Estimation of urinary volume through ultrasonography in dog cadavers and experimental models.

The urinary volume and residual urine volume are pieces of information that can provide relevant clinical data for dogs and cats, especially those hospitalized. Thus, the present study aimed to evaluate mathematical formulas described in human and veterinary literature to estimate urinary volume in dogs and experimental models. For this purpose, nine male dog cadavers and twelve experimental models were used to evaluate residual volume, small, medium, and large, using three different formulas. Data were obtained by three different examiners: two ultrasonographers and one nonultrasonographer. Each examiner recorded three longitudinal and transverse images, obtaining measurements of width, length, and height at each proposed volume. The measurements were then averaged, and the result was added to the formulas, thus estimating urinary volume. All three formulas achieved higher accuracy in estimating smaller volumes, with a gradual decrease as urinary volume increased. The error of all formulas was less than 10%, even when compared with evaluations in experimental models and dogs. There was variation in estimation between ultrasonographers and nonultrasonographer examiners; however, this variation was low, allowing for the assertion that both can apply the technique. Thus, it is concluded that estimating urinary bladder volume using mathematical formulas and 2D ultrasound is accurate and, therefore, an alternative and viable option for evaluating the urinary tract.

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.

Effect of Furosemide on Urinary Oxygenation in Patients with Septic Shock.

BACKGROUND: Renal medullary hypoxia precedes the development of acute kidney injury in experimental sepsis and can now be assessed by continuous measurement of urinary oxygen tension (PuO2). OBJECTIVES: We aimed to test if PuO2 measurements in patients with septic shock would be similar to those shown in experimental sepsis and would detect changes induced by the administration of furosemide. METHOD: Pilot prospective observational cohort study in a tertiary intensive care unit (ICU). Seven adult patients with septic shock admitted to ICU had PuO2 measurements recorded minutely. There were 29 episodes of intravenous furosemide (20 mg n = 19; 40 mg n = 10). RESULTS: The median pre-furosemide PuO2 was low at 21.2 mm Hg (interquartile range [IQR] 17.73-24.86) and increased to 26 mm Hg (IQR 20.27-29.95) at 20 min (p < 0.01), to 27.5 mm Hg (IQR 24.06-33.18) at 40 min (p < 0.01) and to 28.5 mm Hg (IQR 22.65-31.03) at 60 min (p < 0.01). The increase in PuO2 was greater in episodes with a diuretic response >2 mL/kg/h than during episodes without such a response (p < 0.01). CONCLUSIONS: PuO2 measurements in patients are reflective of the low values reported in experimental models of sepsis. PuO2 values increased following furosemide administration with a response independently associated with greater diuresis.

The prognostic value of the furosemide stress test in predicting delayed graft function following deceased donor kidney transplantation.

OBJECTIVES AND METHODS: The Furosemide Stress Test (FST) is a novel dynamic assessment of tubular function that has been shown in preliminary studies to predict patients who will progress to advanced stage acute kidney injury, including those who receive renal replacement therapy (RRT). The aim of this study is to investigate if the urinary response to a single intraoperative dose of intravenous furosemide predicts delayed graft function (DGF) in patients undergoing deceased donor kidney transplant. RESULTS: On an adjusted multiple logistic regression, a single 100 mg dose of intraoperative furosemide after the anastomosis of the renal vessels (FST) predicted the need for RRT at 2 and 6 h post kidney transplantation (KT). Recipient urinary output was measured at 2 and 6 h post furosemide administration. In receiver-operating characteristic (ROC) analysis, the FST predicted DGF with an area-under-the curve of 0.85 at an optimal urinary output cut-off of <600 mls at 6 h with a sensitivity of and a specificity of 83% and 74%, respectively. CONCLUSIONS: The FST is a predictor of DGF post kidney transplant and has the potential to identify patients requiring RRT early after KT.

Assessment of hemodynamic response to fluid resuscitation of patients with intra-abdominal sepsis in low- and middle-income countries.

