The effects of postoperative pain and its management on postoperative cognitive dysfunction.

To determine risks for postoperative cognitive dysfunction (POCD), the authors conducted a prospective cohort study of 225 patients > or = 65 years of age undergoing noncardiac surgery. Cognitive testing using the Word List, Verbal Fluency, and Digit Symbol tests was conducted for each patient preoperatively and 1 and 2 days postoperatively in patients without postoperative delirium. POCD was defined as meeting statistical criteria for decline from the patient's preoperative performance levels on at least two of the three cognitive tests. Multivariate logistic regression analysis determined the association between pain and postoperative analgesia with POCD after controlling for demographics, comorbidities, preoperative level of cognitive and daily functioning, preoperative medications, duration and type of anesthesia, and adverse events. Patients were on average 72 years old and 13% of patients experienced POCD on day 1, 7% on day 2, and 15% had POCD on either day 1 or day 2 after the surgery. Multivariate regression analyses revealed that only postoperative analgesia was associated with the development of POCD. Compared with those receiving postoperative analgesia through a patient-controlled analgesia device that administered opioids intravenously, those who received postoperative analgesia orally were at significantly lower risk for the development of POCD (odds ratio: 0.22; 95% confidence interval: 0.06-0.80; Wald chi-square = 5.36, df = 1, p = 0.02). Older patients undergoing noncardiac surgery who are not delirious can experience significant declines in cognitive functioning postoperatively. Those at least risk of experiencing POCD were those who received postoperative analgesia orally.

Postoperative delirium: the importance of pain and pain management.

Postoperative delirium is common in geriatric patients. Few studies have examined events in the postoperative period that may contribute to the occurrence of postoperative delirium. We hypothesized that postoperative delirium is related to postoperative pain and/or pain management strategy. Patients aged > or =65 years who were scheduled for major noncardiac surgery were studied. A structured interview was conducted preoperatively and for the first 3 postoperative days to determine the presence of delirium using the Confusion Assessment Method. The method of postoperative pain management, as well as pre- and postoperative medications for the first 3 days, was collected. Pre- and postoperative pain at rest and with movement was recorded using the Visual Analog Scale. Three hundred thirty-three patients, with a mean age of 74 +/- 6 years, were studied. After surgery, 46% of patients developed postoperative delirium. By multivariate logistic regression, age (odds ratio [OR], 2.5; 95% confidence interval [CI] 1.5 to 4.2), moderate (OR, 2.2; 95% CI 1.2 to 4.0) and severe (OR, 3.7; 95% CI 1.5 to 9.0) preoperative resting pain, and increase in level of pain from baseline to postoperative day one (OR, 1.1; 95% CI 1.01 to 1.2) were independently associated with a greater risk for the development of postoperative delirium. In contrast, patients who used oral opioid analgesics as their sole means of postoperative pain control were at decreased risk of developing delirium in comparison with those who used opioid analgesics via IV patient-controlled analgesia technique (OR, 0.4; 95% CI 0.2 to 0.7). These results validate our hypothesis that pain and pain management strategies are important factors related to the development of postoperative delirium in elderly patients.

Are preoperative depressive symptoms associated with postoperative delirium in geriatric surgical patients?

BACKGROUND: Delirium is common in older surgical patients and predicts negative health outcomes. Whether depressive symptoms are prevalent and predict the development of postoperative delirium in elderly surgical patients has not been investigated. Our study aimed to examine the prevalence and prognostic importance of preoperative depressive symptoms in older surgical patients. METHODS: Patients at least 65 years of age who were scheduled for major noncardiac surgery were recruited. Preoperatively, patients were screened for symptoms of depression using the 15-point Geriatric Depression Scale (GDS). Postoperative delirium was measured using the Confusion Assessment Method. The associations between covariates and preoperative depression, and postoperative delirium were determined by multivariate logistic regression. RESULTS: In the 219 patients studied, the mean age was 73.6 +/- 6 years, 12% of patients reported six or more depressive symptoms, and 32% reported three to five depressive symptoms. By multivariate logistic regression, patient characteristics associated with six or more symptoms of depression included <12 years of education, moderate to severe limitation in functional status, and drinking more than two alcoholic beverages per day. Postoperatively, 46% of patients developed delirium. Patients with a greater number of preoperative depressive symptoms were more likely to develop postoperative delirium (p =.048) and experience a longer duration of postoperative delirium (p =.027). Even after adjusting for covariates associated with depression and postoperative delirium--including age, educational level, functional status, and preoperative alcohol use--patients with more than six preoperative depressive symptoms were still significantly more likely to have a longer duration of postoperative delirium than did those patients with fewer than two depressive symptoms (odds ratio = 2.69, confidence interval = 1.04-6.93). CONCLUSION: Preoperative screening for the presence of depressive symptoms can be performed easily in elderly patients, and yields useful prognostic information relating to postoperative delirium.