Patients with a Ruptured Abdominal Aortic Aneurysm Are Better Informed in Hospitals with an "EVAR-preferred" Strategy: An Instrumental Variable Analysis of the Dutch Surgical Aneurysm Audit.

BACKGROUND: While several observational studies suggested a lower postoperative mortality after minimal invasive endovascular aneurysm repair (EVAR) in patients with a ruptured abdominal aortic aneurysm (RAAA) compared to conventional open surgical repair (OSR), landmark randomized controlled trials have not been able to prove the superiority of EVAR over OSR. Randomized controlled trials contain a selected, homogeneous population, influencing external validity. Observational studies are biased and adjustment of confounders can be incomplete. Instrumental variable (IV) analysis (pseudorandomization) may help to answer the question if patients with an RAAA have lower postoperative mortality when undergoing EVAR compared to OSR. METHODS: This is an observational study including all patients with an RAAA, registered in the Dutch Surgical Aneurysm Audit between 2013 and 2017. The risk difference (RD) in postoperative mortality (30 days/in-hospital) between patients undergoing EVAR and OSR was estimated, in which adjustment for confounding was performed in 3 ways: linear model adjusted for observed confounders, propensity score model (multivariable logistic regression analysis), and IV analysis (two-stage least square regression), adjusting for observed and unobserved confounders, with the variation in percentage of EVAR per hospital as the IV instrument. RESULTS: 2419 patients with an RAAA (1489 OSR and 930 EVAR) were included. Unadjusted postoperative mortality was 34.9% after OSR and 22.6% after EVAR (RD 12.3%, 95% CI 8.5-16%). The RD adjusted for observed confounders using linear regression analysis and propensity score analysis was, respectively, 12.3% (95% CI 9.6-16.7%) and 13.2% (95%CI 9.3-17.1%) in favor of EVAR. Using IV analysis, adjusting for observed and unobserved confounders, RD was 8.9% (95% CI -1.1-18.9%) in favor of EVAR. CONCLUSIONS: Adjusting for observed confounders, patients with an RAAA undergoing EVAR had a significant better survival than OSR in a consecutive large cohort. Adjustment for unobserved confounders resulted in a clinical relevant RD. An "EVAR preference strategy" in patients with an RAAA could result in lower postoperative mortality.

Toward Optimizing Risk Adjustment in the Dutch Surgical Aneurysm Audit.

BACKGROUND: To compare hospital outcomes of aortic aneurysm surgery, casemix correction for preoperative variables is essential. Most of these variables can be deduced from mortality risk prediction models. Our aim was to identify the optimal set of preoperative variables associated with mortality to establish a relevant and efficient casemix model. METHODS: All patients prospectively registered between 2013 and 2016 in the Dutch Surgical Aneurysm Audit (DSAA) were included for the analysis. After multiple imputation for missing variables, predictors for mortality following univariable logistic regression were analyzed in a manual backward multivariable logistic regression model and compared with three standard mortality risk prediction models: Glasgow Aneurysm Score (GAS, mainly clinical parameters), Vascular Biochemical and Haematological Outcome Model (VBHOM, mainly laboratory parameters), and Dutch Aneurysm Score (DAS, both clinical and laboratory parameters). Discrimination and calibration were tested and considered good with a C-statistic > 0.8 and Hosmer-Lemeshow (H-L) P > 0.05. RESULTS: There were 12,401 patients: 9,537 (76.9%) elective patients (EAAA), 913 (7.4%) acute symptomatic patients (SAAA), and 1,951 (15.7%) patients with acute rupture (RAAA). Overall postoperative mortality was 6.5%; 1.8% after EAAA surgery, 6.6% after SAAA, and 29.6% after RAAA surgery. The optimal set of independent variables associated with mortality was a mix of clinical and laboratory parameters: gender, age, pulmonary comorbidity, operative setting, creatinine, aneurysm size, hemoglobin, Glasgow coma scale, electrocardiography, and systolic blood pressure (C-statistic 0.871). External validation overall of VBHOM, DAS, and GAS revealed C-statistics of 0.836, 0.782, and 0.761, with an H-L of 0.028, 0.00, and 0.128, respectively. CONCLUSIONS: The optimal set of variables for casemix correction in the DSAA comprises both clinical and laboratory parameters, which can be collected easily from electronic patient files and will lead to an efficient casemix model.

Failure to Rescue - a Closer Look at Mortality Rates Has No Added Value for Hospital Comparisons but Is Useful for Team Quality Assessment in Abdominal Aortic Aneurysm Surgery in The Netherlands.

