Postoperative pain and neurocognitive outcomes after noncardiac surgery: a systematic review and dose-response meta-analysis.

BACKGROUND: Postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) are common after noncardiac surgery. Postsurgical pain is frequent and can persist as chronic postsurgical pain (CPSP). The association between postsurgical pain and POD or POCD is biologically plausible. We conducted this systematic review to evaluate the association between acute postsurgical pain or CPSP and POD or POCD in adults undergoing noncardiac surgery. METHODS: We followed Preferred Reporting Items for Systematic Review and Meta-Analyses. We searched MEDLINE, EMBASE, Cochrane, CINAHL and PSYCHINFO up to May 2023. We included cohort, case-control, and cross-sectional studies of any language. Pairs of reviewers independently screened studies, extracted data and assessed the risk of bias using the CLARITY tool and the Joanna Briggs Institute checklist. We assessed the certainty of evidence using the Grading of Recommendations Assessment, Development, and Evaluation approach. Where possible, we conducted random-effects meta-analyses to summarise our findings. RESULTS: We analysed 30 studies (>9000 participants) that assessed the association between acute postoperative pain and POD/POCD. Dose-response meta-analyses found that postoperative pain intensity was associated with occurrence of POD (adjusted relative risk [aRR]/unit of pain intensity: 1.26; 95% confidence interval [CI]: 1.17-1.35; low certainty of evidence) and risk of developing POD (aRR/unit of pain intensity: 1.18; 95% CI: 1.08-1.30; low certainty of evidence). There was very low certainty of evidence regarding the association between postoperative pain and POCD. No studies assessed the association between CPSP and POCD. Residual confounding and substantial methodological variability between studies prevented pooling data from many of the included studies and lowered certainty of evidence. CONCLUSIONS: Dose-response meta-analyses found that postoperative pain intensity was associated with occurrence of and risk of developing POD. SYSTEMATIC REVIEW PROTOCOL: PROSPERO-CRD42021192105.

Perioperative randomised controlled trials: to pilot or not to pilot?

The science of pilot trials is evolving, and understanding of their role in medical research is increasing. Perioperative randomised controlled trials often test interventions that are inherently multidisciplinary and complex; therefore, there might be compelling reasons to conduct pilot studies to assess feasibility and inform trial design. As pilot studies themselves require resources, investigators should not squander this opportunity; they should design them so that they properly address the sources of uncertainty regarding the success of the definitive trial.

Myocardial Injury in Patients with Hip Fracture: A HIP ATTACK Randomized Trial Substudy.

BACKGROUND: Myocardial injury after a hip fracture is common and has a poor prognosis. Patients with a hip fracture and myocardial injury may benefit from accelerated surgery to remove the physiological stress associated with the hip fracture. This study aimed to determine if accelerated surgery is superior to standard care in terms of the 90-day risk of death in patients with a hip fracture who presented with an elevated cardiac biomarker/enzyme measurement at hospital arrival. METHODS: The HIP fracture Accelerated surgical TreaTment And Care tracK (HIP ATTACK) trial was a randomized controlled trial designed to determine whether accelerated surgery for hip fracture was superior to standard care in reducing death or major complications. This substudy is a post-hoc analysis of 1392 patients (from the original study of 2970 patients) who had a cardiac biomarker/enzyme measurement (>99.9% had a troponin measurement and thus "troponin" is the term used throughout the paper) at hospital arrival. The primary outcome was all-cause mortality. The secondary composite outcome included all-cause mortality and non-fatal myocardial infarction, stroke, and congestive heart failure 90 days after randomization. RESULTS: Three hundred and twenty-two (23%) of the 1392 patients had troponin elevation at hospital arrival. Among the patients with troponin elevation, the median time from hip fracture diagnosis to surgery was 6 hours (interquartile range [IQR] = 5 to 13) in the accelerated surgery group and 29 hours (IQR = 19 to 52) in the standard care group. Patients with troponin elevation had a lower risk of mortality with accelerated surgery compared with standard care (17 [10%] of 163 versus 36 [23%] of 159; hazard ratio [HR] = 0.43 [95% confidence interval (CI) = 0.24 to 0.77]) and a lower risk of the secondary composite outcome (23 [14%] of 163 versus 47 [30%] of 159; HR = 0.43 [95% CI = 0.26 to 0.72]). CONCLUSIONS: One in 5 patients with a hip fracture presented with myocardial injury. Accelerated surgery resulted in a lower mortality risk than standard care for these patients; however, these findings need to be confirmed. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Risk Factors for Hospital Readmission Following Noncardiac Surgery: International Cohort Study.

