The American Journal of Medicine
Volume 117, Issue 3 , Pages 175-181, 1 August 2004

Waiting for urgent procedures on the weekend among emergently hospitalized patients

  • Chaim M Bell, MD, PhD

      Affiliations

    • Department of Medicine (CMB, DAR), University of Toronto, Toronto, Canada
    • St. Michael's Hospital (CMB), Toronto, Canada
    • Institute for Clinical Evaluative Sciences (DAR, CMB), Toronto, Canada
    • Corresponding Author InformationRequests for reprints should be addressed to Chaim M. Bell, MD, PhD, St. Michael's Hospital, 30 Bond Street, Toronto, Ontario, Canada M5B 1W8
  • ,
  • Donald A Redelmeier, MD, MSc

      Affiliations

    • Department of Medicine (CMB, DAR), University of Toronto, Toronto, Canada
    • Department of Medicine and Clinical Epidemiology Unit of Sunnybrook and Women's College Health Sciences Centre (DAR), Toronto, Canada
    • Institute for Clinical Evaluative Sciences (DAR, CMB), Toronto, Canada

Received 23 June 2003; received in revised form 2 February 2004; accepted 2 February 2004.

Article Outline

Abstract 

Purpose

Many hospital departments tend to have lower staffing levels on weekends. We evaluated the use of selected urgent procedures for emergently hospitalized patients and measured the time until procedure based upon the day of hospital admission.

Methods

We analyzed all acute care admissions from all 190 emergency departments in Ontario, Canada, between 1988 and 1997. We selected patients (n = 126,754) who underwent one of six prespecified procedures as their most responsible procedure: fiberoptic bronchoscopy, esophageal gastroduodenoscopy, magnetic resonance imaging, echocardiography, ventilation-perfusion scanning, or coronary angiography. We noted each patient's day of procedure and day of hospital admission. For waits of less than 8 days, we analyzed the time to procedure based upon the day of admission.

Results

Only 5% (n = 5903) of the urgent procedures were performed on the weekend. Of the six selected procedures, coronary angiography showed the most skewed pattern of performance (1.5% performed on the weekend) and esophageal gastroduodenoscopy showed the least skewed pattern (8% performed on the weekend). Patients admitted on Fridays or Saturdays had the longest waits for procedures. For all six procedures, patients with relatively longer waits had relatively longer total in-hospital stays (P <0.001 for each).

Conclusion

Relatively few urgent procedures are performed in emergently hospitalized patients on the weekend, suggesting that greater attention to weekend care might result in more timely interventions and shorter lengths of stay.

 

Weekends in hospitals are typified by staffing decreases in several technical departments (1). This practice pattern is often adopted when most activity reflects outpatient demand (1). However, newly admitted or other inpatients may urgently need a life-saving diagnostic evaluation on the weekend. Moreover, many services require highly technical skills that only specialists can provide. Although some requests are accommodated, prompt attention during weekends may sometimes be limited if staff are off site or budgets disallow overtime remuneration.

Minimizing prolonged hospital stays is targeted as one way to lower hospital costs 2, 3, 4, 5, 6, 7, 8. Delays in the performance of necessary procedures may compromise quality of medical care or add to hospitalization cost, or affect the care of other patients 5, 9, 10, 11, 12, 13, 14, 15. Further, delays in certain processes of care may partly contribute to increased mortality for some patients admitted to hospital on weekends compared with on weekdays 16, 17.

We sought to determine how often selected urgent procedures for hospitalized patients are performed on weekends. We also measured the time until provision of procedure based upon the day of hospital admission. Our main hypothesis was that hospital services become less available on the weekend. If so, then increases in availability might lead to faster patient care within the limits of currently idle equipment.

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Methods 

Procedure selection 

We selected six procedures that reflect diverse technologies regularly employed in acute care hospitals: fiberoptic bronchoscopy, esophageal gastroduodenoscopy, magnetic resonance imaging, echocardiography, ventilation-perfusion scanning, and coronary angiography 18, 19. Performance of these procedures involves some degree of specialized skill and, from our clinical experience, can be associated with substantial in-hospital waits.

