Clinical Research Directory

Early Prediction of ICU Hypotension Using Machine Learning

This prospective observational study aims to develop and internally validate a machine learning model for the early prediction of hypotension in adult intensive care unit patients. The model will use routinely collected non-invasive vital signs, heart rate, medication-dose records, and fluid-balance data recorded during standard ICU care. No intervention will be assigned by the study, and patient management will not be changed according to the model output. The primary aim is to predict hypotension 30 minutes before its occurrence; shorter 5- and 15-minute prediction horizons will also be evaluated.

Epinephrine in the Pediatric Intensive Care Unit: A Dose-Effect Trial

The use of peri-arrest bolus epinephrine (PBE) has emerged as a rescue strategy for life-threatening hypotension in pediatric intensive care units (ICU) despite scant published data supporting its use in this setting. As optimal dosing of PBE in this population is unclear, we aim to determine if an initial dose of 0.5 mcg/kg versus 1.0 mcg/kg yields differences in hemodynamic outcomes. The EPI Dose Study is a single-center, prospective, randomized, double-blind, dose-effect trial measuring systolic blood pressure (SBP) before and after PBE is given. We hypothesize that the 1.0 mcg/kg group will have more robust increases in SBP.

Effectiveness of Hypotension Prediction Index (HPI) in Preventing Hypotension in the Post-Anesthesia Care Unit (PACU)

Postoperative hypotension in the post-anesthesia care unit (PACU) is common and linked to adverse outcomes. The Hypotension Prediction Index (HPI) predicts hypotensive events intraoperatively, but its PACU application is unexplored. This study aims to investigate the effectiveness of HPI-guided monitoring in preventing PACU hypotension.

Impact of Transcutaneous Spinal Stimulation on Blood Pressure and Orthostasis in Spinal Cord Injury

The purpose of this study is to learn whether stimulation applied to the spinal cord through the skin (called transcutaneous spinal stimulation) can help control blood pressure in people with a spinal cord injury. The main questions this study attempts to solve: 1. What are the immediate effects of spinal cord transcutaneous stimulation on BP? 2. Does stimulation produce lasting improvements in BP regulation and subsequently, daily function?

Propofol vs. Ciprofol for Anesthesia Induction in Frail Elderly Patients

Post-induction hypotension (PIH) is a common and critical complication during general anesthesia, particularly in frail elderly patients whose physiological reserves are significantly diminished. PIH is strongly associated with adverse postoperative outcomes, including acute kidney injury (AKI) and myocardial injury. Propofol is the most widely used induction agent but frequently induces circulatory depression. Ciprofol, a novel anesthetic agent developed by optimizing the molecular structure of propofol, has demonstrated improved hemodynamic stability and fewer adverse effects in general populations. However, its specific impact on frail elderly patients remains unestablished. The primary purpose of this single-center, randomized, double-blind, controlled trial is to compare the effects of propofol and ciprofol during anesthesia induction on the incidence of PIH in frail elderly patients undergoing major abdominal surgery. The investigator's hypothesis is that ciprofol will significantly lower the incidence of PIH compared to propofol. Additionally, the study will evaluate secondary clinical outcomes, such as postoperative AKI, postoperative cardiac complications, and the overall quality of recovery, to provide an evidence-based clinical guide for selecting optimal induction agents for this vulnerable patient population.

The Effect of HPI to Reduce Intraoperative Hypotension in Caesarean Sections

During caesarean section, blood pressure variations especially a reduction in blood pressure (or hypotension) can bring harmful effects to mother and baby. This usually occurs after spinal anaesthesia is administered. Usually, the anaesthetist will treat hypotension as it occurs. However, a new medical device is now available to predict hypotension. It is called the Hypotension Prediction Index (HPI). This device allows the prediction of hypotension; hence, treatment can be given before it occurs. It has been widely utilised in major surgeries like abdominal tumour surgery and cardiac surgery worldwide and has shown a substantial reduction in hypotension. This study aims to determine whether the duration and severity of hypotension can be reduced when HPI is used in lower segment caesarean sections. The secondary objective of the study is to determine if the complication rate can be reduced in both mother and baby.

