Systematic review and narrative synthesis of surgeons’ perception of postoperative outcomes and risk

Background The accuracy with which surgeons can predict outcomes following surgery has not been explored in a systematic way. The aim of this review was to determine how accurately a surgeon's ‘gut feeling’ or perception of risk correlates with patient outcomes and available risk scoring systems. Methods A systematic review was undertaken in accordance with PRISMA guidelines. A narrative synthesis was performed in accordance with the Guidance on the Conduct of Narrative Synthesis In Systematic Reviews. Studies comparing surgeons' preoperative or postoperative assessment of patient outcomes were included. Studies that made comparisons with risk scoring tools were also included. Outcomes evaluated were postoperative mortality, general and operation‐specific morbidity and long‐term outcomes. Results Twenty‐seven studies comprising 20 898 patients undergoing general, gastrointestinal, cardiothoracic, orthopaedic, vascular, urology, endocrine and neurosurgical operations were included. Surgeons consistently overpredicted mortality rates and were outperformed by existing risk scoring tools in six of seven studies comparing area under receiver operating characteristic (ROC) curves (AUC). Surgeons' prediction of general morbidity was good, and was equivalent to, or better than, pre‐existing risk prediction models. Long‐term outcomes were poorly predicted by surgeons, with AUC values ranging from 0·51 to 0·75. Four of five studies found postoperative risk estimates to be more accurate than those made before surgery. Conclusion Surgeons consistently overestimate mortality risk and are outperformed by pre‐existing tools; prediction of longer‐term outcomes is also poor. Surgeons should consider the use of risk prediction tools when available to inform clinical decision‐making. Introduction Surgical procedures all carry associated risks. It is therefore important that surgeons are able to make accurate predictions of potential benefit and risk, including immediate mortality and morbidity, as well as long‐term outcomes, to enable balanced decision‐making and fully informed consent. Risks can also be estimated after surgery, based on additional perioperative and intraoperative data, which allows contemporary prediction of outcome. There are numerous risk prediction models that enable the surgeon to quantify risk based on measurable parameters1-5. However, there are inherent limitations in using a generalized risk prediction model, which may not include clinical data pertinent to the individual case in question, leading to variability in model accuracy6-10. As a result, risk prediction tools are generally used in tandem with the surgeon's ‘gut feeling’ of overall risk and anticipated outcome (‘clinical gestalt’). Several disparate factors influence surgeons' perception of outcome: patient factors, such as their perceived fitness, their pathology and planned procedure; setting factors, such as the experience of other members of staff; and surgeon factors, such as clinical knowledge, operative skill, previous significant surgical complications, and inclinations and attitudes11-13. Anticipating surgical risk is subject to multiple biases, which make it challenging. These include the natural tendency toward anecdotal recall and the availability heuristic (the likelihood of making a decision based on how easily the topic or examples come to mind)14, 15. Some studies16-18 support the accuracy and reproducibility of surgeons' predictions, whereas others19-22 demonstrate less favourable results. The complexity of synthesizing risk perceptions is significant and incompletely understood23, 24. The accuracy of surgeons' prediction has not been explored previously in a systematic manner. The aim of this review was thus to determine, from the available evidence, whether a surgeon's gut feeling or perception of risk correlates with postoperative outcomes, and to compare this prediction with currently available risk scoring systems, where available. Methods This systematic review was undertaken in accordance with the PRISMA guidelines25, 26. MEDLINE (via PubMed), Embase, the Cochrane Library Database, and the Cochrane Collaboration Central Register of Controlled Clinical Trials were searched with no date or language restrictions, with the last search date on 9 July 2018. The search term used was (‘Surgeons’[Mesh] OR ‘General Surgery/manpower*’ [MeSH]) AND (‘perception’ OR ‘intuition’ OR ‘predict*’ OR ‘decision making’ [mesh]). There was no restriction on publication type. This search was complemented by an exhaustive review of the bibliography of key articles, and also by using the Related Articles function in PubMed of included papers. Results were restricted to human research published in English. Inclusion and exclusion criteria All studies of patients undergoing surgery in which a preoperative or postoperative surgeon assessment (or proxy assessment) of a postoperative outcome was performed were included. This included articles that reported general risk (such as mortality) or a surgery‐specific risk (for example anastomotic leakage). Studies that made comparisons with established risk scoring tools were also included. Papers or abstracts in English, or non‐English papers with an English abstract, were included. Papers describing the risk assessment of ‘theoretical’ cases, or patient vignettes in a situation distant from clinical practice (such as a conference), were excluded, as were studies in which surgeons' assessment of risk was compared with an established risk scoring tool, without data on actual patient outcome. Data extraction and assessment of study quality Three authors independently extracted data and assessed the methodological quality of the studies, with all data extraction independently checked by the senior author. The following baseline data were extracted from each study: first author, year of publication, data collection period, geographical location, study design and type (single or multiple centres, number of surgeons involved in risk estimation, whether consecutive patients were enrolled), surgical specialty, whether other risk scoring systems were used for comparison and, if so, whether the assessor was blinded to this result. Data extracted regarding the assessment of risk included: risk outcome assessed; timing of risk estimation (preoperative or postoperative); type of risk assessment by surgeons (qualitative, quantitative, continuous scale such as a visual analogue scale (VAS), or composite score); absolute value of risk event predicted by surgeon and by scoring system; absolute value of risk occurrence rate; summary data on outcome reported, including area under the curve (AUC) of receiver operating characteristic (ROC) curves, observed : expected (O : E) or predicted : observed (P : O) ratios, or any other summary data. When data were available, AUCs were extracted with their 95 per cent confidence intervals. AUCs greater than 0·9 were considered as indicating high performance, 0·7–0·9 as moderate performance, 0·5–0·7 as low performance, and less than 0·5 as indicating risk assessment no better than chance alone27, 28. Risk predictions made by pre‐existing tools, such as the Physiological and Operative Severity Score for the enumeration of Mortality and morbidity (POSSUM)1, Portsmouth‐POSSUM (P‐POSSUM)4 or Continuous Improvement in Cardiac Surgery Program (CICSP)5, were compared with outcome when given. Internal prediction models, where authors would derive significant predictive co‐variables from their data set and assess the accuracy of these co‐variables within the same data set, were not evaluated as they lacked validity. Study quality was assessed using the Newcastle–Ottawa (NO) score29, 30. The NO score assigns points based on: the quality of patient selection (maximum 4 points); comparability of the cohort (maximum 2 points); and outcome assessment (maximum 3 points). Studies that scored 6 points or more were considered to be of higher quality. Outcome measures The following outcome measures were defined a priori and refined during data extraction: postoperative mortality (usually defined as 30 days after surgery); postoperative general morbidity (usually defined as 30 days after surgery); postoperative procedure‐specific morbidity; and long‐term outcome (typically operation‐specific). Further comparative analyses of outcomes included comparison of preoperative and postoperative predictions, and of predictions made by consultants and surgical trainees. Narrative synthesis Given the marked heterogeneity in study design, patient population included, method of assessing risk and outcomes assessed, meta‐analysis was deemed not appropriate. A narrative synthesis was therefore performed according to the Guidance on the Conduct of Narrative Synthesis In Systematic Reviews31. Three authors systematically summarized each article using bullet points to document key aspects of each study, focusing particularly on methods used and results obtained. The validity and certainty of the results were noted (whether appropriate statistical comparisons were used and, if so, their effect size and significance). The senior author identified and grouped common themes, divided larger themes into subthemes, tabulated a combined summary of the paper, and synthesized a common rubric for each theme. Consolidated reviewers' comments can be found in Table S1 (supporting information). Results A total of 584 articles were identified from the literature search, of which 48 were retrieved for evaluation. Papers were excluded on the basis of being duplicates (1) and being irrelevant based on the title (497) and abstract (38) (Fig. 1). Twenty‐seven studies16-24, 32-49 comprising 20 898 patients met the inclusion criteria and were included in the narrative synthesis (Appendix S1, supporting information)

