Abstract
Background
In 2006, Cancer Care Ontario created Surgical Oncology Standards for the delivery of HPB surgery including hepatectomy and pancreaticoduodenectomy (PD). Our objective was to identify the impact of standardization on outcomes after hepatopancreatobiliary (HPB) surgery in Ontario, Canada.
Study Design
Population-level analysis of patients undergoing hepatectomy or PD (2003–2019). Logistic regression models were used to compare 30- and 90-day mortality and length of stay (LOS), before (2003–2006), during (2007–2011) and after (2012–2019) standardization. Interrupted time series (ITS) models were used to co-analyze secular trends.
Results
A total of 7,904 hepatectomies and 5,238 PDs were performed. >80% of all cases were performed at a designated center (DC) before standardization. This increased to >98% in the post-standardization era. Median volumes at DCs increased from 55 to 67 hepatectomies/year, and 22 to 50 PDs/year over time. 30-day mortality after hepatectomy was 2.6% before, and 2.3% post-standardization (p=0.9). 30-day mortality after PD was 3.6% before, and 2.4% post-standardization (p=0.1). Multivariable analyses revealed a significant difference in 90-day mortality following PD post-standardization (4.3% vs. 6.3%; aOR 0.7, p=0.03). Median LOS was shorter for hepatectomy (6 days vs. 8 days) and PD (9 days vs. 14 days; p<0.0001), after standardization. Immediate and late effects on mortality and LOS were likely attributable to secular trends, which pre-dated standardization.
Conclusion
Standardization was associated with a higher volume of hepatectomy and PDs with further concentration of care at DCs. Pre-existing quality initiatives may have attenuated the effect of standardization on quality outcomes. Our data highlight the merits of a multi-faceted provincial system for enabling consistent access to high quality HPB care throughout a region of 15-million people over a 16-year period.
Keywords: Hepatopancreatobiliary surgery, outcomes, quality, regionalization, standardization, volume
Précis
In this population-based analysis we highlight the merits of a multi-level, regulated provincial strategy to standardize complex HPB surgery in Canada’s most populous province. This approach ensured access to consistently high-quality care across a large geographical area over a 16-year period.
Introduction
The impact of surgeon and hospital case volumes on clinical outcomes has been extensively studied as a marker of quality for a variety of surgical procedures (1–4). Patients undergoing complex, high risk procedures, such as hepato-pancreato-biliary (HPB) surgery, have been shown to derive the greatest benefit from higher volume centres with respect to improvements in clinical outcomes (5–11). This includes improvements in morbidity, failure to rescue, mortality, length of stay (LOS), and overall survival (5–14) at high volume centres.
The positive volume-outcome relationship has led to policy changes in various jurisdictions towards regionalization of care – the deliberate reorganization of cancer services based on explicit processes and structures to improve the quality of care (3). In the United States, population-level inpatient mortality for complex HPB surgery has been reported at 7% versus 3% at low (<8 cases/year) and high-volume centers (≥29 cases/year), respectively (6). Annual case volumes, however, are often used as an arbitrary surrogate for “quality” nationally, where case allocation at the hospital level may not always be subject to formalization or public designation.
There remains a need to better distinguish the effect of formal standardization vis-à-vis quality metrics and benchmark outcomes of complex HPB surgery, especially within a publicly funded healthcare system and across a large geographical area. Much of these data stem from Europe, including the Netherlands and Nordic countries, where superior short-term outcomes have been achieved with central oversight of major HPB surgery. This includes short-term mortality rates ranging from 1–4%, as well as a higher proportion of patients being offered surgical resection, and a greater ability to rescue complications to prevent death (10–14). In the Canadian context, efforts to regionalize high acuity and oncologic surgery have been associated with increased centralization of surgical services, with designated centers (DCs) assuming the care of higher-risk patients (15, 16). Improvements in post-operative mortality over time; however, were consistent with pre-existing secular trends as opposed to regionalization efforts (15, 16).
