Lasagna plots to visualize results in surgical studies

A lasagna plot is a graphical tool that can display multiple longitudinal outcomes. To our knowledge, lasagna plots have not been used in publications of surgical studies before. The objective of this study was to demonstrate the results of surgical randomized controlled trials (RCTs) with lasagna plots in order to assess whether this can lead to new observations of the data presented in the original studies. Lasagna plots were created with R for an RCT comparing endovascular and open repair for patients with a ruptured abdominal aortic aneurysm (AJAX trial), an RCT comparing laparoscopy or open surgery combined with either fast track or standard care for patients with colon cancer (LAFA trial) and an RCT comparing preoperative biliary drainage and early surgery for patients with pancreatic cancer (DROP trial). Regarding the AJAX trial, the original article had reported the rate of outcomes at 30 days after repair in two tables. The plots additionally demonstrated the moments of occurrence, increase and decrease of multiple outcomes such as renal replacement therapy and occurrence of death within one plot. These observations were not presented in the original article. The lasagna plots of the LAFA and DROP trial revealed similar new observations on multiple longitudinal outcomes. By revealing new observations of the previously published data, lasagna plots generate new hypotheses and theories regarding the outcomes. As such, lasagna plots may be a useful addition to traditional tables and figures and could improve the interpretation of result

External validation of the Endovascular aneurysm repair Risk Assessment model in predicting survival, reinterventions, and endoleaks after endovascular aneurysm repair

The Endovascular aneurysm repair Risk Assessment (ERA) model predicts survival (early death, 3-year survival, and 5-year survival), reinterventions, and endoleaks after elective endovascular aneurysm repair. We externally validated the ERA model in our cohort of patients. This was a retrospective validation study of 433 consecutive patients with an asymptomatic abdominal aortic aneurysm treated with endovascular aneurysm repair in three hospitals (Amsterdam, The Netherlands) between 1997 and 2010. The area under the receiver operating characteristic curve was used as measure of accuracy (>0.70 was considered as sufficiently accurate). The early death rate was 1% (3 of 433; 95% confidence interval [CI], 0%-2%), the 5-year survival rate was 65% (95% CI, 61%-70%), the 5-year reintervention rate was 18% (95% CI, 14-78%), and the 5-year rate of type I, II, or III endoleak was 25% (95% CI, 20%-29%). The areas under the curve varied between 0.64 and 0.66 for predictions of survival and between 0.47 and 0.61 for reinterventions and endoleaks. The predictions of survival, reinterventions, and endoleaks made by the ERA model were not sufficiently accurate to be used in our clinical practic

Long-term survival after acute kidney injury following ruptured abdominal aortic aneurysm repair

Objective: Acute kidney injury (AKI) is a major complication of ruptured abdominal aortic aneurysm (RAAA). Severe AKI is associated with high morbidity and mortality in the short term. The objective of this study was to determine the association between AKI after RAAA repair and long-term survival. Methods: We conducted a retrospective cohort study of all patients undergoing RAAA repair in three hospitals between 2004 and 2011. Outcomes were long-term survival after RAAA repair, incidence of postoperative AKI, and chronic dialysis rates. Survival rates were compared between different AKI groups (no AKI, Risk, Injury, Failure) with Kaplan-Meier survival analyses and log-rank tests. Univariable and multivariable Cox regression analyses were carried out to assess the association of survival with AKI, preoperative shock, postoperative shock, and sex. The main analysis focused on the group of patients surviving initial hospital stay. Results: Our study encompassed 362 patients with RAAA. AKI occurred in 267 of 362 patients (74%). At discharge, 267 patients were alive (74%). Median survival in this group was 7.2 years. Survival was not significantly different between the four AKI groups (P = .07). However, the univariable Cox regression analysis demonstrated a significant association between Failure and reduced long-term survival compared with having no AKI (hazard ratio, 1.85; 95% confidence interval, 1.15-2.97). This association did not remain significant after multivariable adjustment. Four patients were discharged with chronic dialysis, and four other patients needed chronic dialysis later after discharge. Conclusions: This study demonstrates no significant independent association between AKI after RAAA repair and long-term survival. Only a small proportion of patients developed end-stage renal disease at a later stage in life

Long-term survival after acute kidney injury following ruptured abdominal aortic aneurysm repair

Acute kidney injury (AKI) is a major complication of ruptured abdominal aortic aneurysm (RAAA). Severe AKI is associated with high morbidity and mortality in the short term. The objective of this study was to determine the association between AKI after RAAA repair and long-term survival. We conducted a retrospective cohort study of all patients undergoing RAAA repair in three hospitals between 2004 and 2011. Outcomes were long-term survival after RAAA repair, incidence of postoperative AKI, and chronic dialysis rates. Survival rates were compared between different AKI groups (no AKI, Risk, Injury, Failure) with Kaplan-Meier survival analyses and log-rank tests. Univariable and multivariable Cox regression analyses were carried out to assess the association of survival with AKI, preoperative shock, postoperative shock, and sex. The main analysis focused on the group of patients surviving initial hospital stay. Our study encompassed 362 patients with RAAA. AKI occurred in 267 of 362 patients (74%). At discharge, 267 patients were alive (74%). Median survival in this group was 7.2 years. Survival was not significantly different between the four AKI groups (P = .07). However, the univariable Cox regression analysis demonstrated a significant association between Failure and reduced long-term survival compared with having no AKI (hazard ratio, 1.85; 95% confidence interval, 1.15-2.97). This association did not remain significant after multivariable adjustment. Four patients were discharged with chronic dialysis, and four other patients needed chronic dialysis later after discharge. This study demonstrates no significant independent association between AKI after RAAA repair and long-term survival. Only a small proportion of patients developed end-stage renal disease at a later stage in lif

