The effect of hospital factors on mortality rates after abdominal aortic aneurysm repair

From Emergency Room to Operating Room: Multidisciplinary Simulation Training in Emergency Laparotomy for Ruptured Abdominal Aortic Aneurysm - Learning Outcomes and Costs

BACKGROUND

Opportunities to practice emergency laparotomy (EL) and open surgical repair (OSR) for a ruptured abdominal aortic aneurysm (rAAA) are limited. While simulation-based training (SBT) is effective in educating healthcare professionals in medical emergencies, SBT specifically in EL and OSR for rAAA is scarce. It takes a team to diagnose a patient with massive abdominal bleeding, such as in rAAA, to organize primary care, and to provide definite treatment without unnecessary delays. This study investigated the effects of multidisciplinary EL simulation training in OSR for rAAA, from the emergency room (ER) to the operating room (OR), on trainees' learning outcomes and the costs of the training.

METHODS

A total of 162 healthcare professionals in 21 simulated emergency laparotomy teams participated in a structured 2-hour course consisting of an introductory lecture and a simulation scenario followed by debriefing. Data were collected using a pre-post self-assessment questionnaire and the T-NOTECHS scale. Implementation costs and the cost of education were calculated.

RESULTS

Simulation training improved knowledge, skills, and attitudes of both physicians and nurses. Most of the non-technical skills studied were significantly enhanced in both professional groups. The total cost of the simulation training was €29 415, cost per team €1,400 and cost per participant €182.

CONCLUSIONS

Multidisciplinary EL simulation training in OSR for rAAA from the ER to the OR is effective in improving knowledge, skills, and attitudes, as well as non-technical skills among both physicians and nurses. The overall costs of training seem reasonable given the significant learning outcomes.

Racial and sex disparities in inpatient outcomes of patients with ruptured abdominal aortic aneurysms in the United States

BACKGROUND

Ruptured abdominal aortic aneurysm (AAA) is a medical emergency that requires immediate surgical intervention. The aim of this analysis was to identify the sex- and race-specific disparities that exist in outcomes of patients hospitalized with this condition in the United States using the National Inpatient Sample (NIS) to identify targets for improvement and support of specific patient populations.

METHODS

In this descriptive, retrospective study, we analyzed the patients admitted with a primary diagnosis of ruptured AAA between January 1, 2016, and December 31, 2020, using the NIS database. We compared demographics, comorbidities, and in-hospital outcomes in AAA patients, and compared these results between different racial groups and sexes.

RESULTS

A total of 22,395 patients with ruptured AAA were included for analysis. Of these, 16,125 patients (72.0%) were male, and 6270 were female (28.0%). The majority of patients (18,655 [83.3%]) identified as Caucasian, with the remaining patients identifying as African American (1555 [6.9%]), Hispanic (1095 [4.9%]), Asian or Pacific Islander (470 [2.1%]), or Native American (80 [0.5%]). Females had a higher risk of mortality than males (OR, 1.7; 95% confidence interval [CI], 1.45-1.96; P < .001) and were less likely to undergo endovascular aortic repair (OR, 0.70; 95% CI, 0.61-0.81; P < .001) or fenestrated endovascular aortic repair (OR, 0.71; 95% CI, 0.55-0.91; P = .007). Relative to Caucasian race, patients who identified as African American had a lower risk of inpatient mortality (OR, 0.50; 95% CI, 0.37-0.68; P < .001).

CONCLUSIONS

In this retrospective study of the NIS database from 2016 to 2020, females were less likely to undergo endovascular intervention and more likely to die during their initial hospitalization. African American patients had lower rates in-hospital mortality than Caucasian patients, despite a higher burden of comorbidities. Future studies are needed to elucidate the potential factors affecting racial and sex disparities in ruptured AAA outcomes, including screening practices, rupture risk stratification, and more personalized guidelines for both elective and emergent intervention.

Adoption and clinical outcomes of fenestrated endovascular aneurysm repair in a regional, multistate community hospital system

OBJECTIVE

Complex endovascular abdominal aortic aneurysm (AAA) repair techniques have evolved over the last decade, yet patterns of physician and hospital system adoption of fenestrated endovascular aneurysm repair (FEVAR) remain poorly defined. We investigated clinical outcomes, use trends, and surgeon and hospital experience for FEVAR in a large community hospital system.

METHODS

We conducted a retrospective cohort study of all FEVAR procedures within our 5-state hospital system between April 2012 and June 2021. AAA repair volumes (open, EVAR, and FEVAR) were captured at the hospital and surgeon levels using Current Procedural Terminology and International Classification of Diseases codes. Clinical and outcomes data were collected for FEVAR patients. To consider if surgeon or hospital experience influenced outcomes, sequential case number was used to divide patients into surgeon experience and hospital experience groups. Inverse probability weighted and generalized linear mixed models, adjusted for demographics and comorbidities, were built to examine risk-adjusted outcomes for surgeon and hospital experience groups.

