Focus on oliguria during renal replacement therapy.

Oliguria is a clinical symptom characterized by decreased urine output, which can occur at any stage of acute kidney injury and also during renal replacement therapy. In some cases, oliguria may resolve with adjustment of blood purification dose or fluid management, while in others, it may suggest a need for further evaluation and intervention. It is important to determine the underlying cause of oliguria during renal replacement therapy and to develop an appropriate treatment plan. This review looks into the mechanisms of urine production to investigate the mechanism of oliguria during renal replacement therapy from two aspects: diminished glomerular filtration rate and tubular abnormalities. The above conditions all implying a renal oxygen supply-demand imbalance, which is the signal of worsening kidney injury. It also proposes a viable clinical pathway for the treatment and management of patients with acute kidney injury receiving renal replacement therapy.

CCL14 Predicts Oliguria and Dialysis Requirement in Patients with Moderate to Severe Acute Kidney Injury.

INTRODUCTION: AKI is a frequent complication of critical illness and portends poor outcome. CCL14 is a validated predictor of persistent severe AKI in critically ill patients. We examined the association of CCL14 with urine output within 48 h. METHODS: In pooled data from 2 studies of critically ill patients with KDIGO stage 2-3 AKI, CCL14 was measured by NEPHROCLEAR™ CCL14 Test on the Astute 140® Meter (low, intermediate, and high categories [1.3 and 13 ng/mL]). Average hourly urine output over 48 h, stage 3 AKI per urine output criterion on day 2, and composite of dialysis or death within 7 days were examined using multivariable mixed and logistic regression models. RESULTS: Of the 497 subjects with median age of 65 (56-74) years, 49% (242/497) were on diuretics. CCL14 concentration was low in 219 (44%), intermediate in 217 (44%), and high in 61 (12%) patients. In mixed regression analysis, hourly urine output over time was different within each CCL14 risk category based on diuretic use due to significant three-way interaction (p < 0.001). In logistic regression analysis, CCL14 risk category was independently associated with low urine output on day 2 per KDIGO stage 3 (adjusted for diuretic use and baseline clinical variables), and composite of dialysis or death within 7 days (adjusted for urine output within 48 h of CCL14 measurement). CONCLUSIONS: CCL14 measured in patients with moderate to severe AKI is associated with urine output trajectory within 48 h, oliguria on day 2, and dialysis within 7 days.

How a positive fluid balance develops in acute kidney injury: A binational, observational study.

PURPOSE: A positive fluid balance (FB) is associated with harm in intensive care unit (ICU) patients with acute kidney injury (AKI). We aimed to understand how a positive balance develops in such patients. METHODS: Multinational, retrospective cohort study of critically ill patients with AKI not requiring renal replacement therapy. RESULTS: AKI occurred at a median of two days after admission in 7894 (17.3%) patients. Cumulative FB became progressively positive, peaking on day three despite only 848 (10.7%) patients receiving fluid resuscitation in the ICU. In those three days, persistent crystalloid use (median:60.0 mL/h; IQR 28.9-89.2), nutritional intake (median:18.2 mL/h; IQR 0.0-45.9) and limited urine output (UO) (median:70.8 mL/h; IQR 49.0-96.7) contributed to a positive FB. Although UO increased each day, it failed to match input, with only 797 (10.1%) patients receiving diuretics in ICU. After adjustment, a positive FB four days after AKI diagnosis was associated with an increased risk of hospital mortality (OR 1.12;95% confidence intervals 1.05-1.19;p-value <0.001). CONCLUSION: Among ICU patients with AKI, cumulative FB increased after diagnosis and was associated with an increased risk of mortality. Continued crystalloid administration, increased nutritional intake, limited UO, and minimal use of diuretics all contributed to positive FB. KEY POINTS: Question How does a positive fluid balance develop in critically ill patients with acute kidney injury? Findings Cumulative FB increased after AKI diagnosis and was secondary to persistent crystalloid fluid administration, increasing nutritional fluid intake, and insufficient urine output. Despite the absence of resuscitation fluid and an increasing cumulative FB, there was persistently low diuretics use, ongoing crystalloid use, and a progressive escalation of nutritional fluid therapy. Meaning Current management results in fluid accumulation after diagnosis of AKI, as a result of ongoing crystalloid administration, increasing nutritional fluid, limited urine output and minimal diuretic use.