The Value of Sigmoidoscopy to Detect Colonic Ischaemia After Ruptured Abdominal Aortic Aneurysm Repair

Objectives: Diagnosing colonic ischaemia (CI) after ruptured abdominal aortic aneurysm (RAAA) repair is challenging. This study determined the diagnostic value of sigmoidoscopy in patients suspected of CI after RAAA repair. Methods: This was a retrospective multicentre cohort study. Patients who underwent RAAA repair in three hospitals in Amsterdam, the Netherlands, between 2004 and 2011 (AJAX cohort) were included. Sigmoidoscopies were carried out based on clinical judgment. Endoscopy results were classified as “no ischaemia,” “mild CI,” or “moderate to severe CI.” The surgical diagnosis was classified as “transmural” or “no transmural” CI. The value of sigmoidoscopy was assessed with calculation of positive and negative predictive values (PPV, NPV) with 95% CI for transmural CI. Logistic regression analysis was used to express the association of risk factors with CI as adjusted OR. Results: Transmural CI was diagnosed in 23 of 351 patients (6.6%). Thirteen of sixteen patients (81%) who underwent direct laparotomy for high suspicion of CI indeed had transmural CI. Forty-six patients (13%) underwent sigmoidoscopy. The prevalence of transmural CI was 22% (10/46; 95% CI 12–36%) in these patients. The PPV for transmural CI of “moderate to severe CI” on sigmoidoscopy was 73% (8/11; 95% CI 43–90%). The PPV of “mild CI” on sigmoidoscopy was 11% (2/19; 95% CI 2.9–31%). The NPV of “no ischaemia” on sigmoidoscopy was 100% (95% CI 78–100%). Cardiac comorbidity (OR 3.1, 95% CI 1.19–7.97), low first haemoglobin (OR 0.6, 95% CI 0.47–0.87), and high vasopressor administration (OR 9.4, 95% CI 1.99–44.46) were independently associated with CI. Conclusions: Sigmoidoscopy increases the likelihood of correctly identifying the presence or absence of transmural CI, especially in patients with a moderate clinical suspicion for CI after RAAA repair

Validation of three models predicting in-hospital death in patients with an abdominal aortic aneurysm eligible for both endovascular and open repair

Objective: The Medicare, the Vascular Governance North West (VGNW), and the British Aneurysm Repair (BAR) models can be used to predict in-hospital death after an intervention for an asymptomatic abdominal aortic aneurysm (AAA). Validation of these models in patients with suitable aortic anatomy for endovascular repair and a general condition fit for open repair is lacking. We validated the Medicare, VGNW, and BAR models in patients from a randomized controlled trial comparing open and endovascular AAA repair. Methods: A per-protocol analysis was done of 345 Dutch and Belgian patients with in-hospital death as the primary end point. The prediction models were validated taking into account discrimination (the ability to distinguish between death and survival) and calibration (the agreement between predicted and observed death rates). Discrimination was assessed using the area under the receiver-operating characteristics curve (AUC). An AUC >0.70 was considered to be sufficiently accurate. Calibration was assessed using the Hosmer-Lemeshow (HL) test, and P > .05 was considered to be sufficiently accurate. Results: The AUC was 0.77 (95% confidence interval [CI], 0.64-0.90; HL test, P = .52) for the Medicare model, 0.88 (95% CI, 0.81-0.95; HL test, P = .31) for the VGNW model, and 0.79 (95% CI, 0.67-0.91; HL test, P = .15) for the BAR model. Conclusions: In AAA patients eligible for endovascular and open repair, the predictions of in-hospital death by the Medicare, VGNW, and BAR models were sufficiently accurate. Therefore, these models can be used to support deciding between endovascular and open repair

Survival outcomes of patients with muscle-invasive bladder cancer according to pathological response at radical cystectomy with or without neo-adjuvant chemotherapy: a case-control matching study

Objectives To assess survival of patients with muscle-invasive bladder cancer (MIBC) who underwent radical cystectomy (RC) with or without neo-adjuvant chemotherapy (NAC) according to the pathological response at RC. Methods 965 patients with MIBC (cT2-4aN0M0) who underwent RC with or without NAC were analyzed. Among the collected data were comorbidity, clinical and pathological tumor stage, tumor grade, nodal status (y)pN, and OS. Case–control matching of 412 patients was performed to compare oncological outcomes. Kaplan–Meier curves were created to estimate OS for patients who underwent RC with or without NAC, and for those with complete response (pCR), partial response (pPR), or residual or progressive disease (PD). Results Patients with a pCR or pPR at RC, with or without NAC, had better OS than patients who had PD (both p val- ues < 0.001). Moreover, the incidence of pCR was significantly higher in patients receiving NAC prior to RC than in patients undergoing RC only (31% versus 15%, respectively; p < 0.001). Case–control matching displayed better OS of patients who underwent RC with NAC, median survival not reached, than of those who underwent RC only, median 4.5 years (p = 0.023). Conclusions This study showed that patients with MIBC who underwent NAC with RC had a significant better OS than those who underwent RC only. The proportion of patients with a pCR was higher in those who received NAC and RC than in those who were treated by RC only. The favorable OS rate in the NAC and RC cohort was probably attributed to the higher observed pCR rate