Umbrella review and meta‐analysis of antiplatelet therapy for peripheral artery disease

Background The literature on antiplatelet therapy for peripheral artery disease has historically been summarized inconsistently, leading to conflict between international guidelines. An umbrella review and meta‐analysis was performed to summarize the literature, allow assessment of competing safety risks and clinical benefits, and identify weak areas for future research. Methods MEDLINE, Embase, DARE, PROSPERO and Cochrane databases were searched from inception until January 2019. All meta‐analyses of antiplatelet therapy in peripheral artery disease were included. Quality was assessed using AMSTAR scores, and GRADE analysis was used to quantify the strength of evidence. Data were pooled using random‐effects models. Results Twenty‐eight meta‐analyses were included. Thirty‐three clinical outcomes and 41 antiplatelet comparisons in 72 181 patients were analysed. High‐quality evidence showed that antiplatelet monotherapy reduced non‐fatal strokes (3 (95 per cent c.i. 0 to 6) fewer per 1000 patients), In symptomatic patients, it reduced cardiovascular deaths (8 (0 to 16) fewer per 1000 patients), but increased the risk of major bleeding (7 (3 to 14) more events per 1000). In asymptomatic patients, monotherapy reduced non‐fatal strokes (5 (0 to 8) fewer per 1000), but had no other clinical benefit. Dual antiplatelet therapy caused more major bleeding after intervention than monotherapy (37 (8 to 102) more events per 1000), with very low‐quality evidence of improved endovascular patency (risk ratio 4·00, 95 per cent c.i. 0·91 to 17·68). Conclusion Antiplatelet monotherapy has minimal clinical benefit for asymptomatic peripheral artery disease, and limited benefit for symptomatic disease, with a clear risk of major bleeding. There is a lack of evidence to guide antiplatelet prescribing after peripheral endovascular intervention

