The value of routine preoperative electrocardiography in predicting myocardial infarction after noncardiac surgery

Artificial intelligence-enhanced electrocardiography improves the detection of coronary artery disease

An AI-assisted algorithm has been developed to improve the detection of significant coronary artery disease (CAD) in high-risk individuals who have normal electrocardiograms (ECGs). This retrospective study analyzed ECGs from patients aged ≥ 18 years who were undergoing coronary angiography to obtain a clinical diagnosis at Chang Gung Memorial Hospital in Taiwan. Utilizing 12-lead ECG datasets, the algorithm integrated features like time intervals, amplitudes, and slope between peaks, a total of 561 features, with the XGBoost model yielding the best performance. The AI-enhanced ECG algorithm demonstrated high sensitivity (0.82-0.84) when detecting CAD in patients with normal ECGs and gave remarkably high prediction rates among those with abnormal ECGs, both with and without ischemia (92 %-95 % and 80 %-83 %, respectively). Notably, the algorithm's top features, mostly related to slope and amplitude differences, are challenging for clinicians to discern manually. Additionally, the study highlights significant sex differences regarding feature prediction and ranking. Comparatively, the AI-enhanced ECG's detection capability matched that of myocardial perfusion scintigraphy, which is a costly nuclear medicine test, and offers a more accessible alternative for identifying significant CAD, especially among patients with atypical ECG readings.

2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery" provides recommendations to guide clinicians in the perioperative cardiovascular evaluation and management of adult patients undergoing noncardiac surgery.

METHODS

A comprehensive literature search was conducted from August 2022 to March 2023 to identify clinical studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

Recommendations from the "2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery" have been updated with new evidence consolidated to guide clinicians; clinicians should be advised this guideline supersedes the previously published 2014 guideline. In addition, evidence-based management strategies, including pharmacological therapies, perioperative monitoring, and devices, for cardiovascular disease and associated medical conditions, have been developed.

2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery" provides recommendations to guide clinicians in the perioperative cardiovascular evaluation and management of adult patients undergoing noncardiac surgery.

METHODS

A comprehensive literature search was conducted from August 2022 to March 2023 to identify clinical studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

Recommendations from the "2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery" have been updated with new evidence consolidated to guide clinicians; clinicians should be advised this guideline supersedes the previously published 2014 guideline. In addition, evidence-based management strategies, including pharmacological therapies, perioperative monitoring, and devices, for cardiovascular disease and associated medical conditions, have been developed.

Preoperative Testing

Preoperative medical evaluation can minimize inefficiencies and improve outcomes. Thoughtful use of preoperative testing can aid in that effort, but, conversely, indiscriminate testing can detract from it. The United Kingdom National Institute for Health Care and Excellence, European Society of Anaesthesiology, and American Society of Anesthesiologists (ASA) have all stated that routine preoperative testing is not supported by evidence. Testing is supported only when clinical indications are present. Particularly in low-risk patients, such as those with an ASA classification of 1 or 2 who are undergoing ambulatory procedures, evidence suggests that preoperative testing fails to reduce the risk of complications.

The role of routine cardiac investigations before hyperbaric oxygen treatment

Cardiac complications are a rare but potentially serious consequence of hyperbaric oxygen treatment (HBOT), resulting from increased blood pressure and decreased heart rate and cardiac output associated with treatment. These physiologic changes are generally well-tolerated by patients without preexisting cardiac conditions, although those with known or undetected cardiac disease may be more vulnerable to treatment complications. Currently, there are no universally accepted guidelines for pre-HBOT cardiac screening to identify these patients at heightened risk, leading to variability in practice patterns. In the absence of HBOT-specific evidence, screening protocols might be adapted from the diving medicine community; however, given the important differences in physiological stressors, these may not be entirely applicable to patients undergoing HBOT. Traditional cardiac investigations such as electro- and echo-cardiograms are limited in their ability to detect relevant risk modifying states in the pre-HBOT patient, stymieing their cost-effectiveness as routine tests. In the absence of strong evidence to support routine cardiac investigation, we argue that a comprehensive history and physical exam - tailored to identify high-risk patients based on clinical parameters - may serve as a more practical screening tool. While certain unique patient groups such as those undergoing dialysis or with implanted cardiac devices may warrant specialised assessment, thorough evaluation may be sufficient to identify many patients unlikely to benefit from cardiac investigation in the pre-HBOT setting. A clinical decision-making tool based on suggested low-risk and high-risk features is offered to guide the use of targeted cardiac investigation prior to HBOT.

Magnitude and associated factors of intraoperative cardiac complications among geriatric patients who undergo non-cardiac surgery at public hospitals in the southern region of Ethiopia: a multi-center cross-sectional study in 2022/2023

Background

Intraoperative cardiac complications are a common cause of morbidity and mortality in non-cardiac surgery. The risk of these complications increased with the average age increasing from 65. In a resource-limited setting, including our study area, the magnitude and associated factors of intraoperative cardiac complications have not been adequately investigated. The aim of this study was to assess the magnitude and associated factors of intraoperative cardiac complications among geriatric patients undergoing non-cardiac surgery.

Methods

An institutional-based multi-center cross-sectional study was conducted on 304 geriatric patients at governmental hospitals in the southern region of Ethiopia, from 20 March 2022 to 25 August 2022. Data were collected by chart review and patient interviews. Epi Data version 4.6 and SPSS version 25 were used for analysis. The variables that had association (p < 0.25) were considered for multivariable logistic regression. A p value < 0.05 was considered significant for association.

