Clinical Research Directory

Preoperative Exercise Testing and Perioperative Outcomes

The goal of this observational study is to learn whether results from a brief exercise test done before surgery can help identify adults who may be more likely to have problems after moderate- to high-risk noncardiac surgery. The study includes adults older than 45 years who are seen in a pre-surgical evaluation clinic and complete submaximal cardiopulmonary exercise testing, or smCPET, as part of their usual clinical care. The main questions it aims to answer are: Are smCPET measurements linked with early problems after surgery? Are smCPET measurements linked with later problems after surgery, including complications within 30 and 60 days, longer hospital stay, and death? Can smCPET add useful information to standard preoperative risk assessment? Researchers will observe and analyze information collected during routine care. No extra exercise testing or treatment will be done for research. Participants will: * Complete routine preoperative evaluation in the Yale Pre-Surgical Evaluation Clinic. * Undergo smCPET if it is ordered as part of standard clinical care. * Allow researchers to collect information from the medical record and from the exercise test for the study repository, if they agree to participate. The study will collect de-identified information about each participant's health before surgery, exercise test results, details about the surgery and hospital stay, and problems that happen after surgery. This may include age, sex, body mass index, other medical conditions, routine lab and imaging results, heart rate, blood pressure, oxygen levels, smCPET measures such as peak oxygen uptake, anaerobic threshold, and breathing efficiency, and early and late postoperative outcomes. Researchers will look at short-term and later outcomes after surgery. These include problems identified during the hospital stay, such as heart, lung, kidney, nerve, blood, wound, and pain-related complications, as well as complications within 30 and 60 days after surgery. Researchers will also study hospital length of stay and death after surgery. This study is designed to help researchers understand whether a short, practical exercise test can improve the way surgical risk is assessed before an operation. Current preoperative assessment tools do not always measure how well the heart, lungs, and muscles work together during physical stress. smCPET may provide a more objective way to measure functional capacity and physiologic reserve in a busy clinic setting. This is a single-center study based in a preoperative evaluation clinic. The study has a prospective observational cohort component and a retrospective validation component. In the prospective part, adults who meet clinic criteria and complete smCPET during routine care may be asked to join the repository. In the retrospective part, researchers may also review historical data from patients evaluated before smCPET was put into routine use to help compare outcomes and validate findings. Because this is an observational repository study, participation does not change the care participants receive. The exercise test is done for clinical reasons, not because of the research study. The research team will not assign treatments or decide what surgery a participant has. Instead, the team will study how exercise test findings relate to outcomes that occur after surgery. The long-term aim of this study is to improve preoperative risk assessment and help clinicians better identify patients who may need closer monitoring, more evaluation, or more support around the time of surgery. If the findings are useful, they may support broader use of brief preoperative exercise testing in adults having higher-risk noncardiac surgery.

GLS in Difficult CPB Weaning

The goal of this observational study is to learn whether global longitudinal strain (GLS), measured by echocardiography, can predict difficulty separating from cardiopulmonary bypass (CPB) in adults undergoing elective cardiac surgery. The main questions it aims to answer are: * Can preoperative GLS measurement predict difficult separation from CPB? * Are GLS values associated with outcomes such as intensive care unit (ICU) stay, hospital stay, cardiac biomarkers, or 30-day mortality? Participants will: * Undergo standard cardiac surgery requiring CPB * Have echocardiographic assessments (TTE before and after surgery) * Have their recovery and outcomes monitored, including ICU and hospital stay, postoperative labs, and survival within 30 days

