By Thomas Goldsmith
Conversation after an older person’s surgery sometimes goes like this: “Grandpa has just not been the same since his operation — he often forgets words and can’t complete simple tasks.”
Doctors have long believed that cognitive decline often follows surgery — more than half of people who have open-heart surgery go through it — but its precise nature remains under study. Duke neuropsychologist Jeffrey Browndyke is part of an international group that has been working toward a standard definition for postoperative cognitive disorder, or POCD, both to improve treatment and to merit its inclusion in the influential DSM-5, the manual that helps behavioral health practitioners make accurate diagnoses.
“Our hope is that by better describing individuals who are experiencing a cognitive decline after surgery, we can hone in on certain areas of postoperative cognition and behavior that might be amenable to specific types of treatment,” Browndyke said in an interview.
The problems posed by this decline in clear thinking and inability to do day-to-day things are significant. POCD creates more risk of long-term issues for people older than 60, according to a paper by Duke anesthesiologist Dr. Terri Monk and others. In addition, this study shows that people who experience POCD are more likely to die in the first year after an operation than others.
The persistence of POCD isn’t universally accepted, with detractors noting that many people believed to be affected have previous evidence of cognitive decline.
Browndyke says most people who experience this sort of decline do recover from it in time.
However, research with abdominal surgery patients has shown that a team approach to the problem used at Duke and the Durham VA leads to earlier discharge and fewer hospital readmissions. That’s a huge change in an era in which the Centers for Medicare and Medicaid Services penalizes hospitals hundreds of millions of dollars annually for excessive return stays by patients.
The new nomenclature for POCD that Browndyke has worked on is to appear in scholarly papers in domestic and international medical journals as soon as this month. It divides patients with cognitive impairment after surgery into two groups, those with mild neurocognitive disorder (POCD) and those with major neurocognitive disorder (POCD). These are designed as possible diagnoses for insertion into the DSM-5.
“A multifactorial problem”
“With mild neurocognitive disorder, we see some subjective complaints of cognitive issues, but with general preservation of functional skills, so they are still active in the community, they are still getting groceries, still driving,” Browndyke explained. “With major neurocognitive disorder, they have significant change in cognition and their functional abilities.”
Dr. Miles Berger, assistant professor of anesthesiology at Duke University School of Medicine, told Kaiser Health News: “There is no single presentation for POCD. Different patients are affected in different ways.”
Researchers also differ on their beliefs in the causes of cognitive loss after surgery.
“If I were a betting man, I would say that POCD is a multifactorial problem, meaning that if you put your finger in the dam to fix one part of it, it’s going to flood out somewhere else,” Browndyke said. “It’s likely a combination of neuro-inflammatory response, the effects of surgery, the effects of anesthesia, the reorganization of brain networks — there’s a multitude of things that could be contributing to it.”
Browndyke’s specific research involves functional networks of the brain. It appears that the brain networks don’t work well together in POCD, he said. Confusion and memory loss can result.[sponsor]
At Duke’s POSH program, for Perioperative Optimization of Senior Health, teams of professionals from surgeons to clergy work to prepare older patients for safe surgery and smooth recovery. One method for attempting to ward off POCD is to make sure patients are in the best possible shape medically ahead of surgery, in areas including mobility and nutrition, said Dr. Kahli Zietlow, a Duke internal medicine specialist.
“We spend a lot of time looking at medications; we try to take people off medications that may be problematic,” Zietlow said. “It’s also important for them to see a friendly face after surgery.”
Potential problems probed
The diverse POSH teams include surgeons, geriatricians, anesthesiologists, physical and operational therapists, neuropsychologists, dieticians and the chapel staff. The teams work with patients both at Duke Hospital and at the associated Durham Veterans Administration Medical Center.
“The idea here is for us to identify these potential risks for delirium and postoperative cognitive dysfunction before the person even goes to surgery,” said Browndyke, who’s affiliated with the POSH Center. “A surgeon will make a referral to the POSH clinic. They think their patient may have cognitive issues, or the surgery may be complicated or the individual is particularly frail and they think they may be at risk for delirium or POCD.”
Dr. Sandhya Lagoo-Deenadayalan is an associate professor of surgery and a founder of POSH along with Dr. Mitchell Heflin. Lagoo-Deenadayalan said the complexity of POCD demands attention from a range of specialists.
“When the geriatrician sees the patient and evaluates the patient, they are able to uncover the problem with cognition,” she said. “Just talking to them, you might not be able to diagnose that they have these problems. Surgery is a stressor and it uncovers the problem.”
The complexity of POCD means, Browndyke said, that it’s appropriate for researchers to operationalize the disorder, or define it in terms that can more easily be measured.
“I think it’s going to generate a lot of interest,” he said of the coming publications. “It may actually generate some controversy as well, who knows? With all this information getting out there will be grounds for it.”