Current determinants of operative mortality in 1400 patients requiring aortic valve replacement

BACKGROUND: Determinants of operative mortality after aortic valve replacement vary with a changing patient population due to advances in operative management and increasing life expectancy. In order to predict current groups of high risk patients, a statistically valid large study population base recruited over a short period of time is required. METHODS: Between January 1996 and June 2001, 1408 aortic valves were replaced in 1400 patients (572 of them with simultaneous coronary artery bypass grafting). The data were analyzed by multivariate logistic regression to evaluate the operative risk. Mean age of the study population was 68 +/- 11 years (range 19 to 90 years old, 44% female). RESULTS: Overall operative mortality (within 30 days) was 3.8%. Independent predictive factors for operative mortality were previous bypass surgery, emergency operation, simultaneous mitral valve replacement, renal dysfunction, more than 80 years old, simultaneous bypass surgery in female patients with a body mass index greater than 29 kg/m(2), and height smaller than 1.57 m for patients more than 71 years old. Simultaneous coronary artery bypass grafting in general (p = 0.6), previous aortic valve replacement (p = 0.59), and implantation of stented bioprostheses (p = 0.39) or stentless bioprostheses (p = 0.7) were not identified as independent risk factors. CONCLUSIONS: Certain groups of patients with a high operative risk were identified: patients more than 80 years old, women with a body mass index greater 29 kg/m(2) undergoing simultaneous coronary artery bypass surgery, and "small" patients more than 71 years old.     

Impact of complications on outcomes following aortic and mitral valve replacements in the United States

AIM: Heart valve replacement surgeries account for 20% of all cardiac procedures. In-hospital mortality rates are approximately 6% for aortic valve replacements and 10% for mitral valve replacements. The objectives of the study are to provide nationally representative estimates of complications following aortic and mitral valve replacements and to quantify the impact of different types of complications on in-hospital outcomes. METHODS: The Nationwide Inpatient Sample was analyzed for years 2000-2003. The effect of complications on in-hospital mortality, length of stay (LOS), and hospital charges were examined using bivariate and multivariable logistic and linear regression analyses. The confounding effects of age, sex, primary diagnosis, type of valve replacement, type of admission, comorbid conditions, and hospital characteristics were adjusted. RESULTS: A total of 43,909 patients underwent aortic valve replacement as the primary procedure during the study period and 16,516 patients underwent mitral valve replacement. Complications occurred in 35.2% of those undergoing aortic valve replacements and in 36.4% of those undergoing mitral valve replacements. Almost half of these are cardiac complications and a quarter involve hemorrhage/hematoma/seroma. Complications were significantly associated with in-hospital mortality, LOS, and hospital charges even after adjusting for patient and hospital characteristics. CONCLUSION: Complications are prevalent and exert a considerable influence on outcomes following aortic and mitral valve replacements. Quality initiatives should focus on minimizing complications and improving processes of care that would enable complications to be better resolved if they occur.     

Impact of a blood conservation program on 30-day morbidity and mortality: a cohort study

Background

There are little published data on outcomes of blood conservation (BC) patients after noncardiac surgery. The objective of this study was to compare the surgical outcomes of patients enrolled in our BC program with that of the general population of surgical patients.

Methods

BC patients at our institution undergoing various surgical procedures were identified from the 2007–2009 National Surgical Quality Improvement Program database and compared with a cohort of conventional care (CC) patients matched by age, gender, and surgical procedure. Univariate and multiple logistic regression analyses were performed to evaluate 30-d postoperative outcomes.

Results

One hundred twenty BC patients were compared with 238 CC patients. The two groups were similar for all preoperative variables except smoking, which was lower in the BC group. On univariate analysis, BC patients had similar mean operating time (148 versus 155 min; P = 0.5), length of stay (5.9 versus 5.5 d; P = 0.7), and rate of return to the operating room (7.5% versus 5.5%; P = 0.4) compared with CC patients. BC and CC patients had similar 30-d morbidity (18% versus 14%; P = 0.3) and mortality rates (1.6% versus 1.3%; P = 1.0), respectively. On multivariable analysis, enrollment in the BC program had no impact on postoperative 30-d morbidity (odds ratio, 1.78; 95% confidence interval, 0.71–4.47) or 30-d mortality (unadjusted odds ratio, 1.33; 95% confidence interval, 0.22–8.05).