Result

The overall prevalence of intraoperative cardiac complications was 24.3%. Preoperative ST-segment elevation adjusted odds ratio (AOR = 2.43, CI =2.06-3.67), history of hypertension (AOR = 3.42, CI =2.02-6.08), intraoperative hypoxia (AOR = 3.5, CI = 2.07-6.23), intraoperative hypotension (AOR = 6.2 9, CI =3.51-10.94), age > 85 years (AOR = 6.01, CI = 5.12-12.21), and anesthesia time > 3 h (AOR =2.27, CI = 2.0.2-18.25) were factors significantly associated with intraoperative cardiac complications.

Conclusion

The magnitude of intraoperative cardiac complications was high among geriatric patients who had undergone non-cardiac surgery. The independent risk factors of intraoperative cardiac complications for this population included age > 85, ST-segment elevation, perioperative hypertension (stage 3 with regular treatment), duration of anesthesia >3 h, intraoperative hypoxia, and intraoperative hypotension. Holistic preoperative evaluation, optimization optimal and perioperative care for preventing perioperative risk factors listed above, and knowing all possible risk factors are suggested to reduce the occurrence of complications.

Preoperative ECG Abnormalities Among Patients Who Underwent Elective Surgical Operations at the Kuwaiti Specialised Hospital, Khartoum, Sudan: A Cross-Sectional Study

BACKGROUND

The presence of preoperative ECG abnormalities has shown wide variation, and its value has been argued; thus, this study aimed to determine preoperative ECG abnormalities among Sudanese patients and their correlates.

MATERIALS AND METHODS

An observational descriptive cross-sectional study was conducted at the Kuwaiti Specialised Hospital, Khartoum, Sudan, from October 2020 to March 2021, including all patients over 40 years of age who planned to undergo elective surgery. Demographic, clinical, and ECG findings were obtained during the pre-anaesthesia check-up. The data were analysed using IBM SPSS software version 28 (IBM Corp., Armonk, NY).

RESULTS

The study included a total of 304 patients with a mean age of 60±14 years, a male predominance of 210 (69.1%) patients, the presence of hypertension (HTN) in 65 (21.4%), and diabetes mellitus (DM) in 58 (19.1%) patients. The study showed that 235 (77%) patients had at least one ECG abnormality. However, 62 (20.4%) were diagnosed as having normal ECG variations; the most commonly diagnosed abnormality was ischemic heart disease (IHD) (32.5%), followed by sinus tachycardia (39, 12.8%). The QRS complex abnormalities were the most common (100, 32.9%), with M-shaped QRS (RSR pattern) being the most common single ECG abnormal sign (65, 21.4%). The ECG abnormalities showed no significant association with age (p-value = 0.24), gender (p-value = 0.16), DM (p-value = 0.77), HTN (p-value = 0.35), asthma (p-value = 0.35), or the grade of surgery (p-value = 0.52). However, the diagnosis of IHD was associated with the presence of HTN (p-value = 0.001).

CONCLUSION

Incidental preoperative ECG abnormalities are common among Sudanese patients undergoing elective surgery, affecting more than three-quarters of them and being of diagnostic value as they led to the diagnosis of ischemic heart disease in nearly one-third of patients. Hypertensive patients may benefit from routine preoperative ECG testing, as ECG signs of ischemic heart disease are more common among hypertensive patients.

New-Onset Intermittent Deceleration-Dependent Left Bundle Branch Block Following Induction of General Anesthesia in a Healthy Patient: A Case Report

This case report aims to highlight an atypical presentation of deceleration-dependent aberrancy (DDA) following the induction of general anesthesia in a patient with no known cardiac history. It emphasizes the critical role of intraoperative monitoring and the potential effects of anesthetic agents on the cardiac conduction system. A 46-year-old Hispanic male with no significant past medical or surgical history presented for surgical repair of a comminuted radial fracture. Following anesthesia induction with propofol, midazolam, and fentanyl, he developed a transient left bundle branch block (LBBB) exhibiting deceleration-dependent characteristics. Despite stable hemodynamics, the LBBB pattern appeared at heart rates below 60 beats per minute and resolved with heart rates above 90 beats per minute. This was managed intraoperatively with glycopyrrolate. Postoperative evaluations, including a 12-lead ECG, echocardiogram, and nuclear stress test, indicated normal biventricular function with a small to moderate reversible perfusion defect. The patient did not report cardiac symptoms postoperatively and did not prefer to undergo a coronary angiogram. This report underscores the importance of recognizing rate-dependent LBBB as a potential intraoperative complication, even in patients without pre-existing cardiac conditions. The transient nature of DDA, influenced by anesthetic agents and managed through careful monitoring and pharmacological intervention, highlights the necessity for vigilance in perioperative settings. This case contributes to a growing body of evidence suggesting that anesthetic management may require tailored approaches for patients experiencing or at risk for conduction abnormalities. This case illustrates the complexities of cardiac conduction disturbances such as DDA in the context of general anesthesia, serving as a reminder of the importance of thorough monitoring and the judicious use of rate-modifying drugs. It fosters a deeper understanding of the interaction between anesthesia and cardiac electrophysiology. Further research is needed to explore the mechanisms and management strategies for anesthetic-related cardiac conduction abnormalities.

