Comparing the sodium excreting efficacy of furosemide and indapamide combination against furosemide and metolazone combination in congestive heart failure patients: A randomized control trial.

OBJECTIVE: To compare efficacy and safety of indapamide-furosemide combination against metolazone-furosemide combination in refractory heart failure patients. METHODS: The randomised controlled trial was conducted at Rehman Medical Institute, Peshawar, Pakistan, from January 1 to June 30, 2018, and comprised refractory heart failure patients who were randomised into two groups using lottery method Group 1 received intravenous furosemide 40mg Q12hr with metolazone 5mg Q24hr, while group 2 received intravenous furosemide 40mg Q12hr with indapamide 2.5mg Q24hr. Both groups were assessed for urinary sodium excretion, total urine output and decrease in weight on day one, day three and day five of admission. SPSS 22 was used for data analysis. RESULTS: Of the 150 patients, there were 75(50%) in each of the two groups. Mean age in group 1 was 64.8}11.2 years, while it was 66.3}12.9 years in group 2. Both groups showed increased urinary sodium excretion and total urine output (p>0.05). Hypokalaemia was the most common adverse event 66%. Mean hospital stay was not significantly different between the groups (p>0.05). CONCLUSIONS: There was no significant differences between adverse events and efficacy between patients receiving either indapamide-furosemide combination or metolazone-furosemide combination.

Enhancement of diuresis with metolazone in infant paediatric cardiac intensive care patients.

BACKGROUND: Few data are available regarding the use of metolazone in infants in cardiac intensive care. Researchers need to carry out further evaluation to characterise the effects of this treatment in this population. METHODS: This is a descriptive, retrospective study carried out in patients less than a year old. These infants had received metolazone over a 2-year period in the paediatric cardiac intensive care unit at our institution. The primary goal was to measure the change in urine output from 24 hours before the start of metolazone therapy to 24 hours after. Patient demographic variables, laboratory data, and fluid-balance data were analysed. RESULTS: The study identified 97 infants with a mean age of 0.32±0.25 years. Their mean weight was 4.9±1.5 kg, and 58% of the participants were male. An overall 63% of them had undergone cardiovascular surgery. The baseline estimated creatinine clearance was 93±37 ml/minute/1.73 m2. Initially, the participants had received a metolazone dose of 0.27±0.10 mg/kg/day, the maximum dose being 0.43 mg/kg/day. They had also received other diuretics during metolazone initiation, such as furosemide (87.6%), spironolactone (58.8%), acetazolamide (11.3%), bumetanide (7.2%), and ethacrynic acid (1%). The median change in urine output after metolazone was 0.9 ml/kg/hour (interquartile range 0.15-1.9). The study categorised a total of 66 patients (68.0%) as responders. Multivariable analysis identified acetazolamide use (p=0.002) and increased fluid input in the 24 hours after metolazone initiation (p0.05). CONCLUSIONS: Metolazone increased urine output in a select group of patients. Efficacy can be maximised by strategic selection of patients.

Intravenous Chlorothiazide Versus Enteral Metolazone to Augment Loop Diuretic Therapy in the Intensive Care Unit.

BACKGROUND: In cases of loop diuretic resistance in the intensive care unit (ICU), recommendations for a specific second-line thiazide agent are lacking. OBJECTIVE: To compare the effects of intravenous chlorothiazide (CTZ) and enteral metolazone (MET) on urine output (UOP) when added to furosemide monotherapy therapy in critically ill adults. METHODS: This was a retrospective cohort study conducted in the medical, surgical, and cardiothoracic ICUs of a quaternary medical center. The primary outcome was change in UOP induced by the study interventions compared with furosemide alone. Secondary outcomes included onset of diuresis, eventual need for hemodialysis, and incidence of adverse events. RESULTS: A total of 122 patients (58 in CTZ, 64 in MET) were included. When added to furosemide monotherapy, CTZ induced a greater change in UOP at 24 hours compared with MET (2405 vs 1646 mL, respectively; P = 0.01). CTZ also caused a more rapid dieresis: 1463 mL total UOP in the first 6 hours compared with 796 mL in the MET group ( P < 0.01). There were no differences found regarding ICU length of stay, need for renal replacement therapy, or survival to discharge. The CTZ arm required more potassium supplementation to maintain normokalemia (median 100 vs 57 mEq in MET; P = 0.02) and carried a higher cost (mean $97 vs $8, P < 0.01). CONCLUSION: Both CTZ and MET induced significant increases in UOP. CTZ induced a greater and more rapid change and was associated with higher cost and greater need for potassium replacement. Randomized controlled trials are needed to establish whether a preferable thiazide diuretic exists in this setting.

An improved LC-MS/MS method for quantitative determination of metolazone in human plasma and its application to a pharmacokinetic study.