Cancer Care Ontario (CCO) is the provincial agency responsible for oversight of cancer services for Canada’s most populous province, with 15 million people spread over one million km2. In 2006, the agency published the Surgical Oncology Standards pertaining to complex HPB surgery (17). This was an all-encompassing formal mandate recognizing the human, physical and fiscal capital required to achieve excellent system-level outcomes. It included a more explicit requirement in surgeon training (i.e., minimum of two fellowship trained HPB surgeons), as well as the administrative structure and required resources of a HPB service such as around-the-clock access to interventional radiology and endoscopy. Volume targets were set at least 50 major HPB cases per year, including at least 20 pancreatic resections, with in-hospital and 30-day mortality benchmarks of 5% for major pancreatic resection and 3% for anatomical liver resection (17). The policy was also linked with measurements of performance through publicly reported quality indicators and led to the designation of ten regional HPB centres across Ontario.
The objective of this study was to assess the impact of these Standards on organization of care delivery and clinical outcomes following hepatectomy and pancreaticoduodenectomy (PD) in the province of Ontario, Canada.
Methods
Data Source and Study Population
We used provincial administrative healthcare datasets, linked using unique encoded identifiers. These databases are independently validated through audits and validation studies and have been demonstrated to provide valid diagnostic, procedural, and outcome data (18–21).
We studied adult patients (≥18 years) undergoing hepatectomy or PD in Ontario between April 2003 and March 2019. Formal standardization was initiated in June 2006. Cohorts were divided a priori into three eras: pre-standardization (April 2003 to March 2007), standardization (April 2007 to March 2012), and post-standardization (April 2012 to March 2019). Exclusion criteria were age <18y, missing or cancelled main intervention, out of province records, abandoned and out of hospital, and/or an invalid patient identifier. A list of DCs was used to determine the status of hospitals performing HPB surgery (DC vs non-DC) (22).
The study was conducted and reported following the RECORD (REporting of studies Conducted using Observational Routinely-collected Data) statement (23). As per CCO quality improvement agreements, the study was not subject to institutional research ethics board approval.
Outcomes
We measured 30- and 90-day all-cause mortality from surgery date using death date attained from Ontario Cancer Registry (OCR) and Registered Persons Database (RPDB). LOS related to surgical intervention was taken directly from Canadian Institute for Health Information Discharge Abstract Database (CIHI-DAD) and National Ambulatory Care Reporting System (NACRS) (18–21). We also determined case volumes and proportion of surgeries performed in DCs vs non-DCs and reported the above outcomes by institution.
Covariates and Statistical Analysis
Sex and age at the time of surgery were determined using the Registered Persons Database. Five-year inpatient records prior to surgery were used to calculate the Charlson co-morbidity index at the time of surgery (24). We tested differences in patient characteristics and surgical outcomes across eras, using logistic regression for binary variables and linear regression for continuous variables. We also compared outcomes by status of the performing hospital (DC vs non-DC) within each era. We used hierarchical logistic regression models to assess the association between standardization eras or institution types and 30- and 90-day mortalities with adjustment for covariates. Linear models with negative binomial distribution were used for estimating LOS. We adjusted for patient age as a continuous variable, and sex and Charlson co-morbidity index (<2 vs ≥2) as categorical variables. These models accounted for clustering within hospitals and estimates were derived using robust standard errors.
Interrupted time-series (ITS) analyses were performed to assess the impact of policy change on outcomes, while accounting for secular trends (i.e., the baseline rate of change that existed independent of the standardization policy). A time variable (6-month intervals of the fiscal year) was used to test for baseline trends, immediate impact on outcome level, and change in post interruption trend compared to the baseline. Testing for autocorrelation between variables in our time series models did not yield significant results.
Results
Patient and Hospital Characteristics
A total of 7,904 hepatectomies and 5,238 PDs were performed between 2003 to 2019 (Table 1). 1,237 (15.7%) hepatectomies were performed prior to standardization (2003–2006), 2,142 (27.1%) during standardization (2007–2011), and 4,525 (57.3%) after standardization (2012–2019). Similarly, 859 (16.4%) PDs were performed before standardization, 1,323 (25.3%) during standardization, and 3,056 (58.3%) in the post-standardization era. Distribution of age, sex and comorbidity burden was comparable over time (Table 1).