Prognostic Value of Preoperative Electrocardiogram in Low-Risk Patients Undergoing Surgical Intervention and General Anesthesia

BACKGROUND

Patients aged over 50 years require four times more surgical interventions than younger groups. Many guidelines recommend the performance of preoperative electrocardiogram (ECG) in this population.

OBJECTIVES

To determine the value of preoperative ECG in patients aged over 50 years and classified as ASA I-II (surgical risk).

METHODS

Patients older than 50 years, without comorbidities, who underwent surgical intervention and general anesthesia were included in the study. Patients were randomized to undergo ECG (group A, n=214) or not (group B, n=213) in the preoperative period. The following variables were analyzed: sex, age, ECG, chest x-ray and laboratory tests results, surgical risk, surgery duration, adverse events and in-hospital mortality. The level of significance was set at 5%.

RESULTS

Adverse outcomes were reported in 23 (5.4%) patients, with a significant number of adverse events in male patients (OR=7.91 95%CI 3.3-18.90, p<0.001) and in those undergoing major surgeries (OR=30.02 95%CI 4.01-224.92, p<0.001). No differences were observed between patients who underwent ECG and those who did not (OR=1.59, 95%CI, 0.67-3.75, p=0.289). No significant differences were found in the other variables. In multivariate logistic regression, male sex (OR = 6.49; 95%CI 2.42-17.42, p<0.001) and major surgery (OR=22.62; 95%CI 2.95-173.41, p=0.002) were independent predictors of adverse outcomes, whereas undergoing (or not) ECG (OR=1.09; IC95% 0.41-2.90, p=0.867) remained without statistical significance.

CONCLUSION

Our findings suggest that preoperative ECG could not predict an increased risk of adverse outcomes in our study population during the hospital phase.

Association between pre-operative prolonged corrected QT interval and all-cause mortality after non-cardiac surgery

BACKGROUND

Prolonged corrected QT interval (QTc) has been linked to risk of arrhythmias and mortality in the general population. Pre-operative electrocardiography is often obtained for patient-and procedural cardiovascular risk assessment. The aim of this study was to investigate the association of pre-operative QTc and all-cause mortality in a non-cardiac surgical cohort.

METHODS

A retrospective study of all patients over 18 years undergoing non-cardiac surgery at Landspitali-the National University Hospital in Iceland between 2 January 2005 to 31 December 2015, with follow-up through 20 May 2016. Patients were separated into five categories according to their pre-operative QTc interval ≤ 379, 380-439 (reference group), 440-479, 480-519 and ≥520 ms. Primary outcome was long-term mortality and secondary outcome was 30-day mortality.

RESULTS

A total of 10,209 surgeries for 10,209 individuals were included. The median follow-up for mortality was 2691 days (interquartile range [IQR] 1620-3705 days). Patients with longer QTc interval had a higher comorbidity burden, were more likely to undergo emergency surgery and were often prescribed cardiac medications. After adjustment for confounding variables, the hazard ratio (HR) for long-term mortality compared with reference (QTc 380-439 ms) was 0.85 [CI: 0.66-1.09] for QTc ≤379, 1.08 [CI: 0.99-1.17] for QTc 440-479 ms, 1.26 [CI: 1.10-1.43] for QTc between 480 and 519 ms and 0.97 [CI: 0.78-1.21] for QTc ≥520 ms. When compared with reference, only patients with QTc interval between 480 and 519 ms had higher odds ratio for 30-day mortality as odds ratio for other groups were following; 1.12 [CI: 0.18-3.8] for ≤379 ms, 1.03 [CI: 0.70-1.51] for QTc 440-479 ms, 1.64 [CI: 1.02-2.60] for QTc 480-519 ms and 0.98 [0.44-2.06] for QTc ≥520 ms.

CONCLUSION

Pre-operative QTc between 480 and 519 ms is associated with both higher long-term and 30-day mortality after non-cardiac surgery. The results suggest that this could reflect an underlying cardiovascular risk.

Point-of-care ultrasound use in emergencies: what every anaesthetist should know

Point-of-care ultrasound has been embraced by anaesthetists as an invaluable tool for rapid diagnosis of haemodynamic instability, to ensure procedural safety and monitor response to treatments. Increasingly available, affordable and portable, with emerging evidence of improved patient outcomes, point-of-care ultrasound has become a valuable tool in the emergency setting. This state-of-the-art review describes the feasibility of point-of-care ultrasound practice, training and maintenance of competence. It also describes the many uses of point-of-care ultrasound for the anaesthetist and describes the most salient point-of-care ultrasound views for anaesthetic emergencies including: undifferentiated shock; hypoxemia; and trauma. Procedural safety is also discussed in addition to relevant important governance aspects. Cardiac function should be assessed using the parasternal long axis, parasternal short basal/mid-papillary/apical, apical four chamber and subcostal four chamber views, and should include a visual estimation of global left ventricular ejection fraction. Other cardiovascular conditions that can be identified using point-of-care ultrasound include: pericardial effusion; cardiac tamponade; and pulmonary embolism. Pulmonary emergency conditions that can be diagnosed using point-of-care ultrasound include pneumothorax; pleural effusion; and interstitial syndrome. The extended focused assessment with sonography for trauma examination may of value in patients who are hypotensive in order to identify intra-abdominal haemorrhage, pneumothoraces and haemothoraces.