RESULTS

Of 3850 patients treated with AAA procedures of any kind between 2012 and 2021, 160 (4.2%) underwent FEVAR. FEVAR procedures were performed by 34 different surgeons at 12 hospitals, with intraoperative complications and unplanned adjunctive procedures occurring in 18.8% (n = 30) and 19.4% (n = 31) of patients, respectively. Among FEVAR patients, in-hospital mortality was 1.3% (n = 2) and postoperative morbidity was 16.9% (n = 27). Renal function decline occurred postoperatively in 5.1% of patients. Early (<30 day) postoperative endoleaks occurred in 15.3% of patients (n = 21). Target vessel patency was 95.6% on initial postoperative imaging. Surgeon and hospital experience had a small positive impact on outcomes after the first one to three cases. Significant decreases in operative time, fluoroscopy time, and estimated blood loss were observed with increased surgeon experience, relative to a surgeon's first case (P < .05). There were lower odds of intraoperative complications after a surgeon's first case (odds ratio [OR], 0.16; 95% confidence interval [CI], 0.03-0.77, for cases 2-3) or after a hospital's first one to three cases (OR, 0.19; 95% CI, 0.04-0.89, for cases 4-8; OR, 0.12; 95% CI, 0.03-0.55 for cases 9-49).

CONCLUSIONS

Clinical outcomes of FEVAR across our hospital system compare favorably with previously published reports. Although system-wide FEVAR adoption increased 3-fold over the last decade, FEVAR continued to be performed by a minority of hospitals in our system. The results from this cohort demonstrate low rates of adverse events, high rates of technical efficiency, and a small impact of surgeon and hospital experience, thereby supporting this advanced endovascular technology as a safe, efficacious, and generalizable treatment alternative to open repair for patients with complex aortic anatomy.

[Recommendations for the specialist further training of nursing personnel on intensive care units in the treatment of abdominal aortic aneurysms: results of a modified Delphi procedure with experts]

INTRODUCTION

The medical development in the previous 15 years and the changes in treatment reality of the comprehensive elective treatment of abdominal aortic aneurysms necessitate a re-evaluation of the quality assurance guidelines of the Federal Joint Committee in Germany (QBAA-RL). In the current version this requires a specialist further training quota for nursing personnel in intensive care wards of 50%. The quota was determined in 2008 based on expert opinions, although a direct empirical evidence base for this does not exist.

METHODS

Representatives from the fields of patient representation, physicians, nursing personnel and other relevant interface areas were invited to participate in a modified Delphi procedure. Following a comprehensive narrative literature search, a survey and focus group discussions with national and international experts, a total of three anonymized online-based voting rounds were carried out for which previously determined key statements were assessed with a 4‑point Likert scale (totally disagree up to totally agree). In addition, the expert panel had also defined a recommendation for a minimum quota for the specialist training of nursing personnel on intensive care wards in the treatment of abdominal aortic aneurysms, whereby an a priori agreement of 80% of the participants was defined as the consensus limit.

RESULTS

Overall, 37 experts participated in the discussions and three successive voting rounds (participation rate 89%). The panel confirmed the necessity of a re-evaluation of the guideline recommendations and recommended the introduction of a shift-related minimum quota of 30% of the full-time equivalent of nursing personnel on intensive care wards and the introduction of structured promotional programs for long-term elevation of the quota.

CONCLUSION

In this national Delphi procedure with medical and nursing experts as well as representatives of patients, the fundamental benefits and needs of professional specialist qualifications in the field of intensive care medicine were confirmed. The corresponding minimum quota for specialist further training of intensive care nursing personnel should generally apply without limitations to specific groups. The expert panel stipulates a shift-related minimum quota for intensive care nursing personnel with specialist training of 30% of the nursing personnel on intensive care wards and the obligatory introduction of structured and transparent promotion programs for the long-term enhancement.

Decreasing prevalence of centers meeting the Society for Vascular Surgery abdominal aortic aneurysm guidelines in the United States

OBJECTIVE

Based on data supporting a volume-outcome relationship in elective aortic aneurysm repair, the Society of Vascular Surgery (SVS) guidelines recommend that endovascular aortic repair (EVAR) be localized to centers that perform ≥10 operations annually and have a perioperative mortality and conversion-to-open rate of ≤2% and that open aortic repair (OAR) be localized to centers that perform ≥10 open aortic operations annually and have a perioperative mortality ≤5%. However, the number and distribution of centers meeting the SVS criteria remains unclear. This study aimed to estimate the temporal trends and geographic distribution of Centers Meeting the SVS Aortic Guidelines (CMAG) in the United States.