Table 1:
Baseline Characteristics of Patients and Performing Hospitals
| Hepatectomy | Pancreaticoduodenectomy | |||||||
|---|---|---|---|---|---|---|---|---|
| Outcome | Pre-Standardization (2003–2007) | Standardization (2007–2012) | Post-Standardization (2012–2019) | P-value | Pre-Standardization (2003–2007) | Standardization (2007–2012) | Post-Standardization (2012–2019) | P-value |
| N (%) | 1237 (15.7) | 2142 (27.1) | 4525 (57.3) | 859 (16.4) | 1323 (25.3) | 3056 (58.3) | ||
| Sex | ||||||||
| Male | 761 (61.5) | 1293 (60.4) | 2732 (60.4) | 498 (58) | 769 (58) | 1710 (56) | ||
| Female | 476 (38.5) | 849 (39.6) | 1793 (39.6) | 361 (42) | 554 (42) | 1346 (44) | ||
| Age | ||||||||
| Median (IQR) Mean (SD) | 63 (54.2–71) | 63.9 (55.7–71.9) | 64.8 (56.3–72.4) | 66.1 (57.8–73.7) | 66.3 (58.3–74) | 67.1 (59.5–74.5) | ||
| 62.1 (11.7) | 63.1 (11.7) | 63.7 (11.6) | 65.3 (10.6) | 65.2 (11.2) | 66.3 (10.6) | |||
| CCI ≥2a (%) | 1059 (85.6) | 1837 (85.8) | 3734 (82.5) | 406 (47.3) | 669 (50.6) | 1534 (50.2) | ||
| Performed at DC (%) | 1068 (86.3) | 1989 (92.9) | 4469 (98.8) | <0.001 | 710 (82.7) | 1184 (89.5) | 3045 (99.6) | <0.001 |
| Annual volumes (all hospitals) | <0.001 | |||||||
| Median (IQR) | 37 (20–117) | 55 (23–128) | 66 (46–121) | 21 (10–36) | 31 (17–70) | 50 (34–67) | <0.001 | |
| Mean (SD) | 63 (48) | 71 (49) | 80 (41) | 25 (19) | 39 (25) | 53 (26) | ||
| Categorized volumes (all hospitals, % | <0.001 | |||||||
| 0–5 | 63 (5.1) | 44 (2.1) | 44 (1.0) | 102 (11.9) | 49 (3.7) | 9 (0.3) | <0.001 | |
| 6–19 | 233 (18.8) | 316 (14.8) | 206 (4.6) | 300 (34.9) | 285 (21.5) | 303 (9.9) | ||
| 20+ | 941 (76.1) | 1782 (83.2) | 4275 (94.5) | 457 (53.2) | 989 (74.8) | 2744 (89.8) | ||
| Annual volumes (DCs) | <0.001 | <0.001 | ||||||
| Median (IQR) | 55 (29–117) | 69 (28–128) | 67 (47–121) | 22 (14–38) | 34 (22–71) | 50 (34–67) | ||
| Mean (SD) | 70 (48) | 76 (48) | 81 (40) | 29 (18) | 42 (24) | 53 (26) | ||
| Annual volumes (non-DCs) | ||||||||
| Median (IQR) | 20 (8–25) | 14 (6–17) | 6 (1–7) | 5 (3–8) | 10 (7–17) | 8 (1–8) | ||
| Mean (SD) | 17 (10) | 12 (6) | 5 (3) | 5 (3) | 11 (6) | 6 (3) | ||
| 30-d mortality (%) | 32 (2.6) | 51 (2.4) | 105 (2.3) | 0.9 | 31 (3.6) | 33 (2.5) | 73 (2.4) | 0.1 |
| 90-d mortality (%) | 51 (4.1) | 98 (4.6) | 200 (4.4) | 0.8 | 54 (6.3) | 64 (4.8) | 132 (4.3) | 0.06 |
| Length of stay (d) | <0.001 | <0.001 | ||||||
| Median (IQR) | 8 (6–10) | 7 (5–9) | 6 (4–8) | 14 (10–22) | 12 (8–18) | 9 (7–15) | ||
| Mean (SD) | 10 (8) | 10 (16) | 8 (9) | 19 (16) | 17 (15) | 13 (12) | ||
CCI: Charlson Comorbidity Index
DC: designated center
Median annual volumes across all performing hospitals increased significantly after standardization for both hepatectomy (37 vs. 66 cases) and PD (21 vs. 50 cases; p<0.0001). A total of 26, 27, and 25 unique hospitals were performing hepatectomy and/or PD before, during, and after standardization, respectively. This includes fringe hospitals performing any number of the index procedures during each standardization era. Overall, standardization was associated with a rise in the proportion of high-volume hospitals (performing at least 20 index cases) (Table 1). Overall, 86% and 83% of hepatectomies and PD, respectively, were performed at a DC before 2006. After standardization, this increased to 98.8% and 99.6% of all cases, respectively (Table 1).
