Association of Body Surface Area Versus Body Mass Index on Outcomes in Peripheral Arterial Disease.

OBJECTIVE: Numerous studies have indicated that increased obesity in patients with established peripheral artery disease (PAD) is inversely associated with disease prognosis, a phenomenon coined as the "obesity paradox". A major cause of criticism in studies investigating the obesity paradox is the use of body mass index (BMI) as a surrogate marker in defining and quantifying the degree or severity of obesity. We conducted a retrospective review to verify whether the obesity paradox persists in patients with PAD when using body surface area (BSA) as an alternative anthropometric measure. METHODS: Patients undergoing surgery (open or endovascular) for PAD between January 2009 and March 2020 were identified from the Vascular Quality Initiative (VQI) national database. The association between BSA/BMI and risk of post-operative complications was evaluated using logistic regression and restricted cubic spline analysis, both of which adjusted for demographic and comorbid risk predictors. When analyzing BSA and BMI as categorical variables, patients were grouped according to BSA quintiles and the World Health Organization (WHO) BMI categories. RESULTS: A total of 130,428 patients were included based on our eligibility criteria, of which 85,394 (65.5%) were men. Patients were typically hypertensive (87.8%), diabetic (50.4%), and overweight (63.0% over 25 kg/m2). Patients with a high BMI or BSA typically presented at a younger age and with greater pre-operative administration of drugs (statin, ACE-inhibitor, anticoagulant, and beta blocker). Our results indicate that BSA and BMI are inversely associated with post-operative risk of all-cause morbidity, mortality, and cardiac complications. This finding was displayed when analyzing BMI/BSA as a continuous variable, or when indexing patients into BMI/BSA groups. CONCLUSION: Our data suggests that the obesity paradox persists in patients with PAD when using either BMI or BSA as anthropometric measures. Future studies with a prospective design and utilizing newer anthropometric indices should be conducted to fully verify the presence of this phenomenon.

Advancing Precision in 3D Echocardiography: Incorporating 3D Markers to Aid Spatial Orientation.

The incorporation of 3D imaging into diagnostic and interventional echocardiography has rapidly expanded in recent years. Applications such as multiplanar reconstruction that were once considered research tools and required off-cart analysis can now readily be performed at the point of image acquisition and in real-time during live image acquisition for procedural guidance. While the application and quality of 3D images have significantly improved in recent years, there remains a noticeable lag in the evolution of artificial intelligence that would further simplify the interpretative processes, both during live sessions and offline analyses. Users are still required to mentally reconstruct sliced images during multiplanar reconstruction based on color-coded planes. While this may be an effortless task for the seasoned echocardiographer, it can be a challenging task for echocardiographers who are less familiar with 3D imaging and multiplanar reconstruction. This article describes the utility of using 3D markers to aid in image interpretation.

Misidentification of the True Aortic Annulus With 2-dimensional Echocardiography: A Critical Appraisal Using 3-Dimensional Imaging.

OBJECTIVES: This study aimed to evaluate the accuracy of identifying the true aortic valve (AV) annulus using 2-dimensional (2D) echocardiography, with the goal of highlighting potential misidentification issues in clinical practice. DESIGN: An observational study employing 3-dimensional (3D) datasets to generate 2D images of the AV annulus for analysis. SETTING: The study was conducted in an academic medical center. PARTICIPANTS: Three-dimensional transesophageal echocardiography datasets were obtained from 11 patients with normal AV and aortic root anatomies undergoing coronary artery bypass surgery. Attending anesthesiologists certified by the National Board of Echocardiography (NBE) were approached subsequently to participate in this study. INTERVENTIONS: Two images per patient were generated from 3D datasets, reflecting the mid-esophageal long-axis view of the AV, a true AV annulus image, and an off-axis image. A survey was distributed to NBE-certified perioperative echocardiographers across 12 academic institutions to identify the true AV annulus from these images. MEASUREMENTS AND MAIN RESULTS: The survey, completed by 45 qualified respondents, revealed a significant misidentification rate of the true AV annulus, with only 36.8% of responses correctly identifying it. The rate of correct identification varied across image sets, with 44.4% of participants unable to correctly identify any true AV annulus image. CONCLUSIONS: The study highlighted the limitations of 2D echocardiography in accurately identifying the true AV annulus in complex 3D structures like the aortic root. The findings suggest a need for greater reliance on advanced imaging modalities, such as 3D echocardiography, to improve accuracy in clinical practice.

A Multidisciplinary Protocolized Approach for Ruptured Abdominal Aortic Aneurysm Management: A Retrospective Before-After Study.