Precursors to oliguria during major burn resuscitation: An analysis of a prospective observational trial at 5 major US burn centers.

Currently, urine output is the leading variable used to tailor fluid resuscitation in patients with large TBSA burns. However, this metric often lags with respect to resuscitation. Our group sought to identify derangements in variables that precede development of oliguria (<30 cc/hr) that we hypothesize will aid in more efficient resuscitation. We performed a retrospective analysis of 146 adult patients admitted within 4 h of a large TBSA (>20%) burn. We then divided them into two cohorts: those who developed oliguria within 6 h of admission and those who did not. Patients who experienced early oliguria had a higher incidence of invasive SBP < 90 (p = 0.02) or DBP < 40 (p = 0.009), lower minimum bicarbonate level (p = 0.04), more full thickness burns (p = 0.004), and higher TBSA (p = 0.01). More female patients were found in the oliguric group (p = 0.003). Multivariate analysis was used to develop a model to predict development of oliguria. When evaluated together, minimum DBP, sex, TBSA (or percent full thickness burn), and maximum base deficit constituted the most parsimonious model that significantly predicted oliguria (AUC = 0.92). Interestingly, the model lost significance when DBP was omitted, highlighting the importance of diastolic pressure in the development of oliguria.

Initial lactate levels linked to oliguria in term neonates with perinatal asphyxia.

BACKGROUND: Oliguria is a sign of impaired kidney function and has been shown to be an early predictor of adverse prognoses in patients with acute kidney injury. The relationship between urine output (UOP) and early lactate levels in neonates with perinatal asphyxia (PA) has not been extensively explored. This study aimed to investigate the link between oliguria during the first 24 h of life and early lactate levels in neonates with PA. METHODS: The medical records of 293 term neonates with asphyxia from 9216 hospitalized newborns were retrospectively analyzed, including 127 cases designated as the oliguria group and 166 cases as controls. Peripheral arterial blood gas after PA and UOP within 24 h after birth were analyzed. Logistic regression analyses and receiver operating characteristic curve analysis were conducted. RESULTS: Oliguria occurred in 43.34% of neonates with PA. The median UOP of the oliguria and control groups were 0.65 and 1.46 mL/kg/h, respectively. Elevated lactate levels after PA are an independent risk factor for oliguria in the following 24 h (p = 0.01; OR: 1.19; 95%CI: 1.04-1.35) and show a moderate discriminatory power for oliguria (AUC = 0.62). Using a cut off value of 8.15 mmol/L, the positive and negative predictive values and the specificity were 59.34%, 63.86%, and 78.30%, respectively. CONCLUSION: Neonates with elevated lactate levels after PA face a risk of oliguria in the following 24 h. Based on early elevated lactate levels after resuscitation, especially ≥ 8.15 mmol/L, meticulously monitoring UOP will allow this vulnerable population to receive early, tailored fluid management and medical intervention.

Retrospective evaluation of 22 dogs with leptospirosis treated with extracorporeal renal replacement therapies (2018-2021).