Conclusions

Short-term postoperative outcomes in BC patients are similar to the general population, and these patients should not be denied surgical treatment based on their unwillingness to receive blood products.     

The 30-day mortality of ruptured abdominal aortic aneurysms: influence of gender, age, diameter and comorbidities

AIM: The aim of this study was to determine the influence of gender, age, the aneurysm diameter and comorbidity on the 30-day mortality after open repair of ruptured abdominal aortic aneurysms (AAA). METHODS: Between January 1, 1993, and December 31, 2006 all consecutive patients who underwent open repair for a ruptured AAA at the tertiary care of Catharina teaching Hospital were included in this study (N=186). Patients who underwent endovascular repair of their ruptured abdominal aortic aneurysms were excluded from this study. Patient and procedure characteristics were collected and analyzed in relation to 30-day mortality. The association between age, gender, diameter of AAA and comorbidity with 30-day mortality was analyzed with c2 are and logistic regression; a P value <0.05 was considered significant. RESULTS: In this study there were 186 patients with ruptured AAA repair with an 30-day mortality of 36.6% (68/186). Among female patient 30-day mortality was 45.8% (11/24) compared with 35.2% (57/162) among male patients (P=0.31). Patients of 80 years and older had a 61.3% (19/31) 30-day mortality where younger patients had 33% (51/155) 30-day mortality (P=0.02). Thirty-day mortality was 47.2% (17/36) for patients with an AAA less than 65 mm compared with 34% (36/104) for patients with an AAA of 65 mm or larger (P=0.16). Multivariate analysis demonstrated age was a significant predictor of ruptured AAA repair mortality (P=0.017). CONCLUSION: In this study, age was the only significant risk factor of 30-day mortality after open repair in patients with ruptured AAA.     

Variation and changes in state-specific carotid endarterectomy and 30-day mortality rates, United States, 1991-2000

OBJECTIVES: The objectives of this study were to investigate variations between states and changes in state-specific carotid endarterectomy (CEA) and 30-day mortality rates. Cross-sectional variations and changes over time in such measures may be indicative of improvement in the quality of care. METHODS: We performed retrospective analyses of pre-existing administrative data on Medicare beneficiaries aged 65 years and older in the United States. Age-adjusted, state-specific CEA rates and 30-day postoperative mortality rates in 1991, 1995 and 2000 were examined, as well as changes in these rates from 1991 to 1995 and from 1995 to 2000. Stroke mortality in the general population of each state was used as a crude measure of the need for CEA procedure in the state. The Spearman rank correlation analysis was used to study correlations between rates. Oldham's method was used to avoid the effect of regression to the mean. RESULTS: There were wide variations in the state-specific CEA rates, 30-day mortality, and in changes in these rates over time. The states with relatively low procedure rates in 1991 also had low rates in 1995 and 2000, and relatively higher increases in the rates. The states with relatively high 30-day mortality in 1991 or 1995 had lower increases or greater decreases in the rate. CEA rates were not correlated with any measure of surgical mortality, but they were correlated with stroke mortality in the general population. CONCLUSIONS: The inter-state variation in CEA rates has not changed much since 1991, but variation in 30-day mortality decreased through 2000. The states with low procedure rates in 1991 did not have sufficient increase to catch up with the high-rate states by 1995, but they were prone to experience a higher increase in the subsequent 5 years. The validity of stroke mortality in a state as a measure of the need for CEA is questionable. Further research using clinical data is needed to better explain variations between states.     

Trends of 30-day mortality and morbidities in endovascular repair of intact abdominal aortic aneurysm during the last decade

Objective

Significant research efforts have been made to improve the safety and efficacy of endovascular aneurysm repair (EVAR) in treating abdominal aortic aneurysm. This study aimed to examine the trends of perioperative outcomes of EVAR in the recent decade using a national validated database.