Is Permissive Hypotension Truly Harmless? Early Biomarker Evidence of Subclinical Kidney Injury in Rhinologic Surgery

This study aims to investigate the effects of permissive hypotension, which is routinely used in rhinologic surgeries such as rhinoplasty, septoplasty, and functional endoscopic sinus surgery (FESS), on renal function. Although permissive hypotension has been widely practiced to improve surgical field visibility and reduce intraoperative blood loss, its specific definition is not standardized in the literature. In most studies, maintaining mean arterial pressure (MAP) within the range of 50-65 mmHg is considered permissive hypotension. MAP values below 60 mmHg have been associated with increased risk of cardiac and renal complications. However, in otherwise healthy patients, such episodes are frequently tolerated without clinically apparent renal dysfunction. The kidneys have a strong compensatory reserve capacity, and early tubular injury may not be detected by conventional renal function tests such as serum creatinine. Therefore, the use of more sensitive biomarkers is necessary to detect potential subclinical injury. In this prospective observational study, serum NGAL and cystatin C levels will be measured from routine preoperative and postoperative (12-24 hours) blood samples obtained from adult patients undergoing rhinologic procedures. A ≥25% increase in these biomarkers from baseline will be considered indicative of subclinical acute kidney injury. Additionally, intraoperative hemodynamic data will be monitored, and the duration of MAP \<60 mmHg and MAP \<65 mmHg will be recorded. At the end of the procedure, surgical field conditions will be evaluated using the Boezaart Surgical Field Score. The relationship between these parameters and biomarker changes will be analyzed. The goal of this study is to determine whether early, clinically silent renal injury may occur during permissive hypotension and to provide insight into its potential implications for future renal function. All interventions and blood samplings are part of routine care, and no additional procedures will be performed for research purposes.

Predictors of Clinically Relevant Hypotension and Hypoxemia During Propofol-Based Diagnostic Gastrointestinal Endoscopy

This prospective observational cohort study will evaluate the incidence and independent predictors of clinically relevant hypotension and hypoxemia during propofol-based diagnostic gastrointestinal endoscopy in adult patients at a tertiary referral hospital in Vietnam. Participants undergoing diagnostic upper gastrointestinal endoscopy, colonoscopy, or combined diagnostic procedures with propofol administration will be followed from pre-procedure assessment through the early recovery period. The study will assess demographic, clinical, airway, procedural, and sedation-related variables associated with clinically relevant cardiopulmonary adverse events.

Peripheral pULSe Assessment and Arterial pRessure (PULSAR)

This prospective multicenter observational study aims to investigate the relationship between palpable peripheral pulses and simultaneously measured arterial blood pressure in adult patients with circulatory shock or impending circulatory failure. Peripheral pulse palpation is routinely used in emergency medicine, trauma care, critical care, and cardiopulmonary resuscitation as a rapid clinical assessment of circulation. However, the association between palpable pulses and actual arterial blood pressure remains poorly validated. Patients treated in emergency departments, intensive care units, operating rooms, and other acute care settings will undergo routine pulse palpation at predefined anatomical locations including carotid, femoral, and radial arteries. Simultaneously measured non-invasive and/or invasive arterial blood pressure values will be recorded from routine clinical monitoring systems. Additional clinical variables relevant to circulatory status will also be collected. The study seeks to define blood pressure thresholds associated with pulse palpability and evaluate the agreement between invasive and non-invasive blood pressure measurements in patients with circulatory shock.