BACKGROUND: Outcomes of dogs with acute kidney injury secondary to leptospirosis (AKI-L) treated using renal replacement therapies (RRT) are poorly characterized. HYPOTHESIS/OBJECTIVES: Describe survival to discharge, short (≤30 days) and long-term (≥6 months) outcomes of AKI-L dogs receiving RRT and determine if there is a significant difference in maximum blood urea nitrogen (maxBUN), maximum creatinine (maxCr), maximum bilirubin (maxBili) and the number of body systems affected between survivors and non-survivors. ANIMALS: Twenty-two client-owned dogs with AKI-L receiving RRT. METHODS: Retrospective medical record review of dogs with AKI-L that received RRT between 2018 and 2021. RESULTS: Sixteen of 22 (73%) dogs survived to discharge. Of the survivors, 13 (81%) were alive >30 days from discharge and 12 (75%) were alive at 6 months from discharge. Factors significantly higher in non-survivors included number of body systems affected (survivors: 1 (19%), 2 (50%), 3 (25%) and 4 (6%) vs non-survivors: 3 (33.3%), and 4 (66.7%); P = .01) and median maxBili (survivors: 1.9 mg/dL; range, 0.1-41.6 vs non-survivors: 21.0 mg/dL; range, 12.3-38.9; P = .02). There was no significant difference in median maxBUN (survivors: 153.0 mg/dL; range, 67-257 vs non-survivors: 185.5 mg/dL; range, 102-218; P = .44) and median maxCr (survivors: 9.8 mg/dL; range, 6.2-15.9 vs non-survivors: 9.8 mg/dL; range, 8.4-13.5; P = .69) between survivors and non-survivors. CONCLUSIONS AND CLINICAL IMPORTANCE: Regardless of azotemia severity, dogs with AKI-L receiving RRT have a good survival rate to discharge. The number of body systems affected and hyperbilirubinemia might be associated with worse outcomes.

Neurodevelopment After Neonatal Acute Kidney Injury in Very Preterm-Birth Children.

Introduction: This study aimed to assess head circumference (HC) growth and neurodevelopmental outcomes in very preterm-birth children after neonatal acute kidney injury (AKI). Methods: This longitudinal follow-up cohort included 732 very preterm neonates of gestational age <31 weeks admitted to a tertiary center between 2008 and 2020. AKI was categorized as nonoliguric and oliguric AKI based on the urine output criteria during admission. We compared the differences in death, z scores of HC (zHC) at term-equivalent age (TEA) and at corrected ages of 6, 12, and 24 months, and the neurodevelopmental outcomes at corrected age of 24 months after neonatal nonoliguric and oliguric AKI. Results: Among the 154 neonates who developed AKI, 72 had oliguric AKI and 82 had nonoliguric AKI. At TEA, oliguric AKI, but not nonoliguric AKI, was independently associated with lower zHC than non-AKI (mean differences, -0.49; 95% confidence interval [CI], -0.92 to -0.06). Although the 3 groups were comparable in zHC at corrected ages of 6, 12, and 24 months, the oliguric AKI group, but not the nonoliguric AKI group, had a higher rate of microcephaly by corrected age of 24 months. In addition, the oliguric AKI group, but not the nonoliguric AKI group, was more likely to die (61% vs. 9%) and have neurodevelopmental impairment (41% vs. 14%) compare with the non-AKI group. After adjustment, oliguric (adjusted odds ratio [aOR], 8.97; 95% CI, 2.19-36.76), but not nonoliguric, AKI was associated with neurodevelopmental impairment. Conclusion: Neonatal oliguric AKI is associated with neurodevelopmental impairment in very preterm-birth children. Long-term head-size and neurodevelopmental follow-up after neonatal AKI is warranted.

Urine output as one of the most important features in differentiating in-hospital death among patients receiving extracorporeal membrane oxygenation: a random forest approach.

BACKGROUND: It is common to support cardiovascular function in critically ill patients with extracorporeal membrane oxygenation (ECMO). The purpose of this study was to identify patients receiving ECMO with a considerable risk of dying in hospital using machine learning algorithms. METHODS: A total of 1342 adult patients on ECMO support were randomly assigned to the training and test groups. The discriminatory power (DP) for predicting in-hospital mortality was tested using both random forest (RF) and logistic regression (LR) algorithms. RESULTS: Urine output on the first day of ECMO implantation was found to be one of the most predictive features that were related to in-hospital death in both RF and LR models. For those with oliguria, the hazard ratio for 1 year mortality was 1.445 (p < 0.001, 95% CI 1.265-1.650). CONCLUSIONS: Oliguria within the first 24 h was deemed especially significant in differentiating in-hospital death and 1 year mortality.

Identifying risk factors and disease severity in leptospirosis: A meta-analysis of clinical predictors.

