A model relating C(e)pro and C(e)remi to AAI/2, BIS, and IoC has been developed and prospectively validated. Based on these models, the (C(e)pro, C(e)remi) concentration pairs that provide an RSS score of 4 range from (1.8 μg·mL(-1), 1.5 ng·mL(-1)) to (2.7 μg·mL(-1), 0 ng·mL(-1)). These concentrations are associated with AAI/2 values of 25 to 30, BIS of 71 to 75, and IoC of 72 to 76. The presence of noxious stimulation increases the requirements of C(e)pro and C(e)remi to achieve the same degree of sedative effects.
Background:The presence of the A118G single nucleotide polymorphism in the OPRM1 gene as well as noxious stimulation might affect the requirements of remifentanil for patients undergoing ultrasonographic endoscopy under sedation-analgesia with propofol and remifentanil. Bispectral index (BIS) was used as a surrogate measure of effect. Methods:A total of 207 patients were screened for A118G and randomly received different combinations of propofol and remifentanil, changed depending on the nausea response to endoscopy tube introduction. Nonlinear mixed effects modelling was used to establish the relation between propofol and remifentanil with respect to BIS and to investigate the influence of A118G or noxious stimulation. The value of k e0 for propofol and remifentanil was estimated to avoid the hysteresis between predicted effect site concentration (Ce) and BIS. Results: Data from 176 patients were analysed. Eleven were recessive homozygous for A118G (OPRM = 1). A total of 165 patients were either dominant homozygous or heterozygous and considered normal (OPRM = 0). The estimated values of k e0 for propofol and remifentanil were 0.122 and 0.148 min −1 . Propofol and remifentanil were synergistic with respect to the BIS (α = 1.85). EC 50 estimate for propofol was 3.86 µg/ml and for remifentanil 19.6 ng/ml in normal patients and 326 ng/ml in OPRM = 1 patients. BIS increases around 4% for the same effect site concentrations with noxious stimulation. Conclusions: Predicted effect site concentration of remifentanil ranging 1-5 ng/ml synergistically potentiates the effects
The availability of large, deidentified health datasets has enabled significant innovation in using machine learning (ML) to better understand patients and their diseases. However, questions remain regarding the true privacy of this data, patient control over their data, and how we regulate data sharing in a way that that does not encumber progress or further potentiate biases for underrepresented populations. After reviewing the literature on potential reidentifications of patients in publicly available datasets, we argue that the cost—measured in terms of access to future medical innovations and clinical software—of slowing ML progress is too great to limit sharing data through large publicly available databases for concerns of imperfect data anonymization. This cost is especially great for developing countries where the barriers preventing inclusion in such databases will continue to rise, further excluding these populations and increasing existing biases that favor high-income countries. Preventing artificial intelligence’s progress towards precision medicine and sliding back to clinical practice dogma may pose a larger threat than concerns of potential patient reidentification within publicly available datasets. While the risk to patient privacy should be minimized, we believe this risk will never be zero, and society has to determine an acceptable risk threshold below which data sharing can occur—for the benefit of a global medical knowledge system.
Abstract-Monitoring the levels of sedation-analgesia may be helpful for managing patient stress on minimally invasive medical procedures. Monitors based on EEG analysis and designed to assess general anesthesia cannot distinguish reliably between a light and deep sedation. In this work, the Poincaré plot is used as a nonlinear technique applied to EEG signals in order to characterize the levels of sedation-analgesia, according to observed categorical responses that were evaluated by means of Ramsay Sedation Scale (RSS). To study the effect of high frequencies due to EMG activity, three different frequency ranges (FR1=0.5-110 Hz, FR2=0.5-30 Hz and FR3=30-110 Hz) were considered. Indexes from power spectral analysis and plasma concentration of propofol and remifentanil were also compared with the bispectral index BIS. An adaptive Neurofuzzy Inference System was applied to model the interaction of the best indexes with respect to RSS score for each analysis, and leave-one-out cross validation method was used. The ability of the indexes to describe the level of sedation-analgesia, according with the RSS score, was evaluated using the prediction probability (Pk). The results showed that the ratio SD1/SD2FR3 contains useful information about the sedation level, and SD1FR2 and SD2FR2 had the best performance classifying response to noxious stimuli. Models including parameters from Poincaré plot emerge as a good estimator of sedation-analgesia levels.