There was a significant difference in the median number of hepatectomies being performed at each DC (55 cases/year vs. 67 cases/year) and non-DC (20 cases/year vs. 6 cases/year), before and after standardization (p <0.001). A similar trend in PD case volumes was observed across DCs (22 cases/year vs. 50 cases/year), before and after standardization (p<0.001). Median annual volume per non-DC was five PDs (IQR 3–8) before standardization, and eight (IQR 1–8) after standardization (Table 1).
Outcomes by Time Period
Crude 30-day mortality following hepatectomy was 2.6% (95% CI 1.8–3.7%) before, and 2.3% (95% CI 1.9–2.8%) after standardization (p=0.9). Crude 90-day mortality for hepatectomy was 4.1% (95% CI 3.1–5.4%) before, and 4.4% (95% CI 3.9–5.1%) after standardization (p=0.8; Table 1). The adjusted odds of 30- and 90-day mortality after hepatectomy were comparable over time (Table 2). Crude 30-day mortality rate after Whipple was 3.6% (95%CI 2.5–5.1%) before, and 2.4% (95%CI 1.9–3%) after standardization (p=0.1). Crude 90-day mortality after Whipple was 6.3% (95% CI 4.8–8.2%) before standardization, compared to 4.3% (95% CI 3.6–5.1%) after (p=0.06; Table 1). On multivariable analysis, the only notable difference observed was in 90-day mortality following Whipple, in the post-standardization era (4.3%), compared to before standardization (6.3%; aOR 0.7, 95%CI 0.5–0.9, p=0.03; Table 2). Median LOS was significantly lower after standardization for hepatectomy (6 days vs. 8 days) and Whipple procedures (9 days vs. 14 days; p<0.001) (Table 1 and 2).
Table 2:
Clinical Outcomes by Era of Standardization
| Hepatectomy | Pancreaticoduodenectomy | |||
|---|---|---|---|---|
| Outcome | Adjusted OR (95%CI) | P-value | Adjusted OR (95%CI) | P-value |
| Pre-standardization | Reference | |||
| 30-day mortality | ||||
| 90-day mortality | ||||
| Length of stay | ||||
| Standardization | ||||
| 30-day mortality | 0.9 (0.6–1.2) | 0.4 | 0.7 (0.5–1.1) | 0.1 |
| 90-day mortality | 1.0 (0.8–1.4) | 0.9 | 0.8 (0.5–1.1) | 0.2 |
| Length of stay | 1.0 (0.9–1.1) | 0.8 | 0.9 (0.8–1.0) | <0.001 |
| Post-standardization | ||||
| 30-day mortality | 0.8 (0.5–1.3) | 0.3 | 0.6 (0.4–1.0) | 0.05 |
| 90-day mortality | 0.9 (0.6–1.4) | 0.7 | 0.7 (0.5–0.9) | 0.03 |
| Length of stay | 0.8 (0.7–0.9) | <0.001 | 0.7 (0.6–0.8) | <0.001 |
Outcomes by Institution Type
DCs reported significantly lower odds of 30-day (aOR 0.5, 95% CI 0.3–0.9, p=0.03) and 90-day (aOR 0.5, 95% CI 0.3–0.9, p=0.02) mortality after hepatectomy, compared to non-DCs, in the pre-standardization era. No differences were observed in the adjusted risk ratio of LOS at DCs vs non-DCs before standardization.
