Hemodynamics

The goal of this randomized controlled trial is to determine whether low-dose hyperbaric bupivacaine provides better hemodynamic stability and postoperative recovery compared with standard-dose hyperbaric bupivacaine in elderly patients undergoing lower limb orthopedic surgery under spinal anesthesia. The main questions it aims to answer are: * Does low-dose hyperbaric bupivacaine reduce the incidence of intraoperative hypotension and bradycardia compared with standard-dose hyperbaric bupivacaine? * Does low-dose hyperbaric bupivacaine improve postoperative recovery profile compared with standard-dose hyperbaric bupivacaine? Researchers will compare elderly patients receiving low-dose hyperbaric bupivacaine with those receiving standard-dose hyperbaric bupivacaine to determine whether a lower intrathecal dose improves cardiovascular stability and recovery without compromising the effectiveness of spinal anesthesia. Participants will: * Provide written informed consent before enrollment. * Undergo elective lower limb orthopedic surgery under spinal anesthesia. * Be randomly assigned to receive either low-dose or standard-dose hyperbaric bupivacaine. * Have their blood pressure, heart rate, and other vital signs monitored throughout the surgical procedure. * Be assessed for intraoperative hypotension and bradycardia according to predefined study criteria. * Be evaluated for postoperative recovery parameters, including motor recovery and readiness for postoperative recovery and mobilization. The information obtained from this study may help identify a safer and more effective spinal anesthetic technique for elderly patients undergoing orthopedic surgery.

This study will compare two operating-room monitors-stroke volume variation (SVV, from the arterial line) and the Pleth Variability Index (PVI, from the pulse oximeter)-to see which one more accurately predicts whether giving a small fluid bolus will improve the heart's pumping during laparoscopic major abdominal surgery. Adults having elective surgery under general anesthesia will receive two small, timed 250-mL crystalloid infusions as part of routine care (one before and one after creation of the pneumoperitoneum). The research team will record SVV and PVI values just before and three minutes after each infusion while keeping these readings hidden from the clinicians so that usual care is not changed. No experimental drugs or devices are used. The main goal is to learn which index better identifies "fluid responsiveness," so future care can be safer and more consistent. Potential risks are minimal and relate to the small fluid boluses (temporary changes in blood pressure or heart rate); the test stops if the anesthesiologist has any safety concerns. There is no direct benefit to participants, but results may help guide fluid therapy for similar patients in the future. The study is being conducted at a single academic hospital in the Republic of Korea and plans to enroll about 300 adults.

Pneumoperitoneum and Trendelenburg position are unavoidable in laparoscopic surgery and are known to have adverse effects on intraoperative respiratory mechanics and hemodynamics. These conditions increase the risk of ventilator-induced lung injury (VILI) and highlight the importance of lung-protective ventilation strategies. vNOTES (Vaginal Natural Orifice Transluminal Endoscopic Surgery) is a minimally invasive technique that requires less Trendelenburg tilt and lower insufflation pressures compared to conventional laparoscopic surgery, and may therefore offer a more favorable intraoperative profile. This prospective, observational, single-center, parallel-group cohort study aims to compare respiratory mechanics parameters (Ppeak, Pplateau, DP, MPtot, MPdyn, Crs) and hemodynamic parameters (MAP, HR, vasopressor requirement) between vNOTES (n=15) and laparoscopic gynecological surgery (n=15) groups at four intraoperative time points.

Low-flow anesthesia (LFA) is a technique in which at least 50% of the exhaled air, after carbon dioxide absorption, is mixed with a certain amount of fresh gas and returned to the patient during the next inspiration. In 1974, R. Virtue defined minimal flow anesthesia (MFA) as 0.5 L/min. In 1984, Baker and Simionescu classified LFA as 0.5-1 L/min and MFA as 0.25-0.5 L/min. The aim of this study is to investigate whether there are hemodynamic differences between open-heart surgery cases performed with LFA at different fresh gas flow rates.

This study aims to investigate the impact of multiple preoperative antihyperstensive drug use on the burden of post-induction hypotension (PIH) in patients undergoing elective cardiac surgery. The researchers will observe whether the combination of different antihypertensive classes (such as ACE inhibitors, ARBs, beta-blockers, and calcium channel blockers) leads to a higher incidence and severity of blood pressure drops and increased need for vasoactive support during the period between anesthesia induction and surgical incision.

