Abstract

Background: In 2003, the Accreditation Council for Graduate Medical Education instituted work-hour requirements for residents, and since that time, the response from the academic neurosurgical community has been varied. To meet these requirements, some neurosurgical training programs have implemented night float systems, but the scope of these changes remains undefined.

Methods: We conducted a nationwide survey of neurosurgical residency training programs to evaluate the on-call structure and responsibilities of neurosurgery residents to elucidate a better understanding of the demands faced by trainees and programs alike.

Results: Seventy-four neurosurgery residency training programs (67.28%) comprising 1,107 residents were represented in our data; 23 (31.08%) of these programs reported having a night float system. Compared to programs with a traditional call system, those with a night float system had a significantly higher number of residents (17.74 vs. 13.71; P = 0.0079) and covered a significantly greater number of hospitals on call (3.07 vs. 2.21; P = 0.0150). There was no significant difference in the presence of a night float system between programs with advanced practice provider support on call (P = 0.177), Level I trauma center coverage (P = 1.000), and pediatric hospital coverage (P = 0.507).

Conclusion: Across the country, larger neurosurgical training programs with greater hospital demands have more readily adopted night float systems. The integration of advanced practice providers to enhance resident education and ensure the continuity of care emerges as a prominent trend that programs are utilizing to adapt to a changing healthcare landscape.

Keywords: Accreditation Council for Graduate Medical Education, Duty hours, Neurosurgery, Night float, On call, Survey

INTRODUCTION

Neurosurgical resident call duties have continued to evolve to meet Accreditation Council for Graduate Medical Education (ACGME) standards. These standards are meant to improve both patient care and resident education[ 1 - 4 ] with regulations limiting the number of consecutive hours worked by resident physicians and mandating minimum rest periods between shifts [ Table 1 ].[ 2 , 5 , 6 ] These restrictions aim to address concerns, such as resident fatigue and patient safety;[ 7 ] however, they have presented challenges for neurosurgical training programs to maintain training standards and ensure continuity of care.[ 8 - 11 ] Consequently, many programs have transitioned from traditional on-call systems to night float systems.[ 1 , 12 ] These changes have been met with mixed reactions from those in training programs, yet their impact on the training experience for residents remains undeniable.[ 13 , 14 ]

Table 1:

Current ACGME Neurosurgical Duty Hour Requirements.

Providing round-the-clock in-house coverage by resident physicians while adhering to stringent work-hour requirements has particularly affected those programs with limited residency training positions relative to their coverage needs.[ 5 ] For larger residency training programs, the night float system has become more common across the country in numerous medical specialties.[ 2 ] The ACGME defines this system as “a rotation or educational experience designed either to eliminate in-house call or to assist other residents/fellows during the night. Thoseassigned to night float are assigned on-site duty during evening/night shifts, are responsible for admitting or cross-covering patients until morning, and do not have daytime assignments. Such a rotation must have an educational focus.”[ 15 ] Further, it allows an individual resident to manage the overnight care of inpatients, see new consults, perform bedside procedures, and occasionally participate in surgical cases. While several programs have described the implementation of a night float system, the prevalence of night float programs in neurosurgery remains unclear; furthermore, knowledge of the organizational architecture of on-call duties is currently lacking in the neurosurgical literature.[ 5 , 16 ]

The purpose of this study was to assess the on-call structure and responsibilities of neurosurgery residents in the United States (US) by evaluating call frequency and schedules utilizing a 24-item survey administered to all neurosurgical programs.

MATERIALS AND METHODS

Survey design and administration

The Checklist for Reporting Results of Internet E-Surveys (CHERRIES)[ 17 ] was utilized in designing and administering this survey [ Appendix 1 ]. Before commencing data collection, this study received Institutional Review Board approval to ensure ethical compliance.

Appendix 1:

Checklist for Reporting Results of Internet E-Surveys (CHERRIES)

Survey questions were developed by the neurosurgical resident authors of the study to collect demographic information and measure constructs related to overnight residency responsibilities (i.e., night float, non-resident support, trauma coverage, and pediatric coverage) of other neurosurgical residents, which guaranteed content validity of the survey instrument. The usability and technical functionality of this closed survey were also evaluated by the primary and senior authors. The resulting 24-item, single-page online survey was hosted on the web-based survey platform Google Forms (Google, Mountain View, CA) [ Figure 1 ].

Figure 1:

Survey instrument sent to residency programs.