DCs performed significantly better than non-DCs with respect to 90-day mortality after PD, in the pre-standardization era (aOR 0.6, 95% CI 0.3–1.0, p=0.03). Risk of 30-day mortality after PD was comparable between DC and non-DCs before standardization (aOR 0.7, 95%CI 0.3–1.8, p=0.5). Adjusted risk ratio for LOS after PD was significantly lower in DCs, for all three eras.
Impact of Standardization Over Time
Interrupted time series models revealed a significant baseline trend in the proportion of hepatectomies (1.1, 95%CI 0.5–1.7, p<0.01) and PD (2.0, 95%CI 1.1–3.0, p<0.01) being performed at DCs before 2006 (Table 3). Introduction of the Standards was associated with further rise, albeit at a slower rate, in the number of hepatectomies and PDs being performed at a DC (Table 3; Figure 1). All other immediate and late effects on mortality and LOS were explained by secular trends, which pre-dated the introduction of the Surgical Oncology Standards (Table 3; Figure 1).
Table 3:
Immediate and Delayed Effects of Standardizationa
| Hepatectomy | Pancreaticoduodenectomy | |||
|---|---|---|---|---|
| Outcome | Ratio (95%CI) | P-value | Ratio (95%CI) | P-value |
| 30-day mortality | ||||
| Baseline trend | −0.3 (−0.6–0.02) | 0.08 | 0 (−0.5–0.5) | 1.0 |
| Immediate intervention effect | 0.8 (−0.8–2.3) | 0.35 | −0.9 (−3.1–1.3) | 0.4 |
| Change from baseline trend | 0.3 (−0.01–0.6) | 0.07 | −0.01 (−0.5–0.4) | 1.0 |
| 90-day mortality | ||||
| Baseline trend | −0.2 (−0.6–0.1) | 0.2 | −0.2 (−0.5–0.1) | 0.3 |
| Immediate intervention effect | 1.6 (−0.2–3.5) | 0.1 | 0.5 (−1.1–2.1) | 0.5 |
| Change from baseline trend | 0.2 (−0.2–0.6) | 0.3 | 0.2 (−0.2–0.5) | 0.3 |
| Length of stay | ||||
| Baseline trend | −0.2 (−0.5–0.1) | 0.2 | −0.2 (−0.5–0.2) | 0.4 |
| Immediate intervention effect | 1.9 (0.4–3.4) | 0.02 | −0.6 (−2.4–1.3) | 0.6 |
| Change from baseline trend | 0.04 (−0.3–0.4) | 0.8 | −0.1 (−0.5–0.3) | 0.6 |
| Performed at Designated Center | ||||
| Baseline trend | 1.1 (0.5–1.7) | 0 | 2.0 (1.1–3.0) | 0 |
| Immediate intervention effect | 1.5 (−1.6–4.6) | 0.4 | −1.9 (−6.6–2.7) | 0.4 |
| Change from baseline trend | −0.7 (−1.4– −0.1) | 0.04 | −1.4 (−2.4– −0.4) | 0.01 |
Pre-standardization vs. standardization and post-standardization eras
Figure 1:
Immediate and delayed effects of standardization on 30-day mortality (I), 90-day mortality (II), and volumes at designated centers (III), for Hepatectomy (A) and Pancreaticoduodenectomy (B).