Leptospirosis is a bacterial zoonosis with a wide spectrum of clinical presentations. In order to identify potential risk factors and predictors of disease severity, a meta-analysis of the clinical features of severe and non-severe leptospirosis patients was conducted. PubMed was searched to collect studies on the difference in clinical characteristics of severe and nonsevere patients, and data were analyzed using Comprehensive Meta-Analysis V3 software. Results showed that patients with severe outcomes were more likely to have dyspnoea, oliguria, and hemorrhagic symptoms than nonsevere patients. Determining these predictors in the early stages of the disease could thus significantly reduce the development of severe cases and related mortality.

Tocilizumab Associated With Survival in Patients Hospitalized for COVID-19 Acute Respiratory Distress Syndrome and Low Urine Output.

BACKGROUND: Acute respiratory distress syndrome (ARDS) with oliguria is associated with increased mortality. Interleukin-6 (IL-6) plays an integral role in the pathophysiology of both disease processes. Patients who experience severe COVID-19 have demonstrated higher IL-6 levels compared to baseline, and use of tocilizumab has demonstrated efficacy in such cohorts. We set out to investigate the relationship between tocilizumab use, COVID-19 ARDS, low urine output, and mortality. METHODS: Retrospective cohort review of adult patients aged ≥ 18 years with COVID-19 and moderate or severe ARDS, admitted to the intensive care unit (ICU) of a tertiary referral center in metropolitan Detroit. Patients were analyzed based on presence of oliguria (defined as ≤ 0.7 mL/kg/h) on the day of intubation and exposure to tocilizumab while inpatient. The primary outcome was inpatient mortality. RESULTS: One hundred and twenty-eight patients were analyzed, 103 (80%) with low urine output, of whom 30 (29%) received tocilizumab. In patients with low urine output, risk factors associated with mortality on univariate analysis included Black race (P = .028), lower static compliance (P = .015), and tocilizumab administration (P = .002). Tocilizumab (odds ratio 0.245, 95% confidence interval 0.079-0.764, P = .015) was the only risk factor independently associated with survival on multivariate logistic regression analysis. CONCLUSION: In this retrospective cohort review of patients hospitalized with COVID-19 and moderate or severe ARDS, tocilizumab administration was independently associated with survival in patients with low urine output ≤ 0.7 mL/kg/h on the day of intubation. Prospective studies are needed to investigate the impact of urine output on efficacy of interleukin-targeted therapies in the management of ARDS.

Identification of an optimal threshold to define oliguria in critically ill patients: an observational study.

BACKGROUND: The relevance of current consensus threshold to define oliguria has been challenged by small observational studies. We aimed to determine the optimal threshold to define oliguria in critically-ill patients. METHODS: Cohort study including adult patients admitted within a multi-disciplinary intensive care unit between January 1st 2010 and June 15th 2020. Patients on chronic dialysis or who declined consent were excluded. We extracted hourly urinary output (UO) measurements along with patient's characteristics from electronic medical records and 90-day mortality from the Swiss national death registry. We randomly split our data into a training (80%) and a validation (20%) set. In the training set, we developed multivariable models to assess the relationship between 90-day mortality and the minimum average UO calculated over time windows of 3, 6, 12 and 24 h. Optimal thresholds were determined by visually identifying cut-off values for the minimum average UO below which predicted mortality increased substantially. We tested models' discrimination and calibration on the entire validation set as well as on a subset of patients with oliguria according to proposed thresholds. RESULTS: Among the 15,500 patients included in this analysis (training set: 12,440, validation set: 3110), 73.0% (95% CI [72.3-73.8]) presented an episode of oliguria as defined by consensus criteria (UO < 0.5 ml/kg/h for 6 h). Our models had excellent (AUC > 85% for all time windows) discrimination and calibration. The relationship between minimum average UO and predicted 90-day mortality was nonlinear with an inflexion point at 0.2 ml/kg/h for 3 and 6 h windows and 0.3 ml/kg/h for 12 and 24 h windows. Considering a threshold of < 0.2 ml/kg/h over 6 h, the proportion of patients with an episode of oliguria decreased substantially to 24.7% (95% CI [24.0-25.4]). Contrary to consensus definition, this threshold identified a population with a higher predicted 90-day mortality. CONCLUSIONS: The widely used cut-off for oliguria of 0.5 ml/kg/h over 6 h may be too conservative. A cut-off of 0.2 ml/kg/h over 3 or 6 h is supported by the data and should be considered in further definitions of oliguria.