Aortic valve replacement in severe aortic stenosis with left ventricular dysfunction: determinants of cardiac mortality and ventricular function recovery

Objective: The influence of left ventricular (LV) dysfunction on survival of patients with severe aortic stenosis is poorly characterized. Few data are available about preoperative predictors of cardiac mortality and LV function recovery after aortic valve replacement of such patients. The aim of our study was to examine the outcome and the preoperative predictors of postoperative cardiac death and of LV function recovery in these patients. Methods: We evaluated 85 consecutive patients with severe aortic stenosis (aortic valve area <1 cm²) and severe depression of LV ejection fraction (EF) <35% at cardiac catheterization. Among them, 52 underwent aortic valve replacement and they were compared to patients who were not operated on. All patients had a mean clinical follow-up of 53 months and 94% of them had a mean echocardiographic follow-up of 14 months after aortic valve replacement. Results: The mean baseline characteristics included: LVEF 28±6%, peak-to-peak transvalvular gradient 51±29 mmHg, aortic valve area 0.63±0.25 cm². Thirty-three patients did not undergo aortic valve replacement: 32 of them died within 3 years. Fifty-two patients underwent aortic valve replacement and 16 had a concomitant coronary bypass surgery. In-hospital mortality was 8%. Postoperative NYHA functional class changed from 2.84±0.67 to 1.43±0.44 (P<0.001) and LVEF from 29±6% to 43±10% (P<0.001). At follow-up 10 patients died of heart disease. By multivariate analysis, preoperative LV end-systolic volume index (ESVI) was the only covariate of cardiac death (LVESVI/10 ml/m², OR 1.3, CI 1.1–1.8, P<0.028). By using a receiver operating characteristic curve, LVESVI≤90 ml/m² was the best cut-off value (sensitivity and specificity 78%) to fit with a better survival (93% vs. 63%, P<0.01) and with LVEF recovery after aortic valve replacement (EF improved by 15±10% vs. 8±5%, P<0.001). Conclusions: Despite LV dysfunction, aortic valve replacement appears to change drastically the natural history of severe aortic stenosis. Preoperative LV levels predict different postoperative survival rate and LVEF recovery.     

Aortic valve replacement in geriatric patients: determinants of in-hospital mortality

BACKGROUND: Aortic valve replacement is a common procedure in elderly patients. There has been a great deal of controversy about the risks associated with early mortality. Uncertainty of the risk associated with a small valve continues to remain controversial. This study was designed to identify the risk factors influencing early mortality and establish an accurate model for the prediction of in-hospital mortality. METHODS: One hundred eighty septuagenarians and octogenarians (58% women; mean age, 76 +/- 4.7 years) underwent primary isolated aortic valve replacement between 1986 and 1997. There was an overall mortality of 16.7% (n = 180). Patients with a body surface area less than 1.8 m2 had an in-hospital mortality of 23.2% (n = 95) compared with 8.1% (n = 74; p = 0.009) for patients with a body surface area of 1.8 m2 or more. Patients with a cardiopulmonary bypass time of less than 100 minutes experienced an early mortality of 8.9% (n = 56) compared with a 10.2% (n = 59) early mortality for patients on bypass time between 100 and 124 minutes and a 29.6% (n = 64) early mortality in patients with a pump time longer than 124 minutes (p = 0.040). RESULTS: Multivariate logistic regression analysis identified small body surface area and long cardiopulmonary bypass time as independent risk factors. A higher mortality was seen in female patients and patients receiving smaller valves. However, there was a strong correlation between small body surface area, small valve size, and female gender. CONCLUSIONS: Small body surface area and long cardiopulmonary bypass time are two independent risk factors in early mortality for elderly patients undergoing primary isolated aortic valve replacement. The use of small valves does not influence early mortality.     

Retrospective study of 412 aortic valve replacements by Bjork-Shiley prosthesis implanted between January 1972 and October 1984. Actuarial survival, mortality, complications

Between January 1972 and October 1984, 412 aortic valve replacements by Bjork-Shiley disk prosthesis were performed. 183 patients suffered from aortic incompetence, 132 from an aortic disease and 97 from aortic stenosis. 116 associated procedures (28%) were performed = 36 myocardial revascularizations, 61 Bentall operations, 12 patch grafts to the ascending aorta and 7 Wheat operations. The mean age was 53.6 years and 25% of the patients were over the age of 65 years. Fifty percent of the patients had stage III or IV disease according to the NYHA classification. The cardiac index was less than 2.3 l/min/m2 in 44.26% of cases. The early postoperative mortality was 4.85% and 20% of these deaths were related to the prosthesis. The late mortality was 17.25%, with 20% of deaths related to the valve. The mean follow-up 59.75 +/- 2 months (range: 1 to 166 months) with a cumulative survival of 2.092 patients-years. It was significantly influence by the existence of preoperative angina, another operation associated with AVR and a cardiac index less than 2.3 l/min/m2. Seventy-one complications were related to the prosthesis including dysfunction (0.05% patient-year), 3 valve thromboses (0.15% patient-year), 6 infected valves (0.31% patient-year), 12 cases of peri-prosthetic dehiscence (0.61% patient-year), 10 embolic complications (0.61% patient-year) and 37 complications related to anticoagulants, including 26 major complications (1.48% patient-year). The valve failure rate was 1.19% patient-year. The results of our series are comparable to those reported in the literature, which confirm the reliability of the Bjork-Shiley Valve.     

