Diuretic therapy

Optimal Initial Intravenous Loop Diuretic Dosing in Acute Decompensated Heart Failure

Background

Nearly one-half of patients admitted with acute decompensated heart failure (ADHF) are discharged with unresolved congestion, elevating rehospitalization risk. This may be due to suboptimal intravenous (IV) loop diuretic dosing, which may be influenced by home oral diuretic dose.

Objectives

The objective of this study was to determine the association between: 1) home oral loop diuretic dose and optimal initial IV loop diuretic dosing in ADHF; and 2)receiving optimal initial IV loop diuretic dosing and length of stay and 30-day readmission.

Methods

Retrospective analysis of adults admitted to a large U.S. hospital for ADHF on home oral loop diuretics from 1 January 2014 to 21 December 2021. Patients were categorized by home dose: low (≤40 mg furosemide equivalents), medium (>40-80 mg furosemide equivalents), and high (>80 mg furosemide equivalents). Optimal initial IV dosing was considered ≥2 times home oral dosing. Poisson regression models estimated prevalence ratios (CIs) for optimal initial IV loop diuretic dosing.

Results

Among 3,269 adults admitted for ADHF (mean age 63 years, 62% male), optimal initial IV dosing occurred in 2,218 (67.9%). The prevalence of optimal initial IV dosing among low, medium, and high home dosing was 95.5%, 59.9%, and 4.0%, respectively. Adjusted prevalence ratios for optimal IV dosing with high and medium home dosing, compared to low, were 0.05 (95% CI: 0.03-0.07) and 0.66 (95% CI: 0.62-0.70), respectively. There was no difference in length of stay or 30-day readmission between optimal and suboptimal initial IV diuretic dosing.

Conclusions

Among patients with ADHF, higher home loop diuretic dose was strongly associated with a substantially lower likelihood of optimal initial IV diuretic dosing.

Semaglutide and diuretic use in obesity-related heart failure with preserved ejection fraction: a pooled analysis of the STEP-HFpEF and STEP-HFpEF-DM trials

BACKGROUND AND AIMS

In the STEP-HFpEF trial programme, treatment with semaglutide resulted in multiple beneficial effects in patients with obesity-related heart failure with preserved ejection fraction (HFpEF). Efficacy may vary according to baseline diuretic use, and semaglutide treatment could modify diuretic dose.

METHODS

In this pre-specified analysis of pooled data from the STEP-HFpEF and STEP-HFpEF-DM trials (n = 1145), which randomized participants with HFpEF and body mass index ≥ 30 kg/m2 to once weekly semaglutide 2.4 mg or placebo for 52 weeks, we examined whether efficacy and safety endpoints differed by baseline diuretic use, as well as the effect of semaglutide on loop diuretic use and dose changes over the 52-week treatment period.

RESULTS

At baseline, across no diuretic (n = 220), non-loop diuretic only (n = 223), and loop diuretic [<40 (n = 219), 40 (n = 309), and >40 (n = 174) mg/day furosemide equivalents] groups, there was progressively higher prevalence of hypertension and atrial fibrillation; and greater severity of obesity and heart failure. Over 52 weeks of treatment, semaglutide had a consistent beneficial effect on change in body weight across diuretic use categories (adjusted mean difference vs. placebo ranged from -8.8% [95% confidence interval (CI) -10.3, -6.3] to -6.9% [95% CI -9.1, -4.7] from no diuretics to the highest loop diuretic dose category; interaction P = .39). Kansas City Cardiomyopathy Questionnaire clinical summary score improvement was greater in patients on loop diuretics compared to those not on loop diuretics (adjusted mean difference vs. placebo: +9.3 [6.5; 12.1] vs. +4.7 points [1.3, 8.2]; P = .042). Semaglutide had consistent beneficial effects on all secondary efficacy endpoints (including 6 min walk distance) across diuretic subgroups (interaction P = .24-.92). Safety also favoured semaglutide vs. placebo across the diuretic subgroups. From baseline to 52 weeks, loop diuretic dose decreased by 17% in the semaglutide group vs. a 2.4% increase in the placebo group (P < .0001). Semaglutide (vs. placebo) was more likely to result in loop diuretic dose reduction (odds ratio [OR] 2.67 [95% CI 1.70, 4.18]) and less likely dose increase (OR 0.35 [95% CI 0.23, 0.53]; P < .001 for both) from baseline to 52 weeks.

CONCLUSIONS

In patients with obesity-related HFpEF, semaglutide improved heart failure-related symptoms and physical limitations across diuretic use subgroups, with more pronounced benefits among patients receiving loop diuretics at baseline. Reductions in weight and improvements in exercise function with semaglutide vs. placebo were consistent in all diuretic use categories. Semaglutide also led to a reduction in loop diuretic use and dose between baseline and 52 weeks.

CLINICAL TRIAL REGISTRATION

NCT04788511 and NCT04916470.

Fluid accumulation syndrome in sepsis and septic shock: pathophysiology, relevance and treatment-a comprehensive review

In this review, we aimed to comprehensively summarize current literature on pathophysiology, relevance, diagnosis and treatment of fluid accumulation in patients with sepsis/septic shock. Fluid accumulation syndrome (FAS) is defined as fluid accumulation (any degree, expressed as percentage from baseline body weight) with new onset organ-failure. Over the years, many studies have described the negative impact of FAS on clinically relevant outcomes. While the relationship between FAS and ICU outcomes is well described, uncertainty exists regarding its diagnosis, monitoring and treatment. A stepwise approach is suggested to prevent and treat FAS in patients with septic shock, including minimizing fluid intake (e.g., by limiting intravenous fluid administration and employing de-escalation whenever possible), limiting sodium and chloride administration, and maximizing fluid output (e.g., with diuretics, or renal replacement therapy). Current literature implies the need for a multi-tier, multi-modal approach to de-resuscitation, combining a restrictive fluid management regime with a standardized early active de-resuscitation, maintenance fluid reduction (avoiding fluid creep) and potentially using physical measures such as compression stockings.Trial registration: Not applicable.

Potassium levels in women with polycystic ovary syndrome using spironolactone for long-term

OBJECTIVE

Spironolactone (SPL) has been used to manage hyperandrogenic manifestations in women with polycystic ovary syndrome (PCOS), but data on the risk of hyperkalemia in this population are scarce. The aim of this study was to evaluate the incidence of hyperkalemia in women with PCOS using SPL in the long term.

DESIGN

Single-centre retrospective study.

PATIENTS

Inclusion and analysis of 98 treatment periods in 78 women with PCOS (20 of whom were duplicates, returning after treatment interruption for a mean of 38 months) who received SPL for a minimum of 12 months and had at least three measurements of potassium levels over time.

MEASUREMENTS

Clinical and hormonal profiles before and during SPL treatment.

RESULTS

Mean age was 29.1 (SD: 9.6) years, and body mass index was 32.2 (SD: 8.1) kg/m². Nine patients had diabetes, and 22 had prediabetes. SPL was used in combination with combined oral contraceptive pills in 55 participants and progestin-only pills/long-acting reversible contraception in 28; metformin was added in 35, and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers in 15. Median SPL dose was 100 (range: 50-150) mg. A total of 327 serum potassium measurements were obtained (84 pre-exposure and 243 postexposure). Four potassium measurements were above the reference range before exposure and 19 during exposure. All potassium measurements above the reference range during follow-up were classified as mild hyperkalemia (5.1-5.5 mEq/L).

CONCLUSIONS

The present findings suggest that women with PCOS, without kidney or heart disease, using SPL combined with hormonal contraception for managing clinical hyperandrogenism have a low incidence of hyperkalemia and well-tolerated minor adverse effects.