Dexmedetomidine Versus Nitroglycerin on Surgical Field Quality and Drug Cost in Functional Endoscopic Sinus Surgeries

Sinus surgery is one of the most prevalent ear, nose, and throat (ENT) surgeries, which is mainly carried out nowadays through functional endoscopic sinus surgery (FESS) and leads to significant improvement in the clinical symptoms of patients with rhinosinusitis. It is necessary to maintain safe conditions for this surgery, and the major problem reported during FESS under general anesthesia (GA) is impaired visibility due to excessive amount of bleeding. This is particularly important for the successful surgery of the ethmoid and sphenoid sinuses because even minimum amount of bleeding might seriously impair the successful completion of the surgery, increase the operational risk, and increase surgery time which are major concerns for both anesthesiologist and ENT specialist. Controlled hypotension is the commonly used technique to limit blood loss and improve visualization in the surgical field during FESS, various techniques have been adopted to achieve controlled hypotension, one of them is the use of pharmacological drugs in the form of volatile anesthetics, direct-acting vasodilators, autonomic ganglion-blockers, and α-adrenergic receptor blockers. Alpha-2 (α-2) receptors are found in the peripheral and central nervous systems, platelets and many other organs including the liver, pancreas, kidney, and eye. Stimulation of the receptors in the brain and spinal cord inhibits neuronal firing causing hypotension, bradycardia, sedation, and analgesia. Alpha-2 (α-2) agonist drugs have sympatholytic, sedative, anesthetic, and analgesic sparing effects, as well as vasoconstrictive effects and thereby reduce intraoperative bleeding. Also, the use of α-2 agonists in the perioperative period has been associated with reduced anesthetic requirements, decreased heart rate and blood pressure. Dexmedetomidine is a highly selective α-2 adrenergic receptor agonist (selectivity ratio for α2: α1 is 1600:1). The sympatholytic effect of dexmedetomidine made it attractive to be used as a hypotensive drug during surgery because of decreasing heart rate (HR) and cardiac output (CO) without decreasing stroke volume unless the plasma concentrates reaches above 5.1 μg/mL. The cardiovascular effects of dexmedetomidine begin with initial hypertension following the administration of a loading dose, due to the activation of α 2B receptors located on vascular smooth muscle, with subsequent hypotension and bradycardia due to centrally mediated decrease in sympathetic tone. Dexmedetomidine also has sedative, amnesic, anxiolytic, hypnotic, and analgesic effects with minimal changes in respiratory variables. Furthermore, it reduces postoperative nausea, vomiting, and shivering. It also reduces delirium in patients after cardiac surgery. Nitroglycerin is a directly acting vasodilator drug frequently used to produce controlled hypotension because it is easily titratable and having very rapid onset as well as rapid offset of action. However, the disadvantages of nitroglycerin are reflex tachycardia and venous congestion which leads to increased blood loss. Aim of the work was improving surgical field quality and drug cost in patients undergoing Functional Endoscopic Sinus Surgeries by comparing between dexmedetomidine and nitroglycerin.

Effects of Transitional Circulation in ELBW Infants

Prematurity is a very important problem in this country. Prematurity can cause problems with organ (such as the brain, heart, kidneys) growth and development. A very important part of keeping premature babies healthy is ensuring good blood flow to all of these organs. Some premature babies have problems with their hearts and getting enough blood out to the rest of their bodies. This problem is referred to as hypotension (low blood pressure) and is found by looking at blood test values and while examining the baby. These babies will need medications to help their heart deliver blood to all of the important areas in their bodies. Babies who have hypotension requiring medications tend to have more problems than premature babies that don't need hypotension medication. Some of these problems include a higher risk of bleeding into their brain, kidney problems, liver problems, intestinal (gut) problems causing difficulty tolerating feeds, and a very dangerous infection of their intestines. Some long term effects include hearing loss, developmental delay, and learning problems in the future that are worse than other premature babies who did not have hypotension. Hypotensive premature babies also have a higher risk of death. The cause of hypotension in the first week of life is still not known. We know that babies have to get used to being in the outside world instead of in the womb. A lot of changes with the heart and lungs have to happen for them to not be affected by that transition. If we could gain a better understanding of those changes, we might be able to prevent some of these issues from happening. This study will look closely at premature babies with and without hypotension to assess the heart and lung changes in the first week of life. To do this, we will use monitoring machines and tests to get a better idea of all the changes that happen. This information will help all neonatologists who care for premature babies.