OBJECTIVES: Failure to rescue (FTR) is a composite quality indicator, defined as the proportion of deceased patients following major complications. The aims of this study were to compare FTR with mortality for hospital comparisons in abdominal aortic aneurysm (AAA) surgery in The Netherlands and investigate hospital volume and associated factors. METHODS: Patients prospectively registered between 2013 and 2015 in the Dutch Surgical Aneurysm Audit (DSAA) were analysed. FTR was analysed for AAA patients and subgroups elective (EAAA) and acute (AAAA; symptomatic or ruptured) aneurysms. Variables and hospital volume were analysed by uni- and multivariable regression analysis. Adjusted hospital comparisons for mortality, major complications, and FTR were presented in funnel plots. Isomortality lines were constructed when presenting FTR and major complication rates. RESULTS: A total of 9258 patients were analysed in 61 hospitals: 7149 EAAA patients (77.2%) and 2109 AAAA patients (22.8%). There were 2785 (30.1%) patients with complications (unadjusted range 5-65% per hospital): 2161 (77.6%) with major and 624 (28.4%) patients with minor complications. Overall mortality was 6.6% (adjusted range 0-16% per hospital) and FTR was 28.4% (n = 613) (adjusted range 0-60% per hospital). Glasgow Coma Scale, age, pulse, creatinine, electrocardiography, and operative setting were independently associated with FTR. Hospital volume was not associated with FTR. In AAAA patients hospital volume was significantly associated with a lower adjusted major complication and mortality rate (OR 0.62, 95% CI 0.49-0.78; and 0.64, 95% CI 0.48-0.87). Four hospitals had a significant lower adjusted FTR with different major complication rates on different isomortality lines. CONCLUSIONS: There was more variation in FTR than in mortality between hospitals. FTR identified the same best performing hospitals as for mortality and therefore was of limited additional value in measuring quality of care for AAA surgery. FTR can be used for internal quality improvement with major complications in funnel plots and diagrams with isomortality lines.

Obesity as a determinant of perioperative and postoperative outcome in patients following colorectal cancer surgery: A population-based study (2009-2016).

BACKGROUND: Obesity is an increasing problem worldwide that can influence perioperative and postoperative outcomes. However, the relationship between obesity and treatment-related perioperative and short-term postoperative morbidity after colorectal resections is still subject to debate. STUDY: Patients were selected from the DCRA, a population-based audit including 83 hospitals performing colorectal cancer (CRC) surgery. Data regarding primary resections between 2009 and 2016 were eligible for analyses. Patients were subdivided into six categories: underweight, normal weight, overweight and obesity class I, II and III. RESULTS: Of 71,084 patients, 17.7% with colon and 16.4% with rectal cancer were categorized as obese. Significant differences were found for the 30-day overall postoperative complication rate (p < 0.001), prolonged hospitalization (p < 0.001) and readmission rate (colon cancer p < 0.005; rectal cancer p < 0.002) in obese CRC patients. Multivariate analysis identified BMI ≥30 kg/m2 as independent predictor of a complicated postoperative course in CRC patients. Furthermore, obesity-related comorbidities were associated with higher postoperative morbidity, prolonged hospitalization and a higher readmission rate. No significant differences in performance were observed in postoperative outcomes of morbidly obese CRC patients between hospitals performing bariatric surgery and hospitals that did not. CONCLUSION: The real-life data analysed in this study reflect daily practice in the Netherlands and identify obesity as a significant risk factor in CRC patients. Obesity-related comorbidities were associated with higher postoperative morbidity, prolonged hospitalization and a higher readmission rate in obese CRC patients. No differences were observed between hospitals performing bariatric surgery and hospitals that did not.

A registry-based rationale for discrete intervention thresholds for open and endovascular elective abdominal aortic aneurysm repair in female patients.

OBJECTIVE: An evidence-based consensus for a female-specific intervention threshold for abdominal aortic aneurysms (AAAs) is missing. This study aims to analyze sex-related differences in the epidemiology of ruptured AAA to establish an intervention threshold for women. METHODS: The Dutch Surgical Aneurysm Audit (DSAA) is a compulsory, nation-wide registry of AAA repairs in The Netherlands. All patients with emergency or elective AAA repair between January 1, 2013, and December 31, 2015, were included in the analysis. The main outcomes were age, sex, AAA diameter at time of rupture, and 30-day postoperative mortality. RESULTS: A total of 1561 ruptured AAA repairs (14.7% women) and 7063 cases of elective AAA repair (13.7% women) were included in the analysis. Women had significantly smaller mean ± standard deviation AAA diameter at time of rupture than men; 70.5 ± 14.4 mm and 78.6 ± 17.5 mm, respectively. In male patients, 8% of ruptures occurred at diameters below the 55 mm intervention threshold. The female equivalent of this eighth percentile is 52 mm. Female patients had significantly higher 30-day mortality after emergency repair, namely, 33% for women versus 24.2% for men, but were also significantly older, mean ± standard deviation age 76.7 ± 7.1 years and 73.9 ± 8.3 years for women and men, respectively. Correcting for age reduced the 30-day mortality risk for women after ruptured AAA repair from 1.53 (95% confidence interval, 1.14-2.04) to 1.27 (95% confidence interval, 0.92-1.73). Outcome after open elective repair was significantly worse for women compared with men, with a 30-day mortality of 7.97% 30 for women and 4.27% for men (P < .01). CONCLUSIONS: The equivalent of the 55-mm intervention threshold for elective endovascular AAA repair in men is 52 mm in women. The almost doubled mortality risk for elective open repair in women implies that the optimal point for open repair is at higher diameters, very possibly at least 55 mm.