Early detection of oliguric events in critically ill patients in the ICU with a novel continuous urine flow measurement device: results of an initial validation study.

OBJECTIVES: Urine output is used to evaluate fluid status and is an important marker for acute kidney injury (AKI). Our primary aim was to validate a new automatic urine output monitoring device by comparison to the current practice - the standard urometer. METHODS: We conducted a prospective observational study in three ICUs. Urine flow measurements by Serenno Medical Automatic urine output measuring device (Serenno Medical, Yokneam, Israel) were compared to standard urometer readings taken automatically at 5-minutes intervals by a camera, and to hourly urometer readings by the nurses, both over 1 to 7 days. Our primary outcome was the difference between urine flow assessed by the Serenno device and reference camera-derived measurements (Camera). Our secondary outcome was the difference between urine flow assessed by the Serenno device and hourly nursing assessments (Nurse), and detection of oliguria. RESULTS: Thirty-seven patients completed the study, with 1,306 h of recording and a median of 25 measurement hours per patient. Bland and Altman analysis comparing the study device to camera measurements demonstrated good agreement, with a bias of -0.4 ml/h and 95% confidence intervals ranging from - 28 to 27ml/h. Concordance was 92%. The correlation between Camera and hourly nursing assessment of urine output was distinctly worse with a bias of 7.2 ml and limits of agreement extending from - 75 to + 107 ml. Severe oliguria (urine output < 0.3 ml/kg/h) lasting 2 h or more was common and observed in 8 (21%) of patients. Among the severe oliguric events lasting more than 3 consecutive hours, 6 (41%) were not detected or documented by the nursing staff. There were no device-related complications. CONCLUSION: The Serenno Medical Automatic urine output measuring device required minimal supervision, little ICU nursing staff attention, and is sufficiently accurate and precise. In addition to providing continuous assessments of urine output, it was considerably more accurate than hourly nursing assessments.

The role of the bladder diary in phenotyping men with LUTS.

AIMS: The aim of this study was to compare the clinical characteristics of men with lower urinary tract symptoms (LUTS) grouped by 24-h urine output determined from a bladder voiding diary. METHODS: An online database was queried to identify men who completed a 24-hour bladder diary (24HBD), and the Lower Urinary Tract Symptom Score (LUTSS) questionnaire from 2015 to 2019 using a mobile app. Data from the bladder diary and questionnaire were contemporaneously matched within a 2-week period. Additional data, including maximum uroflow (Qmax ) and postvoid residual urine (PVR), were obtained from the electronic medical record (EMR). The cohort was divided into three groups: normal, oliguria, and polyuria based on their 24-hour voided volume (24HVV). The LUTSS, 24HVV, maximum voided volume (MVV), maximum flow rate (Qmax ), and PVR were compared between those with oliguria and polyuria. RESULTS: A total of 327 men (mean age 62, SD: 19) completed the LUTSS questionnaire and contemporaneous 24HBD. Of these, 61% had a normal 24HVV, 13% had oliguria, and 26% had polyuria. A total of 147 patients from the study cohort had contemporaneous Qmax and PVR abstracted from the EMR. There was no difference in symptom severity, bother, or PVR among the three patient groups. However, several objective metrics were significantly correlated with urine output. Men with oliguria, as compared to men with polyuria were older (65 vs. 55 years) and had lower MVV (260 vs. 470 mL), fewer voids/24 h (8 vs. 13), and lower Qmax (8.5 vs. 18.3 mL/s). CONCLUSIONS: These observations suggest that men with oliguria or polyuria and LUTS constitute easily distinguished phenotypes that might require different diagnostic and therapeutic algorithms. Those with oliguria were older, and had lower MVVs and much lower uroflows, suggesting that they are more likely to have underlying disorders such as bladder outlet obstruction and detrusor underactivity or may be patients with overactive bladder who reduced fluid intake to improve symptoms.

Association between intraoperative oliguria and postoperative acute kidney injury in non-cardiac surgical patients: a systematic review and meta-analysis.