Levobupivacaine and Lidocaine for Paravertebral Block Causes Greater Hemodynamic Oscillations Than Levobupivacaine

The purpose and the goal of this paper is to show whether the application of a combination of two local anesthetics, as opposed to the application of one local anesthetic at paravertebral block changes the hemodynamic variable. It is therefore a prospective randomized double- blind study, where we do a clinical trial in patients ASA(American Society of Anesthesiologists) 1 and 2 statuses between 18 and 80 years of age, using the ultrasound in plane technology.Upon arrival of patients in the unit for preparation procedures for anesthesia we set the ECG(electrocardiograph), noninvasive blood pressure, oxygen saturation, and arterial cannula in the radial artery After sterile washing of the dorsal surface, paravertebral space was identified with ultrasound using 8 Hz(hertz) linear transducer probe then needle position was confirmed with neurostimulation at the level of 2.0 - 5.0 mA(milliampere). When muscle contraction persisted at 0.4mA(milliampere), the anesthetic was applied in levels of Th 2, Th3, and Th 4 (7,0 milliliters per level). We applied the 0.5 % levobupivacaine and 2 % lidocaine, 7,0 milliliters of mixture per level in one group, while only 0.5 % levobupivacaine also 7,0 milliliters. by level in the second one. After that, the invasive hemodynamic monitoring was placed on patients and the induction with 1 % propofol 2-2.5 mg/kg.and Vecuronium 0,08 mg/kg. was performed with the application of supraglottic airway gel of appropriate size. The maintenance of anesthesia and sedation will be conducted with Propofol 1 % continuously ( 25-150 mcg / kg / min.)The measurements will be taken every 5 minutes during the first hour of the application of paravertebral block, then every 15 minutes during the second hour and if the operation takes more than two hours, the measurements are performed every 30 minutes. Postoperatively, invasive hemodynamic monitoring will be removed in post-anesthesia recovery room together with the arterial cannula and the patient will be sent to the hospital ward with non-invasive hemodynamic monitoring (blood pressure, pulse, saturation) until the termination of the blocks.Statistical methods, By comparing two target groups, we analysed the strength of the test with following assumptions: X2 difference test, the expected difference in variances in stroke volume between groups of 60%, α significance level of 0.05, and the minimum statistical test strength of 85%. The required total sample should include at least 80 patients, that is, 40 per group.Data will be presented in tables and graphs. Descriptive statistics of examined variables with appropriate measures of central tendency will be made. Smirnov -Kolmogorov test will assess the normality of data distribution. According to the received results, the appropriate parametric and / or nonparametric tests will be used. Comparisons of quantitative values between the two groups will be analyzed using the independent t-test or Mann-Whitney U test. Dependent values within each group will be analyzed using analysis of variance for repeated measures or Friedman test. Differences in categorical values will be analyzed by X2 test. The appropriate regression model will be made in order to predict the variability of stroke volume in which the dependent variable will be a variation of the stroke volume, while relevant clinical values will be taken as predictor variables. All P values smaller than 0.05 will be considered significant. This research is to present the main results - the existence of the significant change in Stroke Volume Variation (SVV) between groups using invasive hemodynamic monitoring, the changes of Stroke Volume Variation(SVV) depending on the time from the application within groups, differences in volume compensation of crystalloids and colloids and the need for the application of vasoactive drugs. Furthermore, as a secondary results we will present the time to maximal block development, the duration of post operative analgesia, patient satisfaction and time needed for the full recovery from the block.

