Definition of hourly urine output influences reported incidence and staging of acute kidney injury

© 2020 The Author(s). Background: Acute kidney injury (AKI) is commonly defined using the KDIGO system, which includes criteria based on reduced urine output (UO). There is no consensus on whether UO should be measured using consecutive hourly readings or mean output. This makes KDIGO UO definition and staging of AKI vulnerable to inconsistency which has implications both for research and clinical practice. The objective of this study was to investigate whether the way in which UO is defined affects incidence and staging of AKI. Methods: We conducted a retrospective analysis of two single centre observational studies investigating (i) patients undergoing cardiac surgery and (ii) patients admitted to general intensive care units (ICU). AKI was identified using KDIGO serum creatinine (SCr) criteria and two methods of UO (UOcons: UO meeting KDIGO criteria in each consecutive hour; UOmean: Mean hourly UO meeting KDIGO criteria). Results: Data from 151 CICU and 150 ICU admissions were analysed. Incidence of AKI using SCr alone was 23.8% in CICU and 32% in ICU. Incidence increased in both groups when UO was considered, with inclusion of UOmean more than doubling reported incidence of AKI (CICU: UOcons 39.7%, UOmean 72.8%; ICU: UOcons 51.3%, UOmean 69.3%). In both groups UOcons led to a larger increase in KDIGO stage 1 but UOmean increased the incidence of KDIGO stage 2. Conclusions: We demonstrate a serious lack of clarity in the internationally accepted AKI definition leading to significant variability in reporting of AKI incidence

Self-reported depression symptoms in haemodialysis patients: Bi-factor structures of two common measures and their association with clinical factors

Copyright © 2018 Elsevier Inc. All rights reserved.Objective: To validate the factor structure of two common self-report depression tools in a large sample of haemodialysis (HD) patients and to examine their demographic and clinical correlates, including urine output, history of depression and transplantation. Methods: Factor structures of the Beck Depression Inventory (BDI-II) and Patient Health Questionnaire (PHQ-9) were evaluated using confirmatory factor analysis (CFA). Data was utilised from the screening phase (n = 709) of a placebo-controlled feasibility randomised control trial (RCT) of sertraline in HD patients with mild to moderate Major Depressive Disorder. Alternative factor models including bi-factor models for the BDI-II and PHQ-9 were evaluated. Coefficient omega and omega-hierarchical were calculated. Results: For both measures, bi-factor measurement models had the overall best fit to the data, with dominant general depression factors. Omega-hierarchical for the general BDI-II and PHQ-9 factors was 0.94 and 0.88 respectively. Both general factors had high reliability (coefficient omega = 0.97 and 0.94 respectively) and explained over 85% of the explained common variance within their respective models. BDI-II and PHQ-9 general depression factors were negatively associated with age and urine output and positively with a history of depression, antidepressant use within the last 3 months and a history of failed transplantation. In adjusted regression models, age, urine output and a history of depression remained significant. Conclusions: These data suggest that both the BDI-II and PHQ-9 are sufficiently unidimensional to warrant the use of a total score. Younger age, lower urine output and a history of depression appear consistent correlates of depression severity among HD patients.Peer reviewedFinal Accepted Versio

Automated drug identification system

System speeds up analysis of blood and urine and is capable of identifying 100 commonly abused drugs. System includes computer that controls entire analytical process by ordering various steps in specific sequences. Computer processes data output and has readout of identified drugs

Understanding urine output in critically ill patients

Urine output often is used as a marker of acute kidney injury but also to guide fluid resuscitation in critically ill patients. Although decrease of urine output may be associated to a decrease of glomerular filtration rate due to decrease of renal blood flow or renal perfusion pressure, neurohormonal factors and functional changes may influence diuresis and natriuresis in critically ill patients. The purpose of this review is to discuss the mechanisms of diuresis regulation, which may help to interpret the urine output in critically ill patients and the appropriate treatment to be initiated in case of changes in urine output