PURPOSE: This systematic review and meta-analysis aimed to evaluate the association between intraoperative oliguria and the risk of postoperative acute kidney injury (AKI) in patients undergoing non-cardiac surgery. METHODS: The MEDLINE and EMBASE databases were searched up to August 2022 for studies in adult patients undergoing non-cardiac surgery, where the association between intraoperative urine output and the risk of postoperative AKI was assessed. Both randomised and non-randomised studies were eligible for inclusion. Study selection and risk of bias assessment were independently performed by two investigators. The risk of bias was evaluated using the Newcastle-Ottawa scale. We performed meta-analysis of the reported multivariate adjusted odds ratios for the association between intraoperative oliguria (defined as urine output < 0.5 mL/kg/hr) and the risk of postoperative AKI using the inverse-variance method with random effects models. We conducted sensitivity analyses using varying definitions of oliguria as well as by pooling unadjusted odds ratios to establish the robustness of the primary meta-analysis. We also conducted subgroup analyses according to surgery type and definition of AKI to explore potential sources of clinical or methodological heterogeneity. RESULTS: Eleven studies (total 49,252 patients from 11 observational studies including a post hoc analysis of a randomised controlled trial) met the selection criteria. Seven of these studies contributed data from a total 17,148 patients to the primary meta-analysis. Intraoperative oliguria was associated with a significantly elevated risk of postoperative AKI (pooled adjusted odds ratio [OR] 1.74; 95% confidence interval [CI] 1.36-2.23, p < 0.0001, 8 studies). Sensitivity analyses supported the robustness of the primary meta-analysis. There was no evidence of any significant subgroup differences according to surgery type or definition of AKI. CONCLUSIONS: This study demonstrated a significant association between intraoperative oliguria and the risk of postoperative AKI, regardless of the definitions of oliguria or AKI used. Further prospective and multi-centre studies using standardised definitions of intraoperative oliguria are required to define the thresholds of oliguria and establish strategies to minimise the risk of AKI.

Non-interventional follow-up versus fluid bolus in RESPONSE to oliguria in hemodynamically stable critically ill patients: a randomized controlled pilot trial.

BACKGROUND: Fluid bolus therapy is a common intervention to improve urine output. Data concerning the effect of a fluid bolus on oliguria originate mainly from observational studies and remain controversial regarding the actual benefit of such therapy. We compared the effect of a follow-up approach without fluid bolus to a 500 mL fluid bolus on urine output in hemodynamically stable critically ill patients with oliguria at least for 2 h (urine output < 0.5 mL/kg/h) in randomized setting. METHODS: We randomized 130 patients in 1:1 fashion to receive either (1) non-interventional follow-up (FU) for 2 h or (2) 500 mL crystalloid fluid bolus (FB) administered over 30 min. The primary outcome was the proportion of patients who doubled their urine output, defined as 2-h urine output post-randomization divided by urine output 2 h pre-randomization. The outcomes were adjusted for the stratification variables (presence of sepsis or AKI) using two-tailed regression. Obtained odds ratios were converted to risk ratios (RR) with 95% confidence intervals (CI). The between-group difference in the continuous variables was compared using mean or median regression and expressed with 95% CIs. RESULTS: Altogether 10 (15.9%) of 63 patients in the FU group and 22 (32.8%) of 67 patients in FB group doubled their urine output during the 2-h period, RR (95% CI) 0.49 (0.23-0.71), P = 0.026. Median [IQR] change in individual urine output 2 h post-randomization compared to 2 h pre-randomization was - 7 [- 19 to 17] mL in the FU group and 19[0-53] mL in the FB group, median difference (95% CI) - 23 (- 36 to - 10) mL, P = 0.001. Median [IQR] duration of oliguria in the FU group was 4 [2-8] h and in the FB group 2 [0-6] h, median difference (95%CI) 2 (0-4) h, P = 0.038. Median [IQR] cumulative fluid balance on study day was lower in the FU group compared to FB group, 678 [518-1029] mL versus 1071 [822-1505] mL, respectively, median difference (95%CI) - 387 (- 635 to - 213) mL, P < 0.001. CONCLUSIONS: Follow-up approach to oliguria compared to administering a fluid bolus of 500 mL crystalloid in oliguric patients improved urine output less frequently but lead to lower cumulative fluid balance. Trial registration clinical. TRIALS: gov, NCT02860572. Registered 9 August 2016.