Objective: To determine timing and risk factors associated with readmission within 30 days of discharge following noncardiac surgery. Background: Hospital readmission after noncardiac surgery is costly. Data on the drivers of readmission have largely been derived from single-center studies focused on a single surgical procedure with uncertainty regarding generalizability. Methods: We undertook an international (28 centers, 14 countries) prospective cohort study of a representative sample of adults ≥45 years of age who underwent noncardiac surgery. Risk factors for readmission were assessed using Cox regression (ClinicalTrials.gov, NCT00512109). Results: Of 36,657 eligible participants, 2744 (7.5%; 95% confidence interval [CI], 7.2-7.8) were readmitted within 30 days of discharge. Rates of readmission were highest in the first 7 days after discharge and declined over the follow-up period. Multivariable analyses demonstrated that 9 baseline characteristics (eg, cancer treatment in past 6 months; adjusted hazard ratio [HR], 1.44; 95% CI, 1.30-1.59), 5 baseline laboratory and physical measures (eg, estimated glomerular filtration rate or on dialysis; HR, 1.47; 95% CI, 1.24-1.75), 7 surgery types (eg, general surgery; HR, 1.86; 95% CI, 1.61-2.16), 5 index hospitalization events (eg, stroke; HR, 2.21; 95% CI, 1.24-3.94), and 3 other factors (eg, discharge to nursing home; HR, 1.61; 95% CI, 1.33-1.95) were associated with readmission. Conclusions: Readmission following noncardiac surgery is common (1 in 13 patients). We identified perioperative risk factors associated with 30-day readmission that can help frontline clinicians identify which patients are at the highest risk of readmission and target them for preventive measures.

Barriers and facilitators to perioperative smoking cessation: A scoping review.

OBJECTIVE: Smoking cessation interventions are underutilized in the surgical setting. We aimed to systematically identify the barriers and facilitators to smoking cessation in the surgical setting. METHODS: Following the Joanna Briggs Institute (JBI) framework for scoping reviews, we searched 5 databases (MEDLINE, Embase, Cochrane CENTRAL, CINAHL, and PsycINFO) for quantitative or qualitative studies published in English (since 2000) evaluating barriers and facilitators to perioperative smoking cessation interventions. Data were analyzed using thematic analysis and mapped to the theoretical domains framework (TDF). RESULTS: From 31 studies, we identified 23 unique barriers and 13 facilitators mapped to 11 of the 14 TDF domains. The barriers were within the domains of knowledge (e.g., inadequate knowledge of smoking cessation interventions) in 23 (74.2%) studies; environmental context and resources (e.g., lack of time to deliver smoking cessation interventions) in 19 (61.3%) studies; beliefs about capabilities (e.g., belief that patients are nervous about surgery/diagnosis) in 14 (45.2%) studies; and social/professional role and identity (e.g., surgeons do not believe it is their role to provide smoking cessation interventions) in 8 (25.8%) studies. Facilitators were mainly within the domains of environmental context and resources (e.g., provision of quit smoking advice as routine surgical care) in 15 (48.4%) studies, reinforcement (e.g., surgery itself as a motivator to kickstart quit attempts) in 8 (25.8%) studies, and skills (e.g., smoking cessation training and awareness of guidelines) in 5 (16.2%) studies. CONCLUSION: The identified barriers and facilitators are actionable targets for future studies aimed at translating evidence informed smoking cessation interventions into practice in perioperative settings. More research is needed to evaluate how targeting these barriers and facilitators will impact smoking outcomes.

Comparative benefits and harms of perioperative interventions to prevent chronic pain after orthopedic surgery: a systematic review and network meta-analysis of randomized trials.