丙泊酚麻醉三低状态对瓣膜置换术患者30天死亡风险的影响

目的 拟确立影响瓣膜置换患者术后30 d病死率的丙泊酚麻醉三低[低BIS、低MAP和低效应室靶控浓度(target effect-site concentration,Ce)]阈值. 方法 161例择期拟行单纯瓣膜置换术的成年风湿性心脏病患者,BIS监测下行丙泊酚效应室靶控麻醉,术后随访30 d,根据预后不同将患者分为存活组(155例)和死亡组(6例),建立单因素和多因素回归模型分析风险因素. 结果 BIS＜45、MAP＜65 mmHg(1mrmHg=0.133 kPa)、Ce＜1.5 mg/L的积累时间和三低同时出现的累积时间:死亡组[(278±95)、(153±41)、(125±40)、(58±16) min],较存活组[(163±53)、(65±21)、(63±20)、(21±6) min]均明显延长(P＜0.05).单因素回归模型中:有无吸烟史,术前有无合并症,BIS＜45、MAP＜65 mmHg、Ce＜1.5 mg/L的积累时间和三低同时出现的累积时间,平均手术、麻醉和转机时间及术后ICU驻留时间,均是增加30 d病死率的风险因素(P＜0.05).多因素回归分析显示,三低累积时间和ICU驻留时间仍然是增加术后30 d病死率的危险因素(P＜0.05). 结论 丙泊酚麻醉三低状态(BIS＜45、MAP＜65 mmHg和Ce＜1.5mg/L)和ICU驻留时间是增加瓣膜置换患者术后30 d死亡风险的独立因素.     

The Society of Thoracic Surgeons: 30-day operative mortality and morbidity risk models

BACKGROUND: Although 30 day risk-adjusted operative mortality (ROM) has been used for quality assessment, it is not sufficient to describe the outcomes after coronary artery bypass grafting (CABG) surgery. Risk-adjusted major morbidity may differentially impact quality of care (as complications occur more frequently than death) and enhance a surgical team's ability to assess their quality. This study identified the preoperative risk factors associated with several complications and a composite outcome (the presence of any major morbidity or 30-day operative mortality or both). METHODS: For CABG procedures, the 1997 to 1999 Society of Thoracic Surgeons (STS) National Adult Cardiac Surgery Database was used to develop ROM and risk-adjusted morbidity (ROMB) models. Risk factors were selected using standard STS univariate screening and multivariate logistic regression approaches. Risk model performance was assessed. Across STS participating sites, the association of observed-to-expected (O/E) ratios for ROM and ROMB was evaluated. RESULTS: The 30-day operative death and major complication rates for STS CABG procedures were 3.05% and 13.40%, respectively (503,478 CABG procedures), including stroke (1.63%), renal failure (3.53%), reoperation (5.17%), prolonged ventilation (5.96%), and sternal infection (0.63%). Risk models were developed (c-indexes for stroke [0.72], renal failure [0.76], reoperation [0.64], prolonged ventilation [0.75], sternal infection [0.66], and the composite endpoint [0.71]). Only a slight correlation was found, however, between ROMB and ROM indicators. CONCLUSIONS: Used in combination, ROMB and ROM may provide the surgical team with additional information to evaluate the quality of their care as well as valuable insights to allow them to focus on areas for improvement.     