Cardiovascular failure or shock, of any etiology, is characterized by ineffective perfusion of body tissues, inducing derangements in the balance between oxygen delivery and consumption. Impairment in oxygen availability on the cellular level causes a shift to anaerobic metabolism, with an increase in lactate and hydrogen ion production that leads to lactic acidosis. The degree of hyperlactatemia and metabolic acidosis will be directly correlated to the development of organ failure and poor outcome of the individuals. The amount of oxygen available at the tissues will depend fundamentally on an adequate level of perfusion pressure and oxygen delivery. The optimization of these two physiologic parameters can re-establish the balance between oxygen delivery and consumption on the cellular level, thus, restoring the metabolism to its aerobic paths. Monitoring variables such as lactate and oxygen venous saturations (either central or mixed) during the initial resuscitation of shock will be helpful to determine whether tissue hypoxia is still present or not. Recently, some new technologies have been developed in order to evaluate local perfusion and microcirculation, such as gastric tonometry, near-infrared spectroscopy and videomicroscopy. Although monitoring these regional parameters has demonstrated its prognostic value, there is a lack of evidence regarding to its usefulness during the resuscitation process. In conclusion, hemodynamic resuscitation is still based on the rapid achievement of adequate levels of perfusion pressure, and then on the modification of oxygen delivery variables, in order to restore physiologic values of ScvO(2)/SvO(2) and resolve lactic acidosis and/or hyperlactatemia.
ObjectiveEvaluation of the ratio of oxyhaemoglobin to total haemoglobin in skeletal muscle (StO2) using near-infrared spectroscopy may aid in the monitoring of patients with sepsis. This study assessed the benefits and risks of targeting StO2 in adults with severe sepsis or septic shock.DesignA European randomised controlled trial was performed on two parallel groups.SettingFive intensive care units (ICU) in France, Greece, Spain and Germany were used for the study.ParticipantsA total of 103 adults with severe sepsis or septic shock on ICU admission were randomised (54 subjects in the experimental arm and 49 subjects in the control arm).InterventionsHaemodynamic management using an algorithm that was adapted from the 2004 Surviving Sepsis Campaign guidelines with (experimental arm) or without (control arm) targeting an StO2 value greater than 80% at a minimum of two different sites.OutcomesThe primary outcome was a composite: 7-day all-cause mortality or worsening of organ function, defined as a positive difference in Sepsis-related Organ Failure Assessment (SOFA) score between day 7 and randomisation (ie, delta SOFA >0). Secondary endpoints: 30-day mortality, duration of mechanical ventilation and vasopressor therapy up to 30 days from randomisation.ResultsThe study ended prematurely due to lack of funding after enrolment of 103/190 patients. Eighteen patients (33.3%) in the experimental arm and 14 (28.6%, P=0.67) in the control arm died or exhibited delta SOFA >0 on day 7. The mean number of days on mechanical ventilation was 12.2±10.6 in the experimental group and 7.6±7.9 in the control group (P=0.03). Thirty-one (57%) patients in the experimental arm and 14 (29%) patients in the control arm received red cells by day 7 (P=0.01).ConclusionDespite the limitation related to premature termination, this study provides no data to support the routine implementation of resuscitation protocols incorporating StO2 >80% at two or more muscle sites as a target. StO2-guided therapy may be associated with prolonged use of mechanical ventilation and an increased number of red blood cell transfusions.Trial registration number NCT00167596; Results.
We identified a set of propofol and remifentanil TCIs that blocked the gag response to endoscope insertion in patients undergoing endoscopy. Propofol bolus doses and remifentanil infusion rates designed to achieve similar effect-site concentrations can be used to prevent gag response when TCI is not available.
Respiratory depression is a common adverse effect of propofol and remifentanil. We aimed to develop a model for respiratory depressant effects of propofol with remifentanil in patients undergoing endoscopy with sedation. Data were available for 136 patients undergoing endoscopy with sedation. Participants randomly received infusions of propofol and remifentanil. Predicted plasma concentrations, outputted by infusion pumps, were available. Transcutaneous arterial pressure of carbon dioxide (pCO 2 ) was measured. Data were analyzed using nonlinear mixed-effects modeling methods. Covariate relationships were investigated for age, noxious stimuli (endoscopy tube insertion), and A118G genotype for the m-opioid receptor (OPRM1). Participants had a median ( An indirect-effect model with a "modulator" compartment best described pCO 2 data (P , 0.001) over a direct-effect model. Remifentanil inhibited pCO 2 removal with an IC 50 of 1.13 ng/ml and first-order rate constant (k e0 ) of 0.28 minute 21. Propofol affected the modulator compartment with an IC 50 of 4.97 mg/ml (no effect-site compartment). Propofol IC 50 and remifentanil k e0 were reduced with increasing age. Noxious stimuli and genotype were not significant covariates. An indirect-effect model with a rebound mechanism can describe remifentanil-and propofolinduced changes in pCO 2 in patients undergoing noxious procedures. The model may be useful for identifying optimal dosing schedules for these drugs in a combination that provides adequate sedation but avoids respiratory depression.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.