BACKGROUND: Chronic postsurgical pain (CPSP) is common following musculoskeletal and orthopedic surgeries and is associated with impairment and reduced quality of life. Several interventions have been proposed to reduce CPSP; however, there remains uncertainty regarding which, if any, are most effective. We will perform a systematic review and network meta-analysis of randomised trials to assess the comparative benefits and harms of perioperative pharmacological and psychological interventions directed at preventing chronic pain after musculoskeletal and orthopedic surgeries. METHODS: We will search MEDLINE, Embase, PsycINFO, CINAHL, and the Cochrane Central Register of Controlled Trials from inception to present, without language restrictions. We will include randomised controlled trials that as follows: (1) enrolled adult patients undergoing musculoskeletal or orthopedic surgeries; (2) randomized them to any pharmacological or psychological interventions, or their combination directed at reducing CPSP, placebo, or usual care; and (3) assessed pain at 3 months or more after surgery. Screening for eligible trials, data extraction, and risk-of-bias assessment using revised Cochrane risk-of-bias tool (RoB 2.0) will be performed in duplicate and independently. Our main outcome of interest will be the proportion of surgical patients reporting any pain at ≥ 3 months after surgery. We will also collect data on other patient important outcomes, including pain severity, physical functioning, emotional functioning, dropout rate due to treatment-related adverse event, and overall dropout rate. We will perform a frequentist random-effects network meta-analysis to determine the relative treatment effects. When possible, the modifying effect of sex, surgery type and duration, anesthesia type, and veteran status on the effectiveness of interventions will be investigated using network meta-regression. We will use the GRADE approach to assess the certainty evidence and categorize interventions from most to least beneficial using GRADE minimally contextualised approach. DISCUSSION: This network meta-analysis will assess the comparative effectiveness of pharmacological and psychological interventions directed at preventing CPSP after orthopedic surgery. Our findings will inform clinical decision-making and identify promising interventions for future research. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42023432503.

One-year Outcomes after Discharge from Noncardiac Surgery and Association between Predischarge Complications and Death after Discharge: Analysis of the VISION Prospective Cohort Study.

BACKGROUND: In previous analyses, myocardial injury after noncardiac surgery, major bleeding, and sepsis were independently associated with most deaths in the 30 days after noncardiac surgery, but most of these deaths occurred during the index hospitalization for surgery. The authors set out to describe outcomes after discharge from hospital up to 1 yr after inpatient noncardiac surgery and associations between predischarge complications and postdischarge death up to 1 yr after surgery. METHODS: This study was an analysis of patients discharged after inpatient noncardiac surgery in a large international prospective cohort study across 28 centers from 2007 to 2013 of patients aged 45 yr or older followed to 1 yr after surgery. The study estimated (1) the cumulative postdischarge incidence of death and other outcomes up to a year after surgery and (2) the adjusted time-varying associations between postdischarge death and predischarge complications including myocardial injury after noncardiac surgery, major bleeding, sepsis, infection without sepsis, stroke, congestive heart failure, clinically important atrial fibrillation or flutter, amputation, venous thromboembolism, and acute kidney injury managed with dialysis. RESULTS: Among 38,898 patients discharged after surgery, the cumulative 1-yr incidence was 5.8% (95% CI, 5.5 to 6.0%) for all-cause death and 24.7% (95% CI, 24.2 to 25.1%) for all-cause hospital readmission. Predischarge complications were associated with 33.7% (95% CI, 27.2 to 40.2%) of deaths up to 30 days after discharge and 15.0% (95% CI, 12.0 to 17.9%) up to 1 yr. Most of the association with death was due to myocardial injury after noncardiac surgery (15.6% [95% CI, 9.3 to 21.9%] of deaths within 30 days, 6.4% [95% CI, 4.1 to 8.7%] within 1 yr), major bleeding (15.0% [95% CI, 8.3 to 21.7%] within 30 days, 4.7% [95% CI, 2.2 to 7.2%] within 1 yr), and sepsis (5.4% [95% CI, 2.2 to 8.6%] within 30 days, 2.1% [95% CI, 1.0 to 3.1%] within 1 yr). CONCLUSIONS: One in 18 patients 45 yr old or older discharged after inpatient noncardiac surgery died within 1 yr, and one quarter were readmitted to the hospital. The risk of death associated with predischarge perioperative complications persists for weeks to months after discharge.

Landiolol for the prevention of postoperative atrial fibrillation after cardiac surgery: a systematic review and meta-analysis.

