In July 2011, the Accreditation Council for Graduate Medical Education (ACGME) reduced the consecutive number of hours that post-graduate year-1 residents can work in a single shift, from 30 to 16.1 This rule was intended to improve patient safety by reducing residents’ fatigue. Many worry that the new duty hour policy increases patient care handovers, which may cause patient harm. The net effect of the 16-hour duty limits on patient outcomes is uncertain.
Methods
In April 2011, the Vanderbilt Internal Medicine Residency Program redesigned its rotations to reduce the maximum continuous on-duty period to 16 hours. We retrospectively examined the efficiency and quality of care for non-intensive care unit (ICU) medical inpatients under the 30-hour (July-December 2010) and 16-hour (July-December 2011) duty limits at Vanderbilt University Hospital. Patient cohorts were constructed from 8 Internal Medicine resident services, with non-resident hospitalist concurrent control groups. Measures included continuity (weekly handovers); efficiency (length of stay [LOS], time of discharge); and quality and safety (Agency for Healthcare Research and Quality patient safety indicators [PSI],2 University HealthSystem Consortium complications,3 observed to expected [O:E] in-hospital mortality, all-cause 30-day readmissions to the same facility, in-hospital rapid response and code events, and ICU transfers).
Results
Rotation changes increased the number of weekly handovers from 56 to 126. The 30-hour cohort (N=2025 patients) and 16-hour cohort (N=1966 patients) did not differ significantly in hospital LOS, although mean time of discharge was 25 minutes later in the 16-hour cohort (Table). No statistically significant differences were seen in PSIs, O:E mortality, 30-day readmissions, rapid response team events, codes, or ICU transfers. UHC complications declined in the 16-hour resident cohort, with a similar trend observed among non-resident hospitalist services.
Table 1.
Table Patient Care Outcomes on Resident Services with 30- and 16-Hour Duty Limits
| Outcome | 30-Hour (n=2025) | 16-Hour (n=1966) | Difference between means (95% CI) |
|---|---|---|---|
| EFFICIENCY | |||
| Length of stay, median (IQR, 25%, 75%) | 3.04 (1.95, 5.64) | 3.11 (1.91, 5.67) | −0.075 (−0.417, 0.267) |
| Observed: Expected length of stay | 0.82 | 0.82 | 0.007 (−0.003, 0.017) |
| Time of discharge, median (IQR, 25%, 75%) | 14:47 (12:58, 16:38) | 15:15 (13:28, 17:08) | 0:25 (0:14, 0:35) |
| All cause 30-day readmission,+ n (%) | 18.57% | 17.80% | −0.77% (−3.20%, 1.60%) |
| All cause 30-day readmission+ for pneumonia patients, n (%) | 7.69% | 0.00% | −7.69% (−18.70%, 3.30%) |
| AHRQ Patient Safety Indicators/1000 patients | 3.46 | 1.02 | −2.44 (−5.86, 0.98) |
| UHC complications/1000 patients | 26.67 | 15.77 | −10.90 (−20.30, −1.48) |
| UHC Observed: Expected mortality | 0.41 | 0.55 | 0.14 (−0.01, 0.38) |
| Rapid response team events/1000 patients | 16.30 | 18.31 | 2.02 (−6.59, 10.61) |
| Code events/1000 patients | 0.99 | 1.02 | 0.03 (−1.97, 2.02) |
| ICU transfers/1000 patients | 5.43 | 7.63 | 2.20 (−3.30, 7.70) |
Planned and unplanned
IQR=Interquartile Range; UHC=University HealthSystem Consortium; AHRQ=Agency for Healthcare Research and Quality
Comment
Restructuring resident rotations to accommodate the ACGME 16-hour duty limits substantially increased patient care handovers, but did not significantly affect efficiency and quality of care among medical inpatients.
Increased handovers were an unintended consequence of the 2003 duty-hour changes.4 We anticipated increases in handovers with further work-hours restriction, because patients would be admitted by night residents and transferred to new providers in the morning. Indeed, we found a striking two-fold increase in handovers. Although we expected a corresponding rise in inefficiencies, we demonstrated no significant change in hospital LOS. We did observe a delay in discharge time of almost 30 minutes, which may be relevant in an era of pressures to improve patient throughput.
Poorly executed patient handovers are associated with medical errors,5 and we therefore evaluated the effect of the 16-hour restrictions on patient safety outcomes. We found no significant change in rates of AHRQ PSIs, consistent with previous findings.6 Additional patient safety outcomes, including rapid response and code events, ICU transfers, and inpatient mortality, did not differ significantly between the study periods, though the relatively small sample size may have resulted in insufficient power to detect uncommon events. There was a statistically significant decrease in UHC complications after implementation of the 16-hour rule. However, a similar trend occurred among patients treated on the non-resident hospitalist services, which suggests a secular effect. Importantly, the increase in patient handovers with the 2011 policy change coincided with the introduction of a new structured electronic handover application and formal handover education for residents. Additionally, transfers of care to new providers may bring fresh insights, and therefore, may offer opportunities to appreciate and correct prior lapses in care.7 Both factors may have attenuated safety hazards introduced by discontinuity.