Procedural, 30-day and one year outcome following CoreValve or Edwards transcatheter aortic valve implantation: results of the Belgian national registry

We report clinical outcomes following transcatheter aortic valve implantation (TAVI), using the CoreValve revalving system (18 Fr transfemoral or subclavian) or the Edwards Sapien valve (22 Fr transfemoral or 24 Fr transapical) as part of a Belgian prospective non-randomized multicentre registry. All 15 Belgian centres performing TAVI participated to this registry (seven exclusively Edwards Sapien, eight exclusively CoreValve). All consecutive high-risk symptomatic patients with severe aortic stenosis were evaluated by a heart team and screened for eligibility for TAVI. Three hundred and twenty-eight patients underwent TAVI with CoreValve (n = 141; eight subclavian and 133 transfemoral) or Edwards Sapien (n = 187; 99 transfemoral and 88 transapical) up to April 2010. Procedural success was 97%. One-month survival was 88% for the Edwards and 89% for the CoreValve treated patients. One-month mortality was both related to cardiac and non-cardiac reasons. Overall one-year survival was 78% in the CoreValve transfemoral treated patients, 100% in the CoreValve subclavian treated patients, 82% in the Edwards transfemoral treated patients and 63% in the Edwards transapical treated patients. This mid-term mortality was mainly related to age-related, non-cardiac complications.     

Standard aortic St. Jude valve at 18 years: performance profile and determinants of outcome

BACKGROUND: The standard St. Jude disc valve has been in use for 20 years and remains the dominant mechanical valve of today. With nearly 19 years of follow-up, the present large series could indicate the performance profile and its determinants in the very long term. METHODS: A detailed follow-up was performed to a maximum of 18.6 years in 694 patients aged 15 to 83 years who undervent aortic valve replacement (AVR) with the standard St. Jude valve during 1980 to 1993. The Cox regression analysis was used to identify independent determinants of outcome in the aortic stenosis (n = 490) and regurgitation (n = 204) groups. RESULTS: Overall survival was 58%, 39%, and 37% at 10, 15, and 18 years, respectively. Only 12% of deaths (0.60%/ patient-year) were related to the valve with a 15-year freedom of 91%. Embolism (1.18%/patient-year) and anticoagulant-related bleeding (2.24%/patient-year) were the dominant complications with 10-year/15-year freedoms of 90%/80% and 85%/72%, respectively. Only 24% of bleeding events were classified as major. Valve thrombosis occurred in 2 patients (0.04%/patient-year): 1 did not receive vitamin K antagonist treatment and International Normalized Ratio was below target level in the other. There were no mechanical failures. Endocarditis (0.42%/patient-year) and paravalvular leak (0.42%/ patient-year) occurred with 15-year freedoms of 92% and 96%, respectively, with a relation between the latter (but not the former) and preoperative endocarditis in the regurgitation group. Freedom from serious complications (2.33%/patient-year) and all complications joined (4.33%/ patient-year) were 72% and 54%, respectively, at 15 years with a 96% freedom from redo AVR (0.36%/patient-year). Age- and heart-related variables were independent risk factors for mortality, thromboembolism, bleeding, serious complications, and all complications joined. Small valve (19 and 21 mm) adversely affected serious and all complications in the regurgitation group. CONCLUSIONS: With a follow-up approaching 2 decades and exhibiting a low rate of valve-related deaths, acceptable low thrombogenicity, and absence of mechanical failure, the standard aortic St. Jude disc valve sets the standard for contemporary mechanical valves.     

Trauma patients in the intensive care unit: short- and long-term survival and predictors of 30-day mortality

BACKGROUND: The aims of this cohort study were to assess the survival of trauma patients treated in a general intensive care unit (ICU) and to evaluate the simplified acute physiology score (SAPS) II, maximum sequential organ failure assessment (SOFA) score, injury severity score (ISS), age, sex and severe head injury as predictors of 30-day mortality. METHODS: Three hundred and twenty-five adult patients admitted during 1998-2003 were evaluated retrospectively with update of survival data in January 2005. Kaplan-Meier statistics and Cox proportional hazards regression were used to study survival and to assess predictors of mortality, respectively. RESULTS: The 30-day mortality was 16.9%, ICU mortality 13.8% and hospital mortality 17.8%. Long-term survival (observation time, 1-7 years) was 77.8%. After 3.5 years, mortality was the same as for the background population. Severe head injury was the main cause of death and increased the risk of 30-day mortality 2.4-fold. In addition, SAPS II and an age above 50 years proved to be significant predictors of mortality in a multivariate analysis. Sex was not associated with mortality, and ISS and the maximum SOFA score were significant predictors in univariate analyses only. CONCLUSION: Reduced long-term survival was observed up to 3.5 years after acute injury. The 30-day mortality was strongly related to severe head injury, SAPS II and an age above 50 years. These variables may be useful as predictors of mortality, and may contribute to risk adjustment of this subset of trauma patients when treatment results from different centres are compared.     