The protective effect of Bergamot Polyphenolic Fraction on reno-cardiac damage induced by DOCA-salt and unilateral renal artery ligation in rats

To date, the complex pathological interactions between renal and cardiovascular systems represent a real global epidemic in both developed and developing countries. In this context, renovascular hypertension (RVH) remains among the most prevalent, but also potentially reversible, risk factor for numerous reno-cardiac diseases in humans and pets. Here, we investigated the anti-inflammatory and reno-cardiac protective effects of a polyphenol-rich fraction of bergamot (BPF) in an experimental model of hypertension induced by unilateral renal artery ligation. Adult male Wistar rats underwent unilateral renal artery ligation and treatment with deoxycorticosterone acetate (DOCA) (20 mg/kg, s.c.), twice a week for a period of 4 weeks, and 1% sodium chloride (NaCl) water (n = 10). A subgroup of hypertensive rats received BPF (100 mg/kg/day for 28 consecutive days, n = 10) by gavage. Another group of animals was treated with a sub-cutaneous injection of vehicle (that served as control, n = 8). Unilateral renal artery ligation followed by treatment with DOCA and 1% NaCl water resulted in a significant increase in mean arterial blood pressure (MAP; p< 0.05. vs CTRL) which strongly increased the resistive index (RI; p<0.05 vs CTRL) of contralateral renal artery flow and kidney volume after 4 weeks (p<0.001 vs CTRL). Renal dysfunction also led to a dysfunction of cardiac tissue strain associated with overt dyssynchrony in cardiac wall motion when compared to CTRL group, as shown by the increased time-to-peak (T2P; p<0.05) and the decreased whole peak capacity (Pk; p<0.01) in displacement and strain rate (p<0.05, respectively) in longitudinal motion. Consequently, the hearts of RAL DOCA-Salt rats showed a larger time delay between the fastest and the lowest region (Maximum Opposite Wall Delay-MOWD) when compared to CTRL group (p<0.05 in displacement and p <0.01 in strain rate). Furthermore, a significant increase in the levels of the circulating pro-inflammatory cytokines and chemokines (p< 0.05 for IL-12(40), p< 0.01 for GM-CSF, KC, IL-13, and TNF- α) and in the NGAL expression of the ligated kidney (p< 0.001) was observed compared to CTRL group. Interestingly, this pathological condition is prevented by BPF treatment. In particular, BPF treatment prevents the increase of blood pressure in RAL DOCA-Salt rats (p< 0.05) and exerts a protective effect on the volume of the contralateral kidney (p <0.01). Moreover, BPF ameliorates cardiac tissue strain dysfunction by increasing Pk in displacement (p <0.01) and reducing the T2P in strain rate motion (p<0.05). These latter effects significantly improve MOWD (p <0.05) preventing the overt dyssynchrony in cardiac wall motion. Finally, the reno-cardiac protective effect of BPF was associated with a significant reduction in serum level of some pro-inflammatory cytokines and chemokines (p<0.05 for KC and IL-12(40), p<0.01 for GM-CSF, IL-13, and TNF- α) restoring physiological levels of renal neutrophil gelatinase-associated lipocalin (NGAL, p<0.05) protein of the tethered kidney. In conclusion, the present results show, for the first time, that BPF promotes an efficient renovascular protection preventing the progression of inflammation and reno-cardiac damage. Overall, these data point to a potential clinical and veterinary role of dietary supplementation with the polyphenol-rich fraction of citrus bergamot in counteracting hypertension-induced reno-cardiac syndrome.

Furosemide in pediatric intensive care: a retrospective cohort analysis

Introduction

Furosemide is the most commonly used medication in pediatric intensive care. Growing data indicates improved hemodynamic stability and efficacy of furosemide infusions compared to intermittent injections, thereby suggesting furosemide infusions might be considered as first line therapy in critically ill, paediatric patients. The objective of this study is to examine furosemide treatment as either continuous infusions or intermittent injections and subsequent patient outcomes.

Methods

This is a retrospective cohort analysis of patients treated in a pediatric intensive care unit (ICU) over a nine year period (July 31st 2006 and July 31, 2015). Eligible patients were admitted to either the general pediatric or cardiac specific ICU for a duration of at least 6 hours and who received intravenous furosemide treatment.

Results

A total of 7,478 patients were identified who received a total of 118,438 furosemide administrations for a total of 113,951 (96%) intermittent doses and 4,487 (4%) infusions running for a total of 1,588,750 hours. A total of 5,996 (80%) patients received exclusively furosemide injections and 1,482 (20%) patients received at least one furosemide infusion. A total of 193 patients died during ICU admission, amounting to 87 (6%) of the 1,482 patients who received an infusion and 106 (2%) of the 5,996 who received intermittent injections. Multivariable regression analysis showed no statistically significant decrease in adjusted mortality for patients who received furosemide injections compared to furosemide infusions (aOR 1.20, CI 0.76-1.89).

Discussion

This retrospective study observed similar mortality for patients who received furosemide infusions compared to furosemide injections. More research on furosemide in the ICU could provide insights on fluid management, drug effectiveness, and pharmacologic stewardship for critically ill children.

Urine sodium concentration after intravenous furosemide in dogs with acute congestive heart failure and correlation with treatment efficacy

BACKGROUND

Poor natriuresis is a potential marker of diuretic resistance in dogs with acute congestive heart failure (CHF) but little is known about the relationship between urine sodium concentration (uNa) and frequency of successful decongestion. Supplemental O2 is a common treatment in dogs with severe CHF. The time from start to discontinuation of supplemental O2 therapy (DCSO2 ) typically reflects the time course and ease of decongestion.

HYPOTHESIS/OBJECTIVES

Urine Na concentration after IV administration of furosemide will be correlated with duration of treatment with supplemental O2 (timeO2 ) and the cumulative frequency of successful DCSO2 during hospitalization.

ANIMALS

Fifty-one dogs with acute CHF.

METHODS

Retrospective observational single center study.

RESULTS

Dogs with low uNa had significantly longer mean timeO2 than dogs with high uNa (uNa <87 mmol/L, 24.2 ± 2.6 hours vs uNa ≥87 mmol/L, 16.6 ± 1.7 hours; P = .02). Low uNa was correlated with lower cumulative frequency of DCSO2 (12 hour, 28%; 24 hour, 42%; 36 hour, 73%) compared to high uNa (12 hour, 28%; 24 hour, 88%; 36 hour, 96%; P = .005). History of PO loop diuretics, low serum chloride concentration (sCl), and high PCV were associated with low uNa. Urine Na concentration outperformed other metrics of diuretic responsiveness including weight loss.

CONCLUSIONS AND CLINICAL IMPORTANCE

Urine Na concentration after IV furosemide predicted timeO2 and cumulative frequency of DCSO2 in dogs with acute CHF, which likely reflects important aspects of diuretic responsiveness. Urine Na can assess diuretic responsiveness and treatment efficacy in dogs with CHF.

Emerging Device Therapies for Cardiorenal Syndrome

While the existence of cardiorenal perturbations has been known for nearly 2 centuries, only in the past 2 decades has significant progress been made in classifying these alterations and characterizing the pathobiology and hemodynamic signature of cardiorenal syndrome (CRS). Empiric intravenous diuretic therapy with fluid and sodium restriction and selective use of vasoactive agents have remained cornerstones of managing acute heart failure with or without acute CRS; however, recent clinical data has exposed the shortcomings of this approach. The traditional view of CRS has long focused on low cardiac output with resultant renal arterial hypoperfusion as the central hemodynamic derangement but this too, has been challenged by new preclinical and clinical observations. Renal venous congestion/hypertension has since been identified as an important hemodynamic contributor to the development of CRS, resulting in diminished renal perfusion pressure, defined as the difference between arterial driving pressure and renal venous pressure. Novel circulatory renal assist devices for the treatment of acute (type I) CRS are in development and may be divided into 2 broad categories: "pushers" which aim to improve renal arterial perfusion (renal preload) and "pullers" which are designed to reduce renal venous congestion (renal afterload). Numerous devices have shown promise in early-stage clinical studies but none have been approved yet for commercial use in the United States. The value of CRS device therapies will ultimately rest on safety as well as the ability of these devices to effect predictable, meaningful, and durable improvements in renal function along with clinical and hemodynamic markers of congestion.

Combining loop and thiazide diuretics for acute heart failure across the estimated glomerular filtration rate spectrum: A post-hoc analysis of the CLOROTIC trial

AIMS

In patients with acute heart failure (AHF), the addition of hydrochlorothiazide (HCTZ) to furosemide improved diuretic response in the CLOROTIC trial. This work aimed to evaluate if these effects differ across the estimated glomerular filtration rate (eGFR) spectrum.

METHODS AND RESULTS

This post-hoc analysis of the CLOROTIC trial analysed 230 patients with AHF and explored the influence of eGFR on primary and secondary endpoints. The median eGFR was 43 ml/min/1.73 m2 (range 14-109) and 23% had eGFR ≥60 ml/min/1.73 m2 (group 1), 24% from 45 to 59 ml/min/1.73 m2 (group 2), and 53% <45 ml/min/1.73 m2 (group 3). Patients treated with HCTZ had greatest weight loss at 72 h in all three groups, but patients in group 1 had a significantly greater response (-2.1 kg [-3.0 to 0.5]), compared to patients in groups 2 (-1.3 kg [-2.3 to 0.2]) and 3 (-0.1 kg [-1.3 to 0.4]) (p-value for interaction = 0.246). At 96 h, the differences in weight were -1.8 kg (-3.0 to -0.3), -1.4 kg (-2.6 to 0.3), and -0.5 kg (-1.3 to -0.1) in groups 1, 2, and 3, respectively (p-value for interaction = 0.256). There were no significant differences observed with the addition of HCTZ in terms of diuretic response, mortality or rehospitalizations, or safety endpoints (impaired renal function, hyponatraemia, and hypokalaemia) among the three eGFR groups (all p-values for interaction were no significant).

