Kirsten Colpaert

Impact of real-time electronic alerting of acute kidney injury on therapeutic intervention and progression of RIFLE class

Objective:To evaluate whether a real-time electronic alert system or “AKI sniffer,” which is based on the RIFLE classification criteria (Risk, Injury and Failure), would have an impact on therapeutic interventions and acute kidney injury progression. Design:Prospective intervention study. Setting:Surgical and medical intensive care unit in a tertiary care hospital. Patients:A total of 951 patients having in total 1,079 admission episodes were admitted during the study period (prealert control group: 227, alert group: 616, and postalert control group: 236). Interventions:Three study phases were compared: A 1.5-month prealert control phase in which physicians were blinded for the acute kidney injury sniffer and a 3-month intervention phase with real-time alerting of worsening RIFLE class through the Digital Enhanced Cordless Technology telephone system followed by a second 1.5-month postalert control phase. Measurements and Main Results:A total of 2593 acute kidney injury alerts were recorded with a balanced distribution over all study phases. Most acute kidney injury alerts were RIFLE class risk (59.8%) followed by RIFLE class injury (34.1%) and failure (6.1%). A higher percentage of patients in the alert group received therapeutic intervention within 60 mins after the acute kidney injury alert (28.7% in alert group vs. 7.9% and 10.4% in the pre- and postalert control groups, respectively, p &mgr; .001). In the alert group, more patients received fluid therapy (23.0% vs. 4.9% and 9.2%, p &mgr; .01), diuretics (4.2% vs. 2.6% and 0.8%, p &mgr; .001), or vasopressors (3.9% vs. 1.1% and 0.8%, p &mgr; .001). Furthermore, these patients had a shorter time to intervention (p &mgr; .001). A higher proportion of patients in the alert group showed return to a baseline kidney function within 8 hrs after an acute kidney injury alert “from normal to risk” compared with patients in the control group (p = .048). Conclusions:The real-time alerting of every worsening RIFLE class by the acute kidney injury sniffer increased the number and timeliness of early therapeutic interventions. The borderline significant improvement of short-term renal outcome in the RIFLE class risk patients needs to be confirmed in a large multicenter trial. (Crit Care Med 2012; 40:–1170)

Development and validation of a model for prediction of mortality in patients with acute burn injury

The objective was to develop a user‐friendly model to predict the probability of death from acute burns soon after injury, based on burned surface area, age and presence of inhalation injury.

Outcome of acute kidney injury in severe burns: a systematic review and meta-analysis

PurposeThe main objective of this review was to analyse the prevalence and outcome of acute kidney injury (AKI) in patients with severe burn injury. AKI is a common complication in patients with severe burn injury and one of the major causes of death (often combined with other organ dysfunctions). Several definitions of AKI have been used, but the RIFLE ‘consensus’ classification is nowadays considered the gold standard, enabling a more objective comparison of populations.MethodsWe performed a systematic literature search (1960–2009), involving PubMed, the Web of Science, the search engine Google™ and textbooks. Reference lists and the Science Citation Index search were also consulted. Attributable mortality was assessed by performing a meta-analysis.ResultsThis search yielded 57 articles and abstracts with relevant epidemiologic data of AKI in the burn population. Of these, 30 contained complete mortality data of the burn and control population, which revealed a 3- to 6-fold higher mortality for AKI patients in univariate analysis, depending on the applied definition. When defined by the RIFLE consensus classification, AKI occurred in one quarter of patients with severe burn injury (median mortality of 34.9%), and when defined by the need for renal replacement therapy (RRT), AKI occurred in 3% (median mortality of 80%). The prevalence of AKI slightly increased, but AKI-RRT decreased. However, the outcome in both groups improved.ConclusionDespite the wide variation of the analysed burn populations and definitions of AKI, this review clearly showed that AKI remains prevalent and is associated with increased mortality in patients with severe burn injury.

