The “weekend effect”
(sometimes also known as the “after hours effect” since many of the same
results apply to patients admitted at night as well as on weekends) in which
increases in mortality, complications or adverse events are seen for patients
admitted on weekends has been demonstrated for a wide range of both surgical
and medical conditions. Our numerous columns on the “weekend effect” have
stressed that there are likely both patient-related and system-related factors
underlying the phenomenon (see, for example, our November 2013 What's New in the Patient Safety World column “The
Weekend Effect: Not One Simple Answer”).
Our June 2016 What's
New in the Patient Safety World column “Weekend
Effect Challenged” noted
several recent articles have challenged the concept of the “weekend effect” and
pointed out deficiencies in case identification methodologies that may give
rise to inaccurate conclusions. But a couple new studies demonstrate both a
“weekend effect” and an “after hours” effect for surgery, though the weekend
effect may have been reduced somewhat in recent years.
A study from the UK showed that the “weekend effect” for
emergency general surgery has improved over the past 15 years (McCallum 2016).
The researchers showed that the 30-day mortality rate is indeed higher for
patients having surgery on Saturdays and Sundays, compared to weekdays. But
there was no difference in 30-day mortality by day of the week admitted. Moreover,
for those surgeries done on the weekend the 30-day mortality rates have
decreased from 5.4% in 2000-2004 to 2.9% in 2010-2014.
On the other hand, Canadian researchers showed that surgical
mortality does vary by time of day (WFSA 2016).
They evaluated all surgical procedures
for the past 5 years, including all elective and emergent surgical cases except
ophthalmic and local anesthesia cases. After adjustment for age and ASA scores,
patients operated at night (11:30 PM-7:29 AM) were 2.17 times more likely to
die within 30 days than those operating on during regular daytime working
hours (7:30 AM-3:29 PM). Those operated on in the late day (3:30 PM-11:29 PM) were
1.43 times more likely to die than those operated on during regular daytime
working hours.
Of course, it is
logical that patients operated on after-hours are likely to be sicker and thus
have a higher mortality. The Canadian authors tried to adjust for that using
age and ASA scores but those likely are imperfect adjusters. Other potential
factors contributing to the higher after-hours mortality as noted by the
authors include provider fatigue during anesthesia and surgery, overnight
hospital staffing issues, delays in treatment, or the patient being too sick to
be postponed prior to treatment.
We’ve done several prior columns pointing out some of the
downsides of after-hours surgery. In our What's New in the Patient Safety World
columns for September 2009 “After-Hours
Surgery – Is There a Downside?” and October
2014 “What
Time of Day Do You Want Your Surgery?” we discussed studies that showed for
certain types of orthopedic surgery after hours there was an increased need for
reoperations for removal of painful fracture hardware (Ricci 2009) and laparoscopic
cholecystectomies done at night
compared to daytime were associated with a higher conversion rate to open
cholecystectomy (11% vs 6%) (Wu
2014). We also noted previous
studies by Kelz and colleagues that showed increased
morbidity in non-emergent surgical cases done “after hours”, one in the VA
system (Kelz 2008)
and another in a private hospital
setting (Kelz
2009). And our January 2015 What's New in the Patient Safety World column “Emergency
Surgery Also Very Costly” suggested, in addition to the human costs of
after-hours surgery there may also be financial costs.
