnosed with Sensory and Perceptual Alterations
The primary issue associated with this situation is placing the patient in a stressful and potentially harmful environment. Changes in the environment can escalate the patient’s stress levels and can put them in danger of falls and injuries. Additionally, the patient may pose a risk to themselves or others due to aggressive actions. It’s crucial to thoroughly evaluate the situational cause to aid the patient and help prevent additional distress or harm.
Main Risks:
- Patient stress escalation
- Potential for falls
- Possible injuries
- Patient could be a danger to themselves or others
- Aggressive behaviours
Preventing Sensory and Perceptual Alterations
If a patient is isolated as part of their treatment, this can sometimes lead to feelings of loneliness and anxiety. Helping patients to comprehend why isolation is sometimes needed and what they can expect from the experience can help them to deal with these feelings more effectively. By preparing them emotionally and keeping them informed, we can lessen feelings of worry and distress and help them cope better with the situation.
When a patient is in the Intensive Care Unit (ICU), it’s crucial to try and prevent a state of confusion known as ‘delirium’. One way to do this is by involving family members in the patient’s care. Open, regular communication between family members and healthcare professionals is very important. It can be really helpful if family members bring familiar personal items for the patient, such as their eyeglasses or favorite pillow. These items can make the environment feel less foreign, easier to understand, and keep the patient’s mind active.
It’s also highly beneficial for family members to understand what delirium looks like, in terms of signs and symptoms. That way, they can recognize it early if it starts to develop and alert the healthcare professionals, who can manage the condition more promptly.
