BACKGROUND

Delirium is a common complication in elderly hospitalized patients. It prolongs the length of hospital stay, raises costs, increases the workload of the nursing staff, and may necessitate transfer of the patient to a nursing home. The risk of postoperative delirium is particularly high in elderly patients with pre-existing cognitive deficits.

METHODS

In an open study, we systematically assessed the frequency of postoperative delirium in patients over age 70 on two surgical wards of a general hospital. In a six-month "prevalence phase," from March to August 2011, we counted the number of patients with postoperative delirium, but did not initiate any intervention. Thereafter, in a ten-month "intervention phase" from September 2011 to June 2012, a nurse with special training in the management of delirium carried out an intervention involving component measures of the Hospital Elder Life Program (HELP) on one of the two wards, with the aim of preventing postoperative delirium. The patients on the other ward served as a control group.

RESULTS

In the prevalence phase, 20.2% of all patients developed postoperative delirium (95% confidence interval [CI], 14.6-26.4). In the intervention phase, postoperative delirium arose in 20.8% (95% CI, 11.3-32.1) of the patients on the ward with no specific interventions, but in only 4.9% (95% CI, 0.0-11.5) of those on the ward where the intervention was carried out. The difference was presumably due to the measures initiated by the specially trained nurse, including validation, improvement of sleep, cognitive activation, early mobilization, improved sensory stimulation, and improved nutritional and fluid intake. Important predictors of postoperative delirium included a low score on the Mini-Mental State Examination, advanced age, and preoperative infection.

CONCLUSION

The frequency of postoperative delirium in elderly patients with cognitive deficits can be lowered with nursing measures carried out by a specially trained nurse, close postoperative supervision, and cognitive activation.