A lot of drugs and not much oxygen: Is the cocktail responsible for delirium?

We read with great interest the article by Arenson and colleagues that analyzed the risk factors for postoperative delirium, with particular reference to the influence of intensive care unit environment, in a large study population undergoing cardiac surgery. In their multivariate analysis, postoperative delirium was significantly associated with preoperative (eg, age, preadmission use of benzodiazepine), intraoperative (eg, combined coronary artery bypass grafting and valve surgery), and postoperative (eg, stroke or transient ischemic attack, mechanical ventilation >24 hours, blood transfusion, postoperative renal insufficiency) risk factors. These findings confirm the multifactorial triggers and causes of this neurologic complication and may contribute to its prevention and better management of this phenomenon. In particular, Arenson and colleagues found an influence of intensive care environment in patients younger than 65 years. We agree with Inouye that a substantial proportion of delirium is preventable through appropriate care and attention. In a study of our group that used near-infrared spectroscopy for cerebral saturation monitoring, a higher incidence of postoperative delirium was observed in patients with a bispectral index reduction more than 25% from baseline. Near-infrared spectroscopy is routinely used in many centers as a monitor for depth of anesthesia. Regardless of the causes of cerebral oxygen desaturation (excessive anesthetic depth, bypass flow set too...
Source: The Journal of Thoracic and Cardiovascular Surgery - Category: Cardiovascular & Thoracic Surgery Authors: Tags: Letters to the Editor Source Type: research