Postobstructive diuresis in cats with naturally occurring lower urinary tract obstruction: incidence, severity and association with laboratory parameters on admission

Objectives The objectives of this retrospective study were to investigate the actual incidence of postobstructive diuresis after relief of urethral obstruction in cats, as well as to identify changes in blood and urine parameters that might be associated with postobstructive diuresis (POD), and to assess the impact of fluid therapy. Methods The medical records of 57 male cats with urethral obstruction that were treated with an indwelling urinary catheter were retrospectively analysed. Absolute urine output in ml/kg/h every 4 h and the incidence of cats with polyuria (urine volume >2 ml/kg/h) at any time point over a 48 h period after the re-establishment of urine flow were investigated. In addition, postobstructive diuresis in relation to fluid therapy (PODFR) was defined as urine output greater than the administered amount of intravenous fluids on at least two subsequent time points. Polyuria and PODFR were investigated for their association with blood and urine laboratory parameters. Results After 4 h, 74.1% (40/54) of the cats had polyuria, with a urine output of >2 ml/kg/h. Metabolic acidosis was present in 46.2% of the cats. Venous blood pH and bicarbonate were inversely correlated with urine output in ml/kg/h after 4 h. The overall incidence of POD within 48 h of catheterisation was 87.7%. There was a significant correlation between intravenous fluid rate at time point x and urine output at time point x + 1 at all the time points except for the fluid rate at time point 0 and the urine output after 4 h. PODFR was seen in 21/57 cats (36.8%). Conclusions and relevance POD is a frequent finding in cats treated for urethral obstruction, and can be very pronounced. Further studies are required to determine whether or not a change in venous blood pH actually interferes with renal concentrating ability. The discrepancy between the frequency of cats with polyuria and PODFR (87.7% vs 36.8%) in the present study indicates that administered intravenous fluid therapy might be the driving force for the high incidence of polyuria in some cats with naturally occurring obstructive feline lower urinary tract disease

Pengaruh Pemberian Loading 500 Cc Hidroxylethyl Starch 130/0,4 (6%) Terhadap Produksi Urin Pada Anestesi Spinal Pasien Sectio Caesaria

Background. Spinal anesthesia in caesar surgery lead to reduction of blood pressure and uroplacenta circulation. Hypotension alone will decrease Glomerulus Filtration Rate (GFR), causing low urine production. Administration of crystalloid fluid is not too effective to prevent lowering of blood pressure. Loading 500 cc HES 130/0.4 are expected to be more effective because it has longer intravascular effect.Objective. This research aims to prove the effect of loading 500 cc HES 130/0.4 towards the urine output of caesarean patients with spinal anesthesia.Method. This research is observational, using cross sectional as it\u27s base of design. Samples collected from 27 medical record that fulfill the inclusion and exlusion criteria. Samples are pateints who receive loading of 500 cc Hydroxylethyl starch 130/0.4 (6%) before spinal anesthesia in caesarean patients. Urine output is noted in 15,30,60 and 120 minutes. Research is done in medical record installations and IBS dr. Kariadi Semarang.Result. Mean volume of urine output have a significant decrease between 15 minutes with 35,93 ml to 30 minutes (21,11 ml), 60 minutes (11,48 ml), and 120 minutes (29,11).Conclusion. A significant decrease in volume of urine output before and after administration of HES 130/0.4 (6%) is noted, but still within normal limits

Dose of colistin. a work in progress?