CONCLUSION

The addition of eGFR-adjusted doses of oral HCTZ to loop diuretics in patients with AHF improved diuretic response across the eGFR spectrum.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: NCT01647932; EudraCT number: 2013-001852-36.

Protocolised early de-resuscitation in septic shock (REDUCE): protocol for a randomised controlled multicentre feasibility trial

BACKGROUND

Fluid overload is associated with excess mortality in septic shock. Current approaches to reduce fluid overload include restrictive administration of fluid or active removal of accumulated fluid. However, evidence on active fluid removal is scarce. The aim of this study is to assess the efficacy and feasibility of an early de-resuscitation protocol in patients with septic shock.

METHODS

All patients admitted to the intensive care unit (ICU) with a septic shock are screened, and eligible patients will be randomised in a 1:1 ratio to intervention or standard of care.

INTERVENTION

Fluid management will be performed according to the REDUCE protocol, where resuscitation fluid will be restricted to patients showing signs of poor tissue perfusion. After the lactate has peaked, the patient is deemed stable and assessed for active de-resuscitation (signs of fluid overload). The primary objective of this study is the proportion of patients with a negative cumulative fluid balance at day 3 after ICU. Secondary objectives are cumulative fluid balances throughout the ICU stay, number of patients with fluid overload, feasibility and safety outcomes and patient-centred outcomes. The primary outcome will be assessed by a logistic regression model adjusting for the stratification variables (trial site and chronic renal failure) in the intention-to-treat population.

ETHICS AND DISSEMINATION

The study was approved by the respective ethical committees (No 2020-02197). The results of the REDUCE trial will be published in an international peer-reviewed medical journal regardless of the results.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, NCT04931485.

Cardiovascular Consequences of Acute Kidney Injury: Treatment Options

Soon after haemodialysis was introduced into clinical practice, a high risk of cardiac death was noted in end-stage renal disease. However, only in the last decade has it become clear that any renal injury, acute or chronic, is associated with high overall and cardiovascular lethality. The need for early recognition of kidney damage in cardiovascular pathology to assess risk and develop tactics for patient management contributed to the emergence of the concept of the "cardiorenal syndrome" (CRS). CRS is a pathophysiological disorder of the heart and kidneys in which acute or chronic dysfunction of one of these organs leads to acute or chronic dysfunction of the other. The beneficial effect of ultrafiltration as a component of renal replacement therapy (RRT) is due to the elimination of hyperhydration, which ultimately affects the improvement in cardiac contractile function. This review considers the theoretical background, current status of CRS, and future potential of RRT, focusing on the benefits of ultrafiltration as a therapeutic option.

Pharmacological Nephroprotection in Non-Diabetic Chronic Kidney Disease-Clinical Practice Position Statement of the Polish Society of Nephrology

Chronic kidney disease (CKD) is a modern epidemic worldwide. Introducing renin-angiotensin system (RAS) inhibitors (i.e., ACEi or ARB) not only as blood-pressure-lowering agents, but also as nephroprotective drugs with antiproteinuric potential was a milestone in the therapy of CKD. For decades, this treatment remained the only proven strategy to slow down CKD progression. This situation changed some years ago primarily due to the introduction of drugs designed to treat diabetes that turned into nephroprotective strategies not only in diabetic kidney disease, but also in CKD unrelated to diabetes. In addition, several drugs emerged that precisely target the pathogenetic mechanisms of particular kidney diseases. Finally, the role of metabolic acidosis in CKD progression (and not only the sequelae of CKD) came to light. In this review, we aim to comprehensively discuss all relevant therapies that slow down the progression of non-diabetic kidney disease, including the lowering of blood pressure, through the nephroprotective effects of ACEi/ARB and spironolactone independent from BP lowering, as well as the role of sodium-glucose co-transporter type 2 inhibitors, acidosis correction and disease-specific treatment strategies. We also briefly address the therapies that attempt to slow down the progression of CKD, which did not confirm this effect. We are convinced that our in-depth review with practical statements on multiple aspects of treatment offered to non-diabetic CKD fills the existing gap in the available literature. We believe that it may help clinicians who take care of CKD patients in their practice. Finally, we propose the strategy that should be implemented in most non-diabetic CKD patients to prevent disease progression.

Nephrotic Syndrome for the Internist

Nephrotic syndrome (NS) is a key clinical entity for the internist to recognize and understand. A wide range of infectious, metabolic, malignant, and autoimmune processes drive nephrosis, leading to a syndrome defined by proteinuria, edema, and hypoalbuminemia. NS occurs due to increased permeability to proteins at the level of the glomerulus, which allows for passage of albumin and other proteins into the urine. Proteinuria leads to a cascade of clinical complications characterized by fluid accumulation, kidney inflammation, and dysregulation of coagulation and immunity. In this article, the authors review the clinically important etiologies of NS that should inform an initial clinical evaluation.

Therapeutic roles of thiazides and loop diuretics in blood pressure control and renal protection against chronic kidney disease

Fluid overload secondary to loss of functional nephron mass can elevate blood pressure, which is characteristic of hypertension shown in chronic kidney disease (CKD). Therefore, it is logical to use diuretics at appropriate dose to lower blood pressure in patients with CKD and hypertension. Despite the theoretical background on the use of diuretics in CKD, there have been no definitive data on the effectiveness or safety of diuretics as first-line therapy for the management of hypertension in patients with CKD. Results from some clinical trials have demonstrated that diuretics would not lower blood pressure. They could even worsen electrolyte imbalance and kidney function when they are administered in patients with CKD. Major clinical practice guidelines on management of blood pressure or CKD have stated that evidence for benefits of thiazide diuretics is not conclusive yet in patients with advanced CKD, although loop diuretics are often effective for volume control at lower glomerular filtration rate. Recently, evidence for diuretics as effective blood pressure lowering agents in patients with advanced CKD is increasing. Renoprotective effect of thiazide or loop diuretics might represent a consequence of their influence on blood pressure or their ability to potentiate the effect of renin-angiotensin system blockade by making intraglomerular pressure more renin-angiotensin system-dependent, although their direct benefit on renal function remains controversial. This review summarizes recent data on the possible role of diuretics in lowering blood pressure, slowing the progression of kidney disease, and reducing cardiovascular risk in CKD patients.

Predictors of Poor Very Early Diuretic Response and Effectiveness of Early Tolvaptan in Symptomatic Acute Heart Failure

BACKGROUND

Diuretic response (DR) in patients with symptomatic acute decompensated heart failure (ADHF) has an impact on prognosis. This study aimed to identify predictive factors influencing acute 6 h poor DR and to assess DR after early administration of tolvaptan (TLV).

METHODS

This multicenter retrospective study included 1670 patients who were admitted for ADHF and received intravenous furosemide within 1 h of presentation in clinical scenario 1 or 2 defined based on initial systolic blood pressure ≥100 mmHg with severe symptoms (New York Heart Association class III or IV (n = 830). The score for the poor DR factors in the very acute phase was calculated in patients treated with furosemide-only diuretics (n = 439). The DR to TLV administration was also assessed in patients who received an additional dose of TLV within 6 h (n = 391).

RESULTS

The time since discharge from the hospital for a previous heart failure < 3 months (odds ratio [OR] 2.78, 95% confidence interval [CI] 1.34-5.83; p = 0.006), loop diuretics at admission (OR 3.05, 95% CI 1.74-5.36; p < 0.0001), and estimated glomerular filtration rate (eGFR) < 45 mL/min/1.73 m² (OR 2.99, 95% CI 1.58-5.74; p = 0.0007) were independent determinants of poor DR. The frequency of poor DR according to the risk stratification group was low risk (no risk factor), 18.9%; middle risk (one risk factor), 33.1%; and high risk (two to three risk factors), 58.0% (p < 0.0001). All risk groups demonstrated a significantly lower incidence of poor DR with early TLV administration: 10.7% in the early TLV group versus 18.9% in the loop diuretics group (p = 0.09) of the low-risk group; 18.4% versus 33.1% (p = 0.01) in the middle-risk group, and 20.2% versus 58.0% (p < 0.0001) in the high-risk group.

