This is another one of those studies that shows pretty much what you
would expect. There are some surprises, though:
Nap Awakens ER Residents and Nurses
By Judith Groch, Senior Writer, MedPage Today
November 03, 2006
STANFORD, Calif., Nov. 3 -- Allowed a 40-minute nap midway through
12-hour night shifts, emergency room residents and nurses responded
with more vigilance and vigor, found researchers here.
Nevertheless, the randomized study that compared nappers
non-nappers working the night shift at a Stanford hospital ER was not
all positive. The nappers did not exceed the nonnappers in all
parameters, and during post-shift driving simulator tests even the
nappers had catastrophic lapses in motor skills.
the driving tests, simulating a commute home after work, cars left the
road or crashed into oncoming vehicles, Rebecca Smith-Coggins, M.D., of
Stanford, and colleagues, reported in the November issue of the Annals
of Emergency Medicine.
During the naps, the nappers slept, on average, for about 25 of the
alloted 40 minutes.
The study showed that the test subjects who took naps actually did
worse on a test of cognitive performance, administered immediately
after awakening. There was no difference on the Profile of
Mood States, a test that measure states such as depression and
Next, I would like to see if giving them a one-hour break, with 40
minutes allowed for sleep, and 20 minutes alloted for waking up, would
help even more.
One of the more worrisome findings pertains to driving performance.
From the original article ( href="http://www.annemergmed.com/article/PIIS0196064406002393/fulltext">Improving
Alertness and Performance in Emergency Department Physicians and
Nurses: The Use of Planned Naps)
Although there were no aggregate differences in
driving performance between NAP and NONE, there were a substantial
number of occurrences in both groups of catastrophic lapses in driving.
We classify these as dangerous driving, in which the car is leaving the
road or colliding with an oncoming vehicle. Across all subjects,
approximately 8% of the drive was spent with such events occurring;
each of these occurrences would likely result in a lethal outcome
during a real drive. Comparing dangerous driving in the same
individuals between shifts showed the driving of subjects who did not
nap worsened on night 3, whereas that of napping subjects improved
They point out that the driving simulator is not as stimulating as real
driving. The implication is that the subjects might not do as
badly while driving a real car on a real street, but the results are
Chad Orzel, at Uncertain Principles, href="http://scienceblogs.com/principles/2006/11/shorter_hours_for_doctors.php">made
note of the trend toward shorter working hours for residents,
thinking it is a good thing. I'd have to say that the results
of the driving test provide a bit of evidence to support that notion.
I just read this to my wife, who always works 12-hour night shifts.
Sounds like a good case for public transit or even a hospital shuttle or taxi chits.