If you asked your colleagues to define postoperative delirium and the symptoms to look out for, do you think they could answer you with confidence? Believe it or not, the condition is widely misdiagnosed because its symptoms can present in a variety of ways. What makes it so tricky to diagnose is there are several types of delirium:
- Hyperactive delirium. The most easily recognized and common form with symptoms including hostile behavior, such as climbing out of bed and pulling on oxygen tubes and IV lines.
- Hypoactive delirium. The hardest form of delirium to diagnose because the patient is acting withdrawn and lethargic.
- Mixed delirium. This form is displayed as a constant vacillation between hyperactive and hypoactive delirium.
There is no definitive answer as to what causes post-op delirium, but older patients are most at risk because of a loss of physiological reserves combined with cognitive impairments. There are also many clinical factors that can contribute to delirium such as an infection, a large volume of blood loss during surgery or even a long procedure. Cancer patients who undergo robotic surgery are also at increased risk for developing the disorder.
Patients who receive general anesthesia experience slightly more cognitive impairment than those receiving regional anesthesia. The thought process is that general anesthesia renders the patient unconscious and decreases some of the body’s physiological responses, thus rendering an inability to regulate blood pressure and heart rate, which combine to decrease the amount of blood flow to the brain.