Barriers to reducing preoperative testing for low-risk surgical procedures: A qualitative assessment guided by the Theoretical Domains Framework

INTRODUCTION

While numerous guidelines do not recommend preoperative tests for low risk patients undergoing low risk surgeries, they are often routinely performed. Canadian data suggests preoperative tests (e.g. ECGs and chest x-rays) preceded 17.9%-35.5% of low-risk procedures. Translating guidelines into clinical practice can be challenging and it is important to understand what is driving behaviour when developing interventions to change it.

AIM

Thus, we completed a theory-based investigation of the perceived barriers and enablers to reducing unnecessary preoperative tests for low-risk surgical procedures in Newfoundland, Canada.

METHOD

We used snowball sampling to recruit surgeons, anaesthesiologists, or preoperative clinic nurses. Interviews were conducted by two researchers using an interview guide with 31 questions based on the theoretical domains framework. Data was transcribed and coded into the 14 theoretical domains and then themes were identified for each domain.

RESULTS

We interviewed 17 surgeons, anaesthesiologists, or preoperative clinic nurses with 1 to 34 years' experience. Overall, while respondents agreed with the guidelines they described several factors, across seven relevant theoretical domains, that influence whether tests are ordered. The most common included uncertainty about who is responsible for test ordering, inability to access patient records or to consult/communicate with colleagues about ordering decisions and worry about surgery delays/cancellation if tests are not ordered. Other factors included workplace norms that conflicted with guidelines and concerns about missing something serious or litigation. In terms of enablers, respondents believed that clear institutional guidelines including who is responsible for test ordering and information about the risk of missing something serious, supported by improved communication between those involved in the ordering process and periodic evaluation will reduce any unnecessary preoperative testing.

CONCLUSION

These findings suggest that both health system and health provider factors need to be addressed in an intervention to reduce pre-operative testing.

The comparative and added prognostic value of biomarkers to the Revised Cardiac Risk Index for preoperative prediction of major adverse cardiac events and all-cause mortality in patients who undergo noncardiac surgery

BACKGROUND

The Revised Cardiac Risk Index (RCRI) is a widely acknowledged prognostic model to estimate preoperatively the probability of developing in-hospital major adverse cardiac events (MACE) in patients undergoing noncardiac surgery. However, the RCRI does not always make accurate predictions, so various studies have investigated whether biomarkers added to or compared with the RCRI could improve this.

OBJECTIVES

Primary: To investigate the added predictive value of biomarkers to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Secondary: To investigate the prognostic value of biomarkers compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Tertiary: To investigate the prognostic value of other prediction models compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery.

SEARCH METHODS

We searched MEDLINE and Embase from 1 January 1999 (the year that the RCRI was published) until 25 June 2020. We also searched ISI Web of Science and SCOPUS for articles referring to the original RCRI development study in that period.

SELECTION CRITERIA

We included studies among adults who underwent noncardiac surgery, reporting on (external) validation of the RCRI and: - the addition of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of the RCRI to other models. Besides MACE, all other adverse outcomes were considered for inclusion.

DATA COLLECTION AND ANALYSIS

We developed a data extraction form based on the CHARMS checklist. Independent pairs of authors screened references, extracted data and assessed risk of bias and concerns regarding applicability according to PROBAST. For biomarkers and prediction models that were added or compared to the RCRI in ≥ 3 different articles, we described study characteristics and findings in further detail. We did not apply GRADE as no guidance is available for prognostic model reviews.

MAIN RESULTS

We screened 3960 records and included 107 articles.   Over all objectives we rated risk of bias as high in ≥ 1 domain in 90% of included studies, particularly in the analysis domain. Statistical pooling or meta-analysis of reported results was impossible due to heterogeneity in various aspects: outcomes used, scale by which the biomarker was added/compared to the RCRI, prediction horizons and studied populations.  Added predictive value of biomarkers to the RCRI Fifty-one studies reported on the added value of biomarkers to the RCRI. Sixty-nine different predictors were identified derived from blood (29%), imaging (33%) or other sources (38%). Addition of NT-proBNP, troponin or their combination improved the RCRI for predicting MACE (median delta c-statistics: 0.08, 0.14 and 0.12 for NT-proBNP, troponin and their combination, respectively). The median total net reclassification index (NRI) was 0.16 and 0.74 after addition of troponin and NT-proBNP to the RCRI, respectively. Calibration was not reported. To predict myocardial infarction, the median delta c-statistic when NT-proBNP was added to the RCRI was 0.09, and 0.06 for prediction of all-cause mortality and MACE combined. For BNP and copeptin, data were not sufficient to provide results on their added predictive performance, for any of the outcomes. Comparison of the predictive value of biomarkers to the RCRI  Fifty-one studies assessed the predictive performance of biomarkers alone compared to the RCRI. We identified 60 unique predictors derived from blood (38%), imaging (30%) or other sources, such as the American Society of Anesthesiologists (ASA) classification (32%). Predictions were similar between the ASA classification and the RCRI for all studied outcomes. In studies different from those identified in objective 1, the median delta c-statistic was 0.15 and 0.12 in favour of  BNP and NT-proBNP alone, respectively, when compared to the RCRI, for the prediction of MACE. For C-reactive protein, the predictive performance was similar to the RCRI. For other biomarkers and outcomes, data were insufficient to provide summary results. One study reported on calibration and none on reclassification. Comparison of the predictive value of other prognostic models to the RCRI   Fifty-two articles compared the predictive ability of the RCRI to other prognostic models. Of these, 42% developed a new prediction model, 22% updated the RCRI, or another prediction model, and 37% validated an existing prediction model. None of the other prediction models showed better performance in predicting MACE than the RCRI. To predict myocardial infarction and cardiac arrest, ACS-NSQIP-MICA had a higher median delta c-statistic of 0.11 compared to the RCRI. To predict all-cause mortality, the median delta c-statistic was 0.15 higher in favour of ACS-NSQIP-SRS compared to the RCRI. Predictive performance was not better for CHADS2, CHA2DS2-VASc, R2CHADS2, Goldman index, Detsky index or VSG-CRI compared to the RCRI for any of the outcomes. Calibration and reclassification were reported in only one and three studies, respectively.