PURPOSE: Postoperative atrial fibrillation (POAF) is a common complication following cardiac surgery. Although the evidence suggests that beta blockers prevent POAF, they often cause hypotension. Landiolol, an ultra-short-acting ß1 blocker, may prevent POAF, without adverse hemodynamic consequences. SOURCE: We searched MEDLINE, CENTRAL, Embase, and trial registries between January 1970 and March 2022. We included randomized controlled trials (RCTs) that evaluated the effect of landiolol for the prevention of POAF after cardiac surgery. Two reviewers independently assessed eligibility, extracted data, and assessed risk of bias using the Risk of Bias 2.0 tool. We pooled data using random-effects models. We used the Grading of Recommendations, Assessment, Development and Evaluations framework to assess certainty of evidence. PRINCIPAL FINDINGS: Nine RCTs including 868 participants met the eligibility criteria. Patients randomized to landiolol (56/460) had less POAF compared with controls (133/408) with a relative risk (RR) of 0.40 (95% confidence interval [CI], 0.30 to 0.54; I2 = 0%;) and an absolute risk of 12.2% vs 32.6% (absolute risk difference, 20.4%; 95% CI, 15.0 to 25.0). Landiolol resulted in a shorter hospital length-of-stay (LOS) (268 patients; mean difference, -2.32 days; 95% CI, -4.02 to -0.57; I2 = 0%). We found no significant difference in bradycardia (RR, 1.11; 95% CI, 0.48 to 2.56; I2 = 0%). No hypotension was reported with landiolol. We judged the certainty of evidence as moderate for POAF (because of indirectness as outcomes were not clearly defined) and low for LOS (because of imprecision and concern of reporting bias). CONCLUSION: In patients undergoing cardiac surgery, landiolol likely reduces POAF and may reduce LOS. A definitive large RCT is needed to confirm these findings. STUDY REGISTRATION: PROSPERO (CRD42021262703); registered 25 July 2021.

RéSUMé: OBJECTIF: La fibrillation auriculaire postopératoire (FAPO) est une complication fréquente après une chirurgie cardiaque. Bien que les données probantes suggèrent que les bêta-bloqueurs préviennent la FAPO, ces agents provoquent souvent une hypotension. Le landiolol, un ß1-bloqueur à action ultra-courte, pourrait prévenir la FAPO sans conséquences hémodynamiques indésirables. SOURCES: Nous avons effectué des recherches dans les bases de données MEDLINE, CENTRAL et Embase, et dans les registres d'études publiées entre janvier 1970 et mars 2022. Nous avons inclus les études randomisées contrôlées (ERC) évaluant l'effet du landiolol pour la prévention de la FAPO après une chirurgie cardiaque. Deux personnes ont indépendamment révisé l'éligibilité, extrait les données et évalué le risque de biais à l'aide de l'outil Risque de biais 2.0. Nous avons regroupé les données à l'aide de modèles à effets aléatoires. Nous avons utilisé le système de notation GRADE (Grading of Recommendations Assessment, Development, and Evaluation) pour évaluer la certitude des données probantes. CONSTATATIONS PRINCIPALES: Neuf ERC incluant 868 personnes remplissaient les critères d'éligibilité. Les patient·es randomisé·es dans le groupe landiolol (56/460) présentaient moins de FAPO que les témoins (133/408), avec un risque relatif (RR) de 0,40 (intervalle de confiance [IC] à 95 %, 0,30 à 0,54; I2 = 0 %) et un risque absolu de 12,2 % vs 32,6 % (différence de risque absolue, 20,4 %; IC 95 % 95 %, 15,0 à 25,0). Le landiolol a entraîné une durée de séjour hospitalier plus courte (268 patient·es; différence moyenne, −2,32 jours; IC 95 %, −4,02 à −0,57; I2 = 0 %). Nous n'avons trouvé aucune différence significative en matière de bradycardie (RR, 1,11; IC 95 %, 0,48 à 2,56; I2 = 0 %). Aucune hypotension n'a été rapportée avec le landiolol. Nous avons jugé que la certitude des données probantes était modérée pour la FAPO (en raison du caractère indirect car les critères d'évaluation n'étaient pas clairement définis) et faible pour la durée de séjour hospitalier (en raison de l'imprécision et de questionnements concernant le biais de déclaration). CONCLUSION: Chez les patient·es bénéficiant d'une chirurgie cardiaque, le landiolol réduit probablement la FAPO et peut réduire la durée de séjour hospitalier. Une ERC définitive à grande échelle est nécessaire pour confirmer ces résultats. ENREGISTREMENT DE L'éTUDE: PROSPERO (CRD42021262703); enregistrée le 25 juillet 2021.