The long road to elimination: malaria mortality in a South African population cohort over 21 years.

BACKGROUND: Malaria elimination is on global agendas following successful transmission reductions. Nevertheless moving from low to zero transmission is challenging. South Africa has an elimination target of 2018, which may or may not be realised in its hypoendemic areas. METHODS: The Agincourt Health and Demographic Surveillance System has monitored population health in north-eastern South Africa since 1992. Malaria deaths were analysed against individual factors, socioeconomic status, labour migration and weather over a 21-year period, eliciting trends over time and associations with covariates. RESULTS: Of 13 251 registered deaths over 1.58 million person-years, 1.2% were attributed to malaria. Malaria mortality rates increased from 1992 to 2013, while mean daily maximum temperature rose by 1.5 °C. Travel to endemic Mozambique became easier, and malaria mortality increased in higher socioeconomic groups. Overall, malaria mortality was significantly associated with age, socioeconomic status, labour migration and employment, yearly rainfall and higher rainfall/temperature shortly before death. CONCLUSIONS: Malaria persists as a small but important cause of death in this semi-rural South African population. Detailed longitudinal population data were crucial for these analyses. The findings highlight practical political, socioeconomic and environmental difficulties that may also be encountered elsewhere in moving from low-transmission scenarios to malaria elimination

Single versus dual antiplatelet therapy following peripheral arterial endovascular intervention for chronic limb threatening ischaemia:retrospective cohort study

ObjectivesAntiplatelet therapy following peripheral arterial endovascular intervention lacks high quality evidence to guide practice. The aim of this study was to assess the effect of three months of dual antiplatelet therapy on amputation-free survival following peripheral arterial endovascular intervention in patients with chronic limb threatening ischemia.MethodsA retrospective review of symptomatic patients undergoing primary peripheral arterial endovascular intervention over a seven-year period was performed. The primary outcome measure was amputation-free survival. A sample size calculation based on previous cohort studies suggested that 629 limbs would be required to show a difference between single and dual therapy. Kaplan-Meier estimates and multivariate logistic regression analysis of recorded baseline characteristics was performed to determine predictors of amputation-free survival. Dual antiplatelet therapy was routinely given for 3 months.Results754 limbs were treated with primary angioplasty and/or stenting over a 7-year period, 508 of these for chronic limb threatening ischemia. There was no difference in unadjusted amputation-free survival between patients with chronic limb threatening ischaemia taking single vs. dual antiplatelet therapy (69% vs. 74% respectively Log rank Chi2 = 0.1, p = .72). After adjusting for confounders, at 1 year there was also no significant difference in amputation-free survival between patients taking single vs. dual antiplatelet therapy [OR 0.8, 95% CI 0.5-1.2, p = .3]. There was no difference in rates of major bleeding between single and dual antiplatelet therapy.ConclusionsThere was no clear evidence of reduced amputation-free survival in patients with chronic limb threatening ischemia undergoing peripheral arterial endovascular intervention being treated with dual antiplatelet therapy for 3 months. This is at odds with other retrospective case series and highlights the limitations in basing clinical practice on such data. There is a need for an adequately powered, independent randomised trial to definitively answer the question

Development of core outcome sets for people undergoing major lower limb amputation for complications of peripheral vascular disease