Daily cost of antimicrobial therapy in patients with Intensive Care Unit-acquired, laboratory-confirmed bloodstream infection

This study analysed daily antimicrobial costs of Intensive Care Unit (ICU)-acquired, laboratory-confirmed bloodstream infection (BSI) per patient admitted to the ICU of a university hospital, based on prospectively collected data over a 4-year period (2003-2006). Costs were calculated based on the price of the agent(s) initiated on the first day of appropriate treatment and according to: (i) focus of infection; (ii) pathogen; and (iii) antimicrobial agent. The study included 310 adult patients who developed 446 BSI episodes. Mean overall daily antimicrobial cost was euro114.25. Daily antimicrobial cost was most expensive for BSIs with unknown focus (euro137.70), followed by catheter-related (euro122.73), pulmonary (euro112.80), abdominal (euro98.00), wound (euro89.21), urinary (euro87.85) and other inciting focuses (euro81.59). Coagulase-negative staphylococci were the most prevalent pathogens isolated. Treatment of BSIs caused by Candida spp. was the most costly. The daily antimicrobial costs per infected patient with multidrug-resistant BSI was ca. 50% higher compared with those without (euro165.09 vs. euro82.67; P<0.001). Among the total of 852 prescriptions, beta-lactam antibiotics accounted for approximately one-third of the overall daily cost of antimicrobial agents. The antibiotic cost associated with ICU-acquired, laboratory-confirmed BSI is significant and should be reduced by implementing infection control measures and preventive strategies.

Augmented renal clearance is a common finding with worse clinical outcome in critically ill patients receiving antimicrobial therapy

INTRODUCTION We describe incidence and patient factors associated with augmented renal clearance (ARC) in adult intensive care unit (ICU) patients. MATERIALS AND METHODS A prospective observational study in a mixed cohort of surgical and medical ICU patients receiving antimicrobial therapy at the Ghent University Hospital, Belgium. Kidney function was assessed by the 24-hour creatinine clearance (Ccr); ARC defined as at least one Ccr of >130 mL/min per 1.73 m2. Multivariate logistic regression analysis: to assess variables associated with ARC occurrence. Therapeutic failure (TF): an impaired clinical response and need for alternate antimicrobial therapy. RESULTS Of the 128 patients and 599 studied treatment days, ARC was present in 51.6% of the patients. Twelve percent permanently expressed ARC. ARC patients had a median Ccr of 144 mL/min per 1.73 m2 (IQR 98-196). Median serum creatinine concentration on the first day of ARC was 0.54 mg/dL (IQR 0.48-0.69). Patients with ARC were significantly younger (P<.001). Age and male gender were independently associated with ARC whereas the APACHE II score was not. ARC patients had more TF (18 (27.3%) vs. 8 (12.9%); P=.04). CONCLUSION ARC was documented in approximately 52% of a mixed ICU patient population receiving antibiotic treatment with worse clinical outcome. Young age and male gender were independently associated with ARC presence.

Pharmacokinetics of fluoroquinolones in critical care patients: A bio-analytical HPLC method for the simultaneous quantification of ofloxacin, ciprofloxacin and moxifloxacin in human plasma.

A high-performance liquid chromatographic (HPLC) method with fluorescence detection was developed and validated for the simultaneous quantification of ofloxacin, ciprofloxacin and moxifloxacin in human plasma. Sarafloxacin was used as internal standard. Chromatography was carried out using a Waters XBridge C(18) HPLC column and a gradient mobile phase consisting of CH(3)CN/MeOH/0.025M TBA.Cl/TFA (eluent A at 75/25/899/1 (v/v); eluent B at 150/50/799/1 (v/v); both at pH 3.5). Excitation/emission wavelengths were 279/442nm for ciprofloxacin and 290/500nm for ofloxacin, moxifloxacin and internal standard. Prior to chromatography, plasma samples were treated with acetonitrile for protein precipitation, followed by evaporation of the liquid layer and reconstitution in eluent A. The method was validated for the three fluoroquinolones over the clinically relevant concentration range from 0.02 to 7.50mug/ml. The method showed acceptable linearity with correlation coefficients, r(2)>0.995, as well as high precision (RSD% <7% in each case), accuracy (90.4-105.4%) and selectivity. The limit of quantification for the three fluoroquinolones was established at 0.02mug/ml. Ofloxacin, ciprofloxacin and moxifloxacin were extracted from plasma with a mean recovery of 95%, 86.4% and 94.2%, respectively. During validation, the concentration of the three fluoroquinolones was found to be stable after 3 freeze-thaw cycles and for at least 15h after extraction. This bio-analytical method was finally applied to the analysis of samples which have been obtained from patients, participating in a pharmacokinetic study on moxifloxacin.