The population under study included all neurosurgery residents in the US. The sampling frame for the study came from a list of current neurological surgery residency training programs in the US available at neurosurgerymatch.org (http://www.neurosurgerymatch.org/residencyprogram.php), which was obtained by the authors in November 2022 to define the target population. Departmental websites were checked to identify program coordinators and their contact information.

The survey was first sent in September 2022 to residency program coordinators by email, which included registration information and a link to the online instrument. Coordinators were asked to forward the information to their residents. The survey introduction explained that participation in the survey was voluntary and that continued participation in the survey counted as informed consent. The length of the survey, the purpose of the study, and other details were also communicated to the respondents in the introduction. After receiving initial responses, subsequent follow-up emails and phone calls were conducted with coordinators as needed over the next year to enhance the participation rate of residency programs and encourage their involvement. If program coordinators did not respond to the request for participation, direct outreach to residents training in each program was made by email.

Responses, including registration information, were recorded automatically by Google Forms over the next year, and questions were not varied between responders. Consistency checks for each response were performed by the primary author, as well as the calculation of view, participation, and completion rates. Due to the length of the survey, a review step or a “back button” was not introduced, and cookies, IP checks, and log file analyses were not needed. Incomplete questionnaires were discarded, including those with atypical timestamps. No statistical corrections were made to the original data, such as imputing missing values.

Variables and definitions

Demographic variables were collected for each residency program, including the location of the program and the number of residents in the program complement. Geographic region was defined as follows: New England/Mid-Atlantic (CT, MA, ME, NH, NJ, NY, PA, RI, VT), South Atlantic (DC, DE, FL, GA, MD, NC, PR, SC, VA, WV), South Central (AL, AR, KY, LA, MS, OK, TN, TX), Midwest/North Central (IA, IL, IN, KS, MI, MN, MO, ND, NE, OH, SD, WI), and Mountain/Pacific (AK, AZ, CA, CO, HI, ID, MT, NM, NV, OR, UT, WA, WY).

The presence of a night float system was defined as the coverage of admitted inpatients, as well as new consults and admissions by a dedicated resident or team of residents working only overnight. Nurse practitioner (NP) or physician assistant (PA) support was defined as the presence of advanced practice providers to assist with patient care and clinical duties. Finally, on-call trauma and pediatric coverage was defined as the coverage of patients at a Level I Trauma Center or dedicated children’s hospital in the general call pool.

Data analysis

Data were stored securely on an encrypted network and organized using Microsoft Excel (Microsoft, Seattle, WA, USA). The collected survey responses were then subjected to statistical analyses with Python (Python Software Foundation, Wilmington, DE). Descriptive statistics were employed to summarize the demographic characteristics of the participating residency programs. The following a priori statistical comparisons were performed:

Mean number of residents per program versus the presence of a night float system

Data analysis and visualization were performed using Python with statistical graphs generated using Excel, with significance indicated by P < 0.05. Tests for normality were performed using the Shapiro–Wilk test. Nonparametric tests included the Mann–Whitney U and Chi-square test to compare groups of data that did not follow the normal distribution.

RESULTS

Demographic information

Of the 110 neurosurgery residency programs contacted, 74 (67.28%) responded to participate in the survey. Table 2 presents the demographic breakdown of participating programs. The mean number of residents per program overall was 15 (standard deviation [SD], 6.1), and the mean number of hospitals covered on call was 2 (SD, 1.39). Programs most often had 21 residents (mean 16, range 4–29) and most commonly covered 2 hospitals on call (range 1–7). Taken together, these programs represented a total of 1,107 neurosurgery residents.

Table 2:

Demographic Information of Programs (N=74) by Region.

The geographical distribution of programs covered 33 states and was categorized into 5 regions. The Midwest/North Central region had the highest representation with 17 programs (22.97%), followed by the New England/Mid-Atlantic region with 16 programs (21.62%). The South-Central region comprised 15 programs (20.27%). The South Atlantic was represented by 14 programs (18.92%) and the Mountain/Pacific region by 12 programs (16.22%).

Call structure and responsibilities

Table 3 breaks down the structure and coverage responsibilities for residents on call by region. In total, 23 (31.08%) programs reported incorporating a night float system, and 38 (51.35%) reported NP or PA support on call. Night float systems were most frequently found at programs in the New England/Mid-Atlantic region (n = 7; 43.75%), where NP/PA support on call was also most common (n = 12; 75.00%). Most programs reported covering a Level I Trauma Center (n = 68; 91.89%) and a dedicated pediatric hospital (n = 45; 60.81%) on call.

Table 3:

Call Structure and Responsibilities of Programs (N=74) by Region.