Patient selection 

We identified consecutive patients admitted to all 190 acute care hospitals in Ontario, Canada, through an emergency department from April 1, 1988, to March 31, 1997 (16). We selected all patients who underwent one of the six prespecified procedures as their most responsible procedure during hospitalization (coding reliability: 77% to 99%) and documented the procedure's day of performance (coding reliability: 82% to 93%) 20, 21, 22. The term “most responsible” refers to procedures considered by trained data abstractors to be most important during the hospital stay and connected to the most responsible diagnosis for hospitalization. If the same procedure was performed multiple times in the same admission, only the initial event was counted. Transferred patients (<1%) were counted by the day of presentation to the initial hospital. We also documented whether the patient was discharged alive from hospital and the length of hospital stay (coding reliability: >99%) 20, 21, 22. The study was approved by the ethics committee of the Sunnybrook and Women's College Health Sciences Centre and was conducted using protocols of the Institute for Clinical Evaluative Sciences in Ontario for safeguarding confidentiality.

Weekend and weekday arrivals 

Patients were identified according to the day that they were admitted to hospital. The weekend was defined as between 0000 hours on Saturday and 2400 hours on Sunday; all other times were defined as weekdays. These times were selected because of our confidence in the reliability of the code for day of the week. This convention has been used in other studies involving administrative databases 16, 23. We classified each patient's day of admission as either a weekend or a weekday (coding reliability: 97%) 20, 21.

Statistical analysis 

The time to procedure was calculated by comparing the date of admission with the day of the procedure. Patients with procedural waits of longer than 7 days were excluded from the time-to-procedure analysis because of the possibility of an in-hospital complication or diagnoses different from presentation to hospital. All patients were included in all other analyses. Comparisons were two-tailed and employed t tests, the Wilcoxon rank sum test, or chi-squared tests, as appropriate.

We also conducted three individual comparisons of procedural waits by day of hospital admission to look for further distinctions regarding contiguous days: whether Saturday admissions had longer waits than Sunday admissions; whether Monday admissions had longer waits than Tuesday admissions; and whether Friday admissions had longer waits than Thursday admissions. We also performed an analysis of variance with a correction for multiple comparisons to assess whether hospital lengths of stay differed by individual day of admission.

We compared procedure waits above and below the median values for each of the six procedures and evaluated them with respect to in-hospital mortality and length of hospital stay. Analyses were performed with SAS Statistical Software (SAS Institute, Inc., Cary, North Carolina). Statistical significance was set at P <0.01.

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Results 

Overall, 3,789,917 emergency patients were admitted to the hospital, of whom 126,754 had one of the six selected procedures as their most responsible procedure during the hospital stay, reflecting about 1 patient for every 30 admissions (Table 1). Esophageal gastroduodenoscopy was the most common procedure performed (n = 45,167) and fiberoptic bronchoscopy was the least common procedure (n = 3973) (Table 2).

Table 1. Characteristics of Patients with Selected Procedures Admitted on Weekdays or Weekends
CharacteristicWeekday Admission (n = 95,157)Weekend Admission (n = 31,607)
Number (%)
Age group (years)
0–191632 (1.7)583 (1.8)
20–3910,037 (10.6)3240 (10.3)
40–5925,370 (26.7)8196 (25.9)
60–7944,726 (47.0)14,955 (47.3)
≥8013,382 (14.1)4633 (14.7)
Female sex42,348 (44.5)14,018 (44.4)
Arrival by ambulance30,919 (32.5)11,165 (35.3)
Academic teaching hospital*27,801 (29.2)9082 (28.7)
Charlson comorbidity score
057,180 (60.1)18,706 (59.2)
122,902 (24.1)7695 (24.3)
28283 (8.7)2900 (9.2)
≥36782 (7.1)2306 (7.3)
Surgery conducted1857 (2.0)566 (1.8)

* As classified by the Ontario Council of Teaching Hospitals.

Table 2. Comparisons of Selected Procedures for Emergently Hospitalized Patients
ProcedureProcedures Performed on WeekendP Value*
Percentage (No. on Weekend/Total No. of Procedures)
Fiberoptic bronchoscopy6.2 (245/3973)<0.001
Esophageal gastroduodenoscopy8.0 (3602/45,167)<0.001
Magnetic resonance imaging6.9 (298/4325)<0.001
Echocardiography2.4 (993/40,965)<0.001
Ventilation-perfusion scanning4.1 (432/10,639)<0.001
Coronary angiography1.5 (333/21,685)<0.001

* Comparing weekdays with weekends observed to simple split of 71% versus 29%.

