Patient Safety Tip of the Week
July 25, 2017
Can We Influence the “Weekend Effect”?
In our many columns
on the “weekend effect” or the “after hours effect” we have stressed that there
is probably a combination of patient-related and system-related factors
contributing (see, for example, our What's New in the Patient Safety World
columns for November 2013 “The
Weekend Effect: Not One Simple Answer” and June 2016 “Weekend
Effect Challenged”). It’s a
complex interaction and it’s difficult to determine the relative contribution
of each of those two factors.
A new study adds an
interesting twist to that complex interaction: the method of patient arrival
may play a role! Most previous studies on the weekend effect have used
administrative data to perform risk adjustments and estimate patient severity
of illness. These may not adequately measure severity of illness. Now, Anselmi and colleagues (Anselmi 2017)
used arrival at the emergency department by ambulance as a proxy for greater
severity of illness to analyze mortality and its variation by day and time of
the week.
In their analysis, when using conventional risk-adjustment
methods, there appeared to be a higher risk of mortality following emergency
admission to hospital at nights and on weekends. However, after accounting for
mode of arrival at hospital, this pattern changed substantially, with no
increased risk of mortality following admission at night or for any period of the
weekend apart from Sunday daytime.
The authors conclude that risk-adjustment based on inpatient
administrative data probably does not adequately account for illness severity
and that the elevated mortality at weekends and at night probably reflects a higher
proportion of more severely ill patients arriving by ambulance at these times.
Another recent study (Walker
2017) used laboratory data to improve risk adjustment and severity of
illness. After adjusting for multiple confounders including demographics,
comorbidities, and admission characteristics, incorporating non-linearity and
interactions, they then considered the effect of adjusting for 15 common hematology
and biochemistry test results or proxies for hospital workload. Adjustment for
test results explained 33% of the excess mortality associated with emergency
admission on Saturdays compared with Wednesdays, 52% on Sundays, and 87% on
public holidays after adjustment for standard patient characteristics. Excess
mortality was predominantly restricted to admissions between 1100 h and 1500 h
on weekend days. They also found that no hospital workload measure was
independently associated with mortality. But the latter measures (total
admissions, total net hospital occupancy [admissions minus discharges], and
percentage of bed occupancy based on inpatient duration) did not include actual
staffing information. Those authors concluded that the weekend effect arises
from patient-level differences at admission rather than reduced hospital
staffing or services.
That said, we probably cannot do much about the
patient-related factors contributing to the “weekend effect” or “after hours
effect”. But we can certainly do more to mitigate some of the system-related
factors contributing to them.
In our February 23,
2016 Patient Safety Tip of the Week “Weekend
Effect Solutions?” we cited
a study which suggested that specific hospital resources might be used
to overcome the “weekend effect” seen in urgent general surgical procedures (Kothari
2015). Researchers identified emergent/urgent surgeries (appendectomies,
cholecystectomies, and hernia repairs) in the HCUP database for Florida from
2007 to 2011 and used as a surrogate for the weekend effect an extended median
length of stay on the weekend compared to weekdays. They identified 17 out of
166 hospitals that did not exhibit the “weekend effect” and looked to see how
these hospitals differed from the others. Patient level factors like
socioeconomic status did affect the occurrence of the weekend effect but
hospital characteristics had more important associations with the weekend
effect. They found that hospitals not
having the weekend effect were more likely to have higher nurse-to-patient
ratios, full adoption of electronic medical records, home health programs, pain
management programs, and inpatient physical rehabilitation. The authors hypothesize
that the improvement in the weekend effect at some hospitals is a result of “the
ability of the identified components of perioperative infrastructure to assist patients
with increased discharge needs, improve transitional care, and ensure care continuity
from the week to the weekend”.
The study, of course, was limited by its use of
administrative data and use of a proxy for the weekend effect. Also, the nurse
staffing ratios were averages and did not specify whether such differed on
weekends. Also questioned is why 3 procedures that typically have very low
mortalities were chosen. Also, these are associations and may not play a causal
role. But are they plausible contributory factors? They certainly could be.
Previous work shows that the weekend effect is complex and involves both
patient-related factors and quality of care factors (see our November 2013 What's
New in the Patient Safety World column “The
Weekend Effect: Not One Simple Answer”).
In a recent followup study Kothari
and colleagues (Kothari
2017) identified components of electronic health record systems that were
associated with less pronounced weekend effect in patients undergoing urgent
general surgical procedures. Weekend effect was 33% less likely in those
hospitals with electronic operating room scheduling compared with hospitals
using paper-based scheduling. In addition, weekend effect was 35% less likely
in those hospitals having electronic bed-management systems.