METHODS

The SVS Vascular Quality Initiative was queried for all OAR, aortic bypasses, and EVAR from 2011 to 2019. Annual OAR and EVAR volume, 30-day elective operative mortality for OAR or EVAR, and EVAR conversion-to-open rate for all centers were calculated. The SVS guidelines for OAR and EVAR, individually and combined, were applied to each institution leading to a CMAG designation. The proportion of CMAGs by region (West, Midwest, South, and Northeast) were compared by year using a χ2 test. Temporal trends were estimated using a multivariable logistic regression for CMAG, adjusting by region.

RESULTS

Overall, 67,865 patients (49,264 EVAR; 11,010 OAR; 7591 aortic bypasses) at 336 institutions were examined. The proportion of EVAR CMAGs increased nationally by 1.7% annually from 51.6% (n = 33/64) in 2011 to 67.1% (n = 190/283) in 2019 (β = .05; 95% confidence interval [CI], 0.01-0.09; P = .02). The proportion of EVAR CMAGs across regions ranged from 27.3% to 66.7% in 2011 to 63.9% to 72.9% in 2019. In contrast, the proportion of OAR CMAGs has decreased nationally by 1.8% annually from 32.8% (n = 21/64) in 2011 to 16.3% (n = 46/283) in 2019 (β = -.14; 95% CI, -0.19 to -0.10; P < .01). Combined EVAR and OAR CMAGs were even less frequent and decreased by 1.5% annually from 26.6% (n = 17/64) in 2011 to 13.1% (n = 37/283) in 2019 (β = -.12; 95% CI, -0.17 to -0.07; P < .01). In 2019, there was no significant difference in regional variation of the proportion of combined EVAR and OAR CMAGs (P = .82).

CONCLUSIONS

Although an increasing proportion of institutions nationally meet the SVS guidelines for EVAR, a smaller proportion meet them for OAR, with a concerning downward trend. These data question whether we can safely offer OAR at most institutions, have important implications about sufficient OAR exposure for trainees, and support regionalization of OAR.

Trends in Hospital Admissions, Operative Approaches, and Mortality Related to Abdominal Aortic Aneurysms in England Between 1998 and 2020

OBJECTIVE

To assess trends in abdominal aortic aneurysm (AAA) hospital admissions, interventions, and aneurysm related mortality in England, and to examine the impact of endovascular repair on mortality for the years 1998 - 2020.

METHODS

Hospital admission and operative approach (endovascular aortic aneurysm repair, or open surgical repair [OSR]) using Hospital Episodes Statistics (HES), and aneurysm related mortality data from the Office for National Statistics for England standardised to the 2013 European Standard Population, were analysed using linear regression and Joinpoint regression analyses. Aneurysm related mortality was compared between the pre-endovascular era (1998 - 2010) and the endovascular era (2011 - 2019).

RESULTS

A declining trend in hospital admission incidence was observed, mainly due to a decline in ruptured admissions from 34.6 per 100 000 (95% confidence interval [CI] 33.5 - 35.6) to 13.5 per 100 000 (95% CI 12.9 - 14.2; βi = -1.04, r2 = .97, p < .001). Operative interventions have been declining over the last 23 years mainly due to the statistically significant decline in open procedures (41.2 per 100 000 in 2000 [95% CI 40 - 42.3] to 9.6 per 100 000 [95% CI 9.1 - 10.1]; βi = -1.92, r2 = .95; p < .001). There was an increasing trend toward endovascular procedures (5.8 per 100 000 [95% CI 5.3 - 6.2] in 2006 to 16.9 per 100 000 [95% CI 16.2 - 17.5] in 2020; βi = .82, r2 = .30, p = .040). Reductions in aneurysm related mortality due to AAAs were observed for males and females, irrespective of age and rupture status.

CONCLUSION

A significant decrease in hospital admissions for AAAs was observed over the last 23 years in England, paralleled by a shift toward endovascular repair and a decline in OSR. Declines in aneurysm related mortality were observed overall, and in the endovascular era irrespective of age, sex, and rupture status.

Surgeon volume and established hospital perioperative mortality rate together predict for superior outcomes after open abdominal aortic aneurysm repair

BACKGROUND

In 2018, the Society for Vascular Surgery (SVS) published hospital volume guidelines for elective open abdominal aortic aneurysm (AAA) repair, recommending that elective open surgical repair of AAAs should be performed at centers with an annual volume of ≥10 open aortic operations of any type and a documented perioperative mortality of ≤5%. Recent work has suggested a yearly surgeon volume of at least seven open aortic cases for improved outcomes. The objective of the present study was to assess the importance of hospital volume and surgeon volume at these cut points for predicting 1-year mortality after open surgical repair of AAAs.