Sepsis, a life-threatening syndrome, is often accompanied by tachycardia in spite of adequate volume resuscitation to correct hypovolemia and vasopressor medication to correct hypotension. Recently, relevant studies have shown that sustained tachycardia in sepsis was also related to high mortality, and appropriate control of heart rate could improve prognosis. Ivabradine reduces heart rate directly without a negative inotropic effect through inhibition of the If ionic current，which is absent from the traditional rate control drug (beta-blockers). This is a prospective, multicenter, randomized, open label study designed to compare ivabradine with placebo on the difference of heart rate and haemodynamics in patients with sepsis.

Heart rate variability (HRV) provides a non-invasive assessment of autonomic control of the nervous system over the heart. During pregnancy, the cardiovascular system adapts significantly, affecting HRV and hemodynamics. Studying the relationship between HRV and hemodynamic changes is critical to understanding and monitoring cardiovascular health during pregnancy and postpartum, and predicting potential complications.

This study aims to compare the efficacy of intravenous dexmedetomidine infusion versus virtual reality (VR) in reducing maternal anxiety, stress, and hemodynamic instability during cesarean section and their effects on neonatal outcome as respiration and heart rate.

This prospective observational study aims to evaluate the impact of operating room noise on bispectral index (BIS) and hemodynamic parameters in patients undergoing general anesthesia. Environmental noise in operating rooms, often overlooked, may influence anesthesia depth, patient safety, and physiological stability. A total of 70 adult patients (ASA I-II, 18-65 years, elective surgery under general anesthesia) will be enrolled at Başakşehir Çam and Sakura City Hospital. Patients will be categorized into two groups based on intraoperative average noise levels: noisy group (\>65 dB) and quiet group (\<55 dB). Noise levels will be measured every 10 minutes using a CEM DT-8850 sound level meter, BIS will be recorded every 10 minutes, and hemodynamic variables (systolic, diastolic, mean arterial pressure, and heart rate) will be recorded every 5 minutes. Primary outcome is the correlation between mean intraoperative noise levels (LAeq) and BIS values during the maintenance phase of anesthesia. Secondary outcomes include the relationship between noise characteristics (e.g., device-related, human-related, alarms, media) and hemodynamic stability, as well as surgical branch-related noise classifications (high, moderate, low). The study is non-interventional, with no additional risk to participants beyond standard clinical monitoring. Findings are expected to provide evidence on the role of environmental noise in anesthesia quality, inform operating room organization, and contribute to patient safety improvements.

In patients after cardiac surgery, disturbances in macrocirculatory fluctuations and tissue perfusion commonly coexist. The stress state induced by factors such as surgical manipulation, cardiopulmonary bypass, anesthetic agents, pain, and ischemia-reperfusion injury, along with the use of vasoactive drugs postoperatively, often leads to increased blood pressure fluctuations in the early postoperative period. Additionally, dysregulation of organ blood flow autoregulation post-surgery contributes to peripheral circulatory impairment, rendering perfusion pressure an unreliable indicator of actual organ perfusion. We aim to assess postoperative blood pressure fluctuation using blood pressure variability and evaluate peripheral circulatory status via the perfusion index. In this prospective cohort study, we will examine the correlation between these two parameters and perioperative adverse events.

In this clinical trial, the authors will compare two tourniquet deflation techniques and their clinical implications on hemodynamics and acid base parameters in hypertensive orthopedic patients undergoing upper limb surgeries under general anesthesia.