Discussion
We performed a population level analysis of clinical outcomes and organization of care for patients having HPB surgery prior to the introduction of Surgical Oncology HPB Standards (2003–6) during implementation of the standards (2007–12) and post implementation (2013–2019) in the province of Ontario, Canada. 57% of all included procedures were performed after standardization. Median annual case volumes in the post-standardization era were 67 hepatectomies and 50 PDs per hospital, with 99% of all cases performed at a DC. Crude 30-day mortality in the post implementation period was 2.3% after hepatectomy and 2.4% after PD, respectively. There was a significant reduction in 90-day mortality after PD (4.3% vs. 6.3%) and median length of stay after PD (9 days vs. 14 days) and hepatectomy (6 days vs. 8 days) in the post-standardization cohort, compared to before standardization. Differences in mortality and LOS over time; however, were likely attributable to secular trends that pre-dated the policy change.
Many studies have demonstrated a favorable relationship between higher case volumes and outcomes after complex oncologic surgery (1, 3, 6–14, 25, 26). This has led to increasing centralization of specialized cancer services, including HPB surgery, throughout North America and Europe (5–14, 27–31). Schneider et al. (2014) conducted a retrospective examination of volume and outcomes after HPB surgery, using SEER-Medicare linked data between 1986 to 2002 (7). Their analysis revealed an index mortality rate of 10.5% at low-volume, and 5.4% at high-volume hospitals. The authors defined high volume as ≥11 cases/year including all pancreatic, hepatic, and biliary procedures (7). Despite initiatives such as “Take the Volume Pledge” and “Leapfrog”, there remains variation in organizational models and degree of centralization of HPB surgery within the United States (27). A more contemporary SEER-Medicare analysis of outcomes after Whipple demonstrated 90-day mortality rates of 3.9% in high volume scenarios, which consisted of ≥9 cases per hospital/year and ≥5 cases per surgeon/year (28). In Ontario, HPB centers are expected to carry out a minimum of 50 index HPB cases per year, including at least 20 pancreatic resections (17). During the study period, annual case volumes in Ontario exceeded this threshold with excellent quality-based outcomes over a 16-year period.
Several European jurisdictions have also demonstrated excellent outcomes with central regulation of complex HPB surgery, across large geographic areas and within a publicly funded healthcare system (10–14, 32). In Norway (population of 5.3 million), 90-day mortality after PD across five teaching hospitals has been reported at 4%, with annual volumes of 84 to 513 cases per hospital (14). Similarly, a Dutch nationwide audit of mortality after PD demonstrated in-hospital mortality rates of 4%, with the best outcomes observed in high volume hospitals (≥40 cases per year) (10, 11). Bassi et al. (2022) published a retrospective analysis of 3000 consecutive cases performed at the Verona Pancreas Institute, where annual volumes exceeded 200 cases in 2019. They reported a 3% in-hospital mortality rate between 2010–2019, with 30-day mortality rates ranging from 2–3% (32). Taken together, these outcomes are consistent with those observed in our jurisdiction and, superior to other national cohorts, which may be subject to a lower a degree of centralization (33, 34).
With respect to organization of care, we noted a significant concentration of complex HPB surgery at DCs (>80%) prior to the implementation of the Surgical Oncology Standards in 2006. This is likely attributable to pre-existing provincial quality improvement initiatives and may have attenuated the effect of formal standardization efforts in 2006 on quality outcomes (5). CCO, in fact, first defined criteria for the delivery of pancreatic surgery in 1999, outlining the necessary volumes of both major pancreatic (>10 cases/year) and total HPB surgery (>25 cases/year). This, however, did not include any formal implementation of organizational standards. The period between 2002–2004 was characterized by a major redistribution of pancreatic surgery, with a shift in case volumes to medium (10–19 cases/year) and high volume (>20 cases/ year) centers. This was associated with a decrease in operative mortality from 3–10% to 2–6% across the different volume categories (5). Nearly 40% of pancreatic cases between 2002 and 2004; however, continued to occur in low volume centers, where mortality rates exceeded 6% (5). This is congruent with our findings, where DCs reported significantly lower rates of 90-day mortality than non-DCs, in the pre-standardization era. Introduction of the Standards in 2006 (mandating a minimum of 50 index HPB cases per year, including at least 20 pancreatic resections) led to increased concentration and access to care at high volume centers across the province. This was reflected as a proportional rise in annual case volumes (i.e., >50% of total cases) between 2012–2019, a large majority of which were performed at a DC.