Midodrine in Heart Failure With Reduced Ejection Fraction With Hypotension

The evidence-based pharmacologic treatments available for patients with heart failure with reduced ejection fraction (HFrEF) has been established over the last few decades of cardiovascular research. These treatments, termed Foundational Guideline-Directed-Medical Therapies (GDMT), prolong patient life, improve patient-reported symptoms, and reduce hospitalizations for heart failure. A direct effect of most medication classes encompassed within GDMT is the reduction in blood pressure due to their mechanisms of action. In addition, as patients with HFrEF become more advanced in their disease, a significant proportion develop hypotension related to pump failure and autonomic dysfunction, amongst other possible mechanisms. As a result, a significant proportion of HFrEF patients are not optimized on GDMT with hypotension as their limiting barrier that would otherwise have served to improve their heart function, heart failure symptoms, and mortality. Currently, there does not exist any evidence-based strategies to address the problem of hypotension in HFrEF patients who are not optimized on GDMT. Midodrine is an alpha-adrenergic agonist (α1-AR) that exerts its effects on peripheral venous and arteriolar vasculature to increase blood pressure. This medication has been used off-label by some clinicians in the hypotensive HFrEF population to increase blood pressure and has been reported to have beneficial effects in improving GDMT utilization as well as increasing left ventricular ejection fraction (LVEF) in published case reports/case series. There does not exist any randomized prospective data on the use of midodrine in the hypotensive HFrEF population. The investigators' objective is to complete the first open-label, randomized control trial of midodrine in the hypotensive HFrEF population to demonstrate feasibility in performing a trial in this patient population and to show efficacy in increasing blood pressure without associated harm. The results of this trial will be used as the foundation and rationale for future studies assessing the impact of midodrine use on GDMT utilization as well as hard cardiovascular outcomes in the hypotensive HFrEF population, including hospitalizations for heart failure and mortality.

Hydrocortisone Therapy Optimization During Hypothermia Treatment in Asphyxiated Neonates

This is a prospective, single center, pharmacokinetic study of intravenous hydrocortisone therapy for systemic low blood pressure during hypothermia treatment in asphyxiated newborns. Patients will be allocated to hydrocortisone supplementation while receiving conventional inotropic therapy as needed. The hypothesis is that a detailed study of hydrocortisone pharmacokinetics during therapeutic hypothermia would help to personalize steroid supplementation in asphyxiated neonates. As the overall metabolic rate decreases with lower body temperature, drug metabolism is likely to be reduced as well, and lower doses, or less frequent dosing will be sufficient to achieve the targeted steroid range and biological effects in asphyxiated neonates with relative adrenal insufficiency. Thus, the investigators are planning to measure initial, baseline serum cortisol levels and serial serum cortisol levels after hydrocortisone supplementation in cooled asphyxiated neonates.

Effects of Ondansetron on Hemodynamic Changes After Spinal Anesthesia in Geriatric Urologic Surgery

Spinal anesthesia is frequently used in urologic surgery in geriatric patients; however, it may cause significant hemodynamic changes such as hypotension and bradycardia. These changes can be more pronounced in elderly patients due to age-related physiological alterations. Ondansetron, a 5-HT3 receptor antagonist commonly used for the prevention of postoperative nausea and vomiting, has been suggested to attenuate spinal anesthesia-induced hemodynamic instability by modulating vagal reflexes. This prospective observational study aimed to evaluate the effects of ondansetron on hemodynamic changes following spinal anesthesia in geriatric patients undergoing urologic surgery. Hemodynamic parameters were recorded during the intraoperative period, and the incidence of hypotension, bradycardia, and vasopressor requirements were assessed.

Trendelenburg as a First-line Intervention in Critically Ill, Sedated, Invasively Mechanically Ventilated, Hypotensive Patients

A pilot randomized controlled trial to evaluate the efficacy and safety of Trendelenburg position in critically ill patients with hypotension, mainly patients with septic shock and post operative vasoplegia. The main aim is to assess whether Trendelenburg position can improve organ function through a reduction in the need of fluid infusion and dose of vasopressors. Patients will be screened for participation in the study and eventually randomized based on a balanced randomization scheme (1:1) to Trendelenburg position up to 72 hours after intensive care unit (ICU) admission or Semirecumbent position (standard of care).

