Because PCD has a multifactorial cause, many risks factors may contribute to
its development. Preoperatively, patients who are
elderly10,85,94 or those who have poor preoperative
cognitive10,85,94,100 or functional
status94,101 are at higher risk for developing PCD. The
presence of a history of alcohol abuse or marked abnormalities in
preoperative sodium, potassium, or glucose levels may also be predictors for
the development of PCD.94,102–104 Intraoperatively,
certain types of surgical procedures (eg, cardiac surgery with
cardiopulmonary bypass,105 aortic aneurysm
repair,94 and orthopedic procedures in elderly
patients101,106,107) are associated with higher rates of
PCD. Cerebral hypoperfusion or abnormalities in intraoperative glucose and
hematocrit levels do not appear to correlate with
PCD.108,109 The correlation of sustained and profound
hypotension, hypoglycemia, anemia, or hypoxia to the development of PCD is
unclear. A longer duration of surgery and anesthesia is associated with an
increase in the incidence of PCD.84,110 Postoperatively,
the use of anticholinergic drugs, meperidine, and benzodiazepines, is
associated with the development of PCD.10,86,111
Complications, such as postoperative infections and respiratory
complications, are also associated with the development of
PCD.84 Finally, increased levels of postoperative pain are
associated with a higher incidence of PCD.11,112,113