METHODS

We evaluated patients who had undergone elective open AAA repair using the New York Statewide Planning and Research Cooperative System database from 2003 to 2014. The effect of the SVS guidelines on postoperative mortality and complications was evaluated. Confounding between the hospital and surgeon volumes was identified using mixed effects multivariate Cox proportional hazards analysis. The effect of the interactions between hospital volume, established hospital perioperative survival, and surgeon volume on postoperative outcomes was also investigated.

RESULTS

The cohort consisted of 7594 elective open AAA repairs performed by 542 surgeons in 137 hospitals during the 12-year study period. Analysis of the 2018 guidelines using the Statewide Planning and Research Cooperative System database revealed 1-year and 30-day mortality rates of 9.2% (range, 8.3%-10.1%) and 3.5% (range, 2.9%-4.1%) for centers that were within the SVS guidelines and 13.6% (range, 12.5%-14.7%) and 6.9% (range, 6.1%-7.8%) for those that were outside the guidelines, respectively (P < .001 for both). Multivariate survival analysis revealed a hazard ratio for a surgeon volume of ≥7, hospital volume of ≥10, and hospital 3-year perioperative mortality of ≤5% of 0.80 (95% confidence interval [CI], 0.70-0.93; P = .003), 0.91 (95% CI, 0.77-1.08; P = .298), and 0.72 (95% CI, 0.62-0.82; P < .001), respectively. Additionally, procedures performed by surgeons with a yearly average volume of open aortic operations of at least seven and at hospitals with an established elective open AAA repair perioperative mortality rate of ≤5% showed improved 1-year (33.2% relative risk reduction; P < .001) and 30-day (P = .001) all-cause survival and improved postoperative complication rates.

CONCLUSIONS

These data have demonstrated that centers that meet the SVS AAA volume guidelines are associated with improved 1-year and 30-day all-cause survival. However, the results were confounded by surgeon volume. A surgeon open aortic volume of at least seven procedures and an established hospital perioperative mortality of ≤5% each independently predicted for 1-year survival after open AAA repair, with the hospital volume less important. These results indicate that surgeons with an annual volume of at least seven open aortic operations of any type should perform elective open AAA repair at centers with a documented perioperative mortality of ≤5%.

[Case load and quality indicators in the treatment of abdominal aortic aneurysms]

BACKGROUND

The MTL30 (mortality, transfer, length of stay) was proposed as a surrogate parameter for evaluating the quality of large and potentially complication-prone visceral surgical interventions.

OBJECTIVE

The aim of this study was to find out to what extent the MTL30 can be correlated with the results of the abdominal aortic aneurysm (AAA) registry of the German Institute for Vascular Health Research (DIGG) of the German Society for Vascular Surgery and Vascular Medicine (DGG) and with the case volume of the participating hospitals.

MATERIAL AND METHODS

Elective endovascular abdominal aortic aneurysm repair (EVAR) was performed in 14,282 patients and open repair (OAR) in 3923 patients. Case volume of the treating hospitals, hospital mortality, length of stay and transfer to another acute care hospital were determined 30 days after the index intervention.

RESULTS

The hospital mortality was 1.3% for EVAR and 4.9% for OAR (p = 0.000), the MTL30 was 5.0% and 14.4%, respectively (p = 0.000). For EVAR, no relationship between case volume and hospital mortality (quintile 1: 1.0%; quintile 5: 1.3%) as well as case volume and MTL30 (quintile 1: 5.3%; quintile 5: 5.3%) could be demonstrated. Also in OAR there was no significant relationship between case volume and hospital mortality (quintile 1: 5.8%, quintile 5: 3.5%; p = 0.505) and case volume and MTL30 (quintile 1: 16.4%, quintile 5: 12.2%, p = 0.110). With a hospital mortality rate of 7.2% (5-10%) the MTL30 for OAR was 17.6%. In both EVAR and OAR, the length of stay correlated significantly with hospital mortality and MTL30.

DISCUSSION

A clear relationship between hospital case volume and hospital mortality could not be shown in the AAA registry of the DIGG. The same was true for the MTL30. It remains to be seen whether the MTL30 offers an additional benefit compared to the recording of hospital mortality and inpatient length of stay as a quality parameter.

Editor's Choice - Systematic Review and Meta-Analysis of the Impact of Institutional and Surgeon Procedure Volume on Outcomes After Ruptured Abdominal Aortic Aneurysm Repair

OBJECTIVE

To investigate whether there is a correlation between institutional or surgeon case volume and outcomes in patients with ruptured abdominal aortic aneurysm (rAAA).