AUTHORS' CONCLUSIONS

Studies included in this review suggest that the predictive performance of the RCRI in predicting MACE is improved when NT-proBNP, troponin or their combination are added. Other studies indicate that BNP and NT-proBNP, when used in isolation, may even have a higher discriminative performance than the RCRI. There was insufficient evidence of a difference between the predictive accuracy of the RCRI and other prediction models in predicting MACE. However, ACS-NSQIP-MICA and ACS-NSQIP-SRS outperformed the RCRI in predicting myocardial infarction and cardiac arrest combined, and all-cause mortality, respectively. Nevertheless, the results cannot be interpreted as conclusive due to high risks of bias in a majority of papers, and pooling was impossible due to heterogeneity in outcomes, prediction horizons, biomarkers and studied populations. Future research on the added prognostic value of biomarkers to existing prediction models should focus on biomarkers with good predictive accuracy in other settings (e.g. diagnosis of myocardial infarction) and identification of biomarkers from omics data. They should be compared to novel biomarkers with so far insufficient evidence compared to established ones, including NT-proBNP or troponins. Adherence to recent guidance for prediction model studies (e.g. TRIPOD; PROBAST) and use of standardised outcome definitions in primary studies is highly recommended to facilitate systematic review and meta-analyses in the future.

Expert opinion on the preoperative medical optimization of adults with diabetes undergoing metabolic surgery

Diabetes mellitus (DM) and obesity are interrelated in a complex manner, and their coexistence predisposes patients to a plethora of medical problems. Metabolic surgery has evolved as a promising therapeutic option for both conditions. It is recommended that patients, particularly those of Asian origin, maintain a lower body mass index threshold in the presence of uncontrolled DM. However, several comorbidities often accompany these chronic diseases and need to be addressed for successful surgical outcome. Laparoscopic Roux-en-Y gastric bypass (RYGB) and laparoscopic sleeve gastrectomy (LSG) are the most commonly used bariatric procedures worldwide. The bariatric benefits of RYGB and LSG are similar, but emerging evidence indicates that RYGB is more effective than LSG in improving glycemic control and induces higher rates of long-term DM remission. Several scoring systems have been formulated that are utilized to predict the chances of remission. A glycemic target of glycated hemoglobin < 7% is a reasonable goal before surgery. Cardiovascular, pulmonary, gastrointestinal, hepatic, renal, endocrine, nutritional, and psychological optimization of surgical candidates improves perioperative and long-term outcomes. Various guidelines for preoperative care of individuals with obesity have been formulated, but very few specifically focus on the concerns arising from the presence of concomitant DM. It is hoped that this statement will lead to the standardization of presurgical management of individuals with DM undergoing metabolic surgery.

Establishing consensus on the perioperative management of cholecystectomy in public hospitals: a Delphi study with an expert panel in Mexico

BACKGROUND

Several guidelines have put forward recommendations about the perioperative process of cholecystectomy. Despite the recommendations, controversy remains concerning several topics, especially in low- and middle-income countries. The aim of this study was to develop uniform recommendations for perioperative practices in cholecystectomy in Mexico to standardize this process and save public health system resources.

METHODS

A modified Delphi method was used. An expert panel of 23 surgeons anonymously completed two rounds of responses to a 29-item questionnaire with 110 possible answers. The consensus was assessed using the percentage of responders agreeing on each question.

RESULTS

From the 29 questions, the study generated 27 recommendations based on 20 (69.0%) questions reaching consensus, one that was considered uncertain (3.4%), and six (20.7%) items that remained open questions. In two (6.9%) cases, no consensus was reached, and no recommendation could be made.

CONCLUSIONS

This study provides recommendations for the perioperative management of cholecystectomy in public hospitals in Mexico. As a guide for public institutions in low- and middle-income countries, the study identifies recommendations for perioperative tests and evaluations, perioperative decision making, postoperative interventions and institutional investment, that might ensure the safe practice of cholecystectomy and contribute to conserving resources.

Non-cardiac surgery in patients with coronary artery disease: risk evaluation and periprocedural management

Perioperative cardiovascular complications are important causes of morbidity and mortality associated with non-cardiac surgery, particularly in patients with coronary artery disease (CAD). Although preoperative cardiac risk assessment can facilitate the identification of vulnerable patients and implementation of adequate preventive measures, excessive evaluation might lead to undue resource utilization and surgical delay. Owing to conflicting data, there remains some uncertainty regarding the most beneficial perioperative strategy for patients with CAD. Antithrombotic agents are the cornerstone of secondary prevention of ischaemic events but substantially increase the risk of bleeding. Given that 5-25% of patients undergoing coronary stent implantation require non-cardiac surgery within 2 years, surgery is the most common reason for premature cessation of dual antiplatelet therapy. Perioperative management of antiplatelet therapy, which necessitates concomitant evaluation of the individual thrombotic and bleeding risks related to both clinical and procedural factors, poses a recurring dilemma in clinical practice. Current guidelines do not provide detailed recommendations on this topic, and the optimal approach in these patients is yet to be determined. This Review summarizes the current data guiding preoperative risk stratification as well as periprocedural management of patients with CAD undergoing non-cardiac surgery, including those treated with stents.

