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What’s New in the Patient Safety World

September 2020

Care Processes and the Weekend Effect



We’ve done multiple columns on “the weekend effect” and “the after-hours effect”, in which patient outcomes tend to be worse than for those during “normal” daytime hours (see list of columns below).


But there has been surprisingly little actual documentation of which specific care processes are deficient on those weekends. Liu and colleagues (Liu 2020) recently analyzed data from the American College of Surgeons’ NSQIP database on over 27,000 patients in 362 hospitals with ERAS (Enhanced Recovery After Surgery) programs for elective colorectal surgery (see our February 11, 2020 Patient Safety Tip of the Week “ERAS Rocks!”), The researchers assessed adherence to 9 postoperative process measures, comparing between patients undergoing surgery on Monday through Wednesday compared with Friday while risk-adjusting for procedure type and surgical complexity.


Those who underwent surgery on Friday, compared with Monday through Wednesday, had decreased adherence to mobilization on postoperative day one (POD#1), mobilization on POD#2, and Foley catheter removal by POD#1.


Several hospital-level factors were associated with lower weekend adherence rates: having more hospital beds, fewer nurses per bed, and fewer part-time unit staff per bed. Nonteaching hospitals were associated with lower weekend adherence rates but had better adherence rates overall compared with teaching hospitals. Hospitals with fewer nurses per bed led to a decreased probability of Foley catheter removal and mobilization on POD#1 on the weekend. (Note that having fewer nurses was also associated with decreased adherence to mobilization on POD#1 even during the weekday when compared with better-staffed hospitals).


The authors conclude that to achieve optimal outcomes, protocol adherence is important and requires appropriately resourced patient care teams. They note that the reduced adherence to mobilization and Foley catheter removal noted during the weekend was associated with certain organizational and unit-based factors including nurse and unit staffing ratios. These are potential targets to improve surgical quality to achieve desirable patient care.


We summarized many of our own thoughts on the “weekend effect” in our June 2016 What's New in the Patient Safety World column “Weekend Effect Challenged”. Our own opinion is that the “weekend effect” and “after-hours effect” are real phenomena and that the causes are multifactorial, including both patient-based and system-based contributing factors. Yes, patients admitted at these times are likely sicker and have a higher severity of illness and therefore are likely to have a higher mortality rate. However, as we’ve pointed out over and over, hospitals do not provide the same levels of service 24 hours a day, seven days a week. Staffing patterns, in terms of volume and even more so in terms of experience, are the most obvious difference but there are many others as well. Many diagnostic tests are not as readily available during these times. On-site physician 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. But the most significant difference is 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”). That is why we think that simply addressing nurse:patient staffing ratios without addressing nurse workload issues may be short-sighted.


All you have to do is spend some time in your hospital on weekends and you’ll readily see that things are different on weekends.



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

·       October 4, 2016        More on After-Hours Surgery

·       July 25, 2017             Can We Influence the “Weekend Effect”?

·       August 15, 2017        Delayed Emergency Surgery and Mortality Risk






Liu JY, Merkow RP, Cohen ME, et al. Association of Weekend Effect With Recovery After Surgery. JAMA Surg 2020; Published online August 26, 2020




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