Why should “after hours” surgery be more prone to adverse
outcomes than regularly scheduled elective surgery? There are many reasons
aside from the fact that patients needing emergency and after hours surgery are
generally sicker. For surgery, in particular, the impact of time of day on
teamwork is important. You are often operating with a team that is likely
different from your daytime team. All members of that team (physicians, nurses,
anesthesiologists, techs, etc.) may not have the same level of expertise or
experience as your regular daytime team (because many hospitals have
“seniority” policies, you may have less experienced personnel on your OR
“on-call” teams) and the team dynamics between members is likely to be
different. The post-surgery recovery unit is likely to be staffed much
differently after-hours as well. The staff may be more likely to be unfamiliar
with things like location of equipment. And some of the other hospital support
services (eg. radiology, laboratory, sterile
processing, etc.) may have lesser staffing after-hours. Just as importantly,
many or all of the “on-call” staff that make up the after-hours surgical team
have likely worked a full daytime shift that day so fatigue enters as a
potential contributory factor. And there are always time pressures after hours
as well. In addition, one of the most compelling reasons surgery is done at
night rather than deferred to the next morning is the schedule of the surgeon
or other physician for that next morning (either in surgery or the cath lab or his/her office). Because the surgeon does not
want to disrupt that next day schedule, he/she often prefers to go ahead with
the current case at night. Similarly, many hospitals run very tight OR
schedules and adding a case from the previous night can disrupt the schedule of
many other cases.
We highly recommend hospitals take a hard look at surgical
cases done “after hours”. You need to look at the morbidity and mortality
statistics of such cases. In particular, you need to determine which cases
truly needed to be done after hours and, perhaps more importantly, which ones
could have and should have been done during “regular hours”. If the latter are
significant, you need to consider system changes such as reserving some “regular
hours” for such cases to be done the following morning. You may have to alter
the scheduling of cases for individual surgeons as well. For example, perhaps
the surgeon on-call tonight should not have elective cases scheduled tomorrow
morning. That way, if a case comes in tonight that should be done tomorrow
morning you will have both a “free” OR room and a “free” surgeon. And you would
need to develop a list of criteria to help you triage cases into “regular” or
“after-hours” time slots.
Some of our previous
columns on the “after-hours” surgery:
·
September 2009 “After-Hours
Surgery – Is There a Downside?”
·
October
2014 “What
Time of Day Do You Want Your Surgery?”
·
January
2015 “Emergency
Surgery Also Very Costly”
·
September
2015 “Surgery
Previous Night Does Not Impact Attending Surgeon Next Day”
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:
McCallum IJD, McLean RC, Dixon S, O'Loughlin P.
Retrospective analysis of 30-day mortality for emergency general surgery
admissions evaluating the weekend effect. British Journal of Surgery 2016; 12
Aug 2016
http://onlinelibrary.wiley.com/doi/10.1002/bjs.10261/full
WFSA (World Federation of Societies of Anaesthesiologists).
Five-year study reveals patients operated on at night twice as likely to die as
patients who have daytime operations. Science Daily 2016; August 29, 2016
Regarding:
Wang N, et al. Retrospective analysis of time of day of
surgery and its 30 day in-hospital postoperative mortality rate at a single
Canadian institution. Poster presentation 601. World Congress of Anaesthesiologists 2016
https://www.sciencedaily.com/releases/2016/08/160829192642.htm
Ricci WM, Gallagher B, Brandt A, Schwappach
J, Tucker M, Leighton R. Is After-Hours Orthopaedic
Surgery Associated with Adverse Outcomes? A Prospective Comparative Study. J Bone
Joint Surg Am. 2009; 91: 2067-2072
http://www.ejbjs.org/cgi/content/abstract/91/9/2067
Wu JX, Nguyen AT, de Virgilio C, et al. Can it wait until
morning? A comparison of nighttime versus daytime cholecystectomy for acute
cholecystitis. Amer J Surg
2014; published online first September 20, 2014
http://www.americanjournalofsurgery.com/article/S0002-9610%2814%2900438-3/abstract
Kelz, R.R., Freeman, K.M.,
Hosokawa, P.W. et al. Time of day is associated with postoperative morbidity:
an analysis of the national surgical quality improvement program data. Annals
of Surgery 2008; 247: 544–552
http://www.ncbi.nlm.nih.gov/pubmed/18376202?dopt=Abstract
Kelz RR, Tran TT, Hosokawa P, et
al. Time-of-day effects on surgical outcomes in the private sector: a
retrospective cohort study. J Am Coll Surg 2009; 209(4): 434-445.e2.
http://www.journalacs.org/article/S1072-7515%2809%2900507-9/abstract
Print “PDF
version”