Perioperative Cardiovascular Risk Assessment and Management for Noncardiac Surgery: A Review

IMPORTANCE

Perioperative cardiovascular complications occur in 3% of hospitalizations for noncardiac surgery in the US. This review summarizes evidence regarding cardiovascular risk assessment prior to noncardiac surgery.

OBSERVATIONS

Preoperative cardiovascular risk assessment requires a focused history and physical examination to identify signs and symptoms of ischemic heart disease, heart failure, and severe valvular disease. Risk calculators, such as the Revised Cardiac Risk Index, identify individuals with low risk (<1%) and higher risk (≥1%) for perioperative major adverse cardiovascular events during the surgical hospital admission or within 30 days of surgery. Cardiovascular testing is rarely indicated in patients at low risk for major adverse cardiovascular events. Stress testing may be considered in patients at higher risk (determined by the inability to climb ≥2 flights of stairs, which is <4 metabolic equivalent tasks) if the results from the testing would change the perioperative medical, anesthesia, or surgical approaches. Routine coronary revascularization does not reduce perioperative risk and should not be performed without specific indications independent of planned surgery. Routine perioperative use of low-dose aspirin (100 mg/d) does not decrease cardiovascular events but does increase surgical bleeding. Statins are associated with fewer postoperative cardiovascular complications and lower mortality (1.8% vs 2.3% without statin use; P < .001) in observational studies, and should be considered preoperatively in patients with atherosclerotic cardiovascular disease undergoing vascular surgery. High-dose β-blockers (eg, 100 mg of metoprolol succinate) administered 2 to 4 hours prior to surgery are associated with a higher risk of stroke (1.0% vs 0.5% without β-blocker use; P = .005) and mortality (3.1% vs 2.3% without β-blocker use; P = .03) and should not be routinely used. There is a greater risk of perioperative myocardial infarction and major adverse cardiovascular events in adults aged 75 years or older (9.5% vs 4.8% for younger adults; P < .001) and in patients with coronary stents (8.9% vs 1.5% for those without stents; P < .001) and these patients warrant careful preoperative consideration.

CONCLUSIONS AND RELEVANCE

Comprehensive history, physical examination, and assessment of functional capacity during daily life should be performed prior to noncardiac surgery to assess cardiovascular risk. Cardiovascular testing is rarely indicated in patients with a low risk of major adverse cardiovascular events, but may be useful in patients with poor functional capacity (<4 metabolic equivalent tasks) undergoing high-risk surgery if test results would change therapy independent of the planned surgery. Perioperative medical therapy should be prescribed based on patient-specific risk.

Protocol for assessing the determinants of preoperative test-ordering behaviour for low-risk surgical procedures using a theoretically driven, qualitative design

INTRODUCTION

Current evidence suggests that preoperative tests such as chest X-rays, electrocardiograms and baseline laboratory studies may not be useful for healthy patients undergoing low-risk surgical procedures. Routine preoperative testing for healthy patients having low-risk surgery is not a scientifically sound practice. In this study, we will interview healthcare providers working at medical facilities where low-risk surgical procedures are carried out. This will allow us to gain insight into the determinants of preoperative testing behaviours for healthy patients undergoing low-risk surgeries and their barriers and enablers to guideline adherence.

METHODS AND ANALYSIS

We will use semistructured interviews with anaesthesiologists, surgeons and preadmission clinic nurses to assess the determinants of preoperative testing behaviours. The interview guide was designed around the Theoretical Domains Framework (TDF), developed specifically to determine the barriers and enablers to implementing evidence-based guidelines. Interviews will be audio-recorded, transcribed verbatim and coded according to the TDF. Key themes will be generated for each of the identified domains.

ETHICS AND DISSEMINATION

We have received ethics approval from the Health Research Ethics Board in Newfoundland and Labrador (HREB #2018.190) for this study. The results of this work will be disseminated through a peer-reviewed publication, presentation at a healthcare forum and plain-language infographic summaries. Additionally, deidentified data collected and analysed for this study will be available for review from the corresponding author on reasonable request.

Electrocardiographic and echocardiographic features in patients with major arterial vascular disease assigned to surgical revascularization

Background: We aimed to depict the electrocardiographic and echocardiographic aspects in patients before elective major vascular surgery.Methods: We evaluated through standard 12 lead electrocardiography and transthoracic echocardiography 469 patients with asymptomatic large abdominal aortic aneurysm (AAA), 334 with critical carotid stenosis (CAS), and 238 with advanced peripheral artery disease (PAD) before surgical revascularization.Results: Patients with AAA were predominantly males (p < .001) with normal sinus rhythm (p = .026), were more affected by atrioventricular block (p = .033) and left anterior fascicular block (p < .001). They also presented larger aortic root size (p < .001) and septal hypertrophy (p = .036), in addition, atrial fibrillation was less frequent in the same group (p = .023). Patients with CAS were of older age (p < .001) with a substantial number of females (p < .001). They presented less left ventricular segmental kinetic disorders and fewer dilated ventricles (p = .004 and p < .001 respectively). Finally, those with PAD had reduced septal and posterior wall thickness (p < .01, p = .009 respectively), greater mitral and aortic annular calcification (p < .001), and were more affected by previous myocardial infarction (p < .001). The PR interval, left anterior fascicular block and aortic root size were independently associated with aneurysm, previous myocardial infarction with PAD, while smaller left ventricular end systolic volumes with carotid artery stenosis.Conclusions: Patients with AAA were mostly affected by cardiac conduction disorders, septal hypertrophy, aortic root dilation and less affected by atrial fibrillation. Patients with CAS were older with more normal sized ventricles, whereas, previous myocardial infarction was most common amongst patients with peripheral artery disease.