CONCLUSION

Early administration of TLV in patients with predicted poor DR contributed to a significant diuretic effect and suppression of worsening renal function.

Combining loop with thiazide diuretics for decompensated heart failure: the CLOROTIC trial

AIMS

To evaluate whether the addition of hydrochlorothiazide (HCTZ) to intravenous furosemide is a safe and effective strategy for improving diuretic response in acute heart failure (AHF).

METHODS AND RESULTS

A prospective, double-blind, placebo-controlled trial, including patients with AHF randomized to receive HCTZ or placebo in addition to an intravenous furosemide regimen. The coprimary endpoints were changes in body weight and patient-reported dyspnoea 72 h after randomization. Secondary outcomes included metrics of diuretic response and mortality/rehospitalizations at 30 and 90 days. Safety outcomes (changes in renal function and/or electrolytes) were also assessed. Two hundred and thirty patients (48 women, 83 years) were randomized. Patients assigned to HCTZ were more likely to lose weight at 72 h than those assigned to placebo [2.3 vs. 1.5 kg; adjusted estimated difference (notionally 95 confidence interval) 1.14 (1.84 to 0.42); P 0.002], but there were no significant differences in patient-reported dyspnoea (area under the curve for visual analogue scale: 960 vs. 720; P 0.497). These results were similar 96 h after randomization. Patients allocated to HCTZ showed greater 24 h diuresis (1775 vs. 1400 mL; P 0.05) and weight loss for each 40 mg of furosemide (at 72 and at 96 h) (P 0.001). Patients assigned to HCTZ more frequently presented impaired renal function (increase in creatinine 26.5 moL/L or decrease in eGFR 50; 46.5 vs. 17.2; P 0.001), but hypokalaemia and hypokalaemia were similar between groups. There were no differences in mortality or rehospitalizations.

CONCLUSION

The addition of HCTZ to loop diuretic therapy improved diuretic response in patients with AHF.

Cardiorenal Interactions: A Review

A complex interaction occurs between cardiac and renal function. They are intricately tied together, and a range of disorders in both the heart and kidneys can alter the function of the other. The pathophysiology is complex, and these conditions are termed cardiorenal syndromes. They can be acute and/or chronic in nature, they result in and from hemodynamic consequences, systemic congestion, and metabolic abnormalities, and they lead to dysfunction of both the heart and kidneys. The aim of this article is to provide a review for cardiologists and intensivists who are treating patients for whom cardiac and renal interactions may complicate their picture. We review acute kidney injuries, management of the complications of renal dysfunction, renal replacement therapy, and cardiorenal syndromes.

Diuretic Renal Scintigraphy Protocol Considerations

Diuretic renal scintigraphy plays a critical diagnostic role by providing a physiologic means for differentiating between obstructive and nonobstructive hydronephrosis as well as assessing the function of the affected kidney. The exam accuracy is highly dependent upon and benefits from close attention to the protocol. This article reviews kidney anatomy and physiology, patient preparation, available radiopharmaceuticals, diuretic administration, acquisition, processing, quantification, and interpretation criteria.

Preclinical Pharmacokinetic Studies of a Novel Diuretic Inhibiting Urea Transporters

Urea transporter (UT) inhibitors are a class of promising novel diuretics that do not cause the imbalance of Na+, K+, Cl-, and other electrolytes. In our previous studies, 25a, a promising diuretic candidate inhibiting UT, was discovered and showed potent diuretic activities in rodents. Here, a sensitive liquid chromatography-tandem mass spectrometry method for the quantitation of 25a in rat plasma, urine, feces, bile, and tissue homogenates was developed and validated to support the preclinical pharmacokinetic studies. The tissue distribution, excretion, and plasma protein binding were investigated in rats. After a single oral dose of 25a at 25, 50, and 100 mg/kg, the drug exposure increased linearly with the dose. The drug accumulation was observed after multiple oral doses compared to a single dose. In the distribution study, 25a exhibited a wide distribution to tissues with high blood perfusion, such as kidney, heart, lung, and spleen, and the lowest distribution in the brain and testis. The accumulative excretion rate of 25a was 0.14%, 3.16%, and 0.018% in urine, feces, and bile, respectively. The plasma protein binding of 25a was approximately 60% in rats and 40% in humans. This is the first study on the preclinical pharmacokinetic profiles of 25a.

Associations of sodium and potassium intake with chronic kidney disease in a prospective cohort study: findings from the Hispanic Community Health Study/Study of Latinos, 2008-2017

BACKGROUND

According to dietary recommendations, reduction of sodium intake has potential to reduce Chronic Kidney Disease (CKD) risk; however the role of dietary potassium and the sodium -to- potassium ratio in the development of CKD is unclear.

METHODS

We studied 9778 participants of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) from four US urban communities. Participants were aged 18-74 yrs., free from CKD at baseline in 2008-2011 and re-examined between 2014 and - 2017. Dietary intake of sodium, potassium and the ratio of dietary sodium -to- potassium were measured from two baseline 24-h dietary recalls. Incident CKD was defined as: 1) estimated glomerular filtration rate (eGFR) decline of 1 unit per year and eGFR < 60 ml/min/1.73m2 or 2) albumin to creatinine ratio ≥ 30 mg/g at the follow-up visit. We used multivariable survey weighted Poisson regression to estimate adjusted incident rates of incident CKD.

RESULTS

At baseline, mean age was 41 years. Average follow up time was 6.2 years. From fully adjusted Poisson regression analyses, self-reported sodium intake was not associated with incident CKD. However, for each 500 mg decrement in potassium intake, there was an 11% increase risk of incident CKD (IRR = 1.11, 95% CI = 1.00, 1.24). Additionally, every 1 M ratio increment of sodium -to -potassium ratio was associated with a 21% increased risk of incident CKD (IRR = 1.21, 95% CI = 1.02, 1.45), p < 0.05).

CONCLUSIONS

We conclude that diets low in potassium and high in sodium are associated with increased risk of developing chronic kidney disease among healthy US Hispanic/Latino adults.

Diuretic therapy in congestive heart failure

In heart failure, fluid overload is a major pathological mechanism leading to vascular congestion, pulmonary congestion and elevated jugular venous pressures. Diuretics play a significant role in the management of patients with congestive heart failure. It is used to relieve the congestive symptoms of heart failure. However, the appropriate use of diuretics remains challenging due to various complications like electrolyte abnormalities, worsening renal function and diuretic resistance. This has prompted towards the search of safer and effective alternatives. This review evaluates the use of diuretics in congestive heart failure and discusses the complications of different types of diuretics, which is essential for successful management of congestion in patients with heart failure and hence to optimise the outcome for the patients.

Classic and Novel Mechanisms of Diuretic Resistance in Cardiorenal Syndrome

Despite the incompletely understood multiple etiologies and underlying mechanisms, cardiorenal syndrome is characterized by decreased glomerular filtration and sodium avidity. The underlying level of renal sodium avidity is of primary importance in driving a congested heart failure phenotype and ultimately determining the response to diuretic therapy. Historically, mechanisms of kidney sodium avidity and resultant diuretic resistance were primarily extrapolated to cardiorenal syndrome from non-heart failure populations. Yet, the mechanisms appear to differ between these populations. Recent literature in acute decompensated heart failure has refuted several classically accepted diuretic resistance mechanisms and reshaped how we conceptualize diuretic resistance mechanisms in cardiorenal syndrome. Herein, we propose an anatomically based categorization of diuretic resistance mechanisms to establish the relative importance of specific transporters and translate findings toward therapeutic strategies. Within this categorical structure, we discuss classic and novel mechanisms of diuretic resistance.

Fluid Homeostasis and Diuretic Therapy in the Neonate

Understanding physiologic water balance and homeostasis mechanisms in the neonate is critical for clinicians in the NICU as pathologic fluid accumulation increases the risk for morbidity and mortality. In addition, once this process occurs, treatment is limited. In this review, we will cover fluid homeostasis in the neonate, explain the implications of prematurity on this process, discuss the complexity of fluid accumulation and the development of fluid overload, identify mitigation strategies, and review treatment options.