DATA SOURCES

The Healthcare Database Advanced Search interface developed by the National Institute of Health and Care Excellence was used to search MEDLINE, Embase, CINAHL, and CENTRAL.

REVIEW METHODS

The systematic review complied with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines with the protocol registered in PROSPERO (CRD42020213121). Prognostic studies were considered comparing outcomes of patients with rAAA undergoing repair in high and low volume institutions or by high and low volume surgeons. Pooled estimates for peri-operative mortality were calculated using the odds ratio (OR) and 95% confidence intervals (CI), applying the Mantel-Haenszel method. Analysis of adjusted outcome estimates was performed with the generic inverse variance method.

RESULTS

Thirteen studies reporting a total of 120 116 patients were included. Patients treated in low volume centres had a statistically significantly higher peri-operative mortality than those treated in high volume centres (OR 1.39; 95% CI 1.22 - 1.59). Subgroup analysis showed a mortality difference in favour of high volume centres for both endovascular aneurysm repair (EVAR; OR 1.61, 95% CI 1.11 - 2.35) and open repair (OR 1.50, 95% CI 1.25 - 1.81). Adjusted analysis showed a benefit of treatment in high volume centres for open repair (OR 1.68, 95% CI 1.21 - 2.33) but not for EVAR (OR 1.42, 95% CI 0.84 - 2.41). Differences in peri-operative mortality between low and high volume surgeons were not statistically significant for either EVAR (OR 1.06, 95% CI 0.59 - 1.89) or open surgical repair (OR 1.18, 95% CI 0.87 - 1.63).

CONCLUSION

A high institutional volume may result in a reduction of peri-operative mortality following surgery for rAAA. This peri-operative survival advantage is more pronounced for open surgery than EVAR. Individual surgeon caseload was not found to have a significant impact on outcomes.

A systematic review of the effect of surgeon and hospital volume on survival in aortic, thoracic and fenestrated endovascular aneurysm repair

BACKGROUND

Endovascular aneurysm repair (EVAR) is becoming a mainstay in vascular surgery, both in metropolitan and regional hospitals. This review aims to assess the impact of hospital and surgeon volume on perioperative mortality specific to this surgery type to support the use of this treatment modality extensively.

METHODS

A literature search was performed on multiple dedicated medical databases using a detailed search strategy with terms focusing on hospital volume and EVARs. Inclusion and exclusion criteria were used to screen and evaluate suitable sources, focusing on operators and hospitals performing EVARs and the morbidity/mortality as outcomes. The results were then appraised using a PRISMA framework.

RESULTS

We reviewed 45 articles. Twelve articles met inclusion criteria for complete review. There was no level 1 evidence, and only a single systematic review and meta-analysis. EVAR and thoracic EVAR perioperative mortality had no correlation with hospital volume. Limited evidence was presented for fenestrated EVAR, where a mortality risk based on hospital volume remains unanswered. Open procedures for aneurysm repair had perioperative mortality outcomes that grossly correlated with hospital volume, supporting their use in high-volume centers.

CONCLUSIONS

With open aneurysm repairs having an increased mortality risk in low-volume centers, and endovascular treatment options gaining momentum, there is considerable support for the use of EVAR and thoracic EVAR in smaller regional centers safely and effectively. There is very limited evidence in the use of fenestrated EVAR, which remains unanswered, but presents a significant opportunity for research.

Association between operation volume and postoperative mortality in the elective open repair of infrarenal abdominal aortic aneurysms: systematic review

Background

An inverse association between the case volume per hospital and surgeon and perioperative mortality has been shown for many surgical interventions. There are numerous studies on this issue for the open treatment of infrarenal aortic aneurysms.

Aim

To present the available data on the association between the case volume per hospital and surgeon and perioperative mortality in the elective open repair of infrarenal aortic aneurysms in a systematic review.

Materials and methods

Using the PubMed, Cochrane Library, Web of Science Core Collection, CINAHL, Current Contents Medicine (CCMed), and ClinicalTrials.gov databases, a systematic search was performed using defined keywords. From the search results, all original papers were included that compared the elective open repair of an infrarenal aortic aneurysm in a “high volume” center with a “low volume” center or by a “high volume” surgeon with a “low volume” surgeon, as defined in the respective study.

Results

After deduplication, the literature search yielded 1021 hits of which 60 publications met the inclusion criteria. Of these, 37/43 studies showed a lower mortality in “high volume” compared to “low volume” centers and 14/17 comparisons showed a lower mortality for “high volume” compared to “low volume” surgeons. The effect measures, usually odds ratios, ranged from 0.37 to 0.99 for volume per hospital and 0.31 to 0.92 for volume per surgeon. Regarding the threshold values for the definition of “high volume” and “low volume,” a clear heterogeneity was shown between the individual studies.