BACKGROUND: Patients with intra-abdominal infections need to achieve adequate hemodynamic status before being taken to the operating room. Multiple parameters (urinary output [UOP], vital signs, inferior vena cava collapsibility index, and central venous pressure) may be used to assess hemodynamic response to fluid resuscitation, but the options are few in limited-resource settings. This study aimed at assessing if a bedside-performed ultrasound to assess the inferior vena cava collapsibility index is superior to UOP in assessing hemodynamic response to fluid resuscitation. METHODS: All adult patients presenting to a tertiary referral hospital in the capital city of Rwanda with intra-abdominal infection requiring intravenous fluid (IVF) resuscitation before operation were included in this study. Before IVF administration, the baseline inferior vena cava collapsibility index (IVC-CI) and vital parameters were recorded. After initiation of IVF resuscitation, serial measurements of IVC-CI and UOP were recorded every 2 h until the decision was made to take the patient to the operating room. RESULTS: Twenty-four patients were enrolled. The mean duration of symptoms was 4.7 days. Four patients (16%) had altered mental status as a presenting symptom. Half of all patients had generalized peritonitis due to gangrenous bowel as the primary diagnosis (n = 12). The mean difference between time of hemodynamic response based on IVC-CI versus UOP was 2 h (P < 0.001). CONCLUSIONS: Measurement of the IVC-CI can provide early detection of hemodynamic response to fluid therapy in patients with intra-abdominal infection with spontaneous breathing compared to UOP. Future research should utilize this parameter in the preoperative management of hemodynamically unstable patients.

Assessment of the Diuretic Properties of Rice Bean Accessions Using a Mouse Model and Identification of Active Polyphenolic Compounds.

Rice bean [Vigna umbellata (Thunb.) Ohwi and Ohashi], an annual legume in the genus Vigna, is a promising crop suitable for cultivation in a changing climate to ensure food security. It is also a medicinal plant widely used in traditional Chinese medicine; however, little is known about the medicinal compounds in rice bean. In this study, we assessed the diuretic effect of rice bean extracts on mice as well as its relationship with the contents of eight secondary metabolites in seeds. Mice gavaged with rice bean extracts from yellow and black seeds had higher urinary output (5.44-5.47 g) and water intake (5.8-6.3 g) values than mice gavaged with rice bean extracts from red seeds. Correlation analyses revealed significant negative correlations between urine output and gallic acid (R = -0.70) and genistein (R = -0.75) concentrations, suggesting that these two polyphenols negatively regulate diuresis. There were no obvious relationships between mice diuresis-related indices (urine output, water intake, and weight loss) and rutin or catechin contents, although the concentrations of both of these polyphenols in rice bean seeds were higher than the concentrations of the other six secondary metabolites. Our study findings may be useful for future research on the diuretic effects of rice bean, but they should be confirmed on the basis of systematic medical trials.

Continuous Monitoring of Intra-abdominal Pressure in Severe Acute Pancreatitis Leads to Early Detection of Abdominal Compartment Syndrome: A Case Report.

Acute pancreatitis is a risk factor for intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS). Immediate detection and management of IAH and ACS are critical for patient survival. Obtaining accurate and consistent intra-abdominal pressure and urinary output with high frequency is challenging, but critical for effective patient management. The presented case is of a 40-year-old man with a history of chronic alcoholism who developed severe acute pancreatitis. The patient was fluid resuscitated for distributive shock; hypoxic respiratory failure, intubation, and anuria followed. Real-time monitoring of urinary output and intra-abdominal pressure (IAP) allowed for early recognition of acute kidney injury (AKI) and ACS leading to early surgical intervention. Normalized IAP returned renal function and re-establishment of stable hemodynamics without vasopressors.

Effect of remifentanil on intraoperative fluid balance: a retrospective statistical examination of factors contributing to fluid balance.