Objective Every year, thousands of patients with peripheral vascular disease undergo major lower limb amputation. Despite this, evidence for optimal management is weak. Core outcome sets capture consensus on the most important outcomes for a patient group to improve the consistency and quality of research. The aim was to define short and medium term core outcome sets for studies involving patients undergoing major lower limb amputation. Methods A systematic review of the literature and focus groups involving patients, carers, and healthcare professionals were used to derive a list of potential outcomes. Findings informed a three round online Delphi consensus process, where outcomes were rated for both short and medium term studies. The results of the Delphi process were discussed at a face to face consensus meeting, and recommendations were made for each core outcome set. Results A systematic review revealed 45 themes to cazrry forward to the consensus survey. These were supplemented by a further five from focus groups. The consensus survey received responses from 123 participants in round one, and 91 individuals completed all three rounds. In the final round, nine outcomes were rated as “core” for short term studies and a further nine for medium term studies. Wound infection and healing were rated as “core” for both short and medium term studies. Outcomes related to mortality, quality of life, communication, and additional healthcare needs were also rated as “core” for short term studies. In medium term studies, outcomes related to quality of life, mobility, and social integration/independence were rated as “core”. The face to face stakeholder meeting ratified inclusion of all outcomes from the Delphi and suggested that deterioration of the other leg and psychological morbidity should also be reported for both short and medium term studies. Conclusion Consensus was established on 11 core outcomes for short and medium term studies. It is recommended that all future studies involving patients undergoing major lower limb amputation should report these outcomes

Angiosome specific revascularisation: does the evidence support it?

Objective To explain the angiosome concept and explore the practical application of the angiosome literature to a clinical scenario, in this case a tibial angioplasty for critical ischaemia. Methods Clinical vignette with explanation of the decisions made and subsequent clinical results based on the theory of the angiosome concept and the literature on angiosomal revascularisation; in this case the results of our group’s recent update to a systematic review and meta-analysis. Results Endovascular combined or direct angiosomal revascularisation if superior to indirect revascularisation. This was borne out in the clinical scenario, where an indirect peroneal reperfusion of the AT angiosome resulted in major amputation. Open surgery is less dependent on the angiosome concept. The presence of adequate collateralisation into a foot arch seems to be the most important factor predicting success of indirect revascularisation. The evidence for both suffers from selection bias and many of the findings in the literature are wholly due to selection bias. Conclusion The angiosome concept is useful during both open and endovascular tibial revascularisation. However, the runoff in the foot is critical to success and may not follow the ‘classic’ angiosome model in diabetes

The CLEAR (Considering Leading Experts’ Antithrombotic Regimes around peripheral angioplasty) survey:an international perspective on antiplatelet and anticoagulant practice for peripheral arterial endovascular intervention

BACKGROUND: Antiplatelet and anticoagulant therapy are commonly used before, during and after peripheral arterial endovascular intervention. This survey aimed to establish antiplatelet and anticoagulant choice for peripheral arterial endovascular intervention in contemporary clinical practice. METHODS: Pilot-tested questionnaire distributed via collaborative research networks. RESULTS: One hundred and sixty-two complete responses were collected from responders in 22 countries, predominantly the UK (48%) and the rest of the European Union (44%). Antiplatelet monotherapy was the most common choice pre-procedurally (62%). In the UK, there was no difference between dual and single antiplatelet therapy use post procedure (50% vs. 37% p = 0.107). However, a significant majority of EU respondents used dual therapy (68% vs. 20% p < 0.001). There was variation in choice of antiplatelet therapy by the device used and the anatomical location of the intervention artery. The majority (82%) of respondents believed there was insufficient evidence to guide antithrombotic therapy after peripheral endovascular intervention and most (92%) would support a randomised trial. CONCLUSIONS: There is widespread variation in the use of antiplatelet therapy, especially post peripheral arterial endovascular intervention. Clinicians would support the development of a randomised trial comparing dual antiplatelet therapy with monotherapy

The CLEAR (considering leading experts' antithrombotic regimes around peripheral angioplasty) survey: an international perspective on antiplatelet and anticoagulant practice for peripheral arterial endovascular intervention.

Background Antiplatelet and anticoagulant therapy are commonly used before, during and after peripheral arterial endovascular intervention. This survey aimed to establish antiplatelet and anticoagulant choice for peripheral arterial endovascular intervention in contemporary clinical practice. Methods Pilot-tested questionnaire distributed via collaborative research networks. Results One hundred and sixty-two complete responses were collected from responders in 22 countries, predominantly the UK (48%) and the rest of the European Union (44%). Antiplatelet monotherapy was the most common choice pre-procedurally (62%). In the UK, there was no difference between dual and single antiplatelet therapy use post procedure (50% vs. 37% p = 0.107). However, a significant majority of EU respondents used dual therapy (68% vs. 20% p < 0.001). There was variation in choice of antiplatelet therapy by the device used and the anatomical location of the intervention artery. The majority (82%) of respondents believed there was insufficient evidence to guide antithrombotic therapy after peripheral endovascular intervention and most (92%) would support a randomised trial. Conclusions There is widespread variation in the use of antiplatelet therapy, especially post peripheral arterial endovascular intervention. Clinicians would support the development of a randomised trial comparing dual antiplatelet therapy with monotherapy