Discussion

The available data on the association between the case volume per hospital and surgeon and perioperative mortality in the elective open repair of infrarenal aortic aneurysms show that interventions performed in “high volume” centers or by “high volume” surgeons are associated with lower mortality. To ensure the best possible outcome in terms of low perioperative mortality in the open repair of infrarenal aortic aneurysms, the aim should be centralization with high case volume per hospital and surgeon.

Mortality for Open Abdominal Aortic Aneurysm Repair before and after Endovascular Aortic Repair (EVAR)

The purpose of this study was to determine whether endovascular aortic repair (EVAR) has impacted inhospital mortality for patients undergoing open repair (OR). From 1982 through 2016, 1572 repairs were performed for abdominal aortic aneurysms (AAAs). Both ORs and EVARs were performed by the author at two large, tertiary-care, community-based hospitals. In Period I (1982–1999, n = 863), all AAA repairs were performed open. In Period II (2000–2016; n = 709), repairs were performed both by ORs and EVARs. Demographics were similar between study groups. Mortality for elective repairs in Periods I and II were as follows: I = 1.2 per cent (open, n = 9/756) versus II = 1.7 per cent (open, n = 4/241) versus II = 1.2 per cent (EVAR, n = 5/420). Mortality for patients with ruptured AAAs in Periods I and II were as follows: I = 31.8 per cent (open, n = 34/107) versus II = 32 per cent (open, n = 8/25) versus II = 13 per cent (EVAR, n = 3/23). The results of this study demonstrate that the introduction of EVARs has not negatively impacted the inhospital mortality for elective ORs or emergent AAAs for one vascular surgeon who completed training before EVARs became available.

National temporal trends and determinants of cost of abdominal aortic aneurysm repair

INTRODUCTION

In recent decades, there has been a shift in the management of aortic abdominal aneurysm from open intervention (open aortic aneurysm repair) to an endovascular approach (endovascular aortic aneurysm repair). This shift has yielded clinical as well as socioeconomic reverberations. In our current study, we aim to analyze these effects brought about by the switch to endovascular treatment and to scrutinize the determinants of cost variations between the two treatment modalities.

METHODS

The National (Nationwide) Inpatient Sample database was queried for clinical data ranging from 2001 to 2013 using International Classification of Disease, 9th Revision (ICD-9) codes for open and endovascular aortic repair. Clinical parameters and financial data related to the two treatment modalities were analyzed. Temporal trends of index hospitalization costs were determined. Multivariate linear regression was used to characterize determinants of cost for endovascular aneurysm repair and open abdominal aortic aneurysm repair.

RESULTS

A total of 128,154 aortic repairs were captured in our analysis, including 62,871 open repairs and 65,283 endovascular repairs. Over the assessed time period, there has been a decrease in the cost of elective endovascular aortic aneurysm repair from $34,975.62 to $31,384.90, a $3,590.72 difference (p < 0.01), while the cost of open aortic repair has increased from $37,427.77 to $43,640.79 by 2013, a $6,212.79 increase (p < 0.01). The cost of open aortic aneurysm repair disproportionately increased at urban teaching hospitals, where by 2013, it costs $50,205.59, compared to $34,676.46 at urban nonteaching hospitals, and $34,696.97 at rural institutions. Urban teaching hospitals were found to perform an increasing proportion of complex open aneurysm repairs, involving concomitant renal and visceral bypass procedures. On multivariate analysis, strong determinants of cost increase for both endovascular aortic aneurysm repair and open aortic aneurysm repair are rupture status, prolonged length of stay, occurrence of complications, and the need for disposition to a nursing facility or another acute care institution.

CONCLUSION

As the vascular community has shifted from an open repair of abdominal aortic aneurysm to an endovascular approach, a number of unforeseen clinical and economic effects were noted. We have characterized these ramifications to help guide further clinical decision and resource allocation.

Fenestrated repair improves perioperative outcomes but lacks a hospital volume association for complex abdominal aortic aneurysms

BACKGROUND

Complex abdominal aortic aneurysms (AAAs) have traditionally been treated with an open surgical repair (OSR). During the past decade, fenestrated endovascular aneurysm repair (FEVAR) has emerged as a viable option. Hospital procedural volume to outcome relationship for OSR of complex AAAs has been well established, but the impact of procedural volume on FEVAR outcomes remains undefined. This study investigated the outcomes of OSR and FEVAR for the treatment of complex AAAs and examined the hospital volume-outcome relationship for these procedures.