BACKGROUND: Postoperative fluid retention is a factor that causes delay in recovery and unexpected adverse events. It is important to prevent intraoperative fluid retention, which is putatively caused by intraoperative release of stress hormones, such as ADH (anti-diuretic hormone) or others. We hypothesized that intraoperative analgesia may prevent pathological fluid retention. We retrospectively explored the relationship between analgesics and in-out balance in surgical patients from anesthesia records. METHODS: Anesthetic records of 80 patients who had undergone orthognathic surgery were checked in this study. Patients were anesthetized with either TIVA (propofol and remifentanil) or inhalational anesthesia (sevoflurane and remifentanil). During surgery, acetated Ringer's solution was infused for maintenance at a rate of 3-5 ml/kg/h at the discretion of the anesthetist. The perioperative parameters, including the amount of crystalloid and colloid infused, and the amount of urine and bleeding were checked. Furthermore, we checked the amount and administration rate of remifentanil during the surgical procedure. The correlation coefficient between the remifentanil dose and the in-out balance or the urinary output was analyzed using the Pearson correlation coefficient. The contributing factor to fluid retention, including urinary output, was statistically examined by means of multivariate logistic regression analysis. RESULTS: A significant positive correlation was found between remifentanil dose and urinary output. Urinary output less than 0.04 ml/kg/min was suggested to cause positive fluid balance. Although in-out balance approaches zero balance with increase in remifentanil administration rate, no contributing factor for near-zero fluid balance was statistically picked up. The remifentanil administration rate was statistically picked up as the significant factor for higher urinary output (> 0.04 ml/kg/min) (OR, 2,644; 95% CI, 3.2-2.2 × 106) among perioperative parameters. CONCLUSIONS: In conclusion, remifentanil contributes in maintaining the urinary output during general anesthesia. Although further prospective study is needed to confirm this hypothesis, it was suggested that fluid retention could be avoided through suppressing intraoperative stress response by means of appropriate maintenance of remifentanil infusion rate.

Acute kidney injury management using intermittent low efficiency haemodiafiltration in a critical care unit: 39 dogs (2012-2015).

BACKGROUND: Veterinary studies describing acute kidney injury (AKI) management using renal replacement therapy (RRT) are limited and have primarily focused on intermittent haemodialysis in North American populations. European data are lacking, although differences in populations, pathogen and toxin exposure and RRT modalities may exist between Europe and North America. The present study reviewed RRT-managed cases from the intensive care unit (ICU) of VetAgro Sup, Lyon, France, for the period 2012-2015. The aims were to describe a 4-h RRT protocol of intermittent low efficiency haemodiafiltration, population characteristics and outcomes in canine AKI cases requiring RRT and to identify prognostic variables. We defined DeltaCreat/h as the difference between the serum creatinine level after RRT treatment N and that before treatment N + 1 divided by the time between treatments (in hours). RESULTS: Thirty-nine dogs were included, and 67% were males. The median (range) age, weight, hospitalization length and number of RRT treatments were 4.4 (0.25-15) years, 26.6 (6.7-69) kg, 8 (1-23) days and 3 (1-8) treatments, respectively. The main AKI causes were leptospirosis (74.4%) and nephrotoxins (15.4%). Age (4.0 vs 5.4 years; P = 0.04), admission urine output (0.5 mL/kg/h vs 0 mL/kg/h; P = 0.02) and hospitalization length (10 vs 4 days; P < 0.001) differed between survivors and non-survivors. Hospitalization length [odds ratio (OR) = 0.4], number of treatments (OR = 5.1), serum potassium level on day 2 (OR = 1.9), DeltaCreat/h between the first and second treatments (OR = 1.2), and UOP during hospitalization (OR = 0.2) were correlated with outcome. The main causes of death were euthanasia (44%) and haemorrhagic diatheses (33%). The overall survival rate was 54%, with 55% of survivors discharged with a median creatinine < 240 µmol/L. CONCLUSIONS: This is the first description in the veterinary literature of a 4-h protocol of intermittent low efficiency haemodiafiltration to provide RRT in a veterinary critical care unit. While this protocol appears promising, the clinical application of this protocol requires further investigation. Among parameters associated with survival, UOP and DeltaCreat/h between the first and second RRT treatments may be prognostic indicators. The applicability of these parameters to other populations is unknown, and further international, multicentre prospective studies are warranted to confirm these preliminary observations.