Prevention of perioperative stroke in patients undergoing non-cardiac surgery.

About 300 million adults undergo non-cardiac surgery annually. Although, in this setting, the incidence of perioperative stroke is low, the absolute number of patients experiencing a stroke is substantial. Furthermore, most patients with this complication will die or end up with severe disability. Covert brain infarctions are more frequent than overt strokes and are associated with postoperative delirium, cognitive decline, and cerebrovascular events at 1 year after surgery. Evidence shows that traditional stroke risk factors including older age, hypertension, and atrial fibrillation are also associated with perioperative stroke; previous stroke is the strongest risk factor for perioperative stroke. Increasing evidence also suggests the pathogenic role of perioperative events, such as hypotension, new atrial fibrillation, paradoxical embolism, and bleeding. Clinicians involved in perioperative care should be aware of this evidence on prevention strategies to improve patient outcomes after non-cardiac surgery.

Frequency of postoperative cognitive dysfunction after non-cardiac surgery and its impact on functional outcomes: protocol for a systematic review.

INTRODUCTION: Older surgical candidates are at increased risk of a phenomenon known as postoperative cognitive dysfunction (POCD). Several studies have looked at the incidence of POCD at different time points following surgery, using different study methods. Fewer have assessed whether changes in cognition after surgery are attributable to surgery and how they impact patient function and quality of life. The aim of this systematic review is to summarise and appraise studies addressing any of the following research questions (RQs): (RQ1) what is the frequency of POCD after non-cardiac surgery?; (RQ2) is non-cardiac surgery associated with an increased risk of cognitive decline?; (RQ3) is POCD after non-cardiac surgery associated with patient-important outcomes? METHODS AND ANALYSIS: This protocol adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols guidelines. Three electronic databases (MEDLINE, PsycINFO and EMBASE) will be systematically searched from their inception date. Identified studies will be screened by two reviewers for eligibility using Covidence, and data will be extracted into a standardised electronic form. We will evaluate methodological quality of included studies using the Quality In Prognosis Studies and its adaptation to the overall prognosis question, and the CLARITY risk of bias for cohort and case-control studies. For RQ1, we will estimate an average POCD frequency at different time points by performing a meta-analysis of included studies when appropriate. For RQ2 and RQ3, we will extract and meta-analyse the effect measures for the association of surgery with cognitive decline when compared with the non-surgical comparator, and association of cognitive changes with functional changes, quality of life and other patient-important outcomes based on available evidence. We will narratively summarise and discuss the different methods implemented in the existing studies to answer the three RQs, and when meta-analysis is deemed infeasible, we will qualitatively report the results of the included studies. ETHICS AND DISSEMINATION: This project involves the collection and analysis of data from previously published studies and therefore does not require ethics approval. We plan to present the findings of this research project at peer-reviewed conferences and publish the results in peer-reviewed journals. PROSPERO REGISTRATION NUMBER: CRD42022370674.

Preoperative assessment of postoperative delirium: a cross-sectional study of patients and anesthesiologists in Canada.

PURPOSE: We sought to evaluate 1) patient- and anesthesiologist-reported rates of postoperative delirium (POD) risk discussion during preoperative meetings, 2) patients' and anesthesiologists' ratings of the importance of POD, and 3) predictors of patient-reported discussion of POD risk during preoperative meetings. METHODS: In this multicentre two-part cross-sectional survey study, patients ≥ 65 yr scheduled to undergo elective noncardiac surgery completed a five-minute survey after preoperative anesthesia consultation. Patients were asked about their perception of POD importance, and whether they discussed or were assessed for POD risk. Anesthesiologists were surveyed using self-administered surveys circulated via institutional email lists. Anesthesiologists were asked about the frequency of POD risk assessment and discussion in older adults, tools used, and perception of POD-screening barriers. RESULTS: Four hundred and twelve (of 510 approached) patients (50% male; mean age, 73 yr) and 267 anesthesiologists (of 1,205 invited via e-mail) participated in this study conducted in five Canadian hospitals. Postoperative delirium screening and discussion was reported by 88/412 (22%) patients and 229/267 (86%) anesthesiologists. Postoperative delirium was rated as "somewhat-extremely" important by 64% of patients. A previous history of delirium, higher education, the number of daily medications, and longer surgical duration were associated with POD discussion. On average, anesthesiologists rated the importance of POD at 8/10, and 42% ranked "patient risk factors" as the top reason prompting discussion. CONCLUSION: The combined evaluation of patients' and anesthesiologists' perspectives provides valuable information on preoperative POD screening and risk assessment, and highlights areas for improvement in the current practice. Most factors we identified to be associated with higher odds of POD discussion are recognized risk factors of POD.

