Major Surgery

The primary objective of this study is to develop and validate a multivariable risk prediction model for 30-day major postoperative complications and mortality in patients undergoing major surgery across participating international centers. Despite advancements in perioperative care, surgical complications remain a leading cause of global morbidity and preventable death, particularly in resource-limited or low- and middle-income country (LMIC) settings. This study utilizes a prospective, multicenter, international cohort design. Data will be collected on patient-level risk factors (e.g., age, frailty, comorbidities), hospital-level infrastructure (e.g., nurse-to-patient ratios, rescue capacity), and perioperative safety processes (e.g., adherence to the WHO Surgical Safety Checklist). Patients will be followed prospectively for up to 30 days post-surgery. The collected data will be used to construct robust predictive models to identify individual patient risk and uncover actionable system-level factors to optimize surgical safety globally.

Limiting perioperative tachycardia (aiming for a heart rate \<90 beats per minute throughout the perioperative period) using the ultra-short acting beta-blocker landiolol in patients with cardiovascular risk factors undergoing major surgery might lower the incidence of perioperative myocardial injury. Feasibility of the intervention needs to be proven prior to conduction of a larger trial.

During major surgical procedures performed under general anesthesia, changes in blood flow and oxygen delivery to tissues may occur due to blood loss, hemodynamic fluctuations, and anesthesia-related physiological effects. These changes can lead to impaired tissue perfusion, which is commonly reflected by increased arterial lactate levels. However, lactate measurements are intermittent and may not detect early perfusion abnormalities. This prospective observational study aims to investigate the relationship between submental tissue oxygenation measured by near-infrared spectroscopy (NIRS), microvascular reactivity assessed by the vascular occlusion test, and arterial lactate levels during major surgery. Adult patients undergoing major abdominal, neurosurgical, or orthopedic procedures will be monitored intraoperatively using non-invasive NIRS techniques, while arterial blood gas analyses will be performed as part of routine clinical care. The study does not involve any changes to standard anesthesia or surgical management. All treatments and clinical decisions will be made by the responsible care team according to routine practice. By evaluating non-invasive indicators of tissue oxygenation and microvascular function, this study aims to improve the understanding of early intraoperative tissue perfusion changes and their association with metabolic markers.

The primary objective of the study is to evaluate the efficacy of standard handover with AnesList© between physician anesthesists in operating room, for a complete transmission for a patient, on the occurence of event as death, serious complications or rehospitalization in month of postoperative after major surgery.

The goal of this clinical trial is to determine whether treating pain after surgery with ketamine is more effective when administered intravenously as a continuous infusion or through a patient-controlled analgesia (PCA) pump. This study focuses on adult volunteers following major orthopedic surgery. We have two main questions to address: * Is a continuous intravenous infusion of ketamine as effective as ketamine administered through a PCA pump for managing pain after major orthopedic surgery. * Does a continuous intravenous infusion of ketamine result in lower opioid requirements compared to ketamine delivered through a PCA pump for pain management after major orthopedic surgery? Participants will be divided into two groups. One group will receive ketamine via continuous infusion, while the other will receive it through a PCA pump. Both groups will also receive a placebo (a substance that looks like the drug but contains no active ingredients), ensuring that neither group knows whether they are receiving ketamine through the PCA pump (which always contains a painkiller) or as a continuous infusion. Participants will be assigned to one of the two groups and will receive their assigned treatment for 48 hours while hospitalized. Researchers will visit participants during their first three days in the hospital to assess their pain levels and monitor for any side effects.

This multicentric, randomised controlled trial is to the investigators knowledge the first implementation of a multimodal, multidisciplinary prehabilitation approach using knowledge from different specialties to lower complications and to increase cost effectiveness after major surgery in elderly, frail patients.