We thank Rashid and colleagues [1] and Honoré and colleagues [2] for their comments regarding our article on risk factors for acute kidney injury in pa- tients receiving colistin or other nephrotoxic antimi- crobials [3]. It is correct that we did not specifically report urine output in the text, but it was obviously included in the RIFLE (Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease) criteria reported in Table two [3]

A Novel Patient-Specific Model for Predicting Severe Oliguria; Development and Comparison With Kidney Disease: Improving Global Outcomes Acute Kidney Injury Classification

Objectives: The Kidney Disease: Improving Global Outcomes urine output criteria for acute kidney injury lack specificity for identifying patients at risk of adverse renal outcomes. The objective was to develop a model that analyses hourly urine output values in real time to identify those at risk of developing severe oliguria. Design: This was a retrospective cohort study utilizing prospectively collected data. Setting: A cardiac ICU in the United Kingdom. Patients: Patients undergoing cardiac surgery between January 2013 and November 2017. Interventions: None. Measurement and Main Results: Patients were randomly assigned to development (n = 981) and validation (n = 2,389) datasets. A patient-specific, dynamic Bayesian model was developed to predict future urine output on an hourly basis. Model discrimination and calibration for predicting severe oliguria ( 0.8) were identified and their outcomes were compared with those for low-risk patients and for patients who met the Kidney Disease: Improving Global Outcomes urine output criterion for acute kidney injury. Model discrimination was excellent at all time points (area under the curve > 0.9 for all). Calibration of the model’s predictions was also excellent. After adjustment using multivariable logistic regression, patients in the high-risk group were more likely to require renal replacement therapy (odds ratio, 10.4; 95% CI, 5.9–18.1), suffer prolonged hospital stay (odds ratio, 4.4; 95% CI, 3.0–6.4), and die in hospital (odds ratio, 6.4; 95% CI, 2.8–14.0) (p < 0.001 for all). Outcomes for those identified as high risk by the model were significantly worse than for patients who met the Kidney Disease: Improving Global Outcomes urine output criterion. Conclusions: This novel, patient-specific model identifies patients at increased risk of severe oliguria. Classification according to model predictions outperformed the Kidney Disease: Improving Global Outcomes urine output criterion. As the new model identifies patients at risk before severe oliguria develops it could potentially facilitate intervention to improve patient outcomes

A Low Cost Device for Monitoring the Urine Output of Critical Care Patients

In critical care units most of the patients’ physiological parameters are sensed by commercial monitoring devices. These devices can also supervise whether the values of the parameters lie within a pre-established range set by the clinician. The automation of the sensing and supervision tasks has discharged the healthcare staff of a considerable workload and avoids human errors, which are common in repetitive and monotonous tasks. Urine output is very likely the most relevant physiological parameter that has yet to be sensed or supervised automatically. This paper presents a low cost patent-pending device capable of sensing and supervising urine output. The device uses reed switches activated by a magnetic float in order to measure the amount of urine collected in two containers which are arranged in cascade. When either of the containers fills, it is emptied automatically using a siphon mechanism and urine begins to collect again. An electronic unit sends the state of the reed switches via Bluetooth to a PC that calculates the urine output from this information and supervises the achievement of therapeutic goals

Investigating Novel Biomarkers Associated with AKI Diagnosis and Risk

Acute kidney injury (AKI) is a common complication associated with cardiac surgery. Those patients who develop AKI have increased hospital costs, hospital LOS and odds of death. The current diagnostic criteria rely on serum creatinine measurements and urine output data. Serum creatinine is not renal specific. It is known that there are other factors that influence serum creatine concentrations other than renal injury. Serum creatinine levels are measured as concentrations which means large changes in fluid balance may alter the serum creatinine measurement. Urine output is not a reliable measurement of renal injury either. During surgery it is common to administer diuretics which influence urine output independent of renal damage. Researchers are investigating novel biomarkers that are renal specific and can monitor AKI risk in real time. Some researchers are focused on identifying chemical biomarkers to diagnose AKI more effectively. Preliminary studies have also shown that urine oxygen concentration may be a physiological biomarker that can be used to monitor AKI risk in real time. Urine oxygen concentration may reflect tissue oxygen concentration in the medullary region of the kidney. The aim of this study was to investigate the relationship between urine biomarker concentrations, urine oxygen concentration and AKI diagnosis. The results from this study suggest that is possible to monitor oxygen concentration non-invasively and it could potentially be used to monitor AKI risk in real time