Clinical Research Directory

Establishment of Reference Limits for Blood Lactate Levels in Intensive Care Patients With a Particular Focus on Age and Sex

The goal of this observational study is to learn whether there are age- and sex-specific threshold levels of blood lactate that can better predict the risk of death and serious illness in people receiving intensive care, especially those with sepsis (a severe infection that affects the whole body). Lactate is a chemical that the body produces during metabolism. High levels in the blood are often a sign that tissues are not getting enough oxygen, but newer research shows that lactate may also rise due to stress hormones and changes in how cells use energy. Doctors currently define septic shock as sepsis with low blood pressure that does not improve after fluids, combined with a lactate level higher than 2 millimoles per liter (mmol/L). This value was set based on expert agreement but may not be ideal for everyone. Recent studies suggest that even lactate levels below 2 mmol/L can still be linked to a higher chance of dying in the hospital. This study aims to find out if different cutoff levels for men and women, and for different age groups, could improve how doctors identify patients at higher risk, compared with using the same general value for everyone. Main questions: Do older adults and younger adults have different blood lactate thresholds linked to worse outcomes in sepsis? Do men and women show different relationships between lactate levels and risk of death or complications? Can combining lactate levels with other factors (such as blood pressure or medical history) improve predictions of outcome in intensive care? Study design: This is a retrospective observational study based on data from Uppsala University Hospital in Sweden. The study includes all people admitted between 2016 and 2024 who had blood lactate measured during their hospital stay. People without lactate measurements or with unknown identity are excluded. Researchers will analyze the relationship between lactate levels, age, sex, and survival in intensive care. They will use statistical models to find threshold values of lactate linked to higher risk of death or need for advanced care. Machine learning methods, such as clustering algorithms, will be used to identify patient subgroups with similar biological patterns. The researchers will also perform sensitivity analyses to test whether their findings are robust. Why this study matters: If reliable age- and sex-specific lactate thresholds can be identified, doctors may be able to detect patients at risk earlier, even when lactate levels seem normal. This could help guide treatment and monitoring more precisely for each person. The results may contribute to a more personalized definition of septic shock and influence future international guidelines for sepsis management. Background: Traditionally, high lactate levels in sepsis were believed to mean tissues were not getting enough oxygen. However, new evidence shows that lactate can also increase for other reasons, such as overactive stress responses, even when oxygen levels are normal. The liver and kidneys usually remove lactate from the blood, but their function may be reduced during severe infection. Treatments for septic shock currently focus mainly on maintaining blood pressure, but this does not always reflect how well oxygen reaches tissues. Current definitions do not consider differences in how people of various ages or sexes produce or clear lactate. Understanding these differences could improve how doctors interpret blood tests and adjust treatments. Potential benefits: The study will not directly involve new treatments, since it uses existing hospital data. However, its findings may help improve early detection of severe infection, support development of personalized treatment strategies, and reduce death rates among people with sepsis in intensive care. In summary, this study seeks to find better ways to interpret blood lactate levels in intensive care by focusing on age and sex differences. The results may lead to more accurate risk prediction and individualized care for people with sepsis.

Transfusion Practices in Intensive Care Units: a Hungarian Nationwide Survey

The aim of our data analysis-based questionnaire study is to assess the daily transfusion practices used in the care of critically ill patients in intensive care units in Hungary. The rate and frequency of the application of physiological parameters (serum lactate level, central venous oxygen saturation and arteriovenous carbon dioxide difference, arteriovenous oxygen content difference) recommended as transfusion triggers in the international literature in daily practice will be assessed. The aim of our survey is not only to collect statistical data, but also to map practical experiences, knowledge, opinions and possible institutional differences. Our aim is to obtain a more comprehensive picture of the operation of the care system, including transfusion activities, and any possible different practices applied in individual institutions, based on the experiences and observations of colleagues directly involved in patient care.

Timing of Broccoli Sprout Intake to Improve Exercise Performance

This study examines how the timing of intake of a broccoli sprout-based drink (a natural source of isothiocyanates, ITCs) affects physiological responses, recovery, and performance after a standardized endurance cycling session. Healthy, endurance-trained adults (18-64 years) will complete four laboratory visits at the Swedish School of Sport and Health Sciences (GIH): one screening/physiology test visit and three intervention visits in a randomized, double-blind, placebo-controlled cross-over design. On intervention visits, participants will ingest either an active broccoli sprout drink (50 g sprouts) or a placebo drink based on alfalfa sprouts (50 g sprouts) according to randomization. The drink will be consumed either approximately 16 hours before exercise (the evening before) or approximately 3 hours before exercise (the morning of the test), enabling comparison of timing in relation to a standardized \~2-hour cycling protocol (individualized intensity) followed by a 10 km cycling time trial. Outcomes include measures of performance, heart rate, perceived exertion and recovery, blood glucose and lactate, and metabolic responses. Venous blood samples are collected at multiple time points before and after exercise and during the subsequent laboratory recovery period, and muscle biopsies are obtained at defined time points to assess muscle metabolism and recovery-related markers. Participants return \~24 hours after exercise for follow-up sampling after an overnight fast, including a glucose tolerance test

The Acute Effect of Different Resistance Exercise Loads on Irisin and Brain-derived Neurotrophic Factor in Blood Serum and Plasma

The aim of this study is to investigate different resistance training loads on BNDF and irisin levels in platelets, blood serum and plasma.