A simple, rapid and accurate liquid chromatography-tandem mass spectrometry method has been developed. After a liquid-liquid extraction procedure, samples were chromatographed on an Agilent TC-C(18) (150 × 4.6 mm, 5 µm) column using an isocratic elution mobile phase composed of methanol and distilled water (70:30, v/v) at a flow rate of 0.5 mL/min. After single-dose administration of 0.5, 1 and 2 mg metolazone, the t(1/2) values were 6.6 ± 2.8, 7.9 ± 1.2 and 7.6 ± 1.9 h, respectively. The pharmacokinetic parameters of multiple doses (1 mg metolazone) were as follows: t(1/2) was 8.9 ± 1.0 h; C(max) was 22.4 ± 5.0 ng/mL; and AUC(0-48) was 156.8 ± 31.6 ng h/mL.

A Systematic Review and Meta-Analysis of Metolazone Compared to Chlorothiazide for Treatment of Acute Decompensated Heart Failure.

Treatment of volume overload in the setting of acute decompensated heart failure (ADHF) is typically achieved through the use of loop diuretics. While they are highly effective, some patients may develop loop diuretic resistance. One strategy to overcome this scenario includes sequential nephron blockade with a thiazide-type diuretic; however, it is unknown which thiazide-type diuretic used in this setting is most effective. A systematic review and meta-analysis were performed to compare the efficacy and safety of chlorothiazide with metolazone as add-on therapy in the setting of loop diuretic resistance for the treatment of ADHF. Literature searches were conducted through PubMed, Google Scholar, and Science Direct from inception through February 2020 using the following search terms alone or in combination: metolazone, chlorothiazide, acute decompensated heart failure, loop diuretic, and urine output. All English-language prospective and retrospective trials and abstracts comparing metolazone to chlorothiazide for the treatment of ADHF were evaluated. Studies were included if they analyzed urine output for at least 24 hours in patients with ADHF. Meta-analysis was conducted to evaluate pooled effect size by using a random-effect model. Primary outcomes included net and total urine output. Secondary outcomes included commonly reported safety outcomes. Four studies comparing the use of metolazone to chlorothiazide as an adjunct to loop diuretics to treat ADHF were included in the evaluation. Metolazone was as effective as chlorothiazide to augment loop diuretic therapy in ADHF in most studies with no pooled difference in net or total urine output. However, there were notable differences in baseline loop diuretic dosing, ejection fraction, renal function, race, and endpoint timing across studies. Adverse effects were commonly observed and included electrolyte abnormalities, change in renal function, and hypotension but were comparable between groups. Metolazone is as effective as chlorothiazide as add-on to loop diuretics in treating ADHF without an increase in safety concerns.

Diuretic Strategies for Loop Diuretic Resistance in Acute Heart Failure: The 3T Trial.

OBJECTIVES: This study compared combination diuretic strategies in acute heart failure (AHF) complicated by diuretic resistance (DR). BACKGROUND: Combination diuretic regimens to overcome loop DR are commonly used but with limited evidence. METHODS: This study was a randomized, double-blinded trial in 60 patients hospitalized with AHF and intravenous (IV) loop DR. Patients were randomized to oral metolazone, IV chlorothiazide, or tolvaptan therapy. All patients received concomitant high-dose IV infusions of furosemide. The primary outcome was 48-h weight loss. RESULTS: The cohort exhibited DR prior to enrollment, producing 1,188 ± 476 ml of urine in 12 h during high-dose loop diuretic therapy (IV furosemide: 612 ± 439 mg/day). All 3 interventions significantly improved diuretic efficacy (p < 0.001). Compared to metolazone (4.6 ± 2.7 kg), neither IV chlorothiazide (5.8 ± 2.7 kg; 1.2 kg [95% confidence interval (CI)]: -2.9 to 0.6; p = 0.292) nor tolvaptan (4.1 ± 3.3 kg; 0.5 kg [95% CI: -1.5 to 2.4; p = 0.456) resulted in more weight loss at 48 h. Median (interquartile range [IQR]) cumulative urine output increased significantly and did not differ among those receiving metolazone (7.78 [IQR: 6.59 to 10.10] l) and chlorothiazide (8.77 [IQR: 7.37 to 10.86] l; p = 0.245) or tolvaptan (9.70 [IQR: 6.36 to 13.81] l; p = 0.160). Serum sodium decreased less with tolvaptan than with metolazone (+4 ± 5 vs. -1 ± 3 mEq/l; p = 0.001), but 48-h spot urine sodium was lower with tolvaptan (58 ± 25 mmol/l) than with metolazone (104 ± 16 mmol/l; p = 0.002) and with chlorothiazide (117 ± 14 mmol/l; p < 0.001). CONCLUSIONS: In this moderately sized DR trial, weight loss was excellent with the addition of metolazone, IV chlorothiazide, or tolvaptan to loop diuretics, without a detectable between-group difference. (Comparison of Oral or Intravenous Thiazides vs. tolvaptan in Diuretic Resistant Decompensated Heart Failure [3T]; NCT02606253).

