Diuretic strategies in patients with resistance to loop-diuretics in the intensive care unit: A retrospective study from the MIMIC-III database

Combination Diuretic Therapy With Thiazides: A Systematic Review on the Beneficial Approach to Overcome Refractory Fluid Overload in Heart Failure

Heart failure (HF) is a notable public health issue, and intravenous loop diuretics are frequently employed to address acute decompensated heart failure (ADHF) and alleviate symptoms of congestion. However, prolonged use of loop diuretics can lead to drug resistance, and some patients experience refractory volume overload that does not respond to treatment. Sequential nephron blockade, which involves combining loop and thiazide diuretics, has been proposed as a strategy to overcome diuretic resistance and improve fluid overload management. This systematic review aims to critically evaluate the effectiveness and safety of this combination diuretic therapy. Following the directives detailed in the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive search was conducted. Eligibility criteria were established to select relevant studies, including the requirement for studies to be conducted on human subjects and published as free full-text papers in English within the last 10 years. Several databases were searched using a combination of Medical Subject Heading (MeSH) phrases and keywords related to heart failure, loop diuretics, and thiazide diuretics. The search yielded 948 references, and after screening titles, abstracts, and full-text papers, eight final studies (five observational studies and three randomized control trials) were included in the review. Based on the findings of this systematic review, there is substantial evidence to endorse the efficacy of combination diuretic therapy of loop and thiazide diuretics in augmenting diuresis and enhancing outcomes for patients who exhibit insufficient responses to single-agent diuretics. Additionally, the review provides valuable insights about the timing and type of diuretics to use, helping clinicians make informed therapeutic decisions. However, to ensure patient safety and well-being, it is imperative to take into account the potential for electrolyte disturbances and impacts on renal function, necessitating diligent and vigilant monitoring as well as effective management strategies. In light of these findings, further research is warranted to optimize the dosing regimens and to delve deeper into the long-term safety and efficacy of combination therapy. Such research endeavors will undoubtedly contribute to refining treatment approaches and advancing patient care in the field of HF management.

A Holistic View of Advanced Heart Failure

Advanced heart failure (HF) may occur at any level of left ventricular (LV) ejection fraction (LVEF). The latter, which is widely utilized for the evaluation of LV systolic performance and treatment guidance of HF patients, is heavily influenced by LV size and geometry. As the accurate evaluation of ventricular systolic function and size is crucial in patients with advanced HF, the LVEF should be supplemented or even replaced by more specific indices of LV function such as the systolic strain and cardiac power output and size such as the LV diastolic diameters and volumes. Conventional treatment (cause eradication, medications, devices) is often poorly tolerated and fails and advanced treatment (mechanical circulatory support [MCS], heart transplantation [HTx]) is required. The effectiveness of MCS is heavily dependent on heart size, whereas HTx which is effective in the vast majority of the cases is limited by the small donor pool. Expanding the MCS indications to include patients with small ventricles as well as the HTx donor pool are major challenges in the management of advanced HF.

New Insights Into Diuretic Use to Treat Congestion in the ICU: Beyond Furosemide

Diuretics are commonly used in critically ill patients with acute kidney injury (AKI) and fluid overload in intensive care units (ICU), furosemide being the diuretic of choice in more than 90% of the cases. Current evidence shows that other diuretics with distinct mechanisms of action could be used with good results in patients with selected profiles. From acetazolamide to tolvaptan, we will discuss recent studies and highlight how specific diuretic mechanisms could help to manage different ICU problems, such as loop diuretic resistance, hypernatremia, hyponatremia, or metabolic alkalosis. The current review tries to shed some light on the potential use of non-loop diuretics based on patient profile and give recommendations for loop diuretic treatment performance focused on what the intensivist and critical care nephrologist need to know based on the current evidence.

Loop diuretics in adult intensive care patients with fluid overload: a systematic review of randomised clinical trials with meta-analysis and trial sequential analysis

BACKGROUND

Fluid overload is a risk factor for organ dysfunction and death in intensive care unit (ICU) patients, but no guidelines exist for its management. We systematically reviewed benefits and harms of a single loop diuretic, the predominant treatment used for fluid overload in these patients.

METHODS

We conducted a systematic review with meta-analysis and Trial Sequential Analysis (TSA) of a single loop diuretic vs. other interventions reported in randomised clinical trials, adhering to our published protocol, the Cochrane Handbook, and PRISMA statement. We assessed the risks of bias with the ROB2-tool and certainty of evidence with GRADE. This study was registered in the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42020184799).

RESULTS

We included 10 trials (804 participants), all at overall high risk of bias. For loop diuretics vs. placebo/no intervention, we found no difference in all-cause mortality (relative risk (RR) 0.72, 95% confidence interval (CI) 0.49-1.06; 4 trials; 359 participants; I2 = 0%; TSA-adjusted CI 0.15-3.48; very low certainty of evidence). Fewer serious adverse events were registered in the group treated with loop diuretics (RR 0.81, 95% CI 0.66-0.99; 6 trials; 476 participants; I2 = 0%; very low certainty of evidence), though contested by TSA (TSA-adjusted CI 0.55-1.20).

CONCLUSIONS

The evidence is very uncertain about the effect of loop diuretics on mortality and serious adverse events in adult ICU patients with fluid overload. Loop diuretics may reduce the occurrence of these outcomes, but large randomised placebo-controlled trials at low risk of bias are needed.

Diuretic combinations in critically ill patients with respiratory failure: A systematic review and meta-analysis

BACKGROUND

In patients with respiratory failure, loop diuretics remain the cornerstone of the treatment to maintain fluid balance, but resistance is common.

AIM

To determine the efficacy and safety of common diuretic combinations in critically ill patients with respiratory failure.

METHODS

We searched MEDLINE, Embase, Cochrane Library and PROSPERO for studies reporting the effects of a combination of a loop diuretic with another class of diuretic. A meta-analysis using mean differences (MD) with 95% confidence interval (CI) was performed for the 24-h fluid balance (primary outcome) and the 24-h urine output, while descriptive statistics were used for safety events.

RESULTS

Nine studies totalling 440 patients from a total of 6510 citations were included. When compared to loop diuretics alone, the addition of a second diuretic is associated with an improved negative fluid balance at 24 h [MD: -1.06 L (95%CI: -1.46; -0.65)], driven by the combination of a thiazide plus furosemide [MD: -1.25 L (95%CI: -1.68; -0.82)], while no difference was observed with the combination of a loop-diuretic plus acetazolamide [MD: -0.40 L (95%CI: -0.96; 0.16)] or spironolactone [MD: -0.65 L (95%CI: -1.66; 0.36)]. Heterogeneity was high and the report of clinical and safety endpoints varied across studies.

CONCLUSION

Based on limited evidence, the addition of a second diuretic to a loop diuretic may promote diuresis and negative fluid balance in patients with respiratory failure, but only when using a thiazide. Further larger trials to evaluate the safety and efficacy of such interventions in patients with respiratory failure are required.