Evaluating Non-Invasive Haptics During Extreme Exercise

This study aims to compare determinants of endurance performance between participants wearing an active patch with haptic vibrotactile trigger technology (VTT) versus a placebo patch without VTT among recreational to competitive runners over a 4-week training period.

Capacitive Resistive Electric Transfer Therapy on Muscle Recovery

This study aims to evaluate the effectiveness of Capacitive Resistive Electric Transfer (CRET) therapy combined with post-competition massage in the recovery and muscle function of professional athletes. It is designed as a randomized, double-blind, crossover clinical trial. The primary objective is to analyze the efficacy of this combined protocol in muscle recovery after performing the Wingate anaerobic power and capacity test. Secondary objectives include assessing changes in muscle fatigue, muscle function of the rectus femoris and vastus lateralis, physiological changes in blood lactate concentration and oxygen saturation, and intramuscular structural changes through ultrasound before and after the intervention. The study will recruit professional athletes from disciplines that require anaerobic muscle metabolism, such as cycling, athletics, triathlon, CrossFit, and duathlon. Participants must be federated athletes who train at least four times per week and actively compete at regional, national, or international levels. Exclusion criteria include recent sports injuries preventing test performance, prior exposure to CRET therapy, allergies to conductive gel, language barriers, participation in other research studies, or ongoing pharmacological treatment that could interfere with measurements. Participants will attend four study sessions, divided into two sets of two consecutive days. On the first day, they will perform the Wingate test followed by the assigned post-competition massage with either CRET therapy or a placebo intervention. On the second day, they will repeat the Wingate test. After a three-week washout period, participants will switch to the opposite group. The intervention group will receive a 60-minute CRET therapy session with both resistive and capacitive modes applied at different power intensities, combined with a standardized recovery massage. The placebo group will receive the same massage while undergoing a simulated CRET therapy, with the machine turned on but without power application to prevent participant awareness of the placebo condition. The study will analyze various dependent variables, including Wingate test performance, blood lactate levels, subjective fatigue perception using the modified Borg scale, muscle stiffness and tone through myotonometry, muscle oxygen saturation via near-infrared spectroscopy (NIRS), cross-sectional muscle area and grayscale values from ultrasound imaging, body composition using a Tanita analyzer, maximum isometric quadriceps strength via handheld dynamometry, and muscle activity measured by surface electromyography (sEMG). Each of these variables will be assessed at specific time points before, during, and after the intervention. The estimated sample size is approximately 50 subjects, with 25 participants per group, determined through a preliminary pilot study. Statistical analyses will be conducted using IBM SPSS Statistics 26.0. Descriptive statistics will be calculated for quantitative and qualitative variables. A linear mixed model will be applied to compare changes between and within groups over five measurement periods using a one-way mixed ANOVA. If the sphericity assumption is violated, the Greenhouse-Geisser correction will be applied. Statistically significant effects will undergo post-hoc analysis with Bonferroni correction for multiple comparisons. All originally enrolled participants will be included in the final analysis following an intention-to-treat approach, and effect sizes will be calculated using eta squared. The significance level will be set at p \< 0.05.

Exercise-Induced Lactate and Cognitive Function (ExLBC)

A single bout of exercise can rapidly improve cognitive functions including memory, attention, and executive functions, which help us navigate through everyday life. However, we do not fully understand the mechanism behind this process. A promising candidate mechanism is lactate, which was previously considered merely a waste product of our muscles during exercise. It is now recognized as an important molecule that is used by the brain as an energy source. Studies have shown that increases in lactate during exercise are positively related to improved cognitive function after completion of exercise. Another potential mechanism involves the increase in neurotrophins such as brain-derived neurotrophic factor (BDNF) following exercise. The increase in lactate and BDNF during exercise may be connected to cause these cognitive improvements. However, because lactate increases with higher exercise intensities, we currently do not know how lactate specifically impacts brain health. To address this, muscle and blood lactate concentrations can be experimentally manipulated during exercise using sodium bicarbonate (NaHCO3) supplementation and will allow us to explore how lactate specifically affects brain function. The purpose of this project is to investigate the effect of exercise-induced lactate on BDNF and cognition following oral NaHCO3 supplementation in young adults. We hypothesize that BDNF levels will be higher, and cognition will be improved in executive function, visuospatial memory, and working memory in the NaHCO3 condition due to higher plasma lactate during exercise compared to placebo.

Preventive Therapy of Postoperative Intra-abdominal Infection Based on Serum Lactate Changes

Intra-abdominal infection is one of the most serious complications after pancreatic resection. The preventive use of antibiotics intraoperatively could reduce the incidence rate of postoperative intra-abdominal infection. According to the previous retrospective study, changes of serum lactate level on postoperative day1 could predict the incidence rate of postoperative intra-abdominal infection. This prospective RCT is to further validate and promote the findings and conclusion.