One should automatically suspect delirium in the presence of visual, olfactory, or tactile hallucinations. At some point, orientation is usually impaired. Short-term memory can also be impaired. Less commonly, recent and remote memory are impaired. These short-term memory and orientation deficits may also indicate dementia, but should not be impaired in other psychoses.3 Patients often will misidentify persons in their environment.
Thinking processes can be very tangential or can be blocked.
At MCL, we devised a protocol that includes a mnemonic to help recognize the most common signs and symptoms. We recommend obtaining both neurology and psychiatry consultations for the work-up. A detailed physical examination should pay special attention to infections, focal neurological deficits, metabolic disease, withdrawal states, and trauma. A chest x-ray film, complete blood count, blood chemistry, CT or MRI of the head, possibly an LP, urinalysis, drug screen, blood alcohol level, ECG, thyroid function tests, ammonia level, arterial blood gases, and EEG should also be done. HIV testing, Vitamin B12 levels, lead, mercury, and magnesium levels may be useful.