View clinical trials related to Unconsciousness.
Filter by:This research study is designed to investigate the effect of hypoglycemia (low blood sugar) on blood flow to and biochemistry in the brain.
This is a single center, single-blind randomized cross over design trial that will compare the impact of intra-nasal naloxone vs. intra-nasal saline administration during experimental hypoglycemia on day one on responses to experimental hypoglycemia on day two. Investigators intend to enroll 18 individuals to obtain the complete data sets from 15 participants. Expected duration of subject participation is 10-12 weeks. This study will consist of two 2-day intervention visits separated by approximately 8 weeks.
Positron Emission Tomography (PET), Magnetic Resonance Imaging (MRI) and electroencephalography (EEG) studies will be carried out to reveal the neural correlates of consciousness. Consciousness of the subjects will be manipulated with anesthetic agents dexmedetomidine, propofol, S-ketamine and sevoflurane. One-hundred-and-sixty (160) healthy male subjects will be recruited to receive EC50 concentration of the anesthetic (40 dexmedetomidine, 40 propofol, 20 S-ketamine, 40 sevoflurane) or placebo (20) while being imaged for cerebral metabolic rate of glucose (CMRglu). Also genetic, immunological and metabolomics samples will be taken and analysed to find possible genetic factors explaining the variability in drug response and to find chemical fingerprints of acute drug effect.
St. Michael's Hospital (SMH) provides service to individuals with some of the most severe brain injuries and intensive care needs in Canada. These patients often require prolonged intensive care admissions, lengthy hospital stays, involvement of many health professionals, and long-term support for ongoing care requirements. Many hospitals face resource limitations, specifically involving the health disciplines and their ability to provide frequent intervention. It has been proposed that multisensory stimulation (i.e. exposing the patient to various sights, sounds, smells, etc.) in the early stages of brain injury recovery may result in improved responsiveness/cognitive function. Previous research has indicated a potential benefit for early multisensory stimulation intervention for patients with severe brain injury. However there is still not enough conclusive evidence to confirm whether the intervention is truly effective. The investigators are proposing a pilot randomized controlled study (placebo-controlled, double-blinded) to determine the feasibility and examine the effectiveness of early multisensory stimulation with patients following severe brain injury who remain in a coma, vegetative state, or minimally conscious state. Eligible patients will be randomized to a control group (standard care + family/caregiver education) or an intervention group (standard care + family/caregiver education + early sensory intervention). Data regarding number of patients enrolled, amount of intervention completed, percentage of outcome data collected, patient's level of responsiveness and cognitive function will be collected before and after the intervention period, using several outcome measures. The investigators hope to determine the feasibility of conducting this type of study within this clinical setting and the effectiveness of multisensory stimulation with this patient population.
Propofol in combination with remifentanil or midazolam can result in synergistic or additive effect. The patients who are scheduled to undergo general anesthesia are enrolled in this study. 120 patients will be randomly allocated to 3 groups(P, PR, PMR). The patients in group P will receive general anesthesia only with propofol and group PR and PMR will receive 0.25 mcg/kg/min remifentanil infusion prior to propofol. The patients in group PMR will receive 0.03 mg/kg bolus dose of midazolam 1 min after start of the remifentanil infusion. 'Success' is defined as loss of both verbal response and eyelash reflex in 2 min after propofol administration. When 'success', the next patient will receive the same dose(in 18/19 probability) or 0.25 mg/kg lower dose(in 1/19 probability) of propofol. When 'failure', the next patient will receive 0.25 mg/kg higher dose of propofol at induction period.
213 patients undergoing elective on-pump coronary artery bypass grafting (CABG) were enrolled into this prospective-clinical trial.After hundred and sixty three patients were excluded due to various reasons, 50 patients were randomized to BIS (bispectral index) and MAC (minimum alveolar concentration) groups. In BIS group (Group B, n=25), desflurane was titrated within 40 to 60 BIS values and in MAC group (Group M, n=25) within 0.7 to 1.3 MAC. Primary end point of the study was to investigate the difference of desflurane consumption between groups.
Until today there is no standard-monitoring to specifically reflect the analgesic component of general anesthesia. Quality and safety of general anesthesia are of major clinical importance and can be improved by limiting the administration of opioid analgesics to the minimum dose needed. This study therefore examines the quality of three different monitoring techniques (PhysioDoloris, MetroDoloris, Lille, France, SPI (Surgical Plethysmographic Index), GE Healthcare, Helsinki, Finland and AlgiScan, IDMed, Marseille, France) in assessing the level of analgesia during general anesthesia. Therefore a standardized painful stimulus is applied under different levels of analgesic drugs. The monitor's indices are compared to clinical signs such as an increase in heart rate and blood pressure.
Iatrogenic hypoglycemia is the most frequent acute complication of insulin therapy in people with type 1 diabetes (T1DM). Recurrent hypoglycemic events initiate a process of habituation, characterized by suppression of hypoglycemic symptoms, eventually leading to hypoglycemia unawareness, which creates a particularly high risk of severe hypoglycemia. Recent evidence suggest a pivotal role for (brain) lactate in the pathogenesis of hypoglycemia unawareness. Indeed, exogenous lactate administration may preserve brain function and attenuate counterregulatory responses to and symptomatic awareness of hypoglycemia. It is unknown whether endogenous elevation of plasma lactate produces the same effects and whether such effects differ between patients with T1DM with and without hypoglycemia unawareness and healthy controls. Objective: To investigate the effect of elevated levels of endogenous lactate on brain lactate accumulation and on counterregulatory responses to, symptomatic awareness of and cognitive function during hypoglycemia in patients with T1DM with and without hypoglycemia unawareness and normal controls. Hypothesis: The investigators hypothesize first that endogenous lactate, when raised through high intensity exercise, preserves neuronal metabolism during subsequent hypoglycemia, which in turn will attenuate counterregulatory hormone responses, appearance of symptoms and deterioration of cognitive function. Second, the investigators posit that these effects will be augmented in patients with hypoglycemia unawareness compared to healthy subjects and T1DM patients with normal awareness as a consequence of greater transport capacity of lactate into the brain.
A prospective, randomised, phase IV trial including 150 patients. To evaluate the effects of varied concentrations of remifentanil on the proposal requirements for the loss of consciousness and response to pain and to evaluate the haemodynamic changes and processed EEG (BIS) during induction of anaesthesia.
Closed-loop strategy is composed of three components: glucose sensor to read glucose levels, insulin pump to infuse insulin and a dosing mathematical algorithm to decide on the required insulin dosages based on the sensor's readings. A dual-hormone closed-loop strategy would regulate glucose levels through the infusion of two hormones: insulin and glucagon. The main objective of this project is to compare the efficacy of single-hormone and dual-hormone closed-loop strategy to regulate overnight glucose levels in a in-patient study in type 1 diabetes adults with hypoglycemia unawareness and documented nocturnal hypoglycemia. The investigators hypothesized that dual-hormone closed-loop strategy is more effective in regulating overnight glucose levels compared to single-hormone closed-loop strategy.