Improving awareness of kidney function through electronic urine output monitoring: a comparative study.

BACKGROUND: The current classification for acute kidney injury (AKI) according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria integrates both serum creatinine (SCr) and urine output (UO). Most reports on AKI claim to use KDIGO guidelines but fail to include the UO criterion. It has been shown that patients who had intensive UO monitoring, with or without AKI, had significantly less cumulative fluid volume and fluid overload, reduced vasopressor use, and improved 30-day mortality. We examined whether real-time monitoring of this simple, sensitive, and easy-to-use biomarker in the ICU led to more appropriate intervention by healthcare providers and better outcomes.  METHODS: RenalSense Clarity RMS Consoles were installed in the General ICU at the Hadassah Medical Center, Israel, from December 2019 to November 2020. The Clarity RMS system continuously and electronically monitors UO in real-time. 100 patients were randomly selected from this period as the study group (UOelec) and compared to a matched control group (UOmanual) from the same period two years earlier. To test whether there was an association between oliguric hours and fluid treatment in each group, the correlation was calculated and analyzed for each of the different UO monitoring methods. RESULTS: Therapeutic intervention: The correlation of the sum of all oliguric hours on Day 1 and 2 with the sum of any therapeutic intervention (fluid bolus or furosemide) showed a significant correlation for the study group UOelec (P = 0.017). The matched control group UOmanual showed no such correlation (P = 0.932). Length of Stay (LOS): Median LOS [IQR] in the ICU of UOelec versus UOmanual was 69.46 [44.7, 125.9] hours and 116.5 [62.46, 281.3] hours, respectively (P = 0.0002). CONCLUSIONS: The results of our study strongly suggest that ICU patients had more meaningful and better medical intervention, and improved outcomes, with electronic UO monitoring than with manual monitoring.

Effects of an intravenous infusion of diltiazem on glomerular filtration rate, electrolyte excretion, and urine output in healthy dogs.

BACKGROUND: Acute kidney injury (AKI) in dogs has a high case fatality rate. Diltiazem might improve renal function, but effect of intravenous infusion has not been adequately studied in dogs. HYPOTHESIS/OBJECTIVES: To determine if an intravenous infusion of diltiazem improves renal function through changes in glomerular filtration rate (GFR), fractional excretion of sodium (FENa), and urine output (UOP) in healthy dogs. ANIMALS: Ten healthy adult dogs. METHODS: Prospective, unmasked, crossover study. Dogs were randomized to receive diltiazem (loading dose of 240 µg/kg followed by 6 µg/kg/min for 300 min) or the same volume of 5% dextrose in water (D5W). The opposite treatment was given after a 7-day washout period. GFR and FENa were obtained at baseline and after infusion. UOP was measured starting 1 hour before diltiazem administration. RESULTS: GFR did not significantly increase from baseline with diltiazem (before diltiazem median = 2.371 mL/min/kg, range = 1.605-4.359; after diltiazem median = 2.305 mL/min/kg, range = 1.629-4.387; median difference = 0.080 mL/min/kg, 95% confidence interval [CI] = -0.417 to 0.757; P = .85), and there was no difference in D5W GFR before and after diltiazem (median = 2.389 mL/min/kg, range = 1.600-3.557; median difference = 0.036 mL/min/kg, 95% CI = -0.241 to 1.112; P = .69). FENa did not increase from baseline after administration of diltiazem (median difference = 0%, 95% CI = -0.1 to 0.1; P = .81), and there was no difference in D5W FENa (median difference = 0.1%, 95% CI = -0.1 to 0.2; P = .26). UOP did not increase with diltiazem (P = .06). CONCLUSION AND CLINICAL IMPORTANCE: Intravenous administration of diltiazem does not improve markers of renal function in healthy dogs. Further studies are needed in dogs with AKI.