Textbook Outcome: A Composite Measure for Quality of Elective Aneurysm Surgery.

OBJECTIVE: To investigate a new composite quality measurement, which comprises a desirable outcome for elective aneurysm surgery, called "Textbook Outcome" (TO). BACKGROUND: Single-quality indicators in vascular surgery are often not distinctive and insufficiently reflect the quality of care. METHODS: All patients undergoing elective abdominal aortic aneurysm repair, registered in the Dutch Surgical Aneurysm Audit between 2014 and 2015 were included. TO was defined as the percentage of patients who had abdominal aortic aneurysm-repair without intraoperative complications, postoperative surgical complications, reinterventions, prolonged hospital stay [endovascular aneurysm repair (EVAR) ≤4 d, open surgical repair (OSR) ≤10 d], readmissions, and postoperative mortality (≤30 d after surgery/at discharge). Case-mix adjusted TO rates were used to compare hospitals and to compare individual hospital results for different procedures. RESULTS: Five thousand one hundred seventy patients were included, of whom 4039 were treated with EVAR and 1131 with OSR. TO was achieved in 71% of EVAR and 53% of OSR. Important obstacles for achieving TO were a prolonged hospital stay, postoperative complications, and readmissions. Adjusted TO rates varied from 38% to 89% (EVAR) and from 0% to 97% (OSR) between individual hospitals. Hospitals with a high TO for OSR also had a high TO for EVAR; however, a high TO for EVAR did not implicate a high TO for OSR. CONCLUSIONS: TO generates additional information to evaluate the overall quality of the care of elective aneurysm surgery, which subsequently can be used by hospitals to improve the quality of their care.

Colorectal cancer surgery for obese patients: Financial and clinical outcomes of a Dutch population-based registry.

BACKGROUND AND OBJECTIVES: The objective of this study was to explore the association among adverse events, body mass index (BMI), and hospital costs after colorectal cancer surgery in a country with an intermediate BMI distribution. METHODS: All colorectal cancer procedures in 29 Dutch hospitals listed in a 2010-2012 population-based database and with a BMI > 18.5 were included (n = 8687). Hospital costs were measured uniformly and based on time-driven activity-based costing. The BMI classification of the World Health Organization was used. RESULTS: Patients in obesity classes 1 (23.6% [after risk-adjustment OR 1.245, CI 1.064-1.479, P = 0.007]) and ≥2 (28.1% [after risk-adjustment OR 1.816, CI 1.382-2.388, P < 0.001]) were associated with more severe complications and higher hospital costs (€14,294, +9.6%, after risk-adjustment +7.9%, P < 0.001; and €15,913 +22.0%, after risk-adjustment +21.2%, P < 0.001, respectively) than normal weight patients (20.8% and €13,040, respectively). Pre-obese patients had significantly lower mortality rates (2.7%, after risk-adjustment, OR 0.756, CI 0.577-0.991, P = 0.042) than normal-weight patients (3.9%). CONCLUSIONS: Obese surgical colorectal cancer patients in a country with an intermediate BMI distribution are associated with a significant increase in hospital costs because these patients suffer from more severe complications. This is the first study to provide evidence for the "obesity-paradox" for mortality in colorectal cancer surgery. J. Surg. Oncol. 2016;113:489-495. © 2016 Wiley Periodicals, Inc.

Median nerve neuropraxia by a large false brachial artery aneurysm.

Peripheral nerve compression is a rare complication of an iatrogenic false brachial artery aneurysm. We present a 72-year-old patient with median nerve compression due to a false brachial artery aneurysm after removal of an arterial catheter. Surgical exclusion of the false aneurysm was performed in order to release traction of the median nerve. At 3-month assessment, moderate hand recovery in function and sensibility was noted. In the case of neuropraxia of the upper extremity, following a history of hospital stay and arterial lining or catheterization, compression due to pseudoaneurysm should be considered a probable cause directly at presentation. Early recognition and treatment is essential to avoid permanent neurological deficit.