Routine Preoperative Electrocardiograms in Patients at Low Risk for Cardiac Complications During Shockwave Lithotripsy: Are They Useful?

INTRODUCTION

Routine preoperative electrocardiogram (ECG) before shockwave lithotripsy (SWL) is frequently performed despite recommendations against its use in asymptomatic patients undergoing low-risk surgical procedures. This study assesses whether routine preoperative ECG before SWL is useful in patients at low risk for cardiac complications.

MATERIALS AND METHODS

A retrospective study of SWL at our center (2003-2013) reviewed all cardiac-related preoperative cancellations, intraoperative complications, postoperative admissions, and emergency department presentations in patients at low risk for cardiac complications. Patients received SWL with sedation and continuous five-lead ECG monitoring.

RESULTS

Of 30,892 referrals, preoperative ECG triggered 13 (0.04%) cancelations in low-risk patients (1 with new atrial fibrillation and 12 with ischemia/previous infarction). Of these patients, 1 had a subsequent abnormal cardiac work-up and 11 underwent uncomplicated SWL without cardiac intervention (2 had unknown history). Of 27,722 treatments, 5 (0.02%) were stopped prematurely in low-risk patients because of arrhythmia (3 had normal preoperative ECG, 1 had abnormal ECG, and 1 did not complete ECG). Three patients developed an arrhythmia with sedation and 2 patients were admitted postoperatively because of cardiac complications (1 for atrial fibrillation and 1 for hypertension), of whom all had normal preoperative ECG. No patients presented to our emergency department with cardiac complications after SWL.

CONCLUSIONS

In patients at low risk for cardiac complications, preoperative ECG triggered very few cancellations and did not predict early termination of treatment or cardiac complications after SWL. These findings suggest that in low-risk patients, routine preoperative ECG has little effect on treatment or complication rate and should be omitted.

Preoperative Anesthetic Considerations in the Podiatric Surgical Candidate

There are multiple challenges the podiatric surgeon faces while attempting to treat patients in the perioperative setting. Given the aging and increasingly complex surgical population, preoperative evaluation is of utmost importance to mitigate unnecessary risks and to optimize patient outcomes. This article reviews key preoperative considerations, patient evaluation, and factors affecting selection of anesthetic technique.

Preoperative Cardiac Evaluation for Noncardiac Surgery

Cardiac risk stratification before surgery informs consent, may advise optimization interventions, and guides intraoperative and postoperative management and monitoring. Published guidelines provide an outline for risk stratification but are only updated every 5 to 10 years; hence, cardiology expert opinion is often needed. Preoperative cardiovascular evaluation starts with an excellent history and physical examination. Accurate assessment of exercise tolerance is paramount in defining risk and determining the need for further testing. Risk/benefit ratio needs to be assessed and reviewed with all stakeholders, which pertains to deciding on cardiac intervention before surgery and bleeding versus thrombosis risk when managing medications.

Preoperative Laboratory Testing

Obtaining routine preoperative laboratory tests increases health care costs and has been listed, by the Choosing Wisely Campaign, as one of the top 5 practices anesthesiologists should avoid. Routine testing without clinical indication is not cost-effective and could cause harm and unnecessary delays. Abnormal findings are more likely to be false positive and costly to pursue, introduce new risks, and increase anxiety for the patient. Preoperative testing need to be performed only following a targeted history and physical examination, factoring severity of surgery, and comorbidities such that the benefit of the test outweighs risk.

Prognostic Significance and Clinical Utility of Intraventricular Conduction Delays on the Preoperative Electrocardiogram

The prognostic significance of the preoperative electrocardiogram (ECG), particularly intraventricular conduction delays (IVCDs), on postoperative outcomes among patients undergoing noncardiac surgery is uncertain. In a retrospective cohort, we evaluated the risk associated with preoperative IVCDs on in-hospital death and postoperative myocardial infarction (POMI). The 152,479 patients who underwent noncardiac surgery were categorized by preoperative electrocardiographic findings: normal (36.1%), left bundle branch block (LBBB, 1.2%), right bundle branch block (2.9%), nonspecific IVCD (3.3%), and any other ECG abnormality (56.5%). The primary and secondary outcomes were postoperative in-hospital mortality and POMI, respectively. In multivariable-adjusted models, compared with normal ECGs, each electrocardiographic abnormality category was associated with increased risk of postoperative death: LBBB odds ratio (OR) 1.89 (95% confidence interval [CI] 1.35 to 2.65), right bundle branch block OR 1.73 (95% CI 1.33 to 2.24), nonspecific IVCD OR 1.95 (95% CI 1.53 to 2.48), and other abnormal ECG OR 1.94 (95% CI 1.68 to 2.25). ECGs with conduction delays did not confer increased risk of postoperative death compared with other ECG abnormalities. Moreover, receiver operating characteristic analysis of models incorporating demographic and co-morbidity data demonstrated marginal additive benefit of any electrocardiographic data. Risk of POMI was not significantly increased among ECGs with conduction delays compared with both normal and other abnormal ECGs. In conclusion, patients with intraventricular conduction disease, including LBBB, on preoperative ECG are not at greater risk of postoperative in-hospital death or POMI compared with patients with other ECG abnormalities. Furthermore, any preoperative electrocardiographic abnormalities, including intraventricular delays, provide marginal clinical utility beyond demographic and clinical history for predicting postoperative in-hospital death or POMI.