Effects of Ephedrine, Phenylephrine, Norepinephrine and Vasopressin on Contractility of Human Myometrium and Umbilical Vessels: An In-vitro Study

Hypotension is one of the most common adverse effects of spinal anesthesia for cesarean deliveries, affecting as many as 55-90% of mothers. Hypotension during cesarean deliveries can have detrimental effects on the mother and neonate. Various vasopressors, such as ephedrine, phenylephrine and more recently norepinephrine, have been used for the prevention and treatment of hypotension at cesarean deliveries. Ephedrine was historically considered as the gold standard vasopressor for the management of hypotension during cesarean deliveries. This was based on studies in animal models that showed preserved uteroplacental circulation with ephedrine and not with phenylephrine. However, multiple studies in the past several decades have shown that phenylephrine compared with ephedrine results in a more favorable fetal acid-base status. Consequently, the use of phenylephrine for blood pressure management during cesarean deliveries increased. Recently, norepinephrine was introduced in the obstetrical practice for the management of hypotension at cesarean deliveries, due to its ability to maintain maternal cardiac output better than phenylephrine. Studies have also investigated the use of vasopressin to limit hypotension during CD. There have been case reports of successful vasopressin usage to treat post-spinal hypotension after CD in patients with advanced idiopathic pulmonary arterial hypertension as well as severe mitral stenosis with pulmonary hypertension. Its effect was associated with hemodynamic stability without evidence of harm to the mother or child. However, much controversy still exists surrounding the choice of vasopressor in the obstetric population, in large part due to their varying efficacies, and maternal and fetal effects. Vasopressors used for the treatment of hypotension during cesarean deliveries can have significant direct or indirect effects on the perfusion of uteroplacental and umbilical vessels. Reduction of uteroplacental perfusion and constriction of umbilical vessels can result in fetal acidosis, however, the mechanisms for these effects are unclear. The investigators hypothesize that ephedrine, phenylephrine and norepinephrine and vasopressin have variable effects on the contractility of pregnant myometrium and umbilical arteries due to their variable actions on adrenergic alpha (α) and beta (β) receptors, as well as vasopressin1 and vasopressin2 receptors located in these tissues.

Intraoperative Hypotension in Pancreatoduodenectomy: A Randomized Trial of General Versus Combined Anesthesia

This randomized clinical trial compares the hemodynamic effects of general anesthesia versus combined general anesthesia (thoracic epidural) in patients undergoing pancreatoduodenectomy. The primary aim is to assess the incidence of intraoperative hypotension and related adverse events. Secondary outcomes includes vasopressor requirements, transfusion needs, postoperative complications, intensive care unit admission, hospital length of stay, and mortality.

"Effect of Pre-Spinal Mindfulness-Based Breathing Exercise on Hemodynamic Response in Elective Cesarean Section"

Spinal anesthesia-induced hypotension is one of the most frequent and clinically significant complications of obstetric anesthesia, occurring in up to 50-80% of parturients undergoing elective cesarean section. Preoperative anxiety has been shown to potentiate hemodynamic instability through autonomic nervous system activation, thereby increasing susceptibility to spinal hypotension. This prospective, randomized, controlled trial aims to evaluate the effect of a standardized 5-minute mindfulness-based breathing exercise administered immediately prior to spinal anesthesia on the hemodynamic response in pregnant women scheduled for elective cesarean section. Eligible participants will be randomized in a 1:1 ratio into two parallel groups: the Mindfulness-Based Breathing Exercise Group and the Control Group receiving standard preoperative care. The breathing intervention consists of slow diaphragmatic breathing at a rate of approximately 6 breaths per minute (4-second inhalation through the nose, 6-second exhalation through the mouth), guided by a standardized script delivered by a trained anesthesiologist or nurse. Participants in the intervention group will be instructed to silently repeat the phrase "My body is relaxing as I exhale" with each exhalation, incorporating a mindfulness component. The primary outcome is the maximum decrease in systolic arterial pressure (SAP) within the first 10 minutes following spinal anesthesia induction. Secondary outcomes include preoperative state anxiety scores (STAI-5), early spinal hypotension incidence, heart rate changes, and vasopressor requirements. The study will be conducted at Atatürk University Faculty of Medicine, Department of Anesthesiology and Reanimation, Erzurum, Turkey, in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines.