Inpatient Diuretic Management of Acute Heart Failure: A Practical Review

The inpatient treatment of acute heart failure (AHF) is aimed at achieving euvolemia, relieving symptoms, and reducing rehospitalization. Adequate treatment of AHF is rooted in understanding the pharmacokinetics and pharmacodynamics of select diuretic agents used to achieve decongestion. While loop diuretics remain the primary treatment of AHF, the dosing strategies of loop diuretics and the use of adjunct diuretic classes to augment clinical response can be complex. This review examines the latest strategies for diuretic management in patients with AHF, including dosing and monitoring strategies, interaction of diuretics with other medication classes, use adjunctive therapies, and assessing endpoints for diuretic. The goal of the review is to guide the reader through commonly encountered clinical scenarios and pitfalls in the diuretic management of patients with AHF.

Efficacy and Renal Tolerability of Ultrafiltration in Acute Decompensated Heart Failure: A Meta-analysis and Systematic Review of 19 Randomized Controlled Trials

Background: Acute decompensated heart failure (ADHF) is a life-threatening and costly disease. Controversy remains regarding the efficacy and renal tolerability of ultrafiltration for treating ADHF. We therefore performed this meta-analysis to evaluate this clinical issue.Methods: A search of PubMed, EMBASE, and the Cochrane database of controlled trials was performed from inception to March 2021 for relevant randomized controlled trials. The quality of the included trials and outcomes was evaluated with the use of the risk of bias assessment tool and the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach, respectively. The risk ratio and the standardized mean difference (SMD) or weighted mean difference (WMD) were computed and pooled with fixed-effects or random-effects models.Results: This meta-analysis included 19 studies involving 1281 patients. Ultrafiltration was superior to the control treatments for weight loss (WMD 1.24 kg, 95% confidence interval [CI] 0.38‐2.09 kg, P=0.004) and fluid removal (WMD 1.55 L, 95% CI 0.51‐2.59 l, P=0.003) and was associated with a significant increase in serum creatinine level compared with the control treatments (SMD 0.15 mg/dL, 95% CI 0.00‐0.30 mg/dL, P=0.04). However, no significant effects were found for serum N-terminal prohormone of brain natriuretic peptide level, length of hospital stay, all-cause mortality, or all-cause rehospitalization in the ultrafiltration group.Conclusions: The use of ultrafiltration in patients with ADHF is superior to the use of the control treatments for weight loss and fluid removal, but has adverse renal effects and lacks significant effects on long-term prognosis, indicating that this approach to decongestion in ADHF patients is efficient for fluid management but less safe renally.

Comparison of Clinical Outcomes and Safety Associated With Chlorthalidone vs Hydrochlorothiazide in Older Adults With Varying Levels of Kidney Function

IMPORTANCE

Thiazide diuretics are commonly prescribed for the treatment of hypertension, a disease highly prevalent among older individuals and in those with chronic kidney disease. How specific thiazide diuretics compare in regard to safety and clinical outcomes in these populations remains unknown.

OBJECTIVE

To compare safety and clinical outcomes associated with chlorthalidone or hydrochlorothiazide use among older adults with varying levels of kidney function.

DESIGN, SETTING, AND PARTICIPANTS

This population-based retrospective cohort study was conducted in Ontario, Canada, from 2007 to 2015. Participants included adults aged 66 years or older who initiated chlorthalidone or hydrochlorothiazide during this period. Data were analyzed from December 2019 through September 2020.

EXPOSURES

New chlorthalidone users were matched 1:4 with new hydrochlorothiazide users by a high-dimensional propensity score. Time-to-event models accounting for competing risks examined the associations between chlorthalidone vs hydrochlorothiazide use and the outcomes of interest overall and within estimated glomerular filtration rate (eGFR) categories (≥60, 45-59, and <45 mL/min/1.73 m2).

MAIN OUTCOMES AND MEASURES

The outcomes of interest were adverse kidney events (ie, eGFR decline ≥30%, dialysis, or kidney transplantation), cardiovascular events (composite of myocardial infarction, coronary revascularization, heart failure, or atrial fibrillation), all-cause mortality, and electrolyte anomalies (ie, sodium or potassium levels outside reference ranges).

RESULTS

After propensity score matching, the study cohort included 12 722 adults (mean [SD] age, 74 [7] years; 7063 [56%] women; 5659 [44%] men; mean [SD] eGFR, 69 [19] mL/min/1.73 m2), including 2936 who received chlorthalidone and 9786 who received hydrochlorothiazide. Chlorthalidone use was associated with a higher risk of eGFR decline of 30% or greater (hazard ratio [HR], 1.24 [95% CI, 1.13-1.36]) and cardiovascular events (HR, 1.12 [95% CI, 1.04-1.22]) across all eGFR categories compared with hydrochlorothiazide use. Chlorthalidone use was also associated with a higher risk of hypokalemia compared with hydrochlorothiazide use, which was more pronounced among those with higher eGFR (eGFR ≥60 mL/min/1.73 m2: HR, 1.86 [95% CI, 1.67-2.08]; eGFR 45-59 mL/min/1.73 m2: HR, 1.57 [95% CI, 1.25-1.96]; eGFR <45 mL/min/1.73 m2: HR, 1.10 [95% CI, 0.84-1.45]; P for interaction = .001). No significant differences were observed between chlorthalidone and hydrochlorothiazide for dialysis or kidney transplantation (HR, 1.44 [95% CI, 0.88-2.36]), all-cause mortality (HR, 1.10 [95% CI, 0.93-1.29]), hyperkalemia (HR, 1.05 [95% CI, 0.79-1.39]), or hyponatremia (HR, 1.14 [95% CI, CI 0.98-1.32]).

CONCLUSIONS AND RELEVANCE

This cohort study found that among older adults, chlorthalidone use was associated with a higher risk of eGFR decline, cardiovascular events, and hypokalemia compared with hydrochlorothiazide use. The excess risk of hypokalemia with chlorthalidone was attenuated in participants with reduced kidney function. Placed in context with prior observational studies comparing the safety and clinical outcomes associated with thiazide diuretics, these results suggest that there is no evidence to prefer chlorthalidone over hydrochlorothiazide.

Efficacy and safety of oral tolvaptan in patients undergoing hemodialysis: a Phase 2, double-blind, randomized, placebo-controlled trial

BACKGROUND

Loop diuretics are used to manage fluid retention in patients with end-stage kidney disease undergoing hemodialysis (HD). This randomized, double-blind, placebo-controlled, Phase 2 trial evaluated the efficacy and safety of tolvaptan, a vasopressin V2 receptor antagonist, in Japanese HD patients.

METHODS

A total of 124 patients (24-h urine volume ≥500 mL) on thrice-weekly HD were randomized to receive oral tolvaptan 15 mg/day (n = 40), tolvaptan 30 mg/day (n = 40) or placebo (n = 44) for 24 weeks. Efficacy endpoints were change from baseline in 24-h urine volume, total fluid removal by HD per week and interdialytic weight gain (IDWG). Safety was assessed via the incidence of treatment-emergent adverse events (TEAEs).

RESULTS

At treatment end, the difference (95% confidence interval) from the placebo group in the mean change from baseline in 24-h urine volume was significant in the tolvaptan 15 mg {429.1 mL [95% confidence interval (CI) 231.0, 627.2]; P < 0.0001} and 30 mg [371.6 mL (95% CI 144.1, 599.2); P = 0.0017] groups. The mean changes from baseline in total fluid removal by HD and IDWG were not significantly different in the tolvaptan groups versus the placebo group. Although the proportion of patients with TEAEs was lower in the placebo group (77.3%) than in the tolvaptan groups (92.3%), tolvaptan was safe and well-tolerated during the study period.

CONCLUSIONS

Tolvaptan significantly sustained diuretic action for 24 weeks in HD patients but did not reduce total fluid removal by HD per week and IDWG to the same extent.

Loop Diuretics in Infants with Heart Failure

Tremendous advances have been made in the last 5 decades in the surgical management of congenital heart disease (CHD). Most infants affected by clinically significant CHD are at risk for developing heart failure (HF). Adult HF management is mostly evidence-based and our knowledge in this field has expanded significantly in the past decade. However, data on management approaches for HF in infants are limited. The indications and implications for various medications and interventions in patients with HF secondary to CHD are an upcoming area of interest. It is critical that we expand our ability to prevent, detect, and manage HF in the pediatric population.

Head to head comparison of [99mTc]Tc(CO)3(NTA) and [99mTc]Tc-MAG3 in patients with suspected obstruction

PURPOSE

^99mTc-tricarbonyl-nitrilotriacetic acid, [^99mTc]Tc(CO)₃(NTA), is a new ^99mTc-renal radiopharmaceutical with a clearance equal to that of ¹³¹I-ortho-iodohippuran, [¹³¹I]I-OIH. Our purpose was to compare the performance of [^99mTc]Tc(CO)₃(NTA) and [^99mTc]Tc-MAG3 in patients with suspected obstruction.