BIS in ICU Interventional Study

This study will test whether using a Bispectral Index (BIS) monitor to guide sedation can reduce the amount of sedative medication given to adults in the intensive care unit (ICU) after cardiac surgery. BIS is a non-invasive, EEG-based monitor that shows a number from 0-100 to reflect level of consciousness. Researchers will compare BIS-guided sedation to standard sedation guided by clinical scales (such as the Richmond Agitation-Sedation Scale, RASS). About 144 participants will be randomly assigned (1:1) to one of two groups at two hospitals in Austria (Medical University of Graz and Klinikum Wels-Grieskirchen). In the BIS group, clinicians will use BIS values and standard care to titrate sedation and will aim to avoid sustained BIS values below 50. In the control group, sedation will follow standard practices using clinical scales; BIS will be recorded but hidden from caregivers. The trial is open-label for treating staff; outcome assessors and data analysts will be blinded. Participants will be in the study during their ICU sedation and mechanical ventilation period (typically more than 6 hours), with follow-up through ICU and hospital discharge. The primary outcome is the time-averaged dose of propofol (mg/kg/h) given during continuous ICU sedation until weaning (up to 72 hours). Secondary outcomes include duration of ventilation and sedation, depth of sedation measures, sedative and catecholamine doses, pulmonary infections (including ventilator-associated pneumonia), ICU and hospital length of stay, delirium, and in-hospital mortality. Risks are minimal and may include mild skin irritation from forehead electrodes. Possible benefits include improved sedation management; benefits are not guaranteed. Taking part is voluntary.

GUARD-PH: Guided Use of AI-ECG for Risk Detection of PH in Surgery (GUARD-PH Trial)

This study is a prospective, open-label, randomized controlled trial designed to evaluate a new artificial intelligence (AI) tool for heart monitoring. Researchers will use an AI-enabled electrocardiography (ECG) system to screen patients before they undergo surgery. The main goal is to determine if this AI system can accurately detect pulmonary hypertension and related heart diseases in the preoperative setting. The study is being conducted at Taipei Veterans General Hospital.

Feasibility Study of Novice-Performed Lung Ultrasound for Pneumothorax Detection After Cardiac Surgery

What is the purpose of this study? This study is being done to find out if medical trainees (such as residents and fellows) can learn to use lung ultrasound to detect a collapsed lung (pneumothorax) after heart surgery. Who is participating in the study? Adults who have recently had heart surgery and are having their chest tubes removed in the intensive care unit may be able to join. What will happen during the study? After chest tubes are removed, a trained medical trainee will use a small ultrasound device to check the lungs at the bedside. The patient will also have a chest X-ray, which is the usual test. The results from the ultrasound will be compared to the chest X-ray and reviewed by expert doctors. What is the goal of the study? The goal is to see if it is possible to train medical trainees to use lung ultrasound safely and accurately in real hospital settings. The results will help plan a larger study in the future.

Effective Myocardial Protection Time of Del Nido Cardioplegia in Adult Cardiac Surgery

This single-center, prospective, observational cohort study quantifies the effective myocardial protection window of Del Nido cardioplegia during adult open-heart surgery performed under cardiopulmonary bypass (CPB) and aortic cross-clamp (ACC). Without altering routine care, time-stamped high-sensitivity cardiac troponin (hs-cTn) measurements will be obtained at predefined intraoperative and early postoperative intervals to identify the inflection ("change-point") at which biochemical evidence of ischemic injury begins to rise. Eighty adults undergoing elective valve and/or thoracic aortic procedures with Del Nido cardioplegia will be enrolled. The primary endpoint is the intraoperative hs-cTn change-point time referenced to ACC. Secondary endpoints include associations between change-point and ACC duration, the presence/timing of any re-dose, and early clinical outcomes (e.g., low cardiac output syndrome, maximum VIS in the first 24 h, new arrhythmia or pacemaker need, acute kidney injury by KDIGO, ventilation hours, ICU/hospital length of stay, 30-day MACE and mortality). All cardioplegia choices (dose, route, temperature, re-dose decisions) remain per standard practice; no experimental therapy is administered. Risks are minimal and limited to small-volume blood sampling coordinated with routine draws.

Tracheal Cuff Pressure and Postoperative Complications: A Prospective Observational Study.

This prospective observational study aims to identify risk factors for tracheal mucosal injuries caused by orotracheal tube use during the intraoperative period in patients undergoing elective surgeries at the Hospital de Clínicas de Porto Alegre. The study will recruit patients sequentially for elective procedures requiring general anesthesia and orotracheal intubation. Primary outcomes include symptoms such as hoarseness, pharyngolaryngeal pain, cough, and hemoptysis, assessed up to 30 days post-surgery. A risk score for tracheal injuries will be derived.