COSARA: Integrated Service Platform for Infection Surveillance and Antibiotic Management in the ICU

The Intensive Care Unit is a data intensive environment where large volumes of patient monitoring and observational data are daily generated. Today, there is a lack of an integrated clinical platform for automated decision support and analysis. Despite the potential of electronic records for infection surveillance and antibiotic management, different parts of the clinical data are stored across databases in their own formats with specific parameters, making access to all data a complex and time-consuming challenge. Moreover, the motivation behind physicians’ therapy decisions is currently not captured in existing information systems. The COSARA research project offers automated data integration and services for infection control and antibiotic management for Ghent University Hospital. The platform not only gathers and integrates all relevant data, it also presents the information visually at the point of care. In this paper, we describe the design and value of COSARA for clinical treatment and infectious diseases monitoring. On the one hand, this platform can facilitate daily bedside follow-up of infections, antibiotic therapies and clinical decisions for the individual patient, while on the other hand, the platform serves as management view for infection surveillance and care quality improvement within the complete ICU ward. It is shown that COSARA is valuable for registration, real-time presentation and management of infection-related and antibiotics data.

Towards computerizing intensive care sedation guidelines: design of a rule-based architecture for automated execution of clinical guidelines

BackgroundComputerized ICUs rely on software services to convey the medical condition of their patients as well as assisting the staff in taking treatment decisions. Such services are useful for following clinical guidelines quickly and accurately. However, the development of services is often time-consuming and error-prone. Consequently, many care-related activities are still conducted based on manually constructed guidelines. These are often ambiguous, which leads to unnecessary variations in treatments and costs.The goal of this paper is to present a semi-automatic verification and translation framework capable of turning manually constructed diagrams into ready-to-use programs. This framework combines the strengths of the manual and service-oriented approaches while decreasing their disadvantages. The aim is to close the gap in communication between the IT and the medical domain. This leads to a less time-consuming and error-prone development phase and a shorter clinical evaluation phase.MethodsA framework is proposed that semi-automatically translates a clinical guideline, expressed as an XML-based flow chart, into a Drools Rule Flow by employing semantic technologies such as ontologies and SWRL. An overview of the architecture is given and all the technology choices are thoroughly motivated. Finally, it is shown how this framework can be integrated into a service-oriented architecture (SOA).ResultsThe applicability of the Drools Rule language to express clinical guidelines is evaluated by translating an example guideline, namely the sedation protocol used for the anaesthetization of patients, to a Drools Rule Flow and executing and deploying this Rule-based application as a part of a SOA. The results show that the performance of Drools is comparable to other technologies such as Web Services and increases with the number of decision nodes present in the Rule Flow. Most delays are introduced by loading the Rule Flows.ConclusionsThe framework is an effective solution for computerizing clinical guidelines as it allows for quick development, evaluation and human-readable visualization of the Rules and has a good performance. By monitoring the parameters of the patient to automatically detect exceptional situations and problems and by notifying the medical staff of tasks that need to be performed, the computerized sedation guideline improves the execution of the guideline.

Service-oriented Subscription Management of Medical Decision Data in the Intensive Care Unit

OBJECTIVES This paper addresses the design of a platform for the management of medical decision data in the ICU. Whenever new medical data from laboratories or monitors is available or at fixed times, the appropriate medical support services are activated and generate a medical alert or suggestion to the bedside terminal, the physicians PDA, smart phone or mailbox. Since future ICU systems will rely ever more on medical decision support, a generic and flexible subscription platform is of high importance. METHODS Our platform is designed based on the principles of service-oriented architectures, and is fundamental for service deployment since the medical support services only need to implement their algorithm and can rely on the platform for general functionalities. A secure communication and execution environment are also provided. RESULTS A prototype, where medical support services can be easily plugged in, has been implemented using Web service technology and is currently being evaluated by the Department of Intensive Care of the Ghent University Hospital. To illustrate the platform operation and performance, two prototype medical support services are used, showing that the extra response time introduced by the platform is less than 150 ms. CONCLUSIONS The platform allows for easy integration with hospital information systems. The platform is generic and offers user-friendly patient/service subscription, transparent data and service resource management and priority-based filtering of messages. The performance has been evaluated and it was shown that the response time of platform components is negligible compared to the execution time of the medical support services.

Acute kidney injury in burns: a story of volume and inflammation

Acute kidney injury occurs in approximately one-quarter to one-third of patients with major burn injury. Apart from the usual suspects – such as older age, severity of burn injury, sepsis and multiple organ dysfunction – volume overload probably has an important role in the pathogenesis of acute kidney injury.