METHODS

[^99mTc]Tc(CO)₃(NTA) was prepared with commercially available NTA ligand and CRS Isolink kit, and isolated by HPLC. Eighteen adult patients referred for diuretic renography received an intravenous injection of approximately 40 mg of furosemide 15 min prior to either [^99mTc]Tc(CO)₃(NTA) or [^99mTc]Tc-MAG3 (mean activity of 47 ± 4.4 MBq). Data were acquired for 24 min followed by an anterior image of the liver and gall bladder and a measure of voided volume. Patients received a second furosemide injection equal to one third of the original dose followed fifteen minutes later by administration of the alternate tracer, mean activity of 320 ± 34 MBq. Clearances were measured using a camera-based technique.

RESULTS

The clearance of NTA was greater than that of MAG3, 331 ± 146 versus 271 ± 105 mL/min/1.73 m², respectively, p < 0.0001. The kidney to background ratio for NTA was greater than that of MAG3 for both left and right kidneys, p < 0.001; the 20 min/maximum count ratio was significantly less, p < 0.0001. There was no significant difference in the voiding volumes following NTA and MAG3 administration, 598 ± 237 mL versus 498 ± 170 mL, respectively, p = 0.07. Gall bladder activity was not observed with NTA but was present in 6/17 MAG3 studies. Images and renogram curves were comparable except for two patients where the NTA study excluded obstruction but the MAG3 study suggested an indeterminate or obstructed kidney.

CONCLUSIONS

Unlike MAG3, NTA is not eliminated via the hepatobiliary track. Moreover, NTA has a higher kidney to background ratio and more rapid clearance than MAG3. These advantages should allow more robust camera-based clearance measurements and may lead to better discrimination between obstructed and non-obstructed kidneys.

[Volume Management in Chronic kidney disease]

Understanding the (patho-)physiology of volume regulation and osmoregulation is fundamental to guide patient advice and therapy in chronic kidney disease (CKD). Volume regulation primarily impacts the amount of sodium in the body, and it mainly affects the extracellular space, while osmoregulation primarily impacts the amount of free water, and it affects both the intra- and extracellular space. The kidneys control water and sodium homeostasis both through their sensor (e. g. tubuloglomerular feedback) and regulator systems (e. g. sodium reabsorption). Many CKD patients are advised by non-nephrologists to a high fluid intake, although they often do not require a daily intake of more than 1.5 litres. Many CKD patients are hypervolemic, and sodium restriction is of key importance in patients' effort to utilize lifestyle changes as therapeutic means. Pharmacologically, (particularly loop) diuretics are the basis of therapy, increasing sodium excretion. Recent developments shift the focus towards classes of drugs ameliorating prognosis in CKD: sodium-glucose linked transporter 2 (SGLT2) inhibitors have proven beneficial in heart and renal failure - by sodium and fluid excretion, among others; additionally, a novel mineralocorticoid receptor antagonist (MRA), finerenone, was recently shown to improve prognosis in CKD.

Imaging the transmembrane and transendothelial sodium gradients in gliomas

Under normal conditions, high sodium (Na⁺) in extracellular (Na⁺_e) and blood (Na⁺_b) compartments and low Na⁺ in intracellular milieu (Na⁺_i) produce strong transmembrane (ΔNa⁺_mem) and weak transendothelial (ΔNa⁺_end) gradients respectively, and these manifest the cell membrane potential (V_m) as well as blood–brain barrier (BBB) integrity. We developed a sodium (²³Na) magnetic resonance spectroscopic imaging (MRSI) method using an intravenously-administered paramagnetic polyanionic agent to measure ΔNa⁺_mem and ΔNa⁺_end. In vitro ²³Na-MRSI established that the ²³Na signal is intensely shifted by the agent compared to other biological factors (e.g., pH and temperature). In vivo ²³Na-MRSI showed Na⁺_i remained unshifted and Na⁺_b was more shifted than Na⁺_e, and these together revealed weakened ΔNa⁺_mem and enhanced ΔNa⁺_end in rat gliomas (vs. normal tissue). Compared to normal tissue, RG2 and U87 tumors maintained weakened ΔNa⁺_mem (i.e., depolarized V_m) implying an aggressive state for proliferation, whereas RG2 tumors displayed elevated ∆Na⁺_end suggesting altered BBB integrity. We anticipate that ²³Na-MRSI will allow biomedical explorations of perturbed Na⁺ homeostasis in vivo.

Chronic renal dysfunction in cirrhosis: A new frontier in hepatology

Chronic kidney disease (CKD) in patients with liver cirrhosis has become a new frontier in hepatology. In recent years, a sharp increase in the diagnosis of CKD has been observed among patients with cirrhosis. The rising prevalence of risk factors, such as diabetes, hypertension and nonalcoholic fatty liver disease, appears to have contributed significantly to the high prevalence of CKD. Moreover, the diagnosis of CKD in cirrhosis is now based on a reduction in the estimated glomerular filtration rate of < 60 mL/min over more than 3 mo. This definition has resulted in a better differentiation of CKD from acute kidney injury (AKI), leading to its greater recognition. It has also been noted that a significant proportion of AKI transforms into CKD in patients with decompensated cirrhosis. CKD in cirrhosis can be structural CKD due to kidney injury or functional CKD secondary to circulatory and neurohormonal imbalances. The available literature on combined cirrhosis-CKD is extremely limited, as most attempts to assess renal dysfunction in cirrhosis have so far concentrated on AKI. Due to problems related to glomerular filtration rate estimation in cirrhosis, the absence of reliable biomarkers of CKD and technical difficulties in performing renal biopsy in advanced cirrhosis, CKD in cirrhosis can present many challenges for clinicians. With combined hepatorenal dysfunctions, fluid mobilization becomes problematic, and there may be difficulties with drug tolerance, hemodialysis and decision-making regarding the need for liver vs simultaneous liver and kidney transplantation. This paper offers a thorough overview of the increasingly known CKD in patients with cirrhosis, with clinical consequences and difficulties occurring in the diagnosis and treatment of such patients.

Continuous versus intermittent use of furosemide in patients with heart failure and moderate chronic renal dysfunction

Aims

There is paucity of clinical data comparing continuous infusion (CI) with bolus injection (BI) of intravenous loop diuretics in patients with acute decompensated heart failure (ADHF) and chronic renal dysfunction. This study aimed to compare the efficacy and safety of CI versus BI intravenous furosemide administration in patients with ADHF and moderate chronic renal insufficiency.

Methods and results

Acute decompensated heart failure and moderate chronic renal insufficiency [with estimated glomerular filtration rate (eGFR) 15.0–44.9 mL/min/1.73 m²] were randomized to start intravenous furosemide by BI or by a 6 h CI. End points included freedom from congestion at 72 h, the degree of dyspnoea assessed using the 0–10 Borg's category ratio scale, net daily urine output, weight loss during the study, length of hospital stay, total urinary sodium excretion, and development of acute kidney injury or electrolyte disturbance. After 72 h of treatment, the rate of the primary endpoint of freedom from congestion in the CI group was significantly higher than that in the BI group (69.05% vs. 43.59%, P = 0.02). The modified Borg scale indicated patients in the CI group had lower dyspnoea score than those in the BI group at 48 h (4.29 ± 1.23 vs. 5.97 ± 1.56; P = 0.02) and 72 h (1.15 ± 0.35 vs. 2.66 ± 0.83; P = 0.003). There were other significant differences favouring the CI group with regard to net urine output at 72 h (5145.98 ± 621.37 mL vs. 3755.95 ± 456.93 mL; P = 0.007), the mean body weight loss (4.72 ± 1.01 kg vs. 3.53 ± 0.73 kg; P = 0.02) and the total urinary sodium excretion (385.05 ± 38.15 vs. 320.33 ± 37.67; P = 0.02). The length of hospitalization in the CI group was significantly shorter than that in the BI group (10.36 ± 4.20 days vs. 15.68 ± 6.15 days; P = 0.02). No significant differences were observed between groups in the frequency of acute kidney injury, tinnitus, electrolyte disturbance or mortality.

Conclusions

Continuous intravenous infusion of furosemide resulted in significantly greater diuresis than bolus administration of an equal dose in patients with moderate chronic renal insufficiency and ADHF, while no differences emerged in terms of side effects or mortality.