Outcomes Associated With a Strategy of Adjuvant Metolazone or High-Dose Loop Diuretics in Acute Decompensated Heart Failure: A Propensity Analysis.

Background In acute decompensated heart failure, guidelines recommend increasing loop diuretic dose or adding a thiazide diuretic when diuresis is inadequate. We set out to determine the adverse events associated with a diuretic strategy relying on metolazone or high-dose loop diuretics. Methods and Results Patients admitted to 3 hospitals using a common electronic medical record with a heart failure discharge diagnosis who received intravenous loop diuretics were studied in a propensity-adjusted analysis of all-cause mortality. Secondary outcomes included hyponatremia (sodium <135 mE q/L), hypokalemia (potassium <3.5 mE q/L) and worsening renal function (a ≥20% decrease in estimated glomerular filtration rate). Of 13 898 admissions, 1048 (7.5%) used adjuvant metolazone. Metolazone was strongly associated with hyponatremia, hypokalemia, and worsening renal function ( P<0.0001 for all) with minimal effect attenuation following covariate and propensity adjustment. Metolazone remained associated with increased mortality after multivariate and propensity adjustment (hazard ratio=1.20, 95% confidence interval 1.04-1.39, P=0.01). High-dose loop diuretics were associated with hypokalemia and hyponatremia ( P<0.002) but only worsening renal function retained significance ( P<0.001) after propensity adjustment. High-dose loop diuretics were not associated with reduced survival after multivariate and propensity adjustment (hazard ratio=0.97 per 100 mg of IV furosemide, 95% confidence interval 0.90-1.06, P=0.52). Conclusions During acute decompensated heart failure, metolazone was independently associated with hypokalemia, hyponatremia, worsening renal function and increased mortality after controlling for the propensity to receive metolazone and baseline characteristics. However, under the same experimental conditions, high-dose loop diuretics were not associated with hypokalemia, hyponatremia, or reduced survival. The current findings suggest that until randomized control trial data prove otherwise, uptitration of loop diuretics may be a preferred strategy over routine early addition of thiazide type diuretics when diuresis is inadequate.

Pharmacokinetic study of single- and multiple-dosing with metolazone tablets in healthy Chinese population.

BACKGROUND: Metolazone is a diuretic, saluretic and antihypertensive chemical compound from the quinazoline category that possesses medicinal features similar to those of other thiazide diuretic drugs. However, the pharmacokinetics of metolazone in the Chinese population has rarely been studied. This study aimed to examine the pharmacokinetic characteristics, safety characteristic, and tolerability of metolazone in healthy Chinese subjects after single and multiple doses taken orally as well as the effects that food and gender have on oral metolazone pharmacokinetic parameters. METHODS: An open-label, randomized, and single- and multiple-dosing investigation was performed in healthy Chinese subjects. The investigation included 3 study groups: the 0.5 mg, 1 mg and 2 mg dose groups were the single-dose study groups in the first stage. Eligible volunteers were randomly and orally administered a single 0.5 mg, 1 mg, or 2 mg metolazone tablet. The 0.5 mg dose group was also part of the multiple-dose study group, and the 1 mg dose group was the food-effect study group in the second stage. Human plasma samples were gathered pre-dosing and up to 48 h after dosing. The human plasma sample concentration of metolazone was quantified using a validated liquid chromatography tandem mass spectrometry method. Pharmacokinetic data were calculated by a noncompartmental analysis method using WinNonlin version 6.4. Tolerability was evaluated based on adverse events, medical examination, 12-lead ECG, and other clinical laboratory exams. RESULTS: Thirty eligible subjects (15 men and 15 women) were registered in our investigation and completed all of the study stages. The AUC and Cmax showed dose proportionality after a single dose based on the linear-regression analysis. A comparison of the pharmacokinetic data revealed that the differences between the male and female groups were not statistically significant. The tmax of metolazone was increased by approximately 100% in the fed condition. Metolazone was well tolerated at the tested dose, and no adverse effects were observed. CONCLUSIONS: Single dosing with 0.5 mg, 1 mg, or 2 mg metolazone yielded linear plasma pharmacokinetic properties in healthy Chinese subjects. Multiple oral doses of metolazone did not display significantly different distributions or elimination characteristics from those observed for a single dose. Gender factors did not appear to influence the pharmacokinetic parameter variation of metolazone. The tmax of metolazone increased in the fed condition. Metolazone was well tolerated at the tested dose in this study. TRIAL REGISTRATION: This investigation is retrospectively registered at chictr.org.cn (ChiCTR-IIR-17012929, October 09 2017).

