Research published in the June issue of Anesthesiology
analyzes the causes of complications such as stroke and cognitive impairment after surgery. While one study identifies the specific risk factors associated with postoperative stroke, the other explores the role anesthesia plays in the cognitive decline of elderly patients following surgery. Risk of Postoperative Stroke
Stroke is a leading cause of death in the U.S. It is known to occur after surgery, including in surgeries that do not involve the heart or brain. Postoperative stroke is relatively understudied, especially in low-risk populations; the recent study in Anesthesiology
was one of the largest and most comprehensive to analyze the incidence, predictors and outcomes associated with the complication.
Researchers at the University of Michigan used a national database to study the incidence, predictors and outcomes associated with postoperative stroke. The records of more than 500,000 non-cardiac and non-neurologic patients were analyzed to determine the frequency of stroke, as well as which patients are most at risk.
“Our study was able to identify the numerous risk factors of postoperative stroke in patients undergoing non-cardiac surgery,” said lead study author George A. Mashour, M.D., Ph.D. “Some of the factors included myocardial infarction, acute renal failure, past history of stroke, dialysis and hypertension. We also found that stroke was associated with an eight-fold increase in postoperative mortality within 30 days.” More importantly, the authors developed a “risk index classification” to help guide clinicians as to who is at highest risk of postoperative stroke. Postsurgical Cognitive Impairment
Elderly patients receive anesthesia for a variety of surgical procedures, many of whom experience cognitive decline after surgery. In an effort to better understand the normal course of deterioration and if anesthesia and surgery worsens cognitive decline in elderly surgical patients, a new study in Anesthesiology
evaluated patients undergoing total hip joint replacement for preoperative Mild Cognitive Impairment, a type of cognitive decline known to progress to Alzheimer’s Disease.
One hundred and fifty two patients over the age of 60 years underwent assessment, including neuropsychological testing one week before surgery at St. Vincent’s Hospital in Melbourne, Australia. Test results were compared with published norms and revealed that patients about to undergo hip joint replacement performed worse compared to normative data on five of seven neuropsychological tests. Furthermore, Mild Cognitive Impairment was more prevalent than anticipated.
“As baby boomers continue to age, it is important we determine whether anesthesia plays a role in cognitive decline,” said lead corresponding author Brendan S. Silbert, M.D. “Additional research must go one step further and compare the changes in cognition after anesthesia and surgery with the changes in cognition in population studies.”
For more information, visit the Anesthesiology
website at www.anesthesiology.org