Preoperative tests recommendations in adult patients for ambulatory surgery

Anesthetic assessment traditionally included a series of laboratory tests intended to detect undiagnosed diseases, and to ensure that the patient undergoes surgery following safety criteria. These tests, without a specific clinical indication, are expensive, of questionable diagnostic value and often useless. In the context of outpatient surgery, recent evidence suggests that patients of any age without significant comorbidity, ASA physical status gradei and grade ii, do not need additional preoperative tests routinely. The aim of the present recommendations is to determine the general indications in which these tests should be performed in ASA gradei and grade ii patients undergoing ambulatory surgery.

A case-cohort study of postoperative myocardial infarction: impact of anemia and cardioprotective medications

OBJECTIVE

Postoperative myocardial infarction (poMI) is a serious and costly complication. Multiple risk factors for poMI are known, but the effect of anemia and cardioprotective medications have not been defined in real-world surgical practice.

METHODS

Patients undergoing inpatient elective surgery were assessed at 17 hospitals from 2008 to 2011 for the occurrence of poMI (American Heart Association definition). Non-MI control patients were chosen randomly on the basis of case type. Descriptive, univariable, and multivariable statistical analysis were performed for primary outcomes of poMI and death at 30 days.

RESULTS

Compared with controls (N = 304), patients with poMI (N = 222) were older (72 ± 11 vs 60 ± 17 years, P < .0001), had a lesser preoperative hematocrit (37 ± 6 vs 39 ± 5, P < .0001), more often were smokers, had a preoperative T-wave abnormality (21% vs 9%, P < .0001), and had a preoperative stress test with a fixed deficit (26% vs 3%; P < .001). Preoperative factors associated with poMI included peripheral vascular disease (odds ratio 2.6; 95% confidence interval 1.3-5.3), tobacco use (1.7; 1.01-2.9), history of percutaneous coronary angioplasty (2.8; 1.6-5.0), and age (1.05; 1.03-1.07), whereas hematocrit >35 (0.51; 0.32-0.82) and preoperative acetylsalicylic acid, ie, aspirin (0.59; 0.4-0.97) were protective. Preoperative β-blockade, statin, and use of angiotensin-converting enzyme inhibitors were not associated with lesser rates of poMI. Non-MI complication rates were 23-fold greater in the poMI group compared with the control group (P < .0001). Mortality with poMI within 30 days was 11% compared with 0.3% in non-MI control patients (P < .0001). In patients with poMI, factors independently associated with death included use of epidurals (3.5; 1.07-11.4) and bleeding (4.2; 1.1-16), whereas preoperative use of aspirin (0.29; 0.1-0.88), and postoperative β-blockade (0.18; 0.05-0.63) were protective. Cardiac catheterization, percutaneous coronary intervention, or coronary artery bypass grafting after poMI was performed in 34% of those alive and 20% of those who died (P = .16).

CONCLUSION

In the current era, poMI patients have a markedly increased risk of death. This risk is decreased with preoperative use of acetylsalicylic acid and post MI β-blockade. Further study is warranted to explore the role of anemia and cardiac interventions after poMI.

Preoperative risk assessment--from routine tests to individualized investigation

BACKGROUND

Risk assessment in adults who are about to undergo elective surgery (other than cardiac and thoracic procedures) involves history-taking, physical examination, and ancillary studies performed for individual indications. Further testing beyond the history and physical examination is often of low predictive value for perioperative complications.

METHOD

This review is based on pertinent articles that were retrieved by a selective search in the Medline and Cochrane Library databases and on the consensus-derived recommendations of the German specialty societies.

RESULTS

The history and physical examination remain the central components of preoperative risk assessment. Advanced age is not, in itself, a reason for ancillary testing. Laboratory testing should be performed only if relevant organ disease is known or suspected, or to assess the potential side effects of pharmacotherapy. Electrocardiography as a screening test seems to add little relevant information, even in patients with stable heart disease. A chest X-ray should be obtained only if a disease is suspected whose detection would have clinical consequences in the perioperative period.

CONCLUSION

In preoperative risk assessment, the history and physical examination are the strongest predictors of perioperative complications. Ancillary tests are indicated on an individual basis if the history and physical examination reveal that significant disease may be present.

Patients with ischemic heart disease

Ischemic heart disease (IHD) occurs when myocardial oxygen supply is not adequate for myocardial oxygen demand. Patients with IHD who are undergoing surgery are at risk for development of perioperative cardiac events (PCEs), and this risk depends on the type of surgery, the presence of clinical risk factors, and functional status of the patients. Appropriate perioperative management of medications such as dual antiplatelet therapy and β-blockers has a significant impact on outcomes. Perioperative management decisions should be communicated clearly between the surgeon, cardiologist, and anesthesiologist in charge of the patient. Appropriate perioperative management reduces the incidence of PCEs.