An equal spread of procedure performance during the week would predict a 2/7 (29%) to 5/7 (71%) split for weekend compared with weekday procedure day. We found that of the six core procedures, 5903 (5%) were performed on weekends and 120,851 (95%) were performed on weekdays. Coronary angiography was the procedure with the most skewed utilization pattern (1.5% of procedures performed on weekends), whereas esophageal gastroduodenoscopy had the least skewed pattern (8% of procedures performed on weekends).

Time to most responsible procedure 

This analysis excluded 17,774 patients (14%) with waits longer than 7 days, leaving 108,980 patients. Overall, 16% of patients (n = 17,815) had the procedure performed on the day of hospital admission, 58% (n = 63,587) had the procedure performed between 1 and 3 days of hospital admission, and 25% (n = 27,578) had the procedure performed between 4 and 7 days of admission. The mean (± SD) time to procedure was 2.3 ± 1.9 days, and the median time to procedure was 2.0 days (interquartile range, 1 to 3 days). Ventilation-perfusion scanning had the shortest mean time to procedure (1.5 days), and coronary angiography had the longest mean time to procedure completion (3.8 days) (Table 3). Analysis of median waiting times yielded similar findings (1 day for ventilation-perfusion scanning and 4 days for coronary angiography).

Table 3. Average Waits for Selected Procedures, by Day of Hospital Admission*
ProcedureDays from Admission to ProcedureP Value
Weekday AdmissionWeekend Admission
Mean ± SD or Median (Interquartile Range)
Fiberoptic bronchoscopy3.0 ± 2.2, 3.0 (1–5)3.0 ± 2.33.0 ± 1.8>0.20
Esophageal gastroduodenoscopy1.9 ± 1.9, 1.0 (0–2)1.9 ± 1.92.1 ± 1.6<0.001
Magnetic resonance imaging2.2 ± 1.9, 2.0 (1–3)2.2 ± 2.02.3 ± 1.6>0.20
Echocardiography2.3 ± 1.8, 2.0 (1–3)2.3 ± 1.92.5 ± 1.3<0.001
Ventilation-perfusion scanning1.5 ± 1.6, 1.0 (0–2)1.4 ± 1.71.9 ± 1.2<0.001
Coronary angiography3.8 ± 2.1, 4.0 (2–6)3.9 ± 2.23.6 ± 1.5<0.001

Weekday versus weekend admission.

* Only waits of less than 8 days are included in the analysis.

The mean time to procedure was longer for patients admitted on weekends compared with on weekdays (2.4 vs. 2.3 days, P <0.001). Comparisons based on nonparametric tests of median waits yielded slightly more extreme results. Of the six procedures, magnetic resonance imaging and fiberoptic bronchoscopy did not show a statistically significant difference in wait time for patients admitted on weekends compared with on weekdays (Table 3). Esophageal gastroduodenoscopy, echocardiography, and ventilation-perfusion scanning showed statistically significant longer waits for those admitted on a weekend. However, patients undergoing coronary angiography who were admitted on the weekend had shorter procedure waits. The largest absolute difference in mean wait time was for ventilation-perfusion scanning (0.5 days, P <0.01) and the shortest wait was for fiberoptic bronchoscopy (0 days, P >0.2).

Analysis by specific day 

Patients admitted on a Friday or Saturday appeared to have the longest waits, whereas those admitted on a Monday or Tuesday appeared to have the shortest waits, with Monday associated with the shortest wait for almost all procedures (Table 4). This pattern was reflected for all six procedures. Less than half of the patients admitted on Fridays or Saturdays had their procedure performed within 2 days of admission compared with the 60% to 77% of patients admitted on the other 5 days.