Call frequency

All 74 programs (100.00%) employed in-house call during junior residency for pager coverage, and the vast majority of programs used home-based call during senior residency to fulfill a chief role (n = 73; 98.65%). On average, residents covered 10 nights (SD, 5.88) for primary call each month during their postgraduate year(PGY)-2 with fewer calls during subsequent years. Backup or chief calls peaked at an average of 10 per month (SD, 8.48) during the PGY-7 year [ Figure 2a ]. Predictably, a night float setup yielded a greater average frequency of on-call nights per month for 2^nd-year residents (n = 15) than a traditional call system (n = 8) [ Figures 2b and c ].

Figure 2:

(a) Distribution of call frequency during residency for all programs. (b) Distribution of call frequency during residency for night float programs. (c) Distribution of call frequency during residency for traditional call programs.

Comparisons

In analyzing the differences between programs that have adopted night float and those that did not, a significantly higher average number of residents was observed in programs with a night float system compared to programs without one (17.74 vs. 13.71; P = 0.0079) [ Figure 3a ]. Similarly, programs with a night float system reported a greater average number of hospitals covered on call than those with a traditional system (3.07 vs. 2.21, P = 0.0150) [ Figure 3b ].

Figure 3:

(a) Number of residents per program by the presence of a night float system. (b) Number of hospitals covered on call by the presence of a night float system.

No significant difference was observed between the presence of a night float system and categorical variables, such as NP or PA support on call (χ² (1) = 1.826; P = 0.177), Level I trauma center coverage (χ² (1) = 0.0; P = 1.000), or pediatric hospital coverage (χ² (2) = 1.360; P = 0.507). These findings suggest that while the presence of a night float system may be related to the size of the residency program and the number of hospitals covered, it is not related to the distribution of support roles or the type of coverage provided.

DISCUSSION

Past literature

The ACGME’s implementation of resident duty hour restrictions in 2003 has had a complex impact on neurosurgical resident training, patient safety outcomes, and the overall healthcare delivery system, which prompted varied responses from the neurosurgical community and highlighted the intricate balance between educational rigor, clinical experience, and patient safety.[ 18 - 20 ] While many in the field harbored concerns about the detrimental effects of duty-hour restrictions on patient and educational outcomes,[ 21 - 23 ] others have encouraged neurosurgery as a whole to “embrace these changes and look for opportunities to improve our system of residency education.”[ 24 ] The effects of these changes have been closely investigated by other specialties,[ 25 - 27 ] but some have argued that neurosurgery is unique to other fields and thus merits specific consideration and evaluation,[ 28 - 31 ] a fact that underscores the need for further research to assess the magnitude of these changes.

The effectiveness of night float systems in maintaining case volumes appears to be institution-specific, with some programs successfully preserving or even increasing operative experiences for residents at various PGY levels.[ 4 , 32 ] One institution reports that their night float schedule includes a PGY2 and PGY3 rotating monthly at closely located hospitals, working Sundays through Fridays with Saturday nights off. This totals 78 h of work with 36 h of dedicated time off each week, ultimately meeting ACGME requirements. In a program with three residents per year, this equals 4 months on night float per year. Consequently, over a year, junior residents and senior residents saw a decrease from 20 weeks to 16 weeks and 16 weeks to 2 weeks of overnight (in-house) calls/year, respectively. This did not ultimately jeopardize junior operative experience or educational opportunities. In addition, senior residents as a group saw a 24 OR-only case increase per month, on average, over 4 years after implementation, highlighting the increased night-time workload.[ 32 ] While that institution reports monthly rotations for junior residents, another neurosurgical program details PGY2 residents rotating through 2-week periods of 14-h “day-float” and “night-float” calls without operative responsibilities and 2 weeks in the operating room throughout the year.[ 33 ] While no two programs are identical in their schedules of night float systems, they typically consist of consecutive shifts of 12 h over 1 week to 2 months.[ 34 , 35 ] Although no universal night float system exists, these insights both provide a clearer picture of the working conditions and increased educational opportunities provided by a night float system.[ 32 ]

While night float systems can increase case volume and enrich educational opportunities, increased patient handoffs associated with night float rotations could potentially compromise the continuity of care, an aspect that some studies have linked to increased preventable errors and patient dissatisfaction.[ 5 , 11 , 22 , 36 , 37 ] Preserving educational and clinical standards has necessitated an increased reliance on advanced practice providers [ 24 ], so understanding how advanced practice providers can support residency training programs, especially under duty hour constraints, could inform strategies to enhance education and patient care. Moreover, resident satisfaction with night float compared to traditional call systems appears to be generally favorable, with a number of studies indicating a strong preference for night float.[ 13 , 32 ] However, this satisfaction must be balanced with clinical and educational outcomes. Indeed, this discussion points to a landscape of neurosurgical education that finds itself at a crossroads. Duty-hour restrictions and night float systems are central to this transformation. While the goal of improving resident training and patient outcomes is clear, the methods to achieve this within the field of neurosurgery remain a work in progress.