Clinical and laboratory markers in the recovery from severe preeclampsia.

OBJECTIVE: To examine the recovery from severe Preeclampsia toxemia (PET) in women treated with magnesium sulfate (MgSO4) during the first 24h postpartum as reflected by the changes in various clinical and laboratory markers. STUDY DESIGN: The study population included all women diagnosed with severe PET that gave birth at the Soroka University Medical center between 2013 and 2014, and were treated with MgSO4 in the first 24h postpartum. Data were collected from the institutional computerized records. The different parameters were examined in 6h intervals and were compared using appropriate statistical tests. MAIN OUTCOMES MEASURES: Change in various postpartum laboratory and clinical parameters. RESULTS: During the study period there were 132 singleton deliveries with severe PET treated with a 24-hours postpartum MgSO4 regimen. Most of the women were primigravida and delivered vaginally. Both mean systolic and mean diastolic blood pressure values have shown recovery to normal values after the first 6h of treatment (P<0.001). Urine output and proteinuria have demonstrated later recovery (after 12h). CONCLUSIONS: When assessing the natural recovery of severe PET features, the earliest parameter to recover during the first 24h postpartum is hypertension followed by urine output and the proteinuria. Further larger studies are needed in order to confirm these results. Moreover, the use of these parameters may allow using shorter MgSO4 treatment regimens for appropriate women showing earlier recovery and facilitating quicker mother-baby bonding and emotional recovery.

Acute Kidney Injury Risk Factors For ICU Patients Following Cardiac Surgery: The Application of Joint Modeling.

BACKGROUND: Admission to the ICU (intensive care unit) is frequently complicated by early AKI (acute kidney injury). The development of AKI following cardiac surgery is particularly associated with increased mortality and morbidity. According to AKIN (acute kidney injury network) criteria, UO (urinary output) is a predictor for AKI. OBJECTIVES: The goal of this study was to determine the effects of some AKI risk factors on AKI and also to investigate changes in UO as a predictor of AKI using joint modeling. PATIENTS AND METHODS: In a retrospective study, 300 cardiac-operated patients, who had been admitted over a period of three years, were selected according to the consecutive sample selection method, using the ICU at Masih Daneshvari Hospital in Iran as a referral center. The random mixed effect model and the survival model were used to investigate UO changes and estimate the effect of UO and other risk factors on the hazard rate of AKI in a joint analysis. RESULTS: AKI occurred in 38.0% of patients. A significant decrease of UO occurred more often in female and infected patients, as well as those with a low DBP (diastolic blood pressure). The survival model showed that the risk of AKI in females, older patients and patients with low DBP, lower UO and with infection was higher (P = 0.001). Using joint modeling, the association parameter between the risk of AKI and UO was estimated (-0.3, P = 0.002). CONCLUSIONS: Where there is a relationship between two longitudinal and survival responses, joint modeling can estimate it.

Treatment of lethal acetylsalicylic acid poisoning without hemodialysis.

Case: A woman aged in her 20s ingested approximately 99 g acetylsalicylic acid, and was transported to our hospital 2 h later. She was lucid, but complained of hearing loss and tinnitus. We performed gastric lavage and gave her activated charcoal several times. We attempted to maintain the urinary pH at 7.5 and output above 100 mL/h while preparing for urgent hemodialysis. Outcome: It was revealed after discharge that the blood concentration of acetylsalicylic acid was 103.8 mg/dL on admission (lethal dose level) and had decreased to 35.4 mg/dL by the next morning. The half-life was 8.5 h. Conclusion: Hemodialysis is strongly recommended for patients who take a lethal dose of acetylsalicylic acid. However, by carefully evaluating the vital signs and urinary output and pH, while preparing for emergency hemodialysis, we consider that it is possible to treat acetylsalicylic acid poisoning by alkaline diuresis and critical supportive care.