Integrating network pharmacology and experimental verification to explore the mechanism of puerarin against oliguria in acute alcoholism.

Purpose: This study was designed to evaluate the pharmacological mechanisms of puerarin against oliguria in acute alcoholism via network pharmacology analysis combined with experimental verification. Methods: First, this study established an acute alcoholism rat model, compared the changes in urine volume in each group, and observed the therapeutic effect of puerarin by H&E staining, biochemical, RT-qPCR, and immunohistochemical analyses. Second, puerarin-related targets were searched in TCMS, PubChem, CNKI, Wanfang, PubMed, and GeenMedical Academic databases. Also, potential disease targets were obtained from the GeneCards, MalaCards, and NCBI-gene databases and genes with puerarin target gene intersections were screened out. The interaction network for co-predicted targets was obtained using the STRING database, and the core targets were imported into Cytoscape for visualization using DAVID Bioinformatics Resources 6.8. The essential genes were subjected to the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) pathway enrichment analyses to predict related biological processes and significant signaling pathways. Finally, molecular docking was used to examine the interaction of puerarin with key targets, and the core targets were validated further by RT-qPCR and Western blotting. Results: Compared to the model group, the urine volume of the rats was significantly increased after puerarin treatment, and the levels of anti-diuretic hormone (ADH) and aquaporin 2 (AQP2) expression were decreased. Searching the intersection of puerarin and acute alcoholism targets yielded 214 potential targets, 837 biological processes, and 185 signaling pathways involved. The molecular docking results indicated a good affinity between puerarin and key targets (cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), cAMP-response element-binding protein (CREB), and c-Fos). RT-qPCR and Western blotting further verified that puerarin could down-regulate the expression of cAMP/PKA/CREB/c-Fos. Conclusion: This study identified the potential targets of puerarin against oliguria in rats with acute alcoholism using network pharmacology and animal experiments. The mechanism may be closely related to the cAMP signaling pathway.

Clinicopathological features and short outcomes of oliguric acute tubular injury.

PURPOSE: To explore the clinicopathological features and analyze the relevant risk factors and short-term renal outcomes of acute tubular injury (ATI) patients. MATERIALS AND METHODS: A total of 83 patients with biopsy-proven ATI were included in this retrospective cohort study. Clinical characteristic and histological feature data were collected, and renal recovery at 1 month postbiopsy was recorded. RESULTS: The severity of renal dysfunction, percentage of acute tubular lesions, interstitial inflammation and fibrosis of oliguric ATI patients were all significantly higher than those of nonoliguric patients. In the subgroup analysis of the oliguric patients, the serum creatinine and urinary microalbumin levels, severity of epithelial cell degeneration and cast formation of patients in the polyuric phase at biopsy were significantly lower than those of patients in the oliguric phase. A total of 59 patients had 1-month follow-up records, and complete renal recovery was observed in 42 patients. In the multivariate analysis, the total acute tubular injury area at biopsy was the most important independent risk factor for poor renal outcomes. CONCLUSIONS: Oliguric ATI patients had severe clinicopathological conditions. The severity of tubular lesions seriously influenced renal function recovery, demonstrating the importance of renal biopsy in assessing the prognosis of patients with kidney disease.

Atypical hemolytic uremic syndrome after myomectomy: A case report.

Atypical hemolytic uremic syndrome (aHUS) is a rare form of thrombotic microangiopathy due to inability to regulate the complement cascade, resulting in thrombocytopenia, intravascular hemolysis, and end-organ damage. Over 70% of cases are associated with mutations in complement or complement regulatory proteins, and some two-thirds have recognized complement-activating conditions triggering an aHUS event. We describe a case of aHUS after abdominal myomectomy in a 42-year-old woman that was managed with plasma exchange and eculizumab (an anti-C5 monoclonal antibody). The diagnosis was confirmed by biopsy of normal-appearing deltoid skin that demonstrated microvascular C5b-9 deposition, diagnostic of systemic complement pathway activation. Although extremely uncommon following gynecologic surgery, aHUS should be considered in the setting of postoperative oliguric acute kidney injury, as prompt diagnosis is necessary to prevent significant morbidity and mortality.