OBJECTIVES: To investigate whether implementation of a multidisciplinary protocol for ruptured abdominal aortic aneurysm (rAAA) management reduces rates of adverse complications. DESIGN: A retrospective before-after study. SETTING: A tertiary-care academic hospital. PARTICIPANTS: Adult patients who underwent open or endovascular rAAA repair; data were stratified into before-protocol implementation (group 1: 2015-2018) and after-protocol implementation (group 2: 2019-2022) groups. INTERVENTION: The protocol details the workflow for vascular surgery, anesthesia, emergency department, and operating room staff for a rAAA case; training was accomplished through yearly workshops. MEASUREMENTS AND MAIN RESULTS: The primary outcome was in-hospital mortality. Secondary outcomes included all-cause morbidity and other major complications. Differences in postoperative complication rates between groups were assessed using Pearson's χ2 test. Of the 77 patients included undergoing rAAA repair, 41 (53.2%) patients were in group 1, and 36 (46.8%) patients were in group 2. Patients in group 2 had a significantly shorter median time to incision (1.0 v 0.7 hours, p = 0.022) and total procedure time (180.0 v 160.5 minutes, p = 0.039) for both endovascular and open repair. After protocol implementation, patients undergoing endovascular repair exhibited significantly lower rates of mortality (46.2% v 20.0%, p = 0.048), all-cause morbidity (65.4% v 44.0%, p = 0.050), and renal complications (15.4% v 0.0%, p = 0.036); patients undergoing open repair for a rAAA exhibited significantly lower rates of mortality (53.3% v 27.3%, p = 0.018) and bowel ischemia (26.7% v 0.0%, p = 0.035). CONCLUSIONS: Implementation of a multidisciplinary protocol for the management of a rAAA may reduce rates of adverse complications and improve the quality of care.

Artificial Intelligence for Anesthesiology Board-Style Examination Questions: Role of Large Language Models.

New artificial intelligence tools have been developed that have implications for medical usage. Large language models (LLMs), such as the widely used ChatGPT developed by OpenAI, have not been explored in the context of anesthesiology education. Understanding the reliability of various publicly available LLMs for medical specialties could offer insight into their understanding of the physiology, pharmacology, and practical applications of anesthesiology. An exploratory prospective review was conducted using 3 commercially available LLMs--OpenAI's ChatGPT GPT-3.5 version (GPT-3.5), OpenAI's ChatGPT GPT-4 (GPT-4), and Google's Bard--on questions from a widely used anesthesia board examination review book. Of the 884 eligible questions, the overall correct answer rates were 47.9% for GPT-3.5, 69.4% for GPT-4, and 45.2% for Bard. GPT-4 exhibited significantly higher performance than both GPT-3.5 and Bard (p = 0.001 and p < 0.001, respectively). None of the LLMs met the criteria required to secure American Board of Anesthesiology certification, according to the 70% passing score approximation. GPT-4 significantly outperformed GPT-3.5 and Bard in terms of overall performance, but lacked consistency in providing explanations that aligned with scientific and medical consensus. Although GPT-4 shows promise, current LLMs are not sufficiently advanced to answer anesthesiology board examination questions with passing success. Further iterations and domain-specific training may enhance their utility in medical education.

Virtual Reality Training for Central Venous Catheter Placement: An Interventional Feasibility Study Incorporating Virtual Reality Into a Standard Training Curriculum of Novice Trainees.

OBJECTIVES: This study assess the feasibility of integrating virtual reality (VR) simulation into the central venous catheter (CVC) placement training curriculum. DESIGN: The study consists of 3 parts: (1) Evaluating current manikin-based training for CVC placement through surveys for senior first-year anesthesia residents and cardiac anesthesia faculty who supervise resident performing the procedure; (2) Interventional study training novice trainees with VR simulator and assessing their reaction satisfaction; and (3) pilot study integrating VR training sessions into CVC training curriculum for first-year anesthesia residents. SETTING: Conducted at a single academic-affiliated medical center from December 2022 to August 2023. PARTICIPANTS: Junior first-year anesthesia residents. INTERVENTIONS: VR training sessions for CVC placements using the Vantari VR system. MEASUREMENTS AND MAIN RESULTS: Primary outcome: novice trainees' satisfaction with VR training for CVC procedure. Satisfaction of resident and faculty with standard manikin-based training was also collected. Faculty expressed concerns about residents' confidence and perceived knowledge in performing CVC placement independently. Novice trainees showed high satisfaction and perceived usefulness with VR training, particularly in understanding procedural steps and developing spatial awareness. Pilot integration of VR training into the curriculum demonstrated comparable training times and emphasized structured stepwise training modules to ensure completion of vital procedural steps. CONCLUSIONS: This study underscores the potential of VR simulation as a complementary training tool for CVC placement rather than a substitution of standard manikin training. VR is offering immersive experiences and addressing limitations of traditional manikin-based training methods. The integration of VR into training curricula warrants further exploration to optimize procedural proficiency and patient safety in clinical practice.