Predicting Spinal Hypotension in Cesarean Section

This prospective observational study investigates the predictive value of anthropometric and hemodynamic indices for spinal anesthesia-induced hypotension (SAIH) during cesarean section. While spinal anesthesia is preferred for its rapid onset, SAIH remains a frequent complication risking maternal and fetal safety. The study enrolled parturients at Erciyes University, excluding those with hypertension or extreme weight/height. Preoperative measurements included BMI, waist circumference (WC), body roundness index (BRI), and modified shock index (MSI). Following standardized spinal anesthesia with hyperbaric bupivacaine (Harten's dosage), hemodynamic parameters and sensory block levels were monitored. This research aims to determine whether BRI and WC offer superior predictive utility compared with conventional markers such as BMI and MSI to enhance individualized risk assessment in obstetric anesthesia.

Skin Conductance for Predicting Spinal Anesthesia-Induced Hypotension in Geriatric Urologic Oncology Patients

Spinal anesthesia-induced hypotension is a common and clinically significant complication in elderly patients undergoing oncologic surgery. Early identification of patients at risk for hemodynamic instability remains a major challenge in perioperative management. Skin conductance reflects sympathetic nervous system activity and may provide a noninvasive indicator of autonomic responses. This prospective observational study aims to evaluate whether skin conductance measurements can predict the development of hypotension following spinal anesthesia in geriatric oncology patients undergoing urologic surgery. The findings may contribute to improved perioperative monitoring and early risk stratification in this vulnerable patient population.

Vasopressor Impact on Brain Circulation, Organ Blood Flow and Tissue Oxygenation During Anesthesia

The optimal vasopressor for ensuring organ blood flow and tissue oxygen delivery during surgery remains undetermined. This study aim to compare the effects of noradrenaline vs. phenylephrine infusion on blood flow and oxygen delivery to the brain and various other organs in anesthetized neurosurgical patients.

Frequency of Electrical Acupoint Stimulation on Hypotension During Induction

Within 30 minutes before anesthesia, acupoint electrical stimulation at different frequencies were applied at Neiguan and Jian Shi. The changes in blood pressure during the anesthesia induction period were compared between the high-frequency group and the low-frequency group.

Comparing Fluid Responsiveness Assessment Methods in Patients With Impaired Consciousness

Hypotension is a significant precursor to unfavorable clinical outcomes. To determine whether infusion therapy can positively impact the management of hypotension, several evaluative tests can be utilized. These include assessing the collapsibility and distensibility indices of the inferior vena cava, conducting a passive leg raising (PLR) test, and performing a fluid challenge (FC). Technologically advanced methods leveraging dynamic testing are capable of real-time prediction of a patient's response to infusion therapy. Nonetheless, the use of systolic pressure variability (SPV), pulse pressure variability (PPV), and stroke volume variability (SVV) is often limited by the prohibitive costs of the necessary equipment. In contrast, the PLR test and FC are not subject to this limitation. Despite being deemed unreliable by numerous clinical protocols, static measurements of central venous pressure (CVP) or pulmonary capillary wedge pressure (PCWP) persist in usage among certain traditionalists within the medical community. It must be noted that the patient's baseline state and the unique clinical context are pivotal in determining the precision of these methodologies. For example, the PLR test may yield limited information in fully conscious patients, and the prognostic value of CVP measurements is significantly diminished in cases of pneumothorax and hydrothorax. Regrettably, there is a paucity of data on the prognostic utility of these tests in patients with altered levels of consciousness, despite their growing presence in intensive care units. This gap underscores the necessity for comprehensive studies that evaluate the predictive efficacy of infusion therapy responsiveness in patients with concurrent hypotension and impaired consciousness. Purpose of the study: to investigate the sensitivity and specificity of methods for assessing fluid responsiveness in patients with hypotension and decreased level of consciousness.