RéSUMé: OBJECTIF: Nous avons cherché à évaluer 1) les taux de discussion concernant le risque de delirium postopératoire (DPO) déclarés par les patient·es et les anesthésiologistes lors des rencontres préopératoires, 2) les évaluations des patient·es et des anesthésiologistes de l'importance de DPO, et 3) les prédicteurs d'une discussion telle que rapportée par les patient·es sur le risque de DPO pendant les rencontres préopératoires. MéTHODE: Dans ce sondage transversal multicentrique en deux parties, les patient·es ≥ 65 ans devant subir une chirurgie non cardiaque non urgente ont rempli un sondage de cinq minutes après la consultation d'anesthésie préopératoire. Les patient·es ont été interrogé·es sur leur perception de l'importance du DPO et si leur risque de DPO avait été discuté ou évalué. Des sondages auto-administrés ont été distribués aux anesthésiologistes via les listes de courriels institutionnelles. Ce sondage interrogeait les anesthésiologistes quant à la fréquence de l'évaluation et de la discussion des risques de DPO chez les personnes âgées, aux outils utilisés et à la perception des obstacles au dépistage de DPO. RéSULTATS: Quatre cent douze (des 510 personnes approchées) patient·es (50 % d'hommes; âge moyen, 73 ans) et 267 anesthésiologistes (sur 1205 invité·es par courriel) ont participé à cette étude menée dans cinq hôpitaux canadiens. Le dépistage et la discussion sur le delirium postopératoire ont été signalés par 88/412 (22 %) des patient·es et 229/267 (86 %) des anesthésiologistes. Le delirium postopératoire a été jugé « assez ­ extrêmement ¼ important par 64 % des patient·es. Des antécédents de delirium, des études supérieures, le nombre de médicaments quotidiens et une durée chirurgicale plus longue ont été associés à la discussion sur le DPO. En moyenne, les anesthésiologistes ont évalué l'importance du DPO à 8/10, et 42 % ont classé les « facteurs de risque liés au/à la patient·e ¼ comme la principale raison suscitant la discussion. CONCLUSION: L'évaluation combinée des points de vue des patient·es et des anesthésiologistes fournit des informations précieuses sur le dépistage préopératoire des DPO et l'évaluation des risques, et met en évidence les domaines à améliorer dans la pratique actuelle. La plupart des facteurs que nous avons identifiés comme étant associés à des probabilités plus élevées de discussion sur le DPO sont des facteurs de risque reconnus de DPO.

Noninferiority margins exceed superiority effect estimates for mortality in cardiovascular trials in high-impact journals.

OBJECTIVES: To determine, in a sample of noninferiority trials, the noninferiority margins (NIMs) and their relation to effect estimates in superiority trials, the rationale being that in general NIMs should be no larger than effects declared important in superiority trials. STUDY DESIGN AND SETTING: To identify cardiovascular trials published in high-impact journals with a statistically significant primary outcome involving mortality, we systematically searched PubMed, Embase, and MEDLINE databases (January 2015-July 2020). We documented the NIMs and determined the proportion of trials with NIMs larger than the median effect estimates across superiority trials. RESULTS: From 1,477 screened titles, 65 (39 noninferiority, 26 superiority) trials proved eligible. The NIMs ranged from risk difference of 0.54-10%. The effect estimate across superiority trials was a median risk difference of 2.1% (interquartile range 1.5-4.9); the NIM was larger than 2.1% in 28 (71.8%) noninferiority trials and larger than 1.5%, which was the lower bound of the interquartile range in 32 (82.1%) noninferiority trials. CONCLUSION: The very wide range of noninferiority margins and the proportion above a threshold that most would consider an important mortality reduction suggest that clinicians and guideline panels should focus on study results, paying little attention to authors' noninferiority margins.

Hypotension-Avoidance Versus Hypertension-Avoidance Strategies in Noncardiac Surgery : An International Randomized Controlled Trial.