Diuretic-induced hypokalaemia: an updated review

Diuretic-induced hypokalaemia is a common and potentially life-threatening adverse drug reaction in clinical practice. Previous studies revealed a prevalence of 7%-56% of hypokalaemia in patients taking thiazide diuretics. The clinical manifestations of hypokalaemia due to diuretics are non-specific, varying from asymptomatic to fatal arrhythmia. Diagnosis of hypokalaemia is based on the level of serum potassium. ECG is useful in identifying the more severe consequences. A high dosage of diuretics and concomitant use of other drugs that increase the risk of potassium depletion or cardiac arrhythmias can increase the risk of cardiovascular events and mortality. Thiazide-induced potassium depletion may cause dysglycaemia. The risk of thiazide-induced hypokalaemia is higher in women and in black people. Reducing diuretic dose and potassium supplementation are the most direct and effective therapies for hypokalaemia. Combining with a potassium-sparing diuretic or blocker of the renin-angiotensin system also reduces the risk of hypokalaemia. Lowering salt intake and increasing intake of vegetables and fruits help to reduce blood pressure as well as prevent hypokalaemia.

The furosemide stress test, electrolyte response and Renal Index in critically ill patients

BACKGROUND

Acute kidney injury (AKI) is a common syndrome in critically ill patients. The diagnostic ability of traditional markers such as serum creatinine has recently been questioned, and the use of newer tests such as the furosemide stress test or the ultrasound assessment of renal resistive index have been proposed. Aim of the present study was to compare the response to a furosemide stress test, the Renal Index in mechanically ventilated patients with and without acute kidney injury at admission, and who did or did not develop AKI at day three, among those with normal renal function at the CIU admission.

METHODS

Prospective observational study in consecutive mechanically ventilated patients admitted in a general intensive care. Furosemide stress test and ultrasonographical Renal Index were performed at the admission and clinical and laboratory data were collected before and two hours after the furosemide stress text. The urine output after the first and the second hours was recorded.

RESULTS

Forty patients were enrolled, 19 of whom had AKI at admission. The Renal Index was significantly higher in patients with AKI (0.77±0.07 vs. 0.72±0.08, P=0.027); patients with AKI had a significantly lower urine output after the furosemide stress test (400 [340; 1400] vs.1525 [400; 2550] mL; P=0.013). The plasma concentrations of sodium, potassium and chloride were not different before and after the furosemide stress test in patients with and without AKI, whereas in patients with AKI, the total urine output of sodium, potassium and chloride were significantly lower compared to patients without AKI. Similar results were found in patients without AKI at admission and who developed AKI at day three as compared to those who did not develop AKI.

CONCLUSIONS

The response to the furosemide stress test and the Renal Index could be used as additional tools to evaluate the kidney function in critically ill patients.

Trajectory of extracellular fluid volume over time and subsequent risks of end-stage kidney disease and mortality in chronic kidney disease: a prospective cohort study

BACKGROUND

Extracellular fluid volume (ECF) is independently associated with chronic kidney disease (CKD) progression and mortality in patients with CKD, but the prognostic value of the trajectory of ECF over time beyond that of baseline value is unknown.

OBJECTIVES

To characterize ECF trajectory and evaluate its association with the risks of end-stage kidney disease (ESKD) and mortality.

METHODS

From the prospective tricentric NephroTest cohort, we included 1588 patients with baseline measured glomerular filtration rate (mGFR) ≥15 mL min^-1 /1.73 m² and ECF measurement. ECF and GFR were measured repeatedly using the distribution volume and clearance of ⁵¹ Cr-EDTA, respectively. ESKD and mortality were traced through record linkage with the national registries. Adjusted shared random-effect joint models were used to analyse the association between the trajectory of ECF over time and the two competing outcomes.

RESULTS

Patients were mean age 58.7 years, 66.7% men, mean mGFR of 43.6 ± 18.6 mL min^-1 /1.73 m² and mean ECF of 16.1 ± 3.6 L. Over a median follow-up of 5.3 [IQR: 3.0;7.4] years, ECF increased by 136 [95%CI 106;167] mL per year on average, whilst diuretic prescription and 24-hour urinary sodium excretion remained stable. ESKD occurred in 324 (20.4%) patients, and 185 (11.6%) patients died before ESKD. A higher current value of ECF was associated with increased hazards of ESKD (adjusted hazard ratio [aHR]: 1.12 [95%CI 1.06;1.18]; P < 0.001 per 1 L increase in ECF), and death before ESKD (aHR: 1.10 [95%CI 1.04;1.17]; P = 0.002).

CONCLUSIONS

The current value of ECF was associated with the risks of ESKD and mortality, independent of multiple potential confounders, including kidney function decline. This highlights the need for a close monitoring and adjustment of treatment to avoid fluid overload in CKD patients.

[The use of diuretics in chronic heart failure. Position paper of the Russian Heart Failure Society]

The document focuses on key issues of diuretic therapy in CHF from the standpoint of current views on the pathogenesis of edema syndrome, its diagnosis, and characteristics of using diuretics in various clinical situations.

Angiotensin Receptor Neprilysin Inhibitors in HFrEF: Is This the First Disease Modifying Therapy Drug Class Leading to a Substantial Reduction in Diuretic Need?

Despite significant advances in disease modifying therapy in heart failure (HF), diuretics have remained the cornerstone of volume management in all HF phenotypes. Diuretics, alongside their definite acute haemodynamic and symptomatic benefits, also possess many possible deleterious side effects. Moreover, questions remain regarding the prognostic impact of chronic diuretic use. To date, few data exist pertaining to diuretic reduction as a result of individual traditional guideline directed medical therapy in HF with reduced ejection fraction (HFrEF). However, diuretic reduction has been demonstrated with sacubitril/valsartan (angiotensin receptor-neprilysin inhibitor [ARNi]) from the PARADIGM study, as well as, post-marketing reports from our own group and others. Whether the ARNi compound represents the dawn of a new era, where effective therapies will have a more noticeable reduction on diuretic need, remains to be seen. The emergence of sodium glucose transport 2 inhibitors and guanylate cyclase stimulators may further exemplify this issue and potentially extend this benefit to HF patients outside of the HFrEF phenotype. In conclusion, emerging new therapies in HFrEF could reduce the reliance on diuretics in the management of this phenotype of HF. These developments further highlight the clinical importance to continually assess an individual's diuretic requirements through careful volume assessment.

Stent Placement for Malignant Inferior Vena Cava Syndrome in a Patient with Recurrent Colon Cancer

A 70-year-old man was admitted to our hospital with gait disturbance due to marked edema of the lower limbs for more than 6 months. He had been receiving systemic chemotherapy over two years for multiple recurrence after sigmoid colon cancer resection. Contrast-enhanced computed tomography demonstrated severe inferior vena cava (IVC) stenosis due to compression by lymph node metastases, i.e. IVC syndrome. As increased doses of diuretic agents failed to improve the edema, IVC stent placement was performed. This led to significant improvement of the edema and complete gait normalization. This case demonstrates the efficacy of IVC stent placement for IVC syndrome.

Salt-sensitive hypertension in chronic kidney disease: distal tubular mechanisms

Chronic kidney disease (CKD) causes salt-sensitive hypertension that is often resistant to treatment and contributes to the progression of kidney injury and cardiovascular disease. A better understanding of the mechanisms contributing to salt-sensitive hypertension in CKD is essential to improve these outcomes. This review critically explores these mechanisms by focusing on how CKD affects distal nephron Na+ reabsorption. CKD causes glomerulotubular imbalance with reduced proximal Na+ reabsorption and increased distal Na+ delivery and reabsorption. Aldosterone secretion further contributes to distal Na+ reabsorption in CKD and is not only mediated by renin and K+ but also by metabolic acidosis, endothelin-1, and vasopressin. CKD also activates the intrarenal renin-angiotensin system, generating intratubular angiotensin II to promote distal Na+ reabsorption. High dietary Na+ intake in CKD contributes to Na+ retention by aldosterone-independent activation of the mineralocorticoid receptor mediated through Rac1. High dietary Na+ also produces an inflammatory response mediated by T helper 17 cells and cytokines increasing distal Na+ transport. CKD is often accompanied by proteinuria, which contains plasmin capable of activating the epithelial Na+ channel. Thus, CKD causes both local and systemic changes that together promote distal nephron Na+ reabsorption and salt-sensitive hypertension. Future studies should address remaining knowledge gaps, including the relative contribution of each mechanism, the influence of sex, differences between stages and etiologies of CKD, and the clinical relevance of experimentally identified mechanisms. Several pathways offer opportunities for intervention, including with dietary Na+ reduction, distal diuretics, renin-angiotensin system inhibitors, mineralocorticoid receptor antagonists, and K+ or H+ binders.

