Multidisciplinary teams conducting daily rounds in intensive care units will typically work their way down hallways, going from one patient to the next based on spatial proximity.
According to a recent multi-center study led by researchers at Vanderbilt University Medical Center and published in Critical Care Medicine, if teams instead start with the sickest patient and proceed to others based on decreasing patient acuity, something good happens.
“Our study finds a significantly greater depletion of attention reserves with conventional rounding, compared to teams that adopted an acuity-based patient order for rounds,” said Merrick Miles, MD, assistant professor of Anesthesiology, who co-led the study with Joseph Schlesinger II, MD, associate professor of Anesthesiology at VUMC and adjunct professor of Electrical and Computer Engineering at McGill University in Montréal, Canada.
When ICU teams round, it’s been shown that they tend to spend a bit less time with each successive patient. One study showed an average eight minutes less time spent on the last patient compared to the first.
“That previous finding, and the prospect that attentional reserves might diminish as teams go from patient to patient, are reason alone to consider switching to patient acuity as a basis for rounding order,” Schlesinger said. “With this new study, using psychometrics, we begin to pin down the cognitive benefits for teams that adopt acuity-based rounding.”
Researchers followed ICU teams at VUMC and the University of Pennsylvania Medical Center in Philadelphia. They tested so-called reactive inhibition — considered as a proxy for cognitive control and attentional reserves — in physicians and advanced practice nurses immediately before and after rounds using a standard method called a stop signal task.
Here’s how stop signal tasks work: a white arrow appears on a computer screen pointing left or right, and without delay the subject is to press the corresponding keyboard arrow. Repeated trials yield the subject’s average reaction time for accurate responses.
A second round of trials resembles the first, except that in a subset of instances the white arrow turns blue within milliseconds and the subject is to halt his or her go reaction and refrain from pressing the keyboard.
The more depleted a subject’s cognitive control and attentional resources have become, the more time he or she will need to successfully exert reactive inhibition and stop a go reaction.
To measure the subject’s best performance, the computer continually resets the timing of the stop signal.
A two-day testing protocol was repeated 10 times at VUMC, 12 times at Penn, with conventional rounding on day one and acuity-based rounding on day two.
Compared to conventional rounds, after undertaking acuity-based rounds, stop signal reaction times were 39 milliseconds quicker in VUMC subjects and 16 milliseconds quicker in subjects at Penn.
“These sub-second changes may sound small, but they’re significant in the neuroscience domain. In the stop signal task, a difference of 15 to 40 milliseconds is considered appreciable,” Miles said.
“It stands to reason that the more we can do to preserve the cognitive reserves of clinicians, the better the care and greater the safety will be for patients.”
Joining the study at Penn was Meghan Lane-Fall, MD, MSHP, assistant professor of Anesthesiology and Critical Care at the Perelman School of Medicine.
Other VUMC researchers on the study include Dorothee Mueller, MD, Daniel Gay-Betton, Yaping Shi, MS, and Matthew Shotwell, PhD. The study was supported in part by the National Institutes of Health (DC005361).