In total knee arthroplasty (TKA), the use of a tourniquet and controlled hypotension is common. However, ischemia-reperfusion injury induced by the tourniquet and inappropriate controlled hypotension can lead to cardiac and cerebral damage in patients. Consequently, maintaining hemodynamic stability, ensuring adequate cerebral perfusion, and achieving controlled blood pressure during the perioperative period are critical factors influencing patient outcomes. Postoperatively, patients typically experience moderate to severe pain. Severe postoperative pain can result in prolonged hospital stays, increased readmission rates, elevated opioid consumption, and associated nausea and vomiting. Therefore, exploring effective multimodal postoperative pain management strategies is essential. Nalbuphine, an opioid analgesic acting as a full kappa-receptor agonist and a partial mu-receptor antagonist, is considered to provide analgesic efficacy equivalent to morphine while potentially offering advantages in maintaining hemodynamic stability. This study aims to investigate the effects of administering equivalent doses of nalbuphine at different perioperative time points on analgesia and hemodynamics in elderly patients undergoing knee arthroplasty.

By assessing the safety and durability of an endovascular intervention, this study will justify and inform the design of a subsequent seamless feasibility/pivotal trial aimed at the treatment of intracranial atherosclerotic stenosis (ICAS), an entity which carries a high risk of stroke despite existing medical therapies, and has no other treatment options. Given the global burden of ICAS as a leading cause of stroke, there is a high potential for public health impact not just in the U.S., but world-wide.

The aim of this study was to compare the effect-site target concentration (including EC₅₀ and EC₉₀) of remifentanil required to suppress cardiovascular responses to tracheal intubation during anesthesia induction with etomidate combined with either lidocaine or sufentanil.

This study aims to address the challenges of enteral nutrition support in critically ill ICU patients with varying gastrointestinal function. We'll use bedside Doppler ultrasound to monitor superior mesenteric artery (SMA) blood flow changes post - feeding, exploring its correlation with Acute Gastrointestinal Injury (AGI) and other hemodynamic indicators. Our goals are to identify the patterns of SMA blood flow changes, establish a predictive model linking SMA blood flow reactivity to AGI risk, and propose individualized enteral nutrition strategies based on intestinal hemodynamics. Through this innovative approach, we hope to enhance the safety of enteral nutrition, reduce AGI incidence, and improve patient outcomes.

In this study, researchers examined the changes in related indicators such as immune function, splenic vein,proper hepatic artery, and portal venous hemodynamics following laparoscopic resection of a splenic artery aneurysm. We determined the changes in these patient-related indicators after surgical treatment and whether these changes could improve patient outcomes.

This study tests a new non-invasive device called DARE to monitor blood pressure in patients in intensive care. It compares the device's readings to standard invasive methods and also looks at how well it measures other vital signs like temperature, oxygen levels, and heart rhythm. The goal is to improve patient safety and comfort while helping doctors detect problems earlier.

Ambulatory surgery is increasingly used in anesthesia. In case of general anesthesia, it is recommended to use anesthesia molecules with a short half-life and low doses of opiates to ensure a rapid awakening and to prevent nausea and vomiting by systematic administration of anti-emetics during the operation. Opiates (including sufentanil) have recently been called into question because of the nausea and vomiting and the delay in waking up induced by these molecules. To combat these side effects, the authors have proposed either to reduce the doses or to substitute them with dexmedetomidine, a sedative antihypertensive drug. Recent studies have demonstrated that opiates used in general anesthesia can be replaced by dexmedetomidine. However, literature data are controversial concerning the hemodynamic impact. No study has compared the hemodynamic profile of opioid-free anesthesia with dexmedetomidine versus conventional anesthesia with opioids. The ambulatory context lends itself to the use of dexmedetomidine because it is aimed at a population without strong cardiac pathology, concerns non-major interventions, with the need to optimize pain and side effects. The study authors therefore wish to compare the effects of induction of general anesthesia with low-dose Dexmedetomidine versus sufentanil, on post-induction hemodynamic stability in scheduled outpatient surgeries. The investigators hypothesize that hemodynamic stability at induction of general anesthesia with low-dose dexmedetomidine is not inferior to that obtained with sufentanil in scheduled ambulatory surgeries.