In our many previous columns on the weekend effect or
after-hours effect we have pointed out how hospitals differ during these more
vulnerable times. Staffing patterns (both in terms of volume and experience)
are the most obvious difference but there are many others as well. Many
diagnostic tests are not as readily available during these times. Physician and
consultant availability may be different and cross-coverage by physicians who
lack detailed knowledge about individual patients is common. You also see more
verbal orders, which of course are error-prone, at night and on weekends.
We’ve often said the use of the simple nurse:patient staffing ratio on weekends may be
misleading. That is because there is often a significant difference in nurse
workload on weekends. We’ve described the tremendous increase in nurse
responsibilities on weekends due to lack of other staff (no clerical staff,
delayed imaging, physicians not on site) that add additional responsibilities
to their jobs. Our December 15, 2009 Patient Safety Tip of the Week “The
Weekend Effect” discussed how adding non-clinical administrative tasks to
already overburdened nursing staff on weekends may be detrimental to patient
care. Just do rounds on one of your med/surg floors
or ICU’s on a weekend. You’ll see nurses answering phones all day long, causing
interruptions in some attention-critical nursing activities. Calls from
radiology and the lab that might go directly to physicians now often go first
to the nurse on the floor, who then has to try to track down the physician.
They end up filing lab and radiology reports or faxing medication orders down
to pharmacy, activities often done by clerical staff during daytime hours. Even
in those facilities that have CPOE, nurses off-hours
often end up entering those orders into the computer because the physicians are
off-site and are phoning in verbal orders. You’ll also see nurses giving
directions to the increased numbers of visitors typically seen on weekends.
They may even end up doing some housekeeping chores and delivering food trays.
All of these interruptions and distractions obviously interfere with nurses’
ability to attend to their clinically important tasks (see our Patient Safety
Tips of the Week for August 25, 2009 “Interruptions,
Distractions, Inattention…Oops!” and May 4, 2010 “More
on the Impact of Interruptions”). We thus think that simply addressing nurse:patient staffing ratios
without addressing nurse workload issues may be short-sighted.
It is clear we have not yet achieved the desired state in
which our systems of hospital care are equivalent 24 hours a day, 7 days a
week. Add to this the increase in acuity or severity for patient requiring
weekend or after-hours admission and it is not surprising that we see less desirable
outcomes in those situations.
Some of our previous
columns on the “weekend effect”:
·
February 26, 2008 “Nightmares….The
Hospital at Night”
·
December 15, 2009 “The
Weekend Effect”
·
July 20, 2010 “More
on the Weekend Effect/After-Hours Effect”
·
October 2008 “Hospital
at Night Project”
·
September 2009 “After-Hours
Surgery – Is There a Downside?”
·
December
21, 2010 “More
Bad News About Off-Hours Care”
·
June
2011 “Another
Study on Dangers of Weekend Admissions”
·
September
2011 “Add
COPD to Perilous Weekends”
·
August
2012 “More
on the Weekend Effect”
·
June
2013 “Oh
No! Not Fridays Too!”
·
November
2013 “The
Weekend Effect: Not One Simple Answer”
·
August
2014 “The
Weekend Effect in Pediatric Surgery”
·
October
2014 “What
Time of Day Do You Want Your Surgery?”
·
December
2014 “Another
Procedure to Avoid Late in the Day or on Weekends”
·
January
2015 “Emergency
Surgery Also Very Costly”
·
May 2015
“HAC’s
and the Weekend Effect”
·
August
2015 “More
Stats on the Weekend Effect”
·
September
2015 “Surgery
Previous Night Does Not Impact Attending Surgeon Next Day”
·
February
23, 2016 “Weekend
Effect Solutions?”
·
June
2016 “Weekend
Effect Challenged”
References:
Anselmi L, Meacock
R, Kristensen SR, et al. Arrival by ambulance
explains variation in mortality by time of admission: retrospective study of
admissions to hospital following emergency department attendance in England. BMJ
Qual Saf 2017; 26(8):
613-621
http://qualitysafety.bmj.com/content/26/8/613
Kothari AN, Zapf MAC, Blackwell RH, et al. Components of
Hospital Perioperative Infrastructure Can Overcome the Weekend Effect in Urgent
General Surgery Procedures. Annals of Surgery 2015; 262(4): 683-691, October
2015
Kothari AN, Brownlee SA, Blackwell RH. Association Between Elements of Electronic Health Record Systems and the
Weekend Effect in Urgent General Surgery (Research Letter). JAMA Surgery 2017;
Published online March 29, 2017
http://jamanetwork.com/journals/jamasurgery/article-abstract/2613701
Walker AS, Mason A, Quan TP, et
al. Mortality risks associated with emergency admissions during weekends and
public holidays: an analysis of electronic health records. The Lancet 2017;
published online May 9, 2017
http://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(17)30782-1.pdf
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