Prediction and measurement of diuretic responsiveness after oral administration of furosemide to healthy dogs and dogs with congestive heart failure

Background

In human patients, cumulative urine volume (uVol) and urine sodium (uNa) can be predicted using spot urine samples and these quantitative measures help detect low diuretic responsiveness (LDR).

Hypothesis/objectives

Formulas using spot urine samples predict cumulative uVol and uNa output after oral administration of furosemide to dogs.

Animals

Eight healthy dogs, 6 dogs with congestive heart failure (CHF).

Methods

Prospective interventional study. Spot urine samples at 180 and 270 minutes after furosemide (3 mg/kg PO) were used to predict cumulative uVol and uNa output over 7 hours. Differentiation of dogs fulfilling predefined criteria for LDR was examined using receiver operating characteristic (ROC) curves.

Results

Predicted uNa output at 180 minutes (r_s = 0.763, [95% confidence interval [CI], 0.375‐0.923], P = .002) and 270 minutes (r = 0.816, [95% CI, 0.503‐0.940], P < .001) was highly correlated to 7‐hour uNa output. Predicted uVol at 180 minutes (r = 0.598, [95% CI, 0.098‐0.857], P = .02) and 270 minutes (r = 0.791, [95% CI, 0.450‐0.931], P < .001) was moderately correlated to 7‐hour uVol. Predicted uNa using 180‐minute (area under the curve [AUC], 0.933 [95% CI, 0.804‐1.000]) and 270‐minute (AUC, 0.911 [95% CI, 0.756‐1.000]) samples identified dogs with LDR (n = 5) with high accuracy.

Conclusions and Clinical Importance

Urinary Na excretion and uVol are complementary but distinct aspects of diuretic responsiveness in dogs. Quantification of diuretic responsiveness in the clinical setting opens new diagnostic, treatment, and monitoring strategies.

Mechanisms of Diuretic Resistance Study: design and rationale

INTRODUCTION

Diuretic resistance is a common complication impairing decongestion during hospitalization for acute decompensated heart failure (ADHF). The current understanding of diuretic resistance mechanisms in ADHF is based upon extrapolations from other disease states and healthy volunteers. However, accumulating evidence suggests that the dominant mechanisms in other populations have limited influence on diuretic response in ADHF. Additionally, the ability to rapidly and reliably diagnose diuretic resistance is inadequate using currently available tools.

AIMS

The Mechanisms of Diuretic Resistance (MDR) Study is designed to rigorously investigate the mechanisms of diuretic resistance and develop tools to rapidly predict diuretic response in a prospective cohort hospitalized with ADHF.

METHODS

Study assessments occur serially during the ADHF hospitalization and after discharge. Each assessment includes a supervised 6-hour urine collection with baseline blood and timed spot urine collections following loop diuretic administration. Patient characteristics, medications, physical exam findings, and both in-hospital and post-discharge HF outcomes are collected. Patients with diuretic resistance are eligible for a randomized sub-study comparing an increased loop diuretic dose with combination diuretic therapy of loop diuretic plus chlorothiazide.

CONCLUSIONS

The Mechanisms of Diuretic Resistance Study will establish a prospective patient cohort and biorepository to investigate the mechanisms of diuretic resistance and urine biomarkers to rapidly predict loop diuretic resistance.

Systemic Intake of Proton Pump Inhibitors and Selective Serotonin Reuptake Inhibitors May Be Associated With Implant Failure

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

Medication-related dental implant failure: Systematic review and meta-analysis. Chappuis V, Avila-Ortiz G, Araújo MG, Monje A. Clin Oral Implants Res 2018;29 Suppl 16:55-68.

SOURCE OF FUNDING

None. The authors declared no conflict of interest.

TYPE OF STUDY/DESIGN

Systematic review with meta-analysis.

Structure of the Regulatory Cytosolic Domain of a Eukaryotic Potassium-Chloride Cotransporter

Cation-chloride cotransporters (CCCs) regulate the movement of chloride across membranes, controlling physiological processes from cell volume maintenance to neuronal signaling. Human CCCs are clinical targets for existing diuretics and potentially additional indications. Here, we report the X-ray crystal structure of the soluble C-terminal regulatory domain of a eukaryotic potassium-chloride cotransporter, Caenorhabditis elegans KCC-1. We observe a core α/β fold conserved among CCCs. Using structure-based sequence alignment, we analyze similarities and differences to the C-terminal domains of other CCC family members. We find that important regulatory motifs are in less-structured regions and residues important for dimerization are not widely conserved, suggesting that oligomerization and its effects may vary within the larger family. This snapshot of a eukaryotic KCC is a valuable starting point for the rational design of studies of cellular chloride regulation.

A narrative review of pharmacologic de-resuscitation in the critically ill

Despite evidence highlighting harms of fluid overload, minimal guidance exists on counteraction via utilization of diuretics in the de-resuscitation phase. While diuretics have been shown to decrease net volume and improve clinical outcomes in the critically ill, a lack of standardization surrounding selection of diuretic regimen or monitoring of de-resuscitation exists. Current monitoring parameters of de-resuscitation often rely on clinical signs of fluid overload, end organ recovery and other biochemical surrogate markers which are often deemed unreliable. The majority of evidence suggests that achieving a net-negative fluid balance within 72 h after shock resolution may be of benefit; however, approaches to such goal are uncertain. Loop diuretics are a widely available type of diuretic for removal of volume in patients with sufficient kidney function, with the potential for adjunct diuretics in special circumstances. At present, administration of diuretics within the broad critically ill population fails to find uniformity and often efficacy. Given the lack of randomized controlled trials in this susceptible population, we aim to provide a thorough therapeutic understanding of diuretic pharmacotherapy which is necessary in order to achieve desired goal of fluid balance and improve overall outcomes.

Torasemide versus furosemide in treatment of heart failure: A systematic review and meta-analysis of randomized controlled trials

AIM

Diuretics are a cornerstone in treatment of heart failure (HF). Torasemide is a loop diuretic with a potential advantage over other diuretics. We aim to meta-analyse and compare the effect of torasemide with furosemide in HF patients.

METHODS

A comprehensive literature search using 12 databases including PubMed, Scopus, and Web of Science was performed. All randomized controlled trials (RCTs) comparing furosemide and torasemide in HF patients were included and meta-analysed. We assessed the risk of bias using Cochrane Collaboration's tool. The protocol was registered in PROSPERO (CRD42016046112).

RESULTS

Eighteen RCTs with 1598 patients were included. There was a significant difference between torasemide 20 mg and furosemide 40 mg in increasing the urine volume (standard difference of the mean (SDM) [95% confidence interval] = -0.78 [-1.52 to -0.053], P = .036). Torasemide 10 mg and 10 to 20 mg have a significant effect on potassium excretion in comparison with furosemide 25 to 40 mg (P = .018 and .023, respectively). In general, torasemide and furosemide have no significant difference in mortality, edema improvement, weight loss, heart rate, and reducing systolic/diastolic blood pressure. However, oral torasemide has a significant lower hospital stay P < .001 and superior effect in improving ejection fraction P = .029.

CONCLUSION

Although not all results are statistically significant, torasemide has potential advantages on multiple aspects of HF management when compared with furosemide. More studies are needed to clarify these effects.

Is Inhaled Furosemide a Potential Therapeutic for COVID-19?

The potentially lethal infection caused by the novel Severe Acute Respiratory Disease Coronavirus-2 (SARS-CoV-2) has evolved into a global crisis. Following the initial viral infection is the host inflammatory response that frequently results in excessive secretion of inflammatory cytokines (e.g., IL-6 and TNFα), developing into a self-targeting, toxic "cytokine storm" causing critical pulmonary tissue damage. The need for a therapeutic that is available immediately is growing daily but the de novo development of a vaccine may take years. Therefore, repurposing of approved drugs offers a promising approach to address this urgent need. Inhaled furosemide, a small molecule capable of inhibiting IL-6 and TNFα, may be an agent capable of treating the Coronavirus Disease 2019 cytokine storm in both resource-rich and developing countries. Furosemide is a "repurpose-able" small molecule therapeutics, that is safe, easily synthesized, handled, and stored, and is available in reasonable quantities worldwide.