A systematic review and meta-analysis of general versus regional anesthesia for lower extremity amputation.

OBJECTIVE: Postoperative morbidity in patients undergoing lower extremity amputation (LEA) has remained high. Studies investigating the influence of the anesthetic modality on the postoperative outcomes have yielded conflicting results. The aim of our study was to assess the effects of regional anesthesia vs general anesthesia on postoperative complications for patients undergoing LEA. METHODS: We systematically searched PubMed, Embase, MEDLINE, Web of Science, and Google Scholar from 1990 to 2022 for studies investigating the effect of the anesthetic modality on the postoperative outcomes after LEA. Regional anesthesia (RA) included neuraxial anesthesia and peripheral nerve blocks. The outcomes included 30-day mortality, respiratory failure (unplanned postoperative intubation, failure to wean, mechanical ventilation >24 hours), surgical site infection, cardiac complications, urinary tract infection, renal failure, sepsis, venous thrombosis, pneumonia, and myocardial infarction. RESULTS: Of the 25 studies identified, we included 10 retrospective observational studies with 81,736 patients, of whom 69,754 (85.3%) had received general anesthesia (GA) and 11,980 (14.7%) had received RA. In the GA group, 50,468 patients were men (63.8%), and in the RA group, 7813 patients were men (62.3%). The results of the meta-analyses revealed that GA was associated with a higher rate of respiratory failure (odds ratio, 1.38; 95% confidence interval, 1.06-1.80; P = .02) and sepsis (odds ratio, 1.21; 95% confidence interval, 1.11-1.33; P < .0001) compared with RA. No differences were found in postoperative 30-day mortality, surgical site infection, cardiac complications, urinary tract infection, renal failure, venous thrombosis, pneumonia, and myocardial infarction between the GA and RA groups. CONCLUSIONS: The results of our meta-analysis have shown that GA could be associated with a higher rate of respiratory failure and sepsis compared with RA for LEA.

Geometric Indices for Predicting Ischemic Mitral Regurgitation: Correlation of Mitral Valve Coaptation Area With Tenting Height, Tenting Area and Tenting Volume.

OBJECTIVES: Ischemic remodeling of the left ventricle in patients with coronary artery disease (CAD) results in geometric changes of the mitral valve (MV) apparatus, leading to reduced MV leaflet coaptation. Although the calculation of the coaptation area has value in assessing the effects of left ventricular remodeling on the MV, it is difficult and time-consuming to measure. In this study the authors hypothesized that the tenting volume (TV) would have a greater association with coaptation area than tenting height (TH) or tenting area (TA). DESIGN: A retrospective review. SETTING: A single tertiary-care academic hospital. PARTICIPANTS: There were 145 adult patients who underwent coronary artery bypass graft surgery between April 2018 and July 2020. MEASUREMENTS AND MAIN RESULTS: Intraoperative 2- and 3-dimensional transesophageal echocardiographic studies were obtained in the precardiopulmonary bypass period. Offline analysis was used to obtain TH, TA, TV and coaptation area for each patient. Correlation between the coaptation area and the TH, TA, and TV was conducted using Pearson's correlation. The median age of the population was 68.0 years (61.0-73.3), the body mass index was 29.0 kg/m2 (25.7-33.5), and 17.8% were females. Increases in TV were the most reliable predictor of decreases in coaptation area (R2 = 0.75) followed by TA (R2 = 0.48) and TH (R2 = 0.47). CONCLUSION: As a representative of the complete topography of the MV, the authors' study demonstrated that in patients with CAD, TV has a greater negative correlation with coaptation area as compared to TH or TA.

Overview of the Interatrial Septum: Review of Cardiac Nomenclature for Transseptal Puncture.

Transseptal puncture is an increasingly common procedure undertaken to gain access to the left side of the heart during structural heart disease interventions. Precision guidance during this procedure is paramount to ensure success and patient safety. As such, multimodality imaging, such as echocardiography, fluoroscopy, and fusion imaging, is routinely used to guide safe transseptal puncture. Despite the use of multimodal imaging, there is currently no uniform nomenclature of cardiac anatomy between the various imaging modes and proceduralists, and echocardiographers tend to use imaging modality-specific terminology when communicating among the various imaging modes. This variability in nomenclature among imaging modes stems from differing anatomic descriptions of cardiac anatomy. Given the required level of precision in performing transseptal puncture, a clearer understanding of the basis of cardiac anatomic nomenclature is required by both echocardiographers as well as proceduralists; enhanced understanding can help facilitate communication across specialties and possibly improve communication and safety. In this review, the authors highlight the variation in cardiac anatomy nomenclature among various imaging modes.

