Patients who were admitted for emergency surgery on a weekend to treat left-sided diverticulitis experience more short-term complications and are markedly more likely to undergo a Hartmann procedure than are those admitted on weekdays, according to results from a large population-based study.
Longer hospital stays, significantly higher treatment costs, and higher rates of reoperations were also associated with weekend admission. However, no differences in mortality were observed between the patient groups.
Previous studies have shown worse outcomes for patients with gastrointestinal hemorrhage, kidney injury, myocardial infarction, pulmonary embolism, and intracerebral hemorrhage when they were admitted on weekends. Although the current study, led by Dr. Mathias Worni of Duke University Medical Center in Durham, N.C., and Bern (Switzerland) University Hospital, was not designed to isolate the cause of the "weekend effect" for left-sided diverticulitis patients, the authors noted that hospital staffing tends to be reduced on weekends – especially among specialists such as colorectal surgeons.
Dr. Worni and his colleagues looked at records from the Nationwide Inpatient Sample between January 2002 and December 2008. Of the 31,832 patients who were treated surgically for left-sided diverticulitis, 7,066 (22.2%) were admitted on weekends and 24,766 (77.8%) on weekdays. Patients’ mean age was 60.8 years, and more than half were women.
Among patients who were admitted on a Saturday or Sunday, a Hartmann procedure was performed on 64.8% (n = 4,580), compared with only 53.9% (n = 13,351) for those admitted on a weekday (Arch. Surg. 2012;147:649-55). The Hartmann procedure – which involves formation of a colostomy – has long been the standard surgery for people presenting with left-sided diverticulitis, but is associated with long-term complications and a low rate of reversals.
Primary anastomosis, in which colostomy is avoided, is increasingly preferred, but only 35.2% of patients who were admitted on weekends underwent primary anastomosis, compared with 46.1% of patients admitted on weekdays.
The investigators found that patients admitted on weekends had significantly higher risk for any postoperative complication (odds ratio, 1.10; P = .005), compared with patients admitted on weekdays. Risk of reoperation was also higher among weekend admissions (OR, 1.50; P less than .001).
Furthermore, median total hospital charges were $3,734 higher among patients treated on weekends, and the median length of hospital stay was 0.5 days longer (P less than .001). The authors observed that these findings should motivate improvements in the quality of weekend care.
"Physicians working on weekends are thought to be less experienced than teams working during the week," they wrote. Experienced and specialized colorectal surgeons have been shown to perform more primary anastomoses, compared with trainees or general surgeons (Arch. Surg. 2010;145:79-86; Dis. Colon Rectum 2003;46:1461-8).
Limitations of the study include the fact that it did not capture long-term outcomes or severity of disease at presentation. The latter could be of potential importance: "Some patients, especially those with milder symptoms, may prefer weekend or weekday admission and may time their admission accordingly," the investigators noted.
In an invited critique that accompanied the article, Dr. Juerg Metzger, a surgeon at Lucerne (Switzerland) Cantonal Hospital, wrote that a disparity in experience among weekday and weekend surgical staff likely accounted for the higher rate of Hartmann procedures and complications following weekend admissions.
"Work-hour restrictions do not seem to have a negative influence on mortality and morbidity in surgical patients," Dr. Metzger wrote. "However, reduced experience owing to restricted working hours may negatively influence the practical skills of younger surgeons, resulting in more limited surgery [for example, a Hartmann procedure being performed instead of a primary anastomosis] and an increase in complications related to that surgery."
In the end, Dr. Metzger wrote, "quality is expensive, and our society has to decide if it is desirable and necessary to have the best surgical quality available all the time, especially when considering that health care costs will dramatically increase. It would be relevant to analyze additional large databases, asking similar questions about the outcomes of other common diseases [for example, appendicitis, cholecystitis, and strangulated hernias] and studying the effect of weekend admission on these illnesses."
Dr. Worni’s and colleagues’ was funded by a grant from the Swiss National Science Foundation. None of the investigators declared conflicts of interest. Dr. Metzger declared that he had no conflicts of interest related to his critique.