Our results

Our survey engaged 74 neurosurgery training programs comprising 1,107 residents to elucidate key findings regarding on-call configurations in the era of ACGME duty-hour restrictions. These programs spanned across 33 states and demonstrated a mean of 15 residents per program, reflecting a broad spectrum of training environments. Even though the median number of hospitals covered by residents on call was 2, this variable varied significantly from 1 to 7 hospitals, indicating substantial diversity in the scale and scope of service requirements among programs.

Crucially, a statistically significant relationship was observed between the number of hospitals covered on call and those programs that had instituted a night float system. Specifically, programs with wider hospital needs on call were more likely to implement night float systems, a finding which may point to these systems’ utility in managing complex coverage logistics across multiple facilities. Similarly, analyzing program sizes in relation to night float system adoption revealed a significant trend: residencies with night float systems had a greater average size of approximately 18 residents compared to 14 residents in programs with traditional on-call frameworks. This significant difference highlights a tendency for larger programs to implement night float systems, possibly due to their greater resources and ability to adapt to duty-hour restrictions.

While the support of NPs and PAs on call was not significantly associated with the presence of a night float system, nor was the coverage of a Level I Trauma Center or pediatric hospital, the data did shed some light on the integration of night float systems with traditional on-call duties. Approximately half of the programs reported working with NPs or PAs for additional on-call support, and a majority reported both trauma and pediatric responsibilities. Therefore, our findings suggest a trend toward multi-disciplinary teams to ensure coverage, a finding that could be particularly relevant for programs with large resident cohorts and extensive hospital demands.

Implications and future directions

The insights gleaned from this study underscore the need for a detailed understanding of how neurosurgery training programs are adapting to duty-hour restrictions. The variability in program size and geographic distribution, as well as the different models of night float systems in use, reveals a reality where “one-size-fits-all” solutions are infeasible. Our findings highlight that programs have opted for a tailored approach based on the discrete demands and resources of each program.

The use of advanced practice providers as a complement to resident staff, particularly in larger programs, is an observation that warrants further investigation. The implications of this for resident training, patient outcomes, and the overall healthcare delivery system remain to be fully understood. Moving forward, future research must adopt a more granular approach, potentially through multi-center collaborations, to provide a robust evidence base that can guide policy and practice. Such efforts should aim to evaluate the long-term outcomes of duty-hour restrictions and night float systems on resident education and patient safety.

Limitations

Several limitations should be acknowledged. First, the survey data are retrospective and subjective to a degree. Our study obtained limited data from programs, particularly in the Northeast and Midwest, despite achieving a response rate of nearly 70%. In addition, details regarding systems with multiple call pools may not fit neatly into a standardized framework, and for those cases, responders may have had limited flexibility in their responses. Finally, the desire to avoid reporting duty violations among participants could have introduced bias into some of the responses.

CONCLUSION

Our comprehensive survey of US neurosurgery residency training programs illustrates the scope of night float systems across the country. The results revealed that larger programs with broader hospital coverage have been more inclined to integrate night float systems, often supplemented by advanced practice providers, to maintain resident education and the continuity of care. While this study supports the adaptability of neurosurgical training to regulatory changes, it also highlights the need for continued investigation and research. Ultimately, ensuring the excellence of neurosurgical training and patient outcomes in the face of evolving educational frameworks remains a paramount objective for the neurosurgical community.

Ethical approval:

The research/study was approved by the Institutional Review Board at the University of Tennessee Health Science Center, number 22-08936-XM, dated August 22, 2022.

Declaration of patient consent:

Patient’s consent is not required as there are no patients in this study.

Financial support and sponsorship:

Nil.

Conflicts of interest:

There are no conflicts of interest.

Use of artificial intelligence (AI)-assisted technology for manuscript preparation:

The authors confirm that there was no use of artificial intelligence (AI)-assisted technology for assisting in the writing or editing of the manuscript and no images were manipulated using AI.

Disclaimer

The views and opinions expressed in this article are those of the authors and do not necessarily reflect the official policy or position of the Journal or its management. The information contained in this article should not be considered to be medical advice; patients should consult their own physicians for advice as to their specific medical needs.

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