Structural and Electrical Integrity of Transesophageal Echocardiography Probes: Importance and Key Concepts.

The clinical utility of transesophageal echocardiography (TEE) is well-established for patients undergoing cardiac surgery. With the increase in percutaneous structural heart disease procedures that rely on TEE for procedural guidance, the use of TEE probes is expanding. Although there are well-established protocols for routine cleaning and decontaminating TEE probes between patient use, there is a lack of awareness and misconceptions about maintaining TEE probes' structural and electrical integrity. The electrical leakage test (ELT) is routinely performed between patient use. From a patient safety standpoint, the ELT is necessary to ensure the longevity of this expensive equipment and prevent disruptions to the workflow in a busy department caused by TEE probes being decommissioned due to probe damage. This technical communication aims to highlight the importance of maintaining TEE probes' structural and electrical integrity. The article also highlights and discusses probe handling techniques between patient use, emphasizing the ELT to ensure patient safety and compliance with national and international standards.

Virtual Reality: The Future of Invasive Procedure Training?

Invasive procedures are associated with adverse events that are both hazardous to patients and expensive to treat. A trainee is expected to perform complex sterile invasive procedures in a dynamic environment under time pressure while maintaining patient safety at the highest standard of care. For mastery in performing an invasive procedure, the automatism of the technical aspects is required, as well as the ability to adapt to patient conditions, anatomic variability, and environmental stressors. Virtual reality (VR) simulation training is an immersive technology with immense potential for medical training, potentially enhancing clinical proficiency and improving patient safety. Virtual reality can project near-realistic environments onto a head-mounted display, allowing users to simulate and interact with various scenarios. Virtual reality has been used extensively for task training in various healthcare-related disciplines and other fields, such as the military. These scenarios often incorporate haptic feedback for the simulation of physical touch and audio and visual stimuli. In this manuscript, the authors have presented a historical review, the current status, and the potential application of VR simulation training for invasive procedures. They specifically explore a VR training module for central venous access as a prototype for invasive procedure training to describe the advantages and limitations of this evolving technology.

Novel Three-Dimensionally Printed Ultrasound Probe Simulator and Heart Model for Transthoracic Echocardiography Education.

Simulation-based training is an essential component in the education of transthoracic echocardiography (TTE). Nevertheless, current TTE teaching methods may be subject to certain limitations. Hence, the authors in this study aimed to invent a novel TTE training system employing three-dimensional (3D) printing technology to teach the basic principles and psychomotor skills of TTE imaging more intuitively and understandably. This training system comprises a 3D-printed ultrasound probe simulator and a sliceable heart model. The probe simulator incorporates a linear laser generator to enable the visualization of the projection of the ultrasound scan plane in a 3D space. By using the probe simulator in conjunction with the sliceable heart model or other commercially available anatomic models, trainees can attain a more comprehensive understanding of probe motion and related scan planes in TTE. Notably, the 3D-printed models are portable and low-cost, suggesting their potential utility in various clinical scenarios, particularly for just-in-time training.

Timing of Blood Transfusions and 30-Day Patient Outcomes After Coronary Artery Bypass Graft Surgery.

OBJECTIVE: Packed red blood cell transfusion during coronary artery bypass graft surgery is known to be associated with adverse outcomes. However, the association of the timing between transfusions in relation to discharge and 30-day postoperative outcomes has not been studied. The study authors investigated the impact of transfusion timing on 30-day surgical outcomes. DESIGN: A retrospective review. SETTING: At a single tertiary-care academic hospital. PARTICIPANTS: A total of 2,481 adult patients underwent primary coronary artery bypass graft surgery between January 2014 and December 2020. MEASUREMENTS AND MAIN RESULTS: The relationship between the timing of packed red blood cell transfusion (intraoperative, postoperative, or both) and 30-day postoperative outcome variables was calculated as an odds ratio. The influence of timing of transfusion on adjusted probability of postoperative complications was plotted against the lowest intraoperative hematocrit. The median age of the population was 67 years (60.0-74.0), body mass index was 28.5 (25.6-32.3) kg/m2, and 497 (20.0%) were female. A total of 1,588 (36%) patients received packed red blood cell transfusions; 182 (7.3%) received intraoperative transfusions, 489 (19.7%) received postoperative transfusions, and 222 (9.0%) received both (intraoperative and postoperative transfusions). Postoperative transfusion was associated with significantly higher odds of readmission (1.83 [1.32-2.54], p = 0.002) and heart failure (1.64 [1.2-2.23], p = 0.008) compared to patients with no transfusions; whereas intraoperative transfusions were not. CONCLUSION: The authors' data suggested that the postoperative timing of transfusion in patients undergoing coronary artery bypass graft surgery may be associated with an increased incidence of 30-day heart failure and readmission. Prospective research is needed to conclusively confirm these findings.

