COMPARISON OF INCIDENCE RATE OF POST OPERATIVE DELIRIUM BETWEEN PATIENTS WITH OPEN HEART SURGERY AND GENERAL SURGERY - AHWAZ GOLESTAN HOSPITAL 1999

Delirium is an under-diagnosed cognitive disorder with poor prognosis. In many articles the reported incidence rate of delirium following cardiac surgery varies from 2 to 57 percent. Recently the rate of delirium after cardiotomy has been reported to be more than 90 percent whereas this rate is approximately 10-15 percent in general surgical wards. This is the first comparative study carried out in Ahwaz Golestan hospital in order to compare the incidence rate of postoperative delirium between patients with open-heart surgery and general surgery. Thirty patients with age range of 40.5-63 years old were selected for each group. The sampling method was easy sampling. A questionnaire was provided containing of patients’ personal data and the type of surgery, history and mental status examination based on DSM IV. Memory and attention was measured based on cognitive screen tests. Patients were examined by psychiatry assistant one day before surgery and two to five days after surgery during evening and early morning hours. In order to compare incidence rate of delirium between two groups we used Fisher Exact Test. Three patients after open-heart surgery and 1 patient after general surgery experienced delirium. Statistical analysis did not indicate significant difference between incidence rate of postoperative delirium between these groups. This rate in open-heart surgery was 10 percent and in general surgery was 3.3 percent that is lower than previous studies. This difference may be due to lower age of patients, lower rate of alcohol and substance use, difference in type of surgery, criteria for diagnostic of delirium and use of advanced cardiac surgery and anesthetizing methods. Moreover, religious believes in our culture that diminishes preoperative anxiety may be another reason of the lower incidence in the rate of delirium.