The goal of this clinical trial is to demonstrate the importance of arterial pressure measurement sites during major abdominal surgeries. This randomized controlled trial will compare arterial pressure measurements obtained from radial artery catheterization (the current standard method of monitoring) with those obtained from brachial artery catheterization (a more accurate reflection of central arterial pressure). At the end of the study, we are looking to answer the following questions: 1. Does arterial pressure measurement sites influence the amount of vasopressors that is administered during major abdominal surgeries? 2. What are the instances where there is a difference between peripheral (radial catheter) and central (brachial catheter) monitoring and what are the risk factors leading to the appearance of this radial-brachial pressure gradient? 3. With the data collected, can artificial intelligence based analysis help predict the reliability of a radial monitoring and help guide clinicians on choosing a peripheral versus central arterial pressure monitoring site? All adult participants who are scheduled for elective major abdominal surgeries and meeting our inclusion criteria will be approached and included if they consent. Participants will be randomized 1:1 in the intervention group and the standard of care group. In the intervention group, the brachial arterial line will be used intraoperatively to guide vasopressor and fluid administration. A radial line will also be installed to measure the radial arterial pressure simultaneously, but will not be used to guide hemodynamic management. In the standard of care group, both lines will be installed just like in the intervention group, however, it is the radial arterial line that will guide fluid and vasopressor administration. In both groups, the anesthesia protocol will be standardized and the anesthesiologist will be blinded to the arterial pressure measurement site.

Hyperthermic Intraperitoneal Chemotherapy (HIPEC) involves the intraoperative administration of heated chemotherapeutic agents into the abdominal cavity following cytoreductive surgery (CRS). The increasing use of CRS combined with HIPEC has introduced certain procedural and physiological considerations that distinguish it from other surgical interventions, posing unique challenges for researchers and clinicians alike. Despite advancements in surgical and anesthetic techniques, this combined approach is frequently associated with significant hemodynamic instability, coagulation abnormalities, respiratory complications, and nutritional imbalances. The study aims to contribute to the existing body of knowledge by examining the physiological alterations induced by HIPEC, thereby offering practical insights and guidance for investigators involved in the management and study of this complex therapeutic modality.

Propofol has a rapid onset and short duration of action, making it widely used for induction of general anesthesia. However, its prominent drawback is circulatory depression. Our research team previously proposed an individualized dosing method for the titration of propofol. We then compared the effects of different titration rates of propofol on hemodynamics and stress during general anesthesia induction. It was found that the incidence of hypotension during the induction period was lower in the 0.5 mg/kg/min group, with lower stress levels and faster postoperative recovery. However, this group still had a 25.3% incidence of hypotension. Therefore, we plan to further study the differences in hemodynamics, depth of anesthesia, stress response, and postoperative recovery in three groups of patients induced with a constant infusion rate of propofol at 0.5 mg/kg/min titrated to an OAA/S score of 1, an OAA/S score of 2, and BIS ≤ 60, combined with remifentanil 2 μg/kg. This study aims to explore the appropriate propofol titration endpoint during general anesthesia induction to maintain stable perioperative haemodynamics and achieve rapid postoperative recovery.

Muscle haemodynamics has so far been assessed using at most 2-3 near-infrared spectroscopy devices on isolated muscles and without correlating variables. At the same time, research on musculoskeletal pathologies is limited, and there are no studies that analyse the haemodynamic changes that occur when the anterior cruciate ligament (ACL) is injured and whether these changes last over time. The aim of the study is to monitor and evaluate the physiological changes produced by ACL injury on muscle performance using non-invasive near-infrared spectroscopy (NIRS) devices in trained athletes. This descriptive cross-sectional observational multicentre multicentre study, with Balearic Islands ethics committee IB 5585/24PI, will include males aged 18-65 years who have undergone ACL surgery, divided into 3 groups that: have an evolution of less than 6 months (ACL1), more than 2 years since the surgical intervention and are already practising normal physical-sports activities (ACL2) and the control group (CON) that has never suffered an ACL affectation to date. The 3 groups will perform an incremental intervallic test (4:1) on a cycloergometer or treadmill (according to the specificity of their sport), where different muscular haemodynamic variables will be assessed using 12-24 NIRS devices. The main study variables will be the muscular haemodynamic values of each muscle analysed and their correlation between them: muscular oxygen saturation, absolute capillary haemoglobin, loaded and unloaded with oxygen and relative muscular haemoglobin blood flow, loaded and unloaded with oxygen. Secondary variables will be heart rate, socio-demographic variables (age, toxic habits, injury and sports history) and subjective perception of effort (RPE-20).