Evidence-Based Surgery PDF

Using scientific evidence in Surgery Stavros A Antoniou MD PhD MPH FEBS General Surgeon Papageorgiou General Hospital Case scenario ED, tertiary care center 32-yo pregnant, 9th week of pregnancy Pain, tenderness in the right lower abdominal f...

Using scientific evidence in Surgery Stavros A Antoniou MD PhD MPH FEBS General Surgeon Papageorgiou General Hospital Case scenario ED, tertiary care center 32-yo pregnant, 9th week of pregnancy Pain, tenderness in the right lower abdominal fossa US: acute uncomplicated appendicitis Your attending suggests watchful waiting You are not sure what is the right thing to do Case scenario A. Read a textbook B. Ask another consultant C. Search the web D. Use AI E. Search PubMed Case scenario A. Read a textbook B. Ask another consultant C. Search the web D. Use AI E. Search PubMed Case scenario A. Read a textbook B. Ask another consultant C. Search the web D. Use AI E. Search PubMed Case scenario A. Read a textbook B. Ask another consultant C. Search the web D. Use AI E. Search PubMed Case scenario A. Read a textbook B. Ask another consultant C. Search the web D. Use AI E. Search PubMed Case scenario A. Read a textbook B. Ask another consultant C. Search the web D. Use AI E. Search PubMed Case scenario (pregnan* AND appendicit*) AND (treatment OR management) Case scenario (pregnan* AND appendicit*) AND (treatment OR management) Article type: Systematic review Case scenario (pregnan* AND appendicit*) AND (treatment OR management) Article type: Systematic review Case scenario What if… No guideline? Systematic review Summary of evidence on a specific topic Systematic search +/- meta-analysis PICO Patient (population) Intervention (exposure) Comparator (control) Outcome(s) Systematic review Created by AmruID from the Noun Project Created by AmruID from the Noun Project Created by AmruID from the Noun Project Created by AmruID from the Noun Project Systematic review Collect evidence Synthesize evidence Appraise evidence Systematic review Collect evidence Systematic review RCTs and/or observational studies Synthesize evidence Appraise evidence Systematic review Collect evidence Meta-analysis Synthesize evidence Network meta-analysis Time-to-event meta-analysis Appraise evidence IPD meta-analysis Systematic review Very low – “We are uncertain” Collect evidence Low – “The intervention may be effective” Synthesize evidence Appraise evidence Moderate – “The intervention is likely effective” High – “The intervention is effective” Systematic review Collect evidence Synthesize evidence Appraise evidence Systematic review Risk of bias Collect evidence Inconsistency Synthesize evidence Indirectness Appraise evidence Imprecision Publication bias Systematic review RoB-2 Risk of bias Collect evidence ROBINS-I Inconsistency Synthesize evidence Indirectness Appraise evidence Imprecision Publication bias Systematic review Visual inspection Risk of bias I2 Collect evidence Inconsistency τ2 Synthesize evidence Indirectness Explained? Appraise evidence Imprecision Publication bias Systematic review Risk of bias Collect evidence Inconsistency Synthesize evidence Indirectness Appraise evidence Imprecision Publication bias Systematic review Risk of bias Collect evidence Inconsistency Synthesize evidence Indirectness Appraise evidence Imprecision Publication bias Systematic review Risk of bias Collect evidence Patients Inconsistency Intervention Synthesize evidence Indirectness Comparator Imprecision Appraise evidence Outcome Publication bias Systematic review Risk of bias Collect evidence Inconsistency Synthesize evidence Indirectness Appraise evidence Imprecision Publication bias Heparin vs no heparin to prevent VTE in patients with cancer favors heparin favors no heparin Heparin vs no heparin to prevent VTE in patients with cancer favors heparin favors no heparin Heparin vs no heparin to prevent VTE in patients with cancer favors heparin favors no heparin Heparin vs no heparin to prevent VTE in patients with cancer favors heparin favors no heparin Heparin vs no heparin to prevent VTE in patients with cancer “Heparin does not prevent VTE” favors heparin favors no heparin Heparin vs no heparin to prevent VTE in patients with cancer “Heparin prevents VTE” favors heparin favors no heparin Heparin vs no heparin to prevent VTE in patients with cancer “Heparin may prevent VTE” favors heparin favors no heparin Heparin vs no heparin to prevent VTE in patients with cancer “Heparin prevents VTE, no significant effect” favors heparin favors no heparin Heparin vs no heparin to prevent VTE in patients with cancer “Heparin may prevent VTE, no significant effect” favors heparin favors no heparin Heparin vs no heparin to prevent VTE in patients with cancer “We are uncertain” favors heparin favors no heparin Systematic review Risk of bias Collect evidence Inconsistency Synthesize evidence Indirectness Appraise evidence Imprecision Publication bias Evidence to decision Benefits vs risks (or burden) – prevention of VTE 1/100 vs severe bleeding in 10/100 Evidence to decision Benefits vs risks (or burden) Overall certainty of the evidence – low for skin erythema, moderate for prevention of VTE Evidence to decision Benefits vs risks (or burden) Overall certainty of the evidence Patients’ values and preferences – chemotherapy for stage IV colon cancer in frail patients Evidence to decision Benefits vs risks (or burden) Overall certainty of the evidence Patients’ values and preferences – colostomy in patients with low rectal cancer Evidence to decision Benefits vs risks (or burden) Overall certainty of the evidence Patients’ values and preferences – mastectomy vs breast-conserving surgery in women Evidence to decision Benefits vs risks (or burden) Overall certainty of the evidence Patients’ values and preferences Acceptability – daily injections Evidence to decision Benefits vs risks (or burden) Overall certainty of the evidence Patients’ values and preferences Acceptability Feasibility – robotic surgery for rectal cancer Evidence to decision Benefits vs risks (or burden) Overall certainty of the evidence Patients’ values and preferences Acceptability Feasibility – taTME for rectal cancer Evidence to decision Benefits vs risks (or burden) Overall certainty of the evidence Patients’ values and preferences Acceptability Feasibility Resources - €5,000/day therapy for a year to increase total height by an average of 3cm Evidence to decision Evidence Evidence to decision framework Recommendations Evidence to decision Clear: “We recommend heparin over no heparin in patients with cancer” Precise: “We recommend heparin over no heparin in patients with gastrointestinal cancer” Actionable: “We recommend prophylactic dose of heparin over no heparin in patients with gastrointestinal cancer” Evidence to decision For patients: most individuals in this situation would want the recommended course of action, and only a small proportion would not. For clinicians: most individuals should follow the recommended course of action. Formal decision aids are not likely to be needed to help individual patients make decisions consistent with their values and preferences. For policy makers: the recommendation can be adopted as policy in most situations. Adherence to this recommendation according to the guideline could be used as a quality criterion or performance indicator. For researchers: the recommendation is supported by credible research or other convincing judgments that make additional research unlikely to alter the recommendation. On occasion, a strong recommendation is based on low or very low certainty in the evidence. In such instances, further research may provide important information that alters the recommendation. What if… No systematic review? What if… No systematic review? What if… No systematic review? Risk of bias assessment Evidence appraisal