METHODS

A retrospective review of a statewide vascular surgery registry was queried for all patients between 2012 and 2018 who underwent elective repair of a juxtarenal/pararenal AAA with FEVAR or OSR. The primary outcomes were 30-day mortality, myocardial infarction, and new dialysis. Secondary end points included postoperative pneumonia, renal dysfunction (creatine concentration increase of >2 mg/dL from preoperative baseline), major bleeding, early procedural complications, length of stay, and need for reintervention. To evaluate procedural volume-outcomes relationship, hospitals were stratified into low- and high-volume aortic centers based on a FEVAR annual procedural volume. To account for baseline differences, we calculated propensity scores and employed inverse probability of treatment weighting in comparing outcomes between treatment groups.

RESULTS

A total of 589 patients underwent FEVAR (n = 186) or OSR (n = 403) for a complex AAA. After adjustment, OSR was associated with higher rates of 30-day mortality (10.7% vs 2.9%; P < .001) and need for dialysis (11.3% vs 1.8; P < .001). Postoperative pneumonia (6.8% vs 0.3%; P < .001) and need for transfusion (39.4% vs 10.4%; P < .001) were also significantly higher in the OSR cohort. The median length of stay for OSR and FEVAR was 9 days and 3 days, respectively. For those who underwent FEVAR, endoleaks were present in 12.1% of patients at 30 days and 6.1% of patients at 1 year, with the majority being type II. With a median follow-up period of 331 days (229-378 days), 1% of FEVAR patients required a secondary procedure, and there were no FEVAR conversions to an open aortic repair. Hospitals were divided into low- and high-volume aortic centers based on their annual FEVAR volume of complex AAAs. After adjustment, hospital FEVAR procedural volume was not associated with 30-day mortality or myocardial infarction.

CONCLUSIONS

FEVAR was associated with lower perioperative morbidity and mortality compared with OSR for the management of complex AAAs. Procedural FEVAR volume outcome analysis suggests limited differences in 30-day morbidity, although long-term durability warrants further research.

Intentional Clinical Process Design to Improve Outcomes for Patients Who Require Emergency Surgery

Ruptured abdominal aortic aneurysms (AAAs) are associated with a 90% overall mortality and $150 000 cost of care per patient. Despite improvements in intensive care and surgical technology, morbidity and mortality remain unchanged over the past 20 years. The most significant predictor of survival is time from the door of the hospital to the operating room. To streamline operational efficiency, a team utilized Lean Six Sigma methodologies, team training, and intentional clinical process design to institute changes in our clinical processes, enhance care coordination, and improve communication. Changes led to a $1.8 million profit on operations, 10-day reduction in length of stay, and 89% survival rate among patients with ruptured AAA.

Hospital volume and mortality after transjugular intrahepatic portosystemic shunt creation in the United States

The link between higher procedure volume and better outcomes for surgical procedures is well established. We aimed to determine whether procedure volume affected inpatient mortality in patients undergoing transjugular intrahepatic portosystemic shunt (TIPS). An epidemiological analysis of an all-payer database recording hospitalizations during 2013 in the United States (Nationwide Readmissions Database) was performed. All patients ≥ 18 years old undergoing TIPS during a hospital admission (n = 5529) without concurrent or prior liver transplantation were selected. All-cause inpatient mortality was assessed. Risk-adjusted mortality was assessed for hospitals categorized into quintiles based on annual TIPS volume (very low, 1-4/year; low, 5-9/year; medium, 10-19/year; high, 20-29/year; and very high, ≥ 30/year). TIPS were placed in all 5529 patients (mean age, 57 years [standard deviation, ± 10.9 years]; women, n = 2071; men, n = 3458). Mortality decreased with rising annual TIPS volume (13% for very low to 6% for very high volume hospitals; P < 0.01). Elective admissions were more common in hospitals with higher annual TIPS volume (20.3% for very low to 30.8% for very high; P < 0.01). On multivariate analysis, compared with hospitals performing ≥30 TIPS per year, only hospitals performing 1-4/year (adjusted odds ratio [aOR], 1.9; 95% confidence interval [CI], 1.21-3.01; P = 0.01), 5-9/year (aOR, 2.0; 95% CI, 1.25-3.17; P < 0.01), and 10-19/year (aOR, 1.9; 95% CI, 1.17-3.00; P = 0.01) had higher inpatient mortality (20-29/year: aOR, 1.4; 95% CI, 0.84-2.84; P = 0.19). The absolute difference between risk-adjusted mortality rate for very low volume and very high volume hospitals was 6.1% (13.9% versus 7.8%). TIPS volume of ≤ 20 TIPS/year, variceal bleeding, and nosocomial infections were independent risk factors for inpatient mortality in patients with both elective and emergent admissions. Conclusion: The risk of inpatient mortality is lower in hospitals performing ≥20 TIPS per year. Future research exploring preventable factors for higher mortality and benefits of patient transfer to higher volume centers is warranted. (Hepatology 2018;67:690-699).