BACKGROUND: Among patients having noncardiac surgery, perioperative hemodynamic abnormalities are associated with vascular complications. Uncertainty remains about what intraoperative blood pressure to target and how to manage long-term antihypertensive medications perioperatively. OBJECTIVE: To compare the effects of a hypotension-avoidance and a hypertension-avoidance strategy on major vascular complications after noncardiac surgery. DESIGN: Partial factorial randomized trial of 2 perioperative blood pressure management strategies (reported here) and tranexamic acid versus placebo. (ClinicalTrials.gov: NCT03505723). SETTING: 110 hospitals in 22 countries. PATIENTS: 7490 patients having noncardiac surgery who were at risk for vascular complications and were receiving 1 or more long-term antihypertensive medications. INTERVENTION: In the hypotension-avoidance strategy group, the intraoperative mean arterial pressure target was 80 mm Hg or greater; before and for 2 days after surgery, renin-angiotensin-aldosterone system inhibitors were withheld and the other long-term antihypertensive medications were administered only for systolic blood pressures 130 mm Hg or greater, following an algorithm. In the hypertension-avoidance strategy group, the intraoperative mean arterial pressure target was 60 mm Hg or greater; all antihypertensive medications were continued before and after surgery. MEASUREMENTS: The primary outcome was a composite of vascular death and nonfatal myocardial injury after noncardiac surgery, stroke, and cardiac arrest at 30 days. Outcome adjudicators were masked to treatment assignment. RESULTS: The primary outcome occurred in 520 of 3742 patients (13.9%) in the hypotension-avoidance group and in 524 of 3748 patients (14.0%) in the hypertension-avoidance group (hazard ratio, 0.99 [95% CI, 0.88 to 1.12]; P = 0.92). Results were consistent for patients who used 1 or more than 1 antihypertensive medication in the long term. LIMITATION: Adherence to the assigned strategies was suboptimal; however, results were consistent across different adherence levels. CONCLUSION: In patients having noncardiac surgery, our hypotension-avoidance and hypertension-avoidance strategies resulted in a similar incidence of major vascular complications. PRIMARY FUNDING SOURCE: Canadian Institutes of Health Research, National Health and Medical Research Council (Australia), and Research Grant Council of Hong Kong.

High-sensitivity Troponin I Predicts Major Cardiovascular Events after Non-Cardiac Surgery: A Vascular Events in Non-Cardiac Surgery Patients Cohort Evaluation (VISION) Substudy.

BACKGROUND: Myocardial injury after non-cardiac surgery (MINS), based on measurement of troponin T, is associated with perioperative major adverse cardiovascular events (MACE). We therefore determined the high-sensitivity troponin I (hsTnI) thresholds associated with 30 day MACE after non-cardiac surgery. METHODS: We performed a nested biobank cohort study of 4553 patients from the Vascular Events in Non-Cardiac Surgery Patients Cohort Evaluation (VISION) Study. We measured hsTnI (ADVIA Centaur® hsTnI assay) on postoperative days 1 to 3 in patients ≥45 years undergoing non-cardiac surgery. An iterative Cox proportional hazard model determined peak postoperative hsTnI thresholds independently associated with MACE (i.e., death, myocardial infarction occurring on postoperative day 4 or after, non-fatal cardiac arrest, or congestive heart failure) within 30 days after surgery. RESULTS: MACE occurred in 89/4545 (2.0%) patients. Peak hsTnI values of <75 ng/L, 75 ng/L to <1000 ng/L, and ≥1000 ng/L were associated with 1.2% (95% CI, 0.9-1.6), 7.1% (95% CI, 4.8-10.5), and 25.9% (95% CI, 16.3-38.4) MACE, respectively. Compared to peak hsTnI <75 ng/L, values 75 ng/L to <1000 ng/L and ≥1000 ng/L were associated with adjusted hazard ratios (aHR) of 4.53 (95% CI, 2.75-7.48) and 16.17 (95% CI, 8.70-30.07), respectively. MACE was observed in 9% of patients with peak hsTnI ≥75 ng/L vs 1% in patients with peak hsTnI <75 ng/L (aHR 5.76; 95% CI, 3.64-9.11). A peak hsTnI ≥75 ng/L was associated with MACE in the presence (aHR 9.35; 95% CI, 5.28-16.55) or absence (aHR 3.99; 95% CI, 2.19-7.25) of ischemic features of myocardial injury. CONCLUSION: A peak postoperative hsTnI ≥75 ng/L was associated with >5-fold increase in the risk of 30 days MACE compared to levels <75 ng/L. This threshold could be used for MINS diagnosis when the ADVIA Centaur hsTnI assay is used.Clinicaltrials.gov Registration Number: NCT00512109.

