18 research outputs found
The Theory of Fuzzy Logic and its application to Real Estate Valuation
Fuzzy logic is based on the central idea that in fuzzy sets each element in the set can assume a value from 0 to 1, not just 0 or 1, as in classic set theory. Thus, qualitative characteristics and numerically scaled measures can exhibit gradations in the extent to which they belong to the relevant sets for evaluation. This degree of membership of each element is a measure of the elementโs "belonging" to the set, and thus of the precision with which it explains the phenomenon being evaluated. Fuzzy sets can be combined to produce meaningful conclusions, and inferences can be made, given a specified fuzzy input function. The article demonstrates the application of fuzzy logic to an income-producing property, with a resulting fuzzy set output
Beta-Lactam Infusion in Severe Sepsis (BLISS): a prospective, two-centre, open-labelled randomised controlled trial of continuous versus intermittent beta-lactam infusion in critically ill patients with severe sepsis
This study aims to determine if continuous infusion (CI) is associated with better clinical and pharmacokinetic/pharmacodynamic (PK/PD) outcomes compared to intermittent bolus (IB) dosing in critically ill patients with severe sepsis.
This was a two-centre randomised controlled trial of CI versus IB dosing of beta-lactam antibiotics, which enrolled critically ill participants with severe sepsis who were not on renal replacement therapy (RRT). The primary outcome was clinical cure at 14 days after antibiotic cessation. Secondary outcomes were PK/PD target attainment, ICU-free days and ventilator-free days at day 28 post-randomisation, 14- and 30-day survival, and time to white cell count normalisation.
A total of 140 participants were enrolled with 70 participants each allocated to CI and IB dosing. CI participants had higher clinical cure rates (56 versus 34 %, p = 0.011) and higher median ventilator-free days (22 versus 14 days, p MIC than the IB arm on day 1 (97 versus 70 %, p < 0.001) and day 3 (97 versus 68 %, p < 0.001) post-randomisation. There was no difference in 14-day or 30-day survival between the treatment arms.
In critically ill patients with severe sepsis not receiving RRT, CI demonstrated higher clinical cure rates and had better PK/PD target attainment compared to IB dosing of beta-lactam antibiotics. Continuous beta-lactam infusion may be mostly advantageous for critically ill patients with high levels of illness severity and not receiving RRT
Polyene antifungals
Determining the optimal polyene antifungal dosing in obese patients is considered highly challenging. Limited data are available to describe the pharmacokinetics of polyene antifungals in these patients. However, polyene antifungals demonstrate widely variable pharmacokinetics in various clinical conditions. In particular, the two main parameters that define dosing requirements, volume of distribution (V) and clearance, can change significantly in obese patients. Therefore, in the absence of robust data to describe optimal polyene dosing in obesity, dosing guided by therapeutic drug monitoring (TDM) remains the best approach, particularly when aggressive dosing is required in the context of poorly susceptible pathogens. Lean body weight appears to be the preferred weight metric to estimate polyene dosing in obesity, in order to prevent inappropriate excessive doses and subsequent adverse events including nephrotoxicity
Understanding the impact of pathophysiological alterations during critical illness on drug pharmacokinetics
The impact of variation in renal replacement therapy settings on piperacillin, meropenem, and vancomycin drug clearance in the critically ill: an analysis of published literature and dosing regimens
Objectives: To describe the effect of different renal replacement therapy modalities and settings on the clearance of meropenem, piperacillin, and vancomycin in critically ill patients and to evaluate the frequency with which current dosing regimens achieve therapeutic concentrations
Improving antibiotic dosing in special situations in the ICU: burns, renal replacement therapy and extracorporeal membrane oxygenation
Purpose of revie
Interethnic differences in pharmacokinetics of antibacterials
Background Optimal antibacterial dosing is imperative for maximising clinical outcome. Many factors can contribute to changes in the pharmacokinetics of antibacterials to the extent where dose adjustment may be needed. In acute illness, substantial changes in important pharmacokinetic parameters such as volume of distribution and clearance can occur for certain antibacterials. The possibility of interethnic pharmacokinetic differences can further complicate attempts to design an appropriate dosing regimen. Factors of ethnicity, such as genetics, body size and fat distribution, contribute to differences in absorption, distribution, metabolism and elimination of drugs. Despite extensive previous work on the altered pharmacokinetics of antibacterials in some patient groups such as the critically ill, knowledge of interethnic pharmacokinetic differences for antibacterials is limited
How can we ensure effective antibiotic dosing in critically ill patients receiving different types of renal replacement therapy?
Determining appropriate antibiotic dosing for critically ill patients receiving renal replacement therapy (RRT) is complex. Worldwide unstandardized and heterogeneous prescribing of RRT as well as altered patient physiology and pathogen susceptibility all cause drug disposition to be much different to that seen in non-critically ill patients. Significant changes to pharmacokinetic parameters, including volume of distribution and clearance, could be expected, in particular, for antibiotics that are hydrophilic with low plasma protein binding and that are usually primarily eliminated by the renal system. Antibiotic clearance is likely to be significantly increased when higher RRT intensities are used. The combined effect of these factors that alter antibiotic disposition is that non-standard dosing strategies should be considered to achieve therapeutic exposure. In particular, an aggressive early approach to dosing should be considered and this may include administration of a 'loading dose', to rapidly achieve therapeutic concentrations and maximally reduce the inoculum of the pathogen. This approach is particularly important given the pharmacokinetic changes in the critically ill as well as the increased likelihood of less susceptible pathogens. Dose individualization that applies knowledge of the RRT and patient factors causing altered pharmacokinetics remains the key approach for ensuring effective antibiotic therapy for these patients. Where possible, therapeutic drug monitoring should also be used to ensure more accurate therapy. A lack of pharmacokinetic data for antibiotics during the prolonged intermittent RRT and intermittent hemodialysis currently limits evidence-based antibiotic dose recommendations for these patients. (C) 2015 Elsevier Inc. All rights reserved
A national survey of renal replacement therapy prescribing practice for acute kidney injury in Malaysian intensive care units
Objectives To describe renal replacement therapy (RRT) prescribing practices in Malaysian intensive care units (ICU), and compare this with previously published data from other regions. Method A survey was sent to physicians responsible for prescribing RRT in major ICU throughout Malaysia. The questionnaire sought information on the physicians' background, and detailed information regarding RRT settings. Results Nineteen physicians from 24 sites throughout Malaysia responded to the survey (response rate 79.2%). Sixteen respondents were intensivists (84%), 2 were anaesthetists (11%) and one was a nephrologist (5%). The majority (58%) used continuous venovenous haemofiltration (CVVH) as the treatment of choice for acute kidney injury (AKI) in critically ill patients. RRT prescription was predominantly practitioner-dependent (63%), while 37% reported use of a dedicated protocol. The mean blood flow rate and effluent flow rate used for continuous RRT (CRRT) were 188.9 ยฑ 28.9 mL/min and 30.6 ยฑ 4.7 mL/kg/h respectively. Replacement fluid solutions containing both lactate and bicarbonate were commonly used during CRRT, applied both pre- and post-dilution. Conclusion CRRT was the first-choice modality used to treat AKI in critically ill patients. CVVH was the most common CRRT technique used, while other RRT modalities were used less frequently. Overall, RRT practices were similar to those observed in other regions, although the modality and settings used were slightly different, likely due to local availability