Lighter Sedation for Elderly Surgery Patients May
Reduce Risk Of Confusion, Disorientation
Elderly seldom afraid of dying… they just want to
know if they’ll return to the same mental and physical level as before
surgery
Jan. 24, 2010- A common complication following
surgery in senior citizens is postoperative delirium, a state of
confusion that can lead to long-term health problems and cause some
elderly patients to complain that they “never felt the same” again after
an operation. But a new study by Johns Hopkins researchers suggests that
simply limiting the depth of sedation during procedures could safely cut
the risk of postoperative delirium by 50 percent.
“Merely by adjusting how a person is sedated can
have a profound effect on their postoperative cognitive state,” says
study leader
Frederick E. Sieber, M.D., an associate professor of anesthesia at
the Johns Hopkins University School of Medicine and director of
anesthesiology at Johns Hopkins Bayview Medical Center.
Sieber says propofol, a short-acting anesthetic
commonly used to induce anesthesia and keep patients asleep, and similar
anesthetics may not behave as the clear “on/off phenomena” they were
long thought to be, with effects disappearing as soon as the drugs are
withdrawn.
“What our study indicates,” he says, “is that there
may be lingering effects of anesthesia that heretofore may not have been
appreciated, especially in the elderly.”
In a double-blind randomized study of 114 seniors
undergoing hip fracture repair at Johns Hopkins Bayview Medical Center,
patients first received spinal block anesthesia and were then either
lightly sedated with propofol or more deeply sedated with the same
medication. The prevalence of postoperative delirium was significantly
lower in the group that was lightly sedated.
The findings, which appear in the January issue of
Mayo Clinic Proceedings, suggest that one incident of delirium could be
prevented for every 4.7 patients treated with light sedation. The
average age of the patients in the study was 81.
In addition to decreasing the prevalence of
postoperative delirium in the study’s patients, lighter sedation was
associated with a one-day reduction in the duration of delirium in those
patients who still emerged from surgery confused and disoriented.
Deeply sedated patients were unresponsive during
surgery, while the lightly sedated patients were able to respond to
questions. Researchers judged how deeply sedated the patient became by
placing an EEG monitor on the patient’s forehead.
The prevalence of delirium in elderly patients
after hip fracture repair surgery has been estimated, in various
studies, at between 16 percent and 62 percent.
While it usually resolves after 48 hours, delirium
can persist and is associated with poor functional recovery, increased
length of hospital stay, higher costs and a greater likelihood of
placement in an assisted living facility after surgery. It may even
increase the risk of death in the first year after surgery, according to
Sieber.
Surgeons and anesthesiologists for years have
struggled with the question of whether the postoperative delirium they
see in their elderly patients is caused by the anesthesia they are using
during surgery.
Sieber and his colleagues hypothesize that some
drug-induced alteration of brain activity is increasing the cognitive
dysfunction in those who are more deeply sedated, though the exact
mechanism remains uncertain.
Sieber says it is unclear whether the results would
be the same with different sedative drugs or with patients who have more
serious cognitive impairment prior to surgery. The patients in this
study were either cognitively intact or had mild to moderate cognitive
problems before having hip surgery.
Sieber says reducing the depth of sedation is a
simple and cost-effective way to attack this problem, which is seen more
often as the population continues to age. He hopes this study will
change the practices of fellow anesthesiologists and help reduce the
number of patients who suffer from postoperative delirium.
“Elderly patients, when they come to surgery, often
are not afraid of dying. They want to know if they’ll return to the same
functional level - mental as well as physical - as before surgery,”
Sieber says. “That’s what their real worries are.”
In addition to Sieber, other Johns Hopkins
researchers on the study were Khwaja J. Zakriya, M.D.; Allan Gottschalk,
M.D., Ph.D.; Mary-Rita Blute, R.N.; Hochang B. Lee, M.D.; Paul B.
Rosenberg, M.D.; and Simon C. Mears, M.D., Ph.D.
Keep up with the latest news for senior citizens, baby
boomers
Jan. 24, 2010- A common complication following
surgery in senior citizens is postoperative delirium, a state of
confusion that can lead to long-term health problems and cause some
elderly patients to complain that they “never felt the same” again after
an operation. But a new study by Johns Hopkins researchers suggests that
simply limiting the depth of sedation during procedures could safely cut
the risk of postoperative delirium by 50 percent.