[Patient volume and quality in surgery for abdominal aortic aneurysm]

BACKGROUND Patient volume is assumed to affect quality, whereby complex procedures are best performed by those who perform them frequently. We have conducted a systematic review of the research on the association between patient volume and quality of vascular surgery. In this article we describe the outcomes for abdominal aortic aneurysm surgery.MATERIAL AND METHOD We undertook systematic searches in relevant databases. We searched for systematic reviews, and randomised and observational studies. The search was concluded in December 2015. We have summarised the results descriptively and assessed the overall quality of the evidence.RESULTS Forty-six observational studies fulfilled our inclusion criteria. We found a possible association for both hospital and surgeon volume. Higher patient volume may possibly be associated with lower 30-day mortality and lower hospital mortality for both open and endovascular surgery. Although the association appears to apply to both elective and acute hospitalisations, there is greater uncertainty with regard to the most ill patients. For hospital volume there may also be fewer complications for open and endovascular surgery, as well as for all surgery assessed as a whole. We considered the evidence base to be medium to very low quality.INTERPRETATION We found a possible correlation between patient volume and quality indicators such as mortality and complications. It may be advantageous to allocate planned procedures to institutions and surgeons with high volume, while this is less certain with regard to acute hospitalisations.

Adjusted Hospital Outcomes of Abdominal Aortic Aneurysm Surgery Reported in the Dutch Surgical Aneurysm Audit

OBJECTIVE/BACKGROUND

The Dutch Surgical Aneurysm Audit (DSAA) is mandatory for all patients with primary abdominal aortic aneurysms (AAAs) in the Netherlands. The aims are to present the observed outcomes of AAA surgery against the predicted outcomes by means of V-POSSUM (Vascular-Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity). Adjusted mortality was calculated by the original and re-estimated V(physiology)-POSSUM for hospital comparisons.

METHODS

All patients operated on from January 2013 to December 2014 were included for analysis. Calibration and discrimination of V-POSSUM and V(p)-POSSUM was analysed. Mortality was benchmarked by means of the original V(p)-POSSUM formula and risk-adjusted by the re-estimated V(p)-POSSUM on the DSAA.

RESULTS

In total, 5898 patients were included for analysis: 4579 with elective AAA (EAAA) and 1319 with acute abdominal aortic aneurysm (AAAA), acute symptomatic (SAAA; n = 371) or ruptured (RAAA; n = 948). The percentage of endovascular aneurysm repair (EVAR) varied between hospitals but showed no relation to hospital volume (EAAA: p = .12; AAAA: p = .07). EAAA, SAAA, and RAAA mortality was, respectively, 1.9%, 7.5%, and 28.7%. Elective mortality was 0.9% after EVAR and 5.0% after open surgical repair versus 15.6% and 27.4%, respectively, after AAAA. V-POSSUM overestimated mortality in most EAAA risk groups (p < .01). The discriminative ability of V-POSSUM in EAAA was moderate (C-statistic: .719) and poor for V(p)-POSSUM (C-statistic: .665). V-POSSUM in AAAA repair overestimated in high risk groups, and underestimated in low risk groups (p < .01). The discriminative ability in AAAA of V-POSSUM was moderate (.713) and of V(p)-POSSUM poor (.688). Risk adjustment by the re-estimated V(p)-POSSUM did not have any effect on hospital variation in EAAA but did in AAAA.

CONCLUSION

Mortality in the DSAA was in line with the literature but is not discriminative for hospital comparisons in EAAA. Adjusting for V(p)-POSSUM, revealed no association between hospital volume and treatment or outcome. Risk adjustment for case mix by V(p)-POSSUM in patients with AAAA has been shown to be important.

Emergent Endovascular Stent Grafts for Ruptured Aortic Aneurysms

Ruptured aortic aneurysms uniformly require emergent attention. Historically, urgent surgical repair or medical management was the only treatment options. The development of covered stent grafts has introduced a third approach in the care of these critical patients. The clinical status of the patient and local physician expertise drive the treatment modalities in the majority of cases. The goal of therapy in these patients is to stabilize the patient as quickly as possible, establish maximum survival with minimum morbidity, and provide a long lasting result. The endovascular approach has become an acceptable treatment option in an increasing number of patients presenting with ruptured aneurysmal disease of both the descending thoracic and abdominal aorta. Major factors influencing treatment include patient clinical status, characteristics of the aorta, physician preference, institutional experience, and availability of appropriate equipment. Planning, experience, and the ability to improvise effective solutions are keys to the success of the procedure when endovascular techniques are utilized. Three separate cases, requiring intraprocedural improvisation, are presented followed by a review of the literature.