From the Guidelines
Yes, people can experience visual hallucinations in the ICU at night without having delirium, a phenomenon often called "ICU psychosis" or "ICU syndrome." These hallucinations commonly occur due to several factors including sleep deprivation, constant lighting, frequent interruptions for care, medication effects, and sensory overload or deprivation [ 1 ]. Patients may see shadows, objects, or people that aren't actually present. Management includes ensuring adequate sleep, maintaining day-night cycles by dimming lights at night, orienting patients frequently, minimizing unnecessary noise and interruptions, providing familiar objects from home, and ensuring eyeglasses or hearing aids are available if needed. Certain medications like benzodiazepines, opioids, and anticholinergics can contribute to these experiences, so medication review is important [ 1 ]. While these hallucinations can occur independently, it's crucial to evaluate for delirium as the two can coexist, with delirium being a more serious medical condition requiring prompt intervention. Some key strategies to promote sleep and potentially reduce hallucinations include optimizing patients’ environments, using strategies to control light and noise, clustering patient care activities, and decreasing stimuli at night to protect patients’ sleep cycles [ 1 ]. By addressing sleep deprivation and minimizing environmental disruptions, healthcare providers can help reduce the occurrence of visual hallucinations in ICU patients at night.
From the Research
Visual Hallucinations in ICU
- Visual hallucinations can occur in the absence of delirium, as they are defined as perceptions that occur without a corresponding stimulus 2.
- Hallucinations can involve any of the five senses, including visual, auditory, tactile, gustatory, and olfactory hallucinations 2.
- The presence of visual hallucinations can be associated with various conditions, such as Parkinson's disease, dementia with Lewy bodies, and Charles Bonnet syndrome 3, 4.
ICU Setting
- Delirium is a common condition in ICU patients, and it can be treated with antipsychotics such as haloperidol or atypical antipsychotics like olanzapine 5, 6.
- However, the provided studies do not specifically address the occurrence of visual hallucinations in ICU patients at night without delirium.
- It is essential to note that visual hallucinations can occur in a wide range of human experiences, including in people with visual loss or other neurological conditions 3, 4.
Mechanisms and Treatment
- The mechanisms underlying visual hallucinations are complex and involve changes in neurotransmitters, network dysfunction across the brain, and visual loss 4.
- Treatment approaches to visual hallucinations vary depending on the underlying condition and may include the use of atypical antipsychotics or other medications 4, 6.
- Further research is needed to understand the occurrence of visual hallucinations in ICU patients without delirium and to develop effective treatment strategies for this condition.