Table 4. Mean Wait in Days for Selected Procedures, by Day of Hospital Admission*
ProcedureSundayMondayTuesdayWednesdayThursdayFridaySaturday
Mean ± SD
Fiberoptic bronchoscopy2.6 ± 1.72.4 ± 1.92.7 ± 2.22.9 ± 2.43.4 ± 2.53.6 ± 2.33.5 ± 1.8
Esophageal gastroduodenoscopy1.9 ± 1.41.7 ± 1.51.8 ± 1.81.8 ± 1.91.9 ± 2.12.4 ± 2.22.4 ± 1.7
Magnetic resonance imaging2.0 ± 1.52.0 ± 1.72.0 ± 1.92.1 ± 2.12.2 ± 2.22.9 ± 2.12.6 ± 1.6
Echocardiography2.1 ± 1.31.9 ± 1.51.9 ± 1.72.1 ± 2.02.5 ± 2.23.3 ± 1.82.9 ± 1.3
Ventilation-perfusion scanning1.5 ± 1.01.2 ± 1.31.2 ± 1.51.3 ± 1.61.3 ± 1.82.0 ± 2.02.3 ± 1.3
Coronary angiography3.1 ± 1.43.1 ± 2.03.6 ± 2.33.8 ± 2.44.3 ± 2.34.6 ± 1.94.0 ± 1.5
Overall wait2.1 ± 1.41.9 ± 1.62.0 ± 1.92.1 ± 2.12.5 ± 2.33.0 ± 2.22.8 ± 1.6
Percentage (No. of Procedures in 2 Days/Total No. of Procedures)
Procedure performed within 2 days of admission67 (9311/13,975)72 (12,955/18,025)73 (12,398/16,987)77 (12,132/15,869)60 (9667/16,066)32 (4838/15,112)48 (6208/12,946)

* Only waits of less than 8 days are included in the analysis.

For the comparisons of procedural waits by individual day of admission, we found that patients admitted on Saturdays had longer procedure waits than did those admitted on Sundays (2.8 vs. 2.1 days, P <0.001). Patients admitted on Fridays had longer waits than did those admitted on Thursdays (3.0 vs. 2.5 days, P <0.001). There was a statistically significant difference in mean procedure waits between patients admitted on Mondays as compared with on Tuesdays (1.9 vs. 2.0 days, P <0.001).

Patients admitted on Fridays had a longer mean length of stay than all other days of the week (P <0.05 for all). Also, patients admitted on Mondays had shorter hospital lengths of stay than patients admitted on Saturdays or Thursdays (P <0.05 for both).

Patient outcomes 

Comparisons of procedure waits above and below the median values for each of the six procedures showed that all six procedures were associated with significantly longer hospital lengths of stay when the procedure wait was greater than the median (Table 5). A statistically significant increase in hospital mortality was only noted for ventilation-perfusion scanning, where waits above the median were associated with about a 50% relative increase. Coronary angiography, echocardiography, and esophageal gastroduodenoscopy were associated with significant lower mortality for waits greater than the median (Table 5), perhaps suggesting that some especially sick patients received accelerated timeliness of care for these three procedures (Table 5).

Table 5. Effect of Procedure Wait on Length of Stay
ProcedureHospital Length of Stay (Days)In-Hospital Mortality
Procedure Wait above MedianProcedure Wait below MedianP ValueProcedure Wait above MedianProcedure Wait below MedianP Value
Mean ± SDPercentage of Admissions
Fiberoptic bronchoscopy15.2 ± 14.710.1 ± 11.9<0.00112.613.3>0.2
Esophageal gastroduodenoscopy7.8 ± 8.15.7 ± 12.3<0.0013.44.7<0.001
Magnetic resonance imaging12.3 ± 16.18.8 ± 15.5<0.0013.13.2>0.2
Echocardiography10.3 ± 16.67.5 ± 12.5<0.0014.34.80.02
Ventilation-perfusion scanning7.9 ± 9.66.0 ± 11.5<0.0013.62.1<0.001
Coronary angiography9.8 ± 6.46.5 ± 10.8<0.0011.22.2<0.001

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Discussion 

We examined six procedures often needed for emergently hospitalized patients and found that the overwhelming majority of these procedures were performed on weekdays. The day a patient was admitted to hospital affected the wait until procedure performance, but the differences between weekend and weekday waits were not large on average. The longest waits were not limited to patients admitted on the weekend. In fact, Friday admission was associated with the longest procedural waits.

While the skewed provision of weekend procedures has been identified, few reports have highlighted the effect that weekends have on length of in-hospital stay 1, 2, 3, 7, 15. Instead, delays have mostly been examined from the perspective of outpatients awaiting surgery 6, 24, 25, 26, 27. Our findings of increased lengths of hospital stay for patients with longer procedure waits suggest opportunities for cost savings and more efficient care. Reducing any delays that contribute to prolonged lengths of stay might allow hospitals to realize some savings in operating costs 7, 11, 28. For example, the East Jefferson General Hospital in Louisiana focused on weekend care for cardiology patients and achieved a 45% decrease in avoidable in-hospital days (2). However, the potential cost savings from shorter waits for procedures could be negated if staffing strategies were inefficient or wasteful.