经导管植入国产自膨式主动脉瓣膜治疗老年性主动脉瓣狭窄(附3例报告)

正75岁以上的老年人退行性心脏瓣膜病发病率高达4.6%~([1])。老年性主动脉瓣狭窄(aortic valve stenosis,AS)发病率越来越高。目前外科主动脉瓣膜置换术(surgery aortic valve replacement,SAVR)仍是治疗重度AS的首选方法,但30%~50%的患者因存在严重合并症、无法承受外科手术而出现心力衰竭和心源性猝死。2002年Cribier等~([2])采用经导管主动     

Evolution of allograft aortic valve replacement over 13 years: results of 275 procedures.

OBJECTIVE: We describe our center's experience with the use of allografts for aortic valve or root replacement, illustrating the impact on outcome of the changes made in surgical and preservation techniques. METHODS: Between 4/1987 and 1/2001 275 allografts were used in 267 consecutive patients to replace the aortic valve or root. All patients were prospectively followed over time. Mean patient age was 46 years (SD 16; range 0.06-83), male/female ratio was 201/74. Prior cardiac operations took place in 73 patients; 49 patients presented with active endocarditis. Pre-operative NYHA-class was III in 51%. Initially, the subcoronary technique was used (SC; N=95) while in recent years root replacement (ARR; N=180) became the technique of choice. Seven fresh (two pulmonary and five aortic) and 268 cryopreserved (four pulmonary and 264 aortic; 35 glycerol and 233 DMSO) allografts were implanted. Concomitant procedures took place in 133 (48%). RESULTS: Operative mortality was 5.5% (N=15) and during follow-up (99% complete) 29 more patients died. Overall cumulative survival was 73% (95% CI 65-81%) at 9 years postoperative and significantly better for SC compared to ARR patients (P=0.005). Freedom from allograft-related reoperation (N=34) was 77% (95% CI 69-85) at 9 years, and worse in the SC compared to ARR group due to increased early technical failure (P=0.03). Freedom from reoperation for structural valve deterioration (SVD; N=22) was 81% (95% CI 73-89) at 9 years and did not differ between SC and ARR (P=0.51). Independent predictors of degenerative SVD were younger patient age (HR 0.93 with age as continuous variable; 95% CI 0.90-0.97), older donor age (HR 1.06 with age as a continuous variable; 95% CI 1.00-1.11), larger allograft diameter (HR 1.38; 95% CI 1.11-1.71) and the use of pulmonary allografts (HR 10.72; 95% CI 3.88-29.63). Calculated median time to reoperation for structural valve deterioration ranged from 23 years in a 65-year-old patient to 12 years in a 25-year-old. CONCLUSIONS: Aortic valve replacement with allografts yields adequate midterm results. Although important changes have been made over the years to improve durability, allografts still have a limited life span especially in young patients.     

Performance and usability of pre-operative prediction models for 30-day peri-operative mortality risk: a systematic review

Estimating pre-operative mortality risk may inform clinical decision-making for peri-operative care. However, pre-operative mortality risk prediction models are rarely implemented in routine clinical practice. High predictive accuracy and clinical usability are essential for acceptance and clinical implementation. In this systematic review, we identified and appraised prediction models for 30-day postoperative mortality in non-cardiac surgical cohorts. PubMed and Embase were searched up to December 2022 for studies investigating pre-operative prediction models for 30-day mortality. We assessed predictive performance in terms of discrimination and calibration. Risk of bias was evaluated using a tool to assess the risk of bias and applicability of prediction model studies. To further inform potential adoption, we also assessed clinical usability for selected models. In all, 15 studies evaluating 10 prediction models were included. Discrimination ranged from a c-statistic of 0.82 (MySurgeryRisk) to 0.96 (extreme gradient boosting machine learning model). Calibration was reported in only six studies. Model performance was highest for the surgical outcome risk tool (SORT) and its external validations. Clinical usability was highest for the surgical risk pre-operative assessment system. The SORT and risk quantification index also scored high on clinical usability. We found unclear or high risk of bias in the development of all models. The SORT showed the best combination of predictive performance and clinical usability and has been externally validated in several heterogeneous cohorts. To improve clinical uptake, full integration of reliable models with sufficient face validity within the electronic health record is imperative.