An outcome of increasing focus is hospital readmission. Residents are intimately involved in the discharge process, and discontinuity may lead to fragmented and poorly planned transitions of care. Consistent with the literature on prior duty hour changes,8 we found no significant changes in 30-day all-cause readmissions to our institution after implementation of 16-hour duty limits.
Overall, the 16-hour duty hour changes appeared to have minimal effects on measures of efficiency and quality of care. Several reasons might explain the net neutral outcomes. Although a main goal of restricting shift length was to reduce resident fatigue, thereby improving resident performance and consequently patient care, residents’ total work and sleep may not change.8 Others have hypothesized that the pressure to complete the same amount of work in less time might impair residents’ concentration, leading to errors that might offset the potential benefits of reduced fatigue. Discontinuity and communication errors might also yield negative outcomes that mask any positive effects of reduced duty hours.9 Finally, resident duty hours are one variable in a complex hospital system that contribute to patient outcomes.
The 16-hour duty limits are the latest in a progression of changes aimed at reducing resident stress and fatigue, and potentially improving the quality of patient care. Our study highlights a potential balance between harmful and beneficial effects, that in sum result in minimal overall impact when considering a wide-range of efficiency and quality outcomes.
Acknowledgments
The authors thank Daniel Stover, MD, Cecilia Theobald, MD, Jennifer Green, MD, MPH, Joshua Denny, MD, MS, Neeraja Peterson, MD, MSc, John Sergent, MD, and Nancy Brown, MD for their input about study design and review of the manuscript. We thank Shea Polancich, RN, PhD, Martha Newton and Hank Domenico from the Vanderbilt Center for Clinical Improvement for their assistance with data extraction and statistical analysis. We also thank Tracy Dozier, MD, Eitan Friedman, MD, Waleed Khalaf, MD, Jay Montgomery, MD, Matthew Semler, MD, and Ciara Shaver, MD for their work in the development and implementation of the resident night float system at VUMC. Dr. Choma had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Footnotes
Author Contributions: Study concept and design: Choma, Hathaway, Kripalani, Sponsler, Vasilevskis; Acquisition of data: Choma Analysis and interpretation of data: Choma, Hathaway, Kripalani, Sponsler, Vasilevskis; Drafting of the manuscript: Choma, Hathaway, Kripalani, Sponsler, Vasilevskis Critical revision of the manuscript for important intellectual content: Choma, Kripalani, Vasilevskis; Statistical analysis: Choma, Hathaway, Vasilevskis; Administrative, technical, and material support: Choma; Study supervision: Choma and Kripalani
Prior presentation: Choma NN, Vasilevskis EE, Sponsler KC, Hathaway J, Stover DG, Theobald CN, Green JK, Denny J, Polancich S, Peterson NB, Kripalani S. Duty hours 2.0: Effect of the ACGME 16-hour rule on quality and efficiency of care. Society of General Internal Medicine annual meeting, Orlando, Florida, May 12, 2012.
Financial Disclosure: No relevant conflicts of interest to report.
References
- 1.Accreditation Council for Graduate Medical Education. [Accessed November 20, 2011];Resident Duty Hours in the Learning and Working Environment: Comparison of 2003 and 2011 Standards. 2010 at http://www.acgme.org/acwebsite/dutyhours/dh-ComparisonTable2003v2011.pdf.
- 2. [Accessed July 2, 2012]; http://www.qualityindicators.ahrq.gov/modules/psi_overview.aspx.
- 3.University HealthSystem Consortium. Clinical DataBase/Resource Manager Risk Adjustment Methodology. http://www.uhc.edu.
- 4.Antiel RM, Thompson SM, Hafferty FW, et al. Duty hour recommendations and implications for meeting the ACGME core competencies: views of residency directors. Mayo Clin Proc. 2011;86(3):181–91. doi: 10.4065/mcp.2010.0635. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Arora VM, Manjarrez E, Dressler DD, Basaviah P, Halasyamani L, Kripalani S. Hospitalist handoffs: A systematic review and task force recommendations. J Hosp Med. 2009;4:433–440. doi: 10.1002/jhm.573. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Rosen AK, Loveland SA, Romano PS, et al. Effects of resident duty hour reform on surgical and procedural patient safety indicators among hospitalized Veterans Health Administration and Medicare patients. Med Care. 2009;47(7):723–31. doi: 10.1097/MLR.0b013e31819a588f. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Raduma-Tomas MA, Flin R, Yule S, Williams D. Doctors’ handovers in hospitals: a literature review. BMJ Qual Saf. 2011;20:128–33. doi: 10.1136/bmjqs.2009.034389. [DOI] [PubMed] [Google Scholar]
- 8.Horwitz LI, Kosiborod M, Lin Z, Krumholz HM. Changes in outcomes for internal medicine inpatients after work-hour regulations. Ann Intern Med. 2007;147:97–103. doi: 10.7326/0003-4819-147-2-200707170-00163. [DOI] [PubMed] [Google Scholar]
- 9.Biller CK, Antonacci AC, Pelletier S, et al. The 80-hour work guidelines and resident survey perceptions of quality. J Surg Res. 2006;135(2):275–81. doi: 10.1016/j.jss.2006.04.010. [DOI] [PubMed] [Google Scholar]