We also observed differences in wait times for days close to the weekend. The specific nature of Friday admissions having longer waits may result from procedure deferrals until Monday. This practice may also affect patients admitted on Thursday, although to a lesser extent (15). Sunday admissions may have a shorter wait because any requests for procedures are accommodated on the Monday following a weekend (29). Thus, weekend practice fluctuations can spill over to other days of the week.

Minimization of procedure delays can affect the quality of clinical care. For example, radiology and nuclear medicine investigations performed after hours can provide fast results that alter clinical decisions 30, 31, 32, 33, 34, 35, 36, 37, 38. In one study, results from weekend ventilation-perfusion scanning changed anticoagulation decisions in more than 20% of cases and allowed for earlier discharge in about 20% of patients (30). Teleradiology services employed after hours and on weekends have helped radiologists to detect important errors in interpretations of radiographs by junior residents (36). However, our findings on mortality suggest that clinicians may also dislike delays and may triage patients carefully for accelerated care.

We found that magnetic resonance imaging and bronchoscopy performance were not associated with statistically significant differences in waits between patients admitted on weekends and weekdays. One explanation is that the generally longer mean waits are substantial regardless of the day of arrival. Alternatively, the nonstatistically significant differences comparing weekend and weekday waits for these procedures might reflect the extremely specialized nature of their referral patterns, the existence of a specific intrinsic triage mechanism, or the long prevailing baseline waits.

Improving weekend service requires motivating existing personnel in the face of limited staffing 39, 40, 41. Although human resource shortages in health care are a concern, creative scheduling solutions in some medical settings have enjoyed success, despite union opposition 2, 42, 43, 44, 45. Focused policies, such as weekend provisions for patients with presumed cardiac chest pain, have been shown to maintain safety and lower costs (28). Further, any additional weekend procedural staffing may be offered to both outpatients and inpatients to capitalize on economies of scale and reduce outpatient queues 34, 46, 47, 48. Of course, specific policies should be left to the discretion of the individual institutions as their priorities vary.

This study has several limitations. As with all studies using administrative databases, there may be coding errors that underestimate the magnitude of the observed weekend-weekday differences. We did not account for statutory holidays, but this would only have diluted the observed comparisons. Although we calculated waits from the day of hospital admission, we had no data on when the individual procedures were ordered or if the initial wait was due to a “gatekeeper” for the procedure. Additionally, we made no attempt to establish the adequacy of the procedural wait, as we focused only on comparisons between patients admitted on weekends and weekdays (26).

Further, we did not include all procedures that the cohort underwent, only the one procedure that was considered most important to the diagnosis. In the United States, International Classification for Diseases, Ninth Revision, diagnostic codes are assigned according to the primary reason for hospital admission, whereas in Canada they are assigned according to the primary reason for the entire length of hospital stay. In both countries, hospital reimbursement is at least partially related to these codes. This system has not changed much in Ontario in comparisons of past and present years.

In short, procedural waits relating to the weekend appear consistent and robust but sometimes small in magnitude. Waits for information impair rational decision making, delay important clinical management, and may affect therapeutic outcomes 9, 30, 32, 49. As such, they may contribute to the inherent differences in process of care between weekends and weekdays 16, 17. Moreover, they may form barriers to a culture of safety in hospitals 50, 51. Interventions addressing this issue may have important effects on the delivery of high-quality and timely medical care.

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Acknowledgements 

We thank Alex Kopp for help with computer programming. We are also grateful to Drs. Ross Baker, Allan Detsky, Ed Etchells, Claudio Martin, Art Slutsky, and Jack Tu for comments on drafts of this manuscript.

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 Dr. Bell is funded by a Clinician-Scientist Award from the Canadian Institutes of Health Research. Dr. Redelmeier is funded by a Career Scientist Award from the Ontario Ministry of Health and the deSouza Chair in Clinical Trauma Research of the University of Toronto.

PII: S0002-9343(04)00300-6

doi:10.1016/j.amjmed.2004.02.047

The American Journal of Medicine
Volume 117, Issue 3 , Pages 175-181, 1 August 2004