Improved outcomes are likely related to a multitude of factors, including increased access to specialized surgical care, advances in systemic therapy and medical oncologists with specialized interest in HPB cancers, perioperative optimization, and development of surgical and post-surgical expertise with a greater willingness to offer surgery (25–28). An incremental rise in case volumes also affords, both the surgeon, and multidisciplinary team, opportunities to develop and maintain expertise as well as undertake quality improvement activities as a result of a critical volume of cases. In Ontario, this was coupled with mandatory tracking of performance indicators by CCO and knowledge translation initiatives within the HPB communities of practice (COP), which promoted further optimization of institutional level quality-based outcomes over time (17, 35).
High surgical volume; however, doesn’t necessarily beget high quality outcomes. A critical component of defining Standards for HPB surgery in Ontario was developing a robust ecosystem of physical and human resources with expert training needed for the complete spectrum of patient care. This includes specialized teams with nursing personnel capable of managing complex abdominal surgical problems, intensive care, anesthesiologists, multidisciplinary cancer care, and designation within a regional cancer center (17, 36). The low mortality rates observed in our cohort also underscore the importance of timely detection and management of complications. Around-the-clock availability of diagnostic and interventional radiology, as well as therapeutic endoscopy with staff skilled in HPB interventions is a key component of rescue from complications to minimize mortality (10, 37). Another notable mandate was for all surgeons to obtain fellowship training in HPB surgery, liver transplant, or HPB surgical oncology, which may not be case in other jurisdictions (38). Concerns about increased wait times to seek expert care in a regionalized system have not borne out in the literature (15, 39). In Ontario, wait times for all cancer surgeries have improved by 30%, from 81 days in 2005 to 57 days in 2010 (35). The current provincial wait time goal for HPB surgery is 28 days, measured from the time of consent. This is, in part, due to impetus provided by a provincial wait times strategy with public reporting to increase accountability and transparency. The Surgical Oncology Program at CCO also implemented a COP as a mechanism to support knowledge transfer, uptake of evidence-based guidelines, and facilitate the sharing of expertise across the province (35). These relationships and communities also serve a foundation for triage and sharing of cases to further mitigate wait times and improve access to timely surgical care.
Our findings are limited by coding inaccuracies inherent to administrative datasets. The retrospective nature of the study is also subject to selection bias, although we observed no significant differences in baseline characteristics between groups. The primary outcomes in this study were consistent with guidelines from regulatory agencies, which use crude in-hospital and 30-day mortality for benchmarking and quality assurance (17). These parameters, however, can be subject to bias due to lower event rates and individual risk profiles of patients (40, 41). We attempted to mitigate this by using risk-adjusted 30- and 90-day mortality rates for a more nuanced understanding of quality and performance across regionalization eras. Other patient-centered hospital-level quality indicators, including morbidity, failure to rescue, and readmission rates were not examined in this analysis. We also did not analyze point distances and travel time due to a high proportion of missing data (44% for hepatectomy and 34% for PD) in the Postal Code Conversion File available from Statistics Canada. Patient transfers from remote locations, or incremental increases in travel time due to regionalization have not shown to be prohibitive for patients in accessing high quality care for other disease sites in our province (15, 39).
Conclusions
Provincial standardization of complex HPB surgery was associated with a higher volume of hepatectomy and PD, lower LOS and improved 90-day mortality after PD. The present study adds value to the existing body of literature by demonstrating the merits of a multi-faceted and well-regulated system, across a wide geographic area, in consistently achieving excellent quality-based outcomes after complex oncologic surgery.
Acknowledgement
The authors would like to acknowledge the significant contributions of Dr. Robin McLeod for her leadership of this provincial initiative and Leigh McKnight for her support in developing quality indicators.
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