Pulmonary hypertension and associated outcomes in noncardiac surgery: A systematic review and meta-analysis.

BACKGROUND: Some studies suggest that patients with pulmonary hypertension (PH) may be at higher risk of complications and death after noncardiac surgery. However, the magnitude of these associations is unclear. OBJECTIVES: To determine the associations between PH and adverse outcomes after noncardiac surgery. METHODS: We searched PUBMED and EMBASE for studies published from January 1970 to April 2022. We included studies that reported the association between PH and one or more outcomes of interest occurring after noncardiac surgery. Data were pooled using random-effects models and reported as summary odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: Eighteen studies met eligibility criteria (n=18,214,760). PH was independently associated with mortality (adjusted odds ratio [OR] 2.09; 95% CI, 1.51-2.90; I2=98%; 8 studies). PH was associated with a higher unadjusted risk of deep venous thrombosis (OR 4.02; 95% CI, 2.14-7.54; I2=85%; 3 studies), pulmonary embolism (OR 4.16; 95% CI, 3.23-5.36; I2=69%; 7 studies), myocardial infarction (OR 1.49; 95% CI, 1.44-1.54; I2=0%; 5 studies), congestive heart failure or cardiogenic shock (OR 3.37; 95% CI, 1.73-6.60; I2=34%; 5 studies), length of hospital stay (mean difference 1.97 days; 95% CI, 0.81-3.12; I2=99%; 5 studies), and delayed extubation (OR 5.98; 95% CI, 1.70-21.02; I2=3%; 3 studies). PH was associated with lower unadjusted risk of postoperative stroke (OR 0.93; 95% CI, 0.88-0.98; I2=0%; 3 studies). CONCLUSION: PH is a predictor of morbidity and mortality after noncardiac surgery. High quality studies are needed to determine effective strategies for reducing postoperative complications in this population.

Postoperative pain and pain management and neurocognitive outcomes after non-cardiac surgery: a protocol for a series of systematic reviews.

BACKGROUND: Postoperative delirium (POD) is common after non-cardiac surgery in older adults and can result in increased risk of adverse outcomes including postoperative cognitive dysfunction (POCD). Pain after surgery is also frequent and can persist as chronic postsurgical pain (CPSP). Evidence is inconsistent and controversial on whether acute and chronic postsurgical pain, and different postoperative pain management strategies (including opioid versus opioid-sparing strategies), is associated with the occurrence of POD and POCD. In this protocol, we propose a series of systematic reviews to answer the following research questions: In adults undergoing non-cardiac surgery, (1) is acute postsurgical pain associated with POD and/or POCD? (2) Are opioid-sparing/avoidance strategies of acute postoperative pain management associated with lower incidence and/or severity of POD and POCD, compared to predominantly opioid-based strategies? (3) Is CPSP associated with POCD? (4) Are opioid-sparing management strategies of CPSP associated with lower incidence and/or severity of POCD compared to standard of care or strategies not aiming at reduced opioid use? METHODS: We will search MEDLINE, EMBASE, Cochrane (CENTRAL), CINAHL, and PSYCHINFO. According to the research question, we will include cohort and case-control studies (questions 1 and 3) or randomized controlled trials and non-randomized studies (questions 2 and 4). The risk of bias will be assessed independently and in duplicate using the revised Cochrane risk-of-bias tool, the Newcastle-Ottawa Scale, and the Joanna-Briggs Institute critical appraisal checklist. Disagreements will be resolved by a third reviewer. Findings will be reported narratively, and where possible and appropriate, meta-analyses will be performed. Certainty of evidence will be assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach. We will conduct the reviews in accordance with the guideline of the Preferred Reporting Items for Systematic Review and Meta-Analyses Protocols. DISCUSSION: Our systematic reviews will summarize available evidence to date on the association of postoperative pain and its management strategies with the incidence of POD and POCD in non-cardiac surgery. We will evaluate the existing evidence and its limitations and inform the design of future interventional studies comparing the effects of different pain management strategies on postoperative neurocognitive outcomes. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42021192105.