Comprehensive Training Model for Procedural Guidance of Transcatheter Mitral Valve Edge-to-Edge Repair: Divide and Conquer Approach.

Transcatheter edge-to-edge repair (TEER) of the mitral valve is a complex procedure requiring continuous image guidance with 2-dimensional and 3-dimensional transesophageal echocardiography. In this context, the role of the echocardiographer is of paramount importance. Training in interventional echocardiography for procedures such as TEER requires comprehending the complicated workflow of the hybrid operating room and advanced imaging skills that go beyond traditional echocardiography training to guide the procedure. Despite TEER being more commonly performed, the training structure for interventional echocardiographers is lagging, with many practitioners not having any formal training in image guidance for this procedure. In this context, novel training strategies must be developed to increase exposure and aid training. In this review, the authors present a step-wise approach to training for image guidance during TEER of the mitral valve. The authors have deconstructed this complex procedure into modular components and have incremental stages of training based on different steps of the procedure. At each step, trainees must demonstrate proficiency before advancing to the next step, thus ensuring a more structured approach to attaining proficiency in this complex procedure.

Three-Dimensional Printing of Patient-Specific Heart Valves: Separating Facts From Fiction and Myth From Reality.

The development of prosthetic heart valves by Dr. Charles Hufnagel in 1952 was a major clinical innovation; however, it was not an ideal solution. Mechanical prosthetic heart valves are rigid, immunogenic, require anticoagulation, do not grow with the patient, and have a finite life.1 An ideal prosthetic valve should overcome all these limitations. Considering the prevalence of valvular heart disorders, there is considerable interest in the creation of patient-specific heart valves. Following the introduction of three-dimensional (3D) printing in 1986 by Chuck Hill, rapid advances in multimodality 3D imaging and modeling have led to a generation of tangible replicas of patient-specific anatomy. The science of organogenesis has gained importance for a multitude of valid reasons: as an alternate source of organs, for realistic drug testing, as an alternative to animal testing, and for transplants that grow with the patient. What scientists imagined to be seemingly impossible in the past now seems just a step away from becoming a reality. However, due to the disruptive nature of this technology, often there are commercially-motivated claims of originality and overstatement of the scope and applicability of 3D printing. It often is difficult to separate fact from fiction and myth from reality. In this manuscript, the authors have reviewed the historic perspective, status of the basic techniques of organogenesis with specific reference to heart valves, and their potential.

Influence of Increasing Age and Body Mass Index of Gender in COVID-19 Patients.

Background: The impact of gender on outcomes in patients suffering from coronavirus disease 2019 (COVID-19) is frequently debated. However, the synchronous influence of additional risk factors is seldom mentioned. With increasing emphasis on identifying patients who are at risk of complications from COVID-19, we decided to conduct a retrospective review to assess the influence of age and body mass index (BMI) on gender-based differences in outcomes. Materials and Methods: A retrospective review of 1288 patients was conducted at a tertiary care hospital. Binary logistic regression was used to assess differences in risk factors and outcomes between genders. The associations between predictors and outcomes were described using odds ratios in tables, forest plots, and regression curves plotted using Sigma Plot. Results: Majority of patients were women (53.6% vs. 46.4%). Median BMI in men was higher than women (p = 0.003). Key predictors for all-cause morbidity/mortality in men were diabetes, chronic kidney disease, and regular use of angiotensin-converting enzyme inhibitors. In women, age >65 and regular use of inhaled steroid were additional risk factors. Men had a higher risk of acute respiratory distress syndrome (2.83 [1.70-4.70]), acute renal failure (1.96 [1.20-3.20]), and had a longer length of stay (0.11 [1.52]). Obesity has a stronger bearing on outcomes in women, and age has a more pronounced effect on outcomes in men. Conclusion: Extremes of BMI and older age are associated with worse outcomes in both men and women. Obesity has a stronger bearing on outcomes of COVID-19 infection in women, while the effect of older age on outcomes is more pronounced in men.