Comparison of metolazone versus chlorothiazide in acute decompensated heart failure with diuretic resistance.

AIMS: Sequential nephron blockade with thiazide-like diuretics is a strategy used to overcome diuretic resistance in acute decompensated heart failure (ADHF), but head-to-head studies are lacking and equipoise exists regarding the preferred thiazide-like diuretic in this setting. We thus compared the effectiveness of oral metolazone versus intravenous (IV) chlorothiazide as add-on therapy to loop diuretics in hospitalized patients with ADHF and renal dysfunction. METHODS: This retrospective cohort study evaluated the efficacy and safety of oral metolazone versus IV chlorothiazide as add-on therapy to loop diuretics in patients hospitalized with ADHF and renal dysfunction. The primary endpoint was net urine output (UOP) at 72 h after initiation of thiazide-like diuretics. Safety endpoints included worsening renal function, hypotension, and electrolyte abnormalities. RESULTS: Fifty-five patients were enrolled with 33 patients receiving metolazone and 22 patients receiving chlorothiazide. There was no difference in median net UOP at 72 h in those receiving metolazone (4828 mL, interquartile range [IQR] 2800-7209 mL) compared to chlorothiazide (3779 mL, IQR 1885-6535 mL) (P = 0.16). There was no difference in hypotension, worsening renal function, hyponatremia, or hypokalemia (P = NS for all comparisons). Hospital length of stay was shorter in the metolazone cohort (median 7 days) compared to chlorothiazide (median 15 days), suggesting the chlorothiazide cohort was likely sicker. CONCLUSION: Sequential nephron blockade with either metolazone or chlorothiazide appears to be efficacious and safe in ADHF, renal dysfunction, and diuretic resistance. Given the considerable cost difference favoring oral metolazone, larger randomized studies are warranted to confirm our findings and to exclude the possibility of confounding by indication.

Efficacy of metolazone and furosemide in children with furosemide-resistant edema.

The effect of a combination of metolazone (0.2 to 0.4 mg/kg/d) and furosemide (2 to 4 mg/kg/d) in achieving a natriuresis and diuresis was measured in 14 children during 22 episodes of edema resistant to furosemide alone. Urinary volume increased from 24 +/- 14 mL/kg/d for patients receiving furosemide to 51 mL/kg/d with combined diuretic therapy (P less than .01), and sodium excretion increased from 34 +/- 5 mEq/d to 155 +/- 176 mEq/d (P less than .01). Two children with severe hypoalbuminemia (serum albumin level less than 1.5 g/dL) and normal renal function, and five children with chronic renal insufficiency (71%) did not respond to combined diuretic therapy. The combination of furosemide and metolazone offers a useful and effective oral therapy in most children with edema resistant to furosemide. Children with chronic renal insufficiency and furosemide-resistant edema did not respond to combination diuretic therapy.

Difficulties of introducing the National Service Framework for heart failure into general practice in the UK.

BACKGROUND: The National Service Framework (NSF) sets standards for the management of heart failure in the UK. Loop diuretics are commonly first prescribed in primary care. Some patients taking these drugs have heart failure and may benefit from other treatments including ACE inhibitors. Accurate diagnosis in primary care is essential for the aims of the NSF to be realised. AIMS: To investigate loop diuretic prescribing in general practice, to analyse recorded clinical features, patient investigations and ACE inhibitor use in this population. METHOD: One thousand three hundred and one patients taking loop diuretics were identified from prescription records of seven general practices. Demographic details, clinical features, investigations and drug treatments were extracted from patient records. RESULTS: The prevalence of loop diuretic prescribing increased with age. Twenty percent of patients were attributed a diagnosis of heart failure but relevant clinical features were recorded in less than 50% of patient records. Open access echocardiography was used in 8.9% of patients. ACE inhibitors were prescribed in 39.8% of patients considered to have heart failure. 18.2% of these were taking the recommended target dose. CONCLUSION: Loop diuretics are prescribed commonly, particularly in the elderly. There is no clear pattern of documented clinical features that leads to prescription of these drugs. Open access echocardiography is rarely used to aid diagnosis. ACE inhibitors are under-prescribed and under-dosed in patients diagnosed with heart failure in this study population.

Age- and gender-related use of low-dose drug therapy: the need to manufacture low-dose therapy and evaluate the minimum effective dose.

OBJECTIVES: Low-dose drug therapy is promoted as a way to maximize benefit and minimize adverse drug effects when prescribing for older adults. This population-based study evaluates the age and sex-related use of two common therapies: thiazide diuretics, where evidence supports the use of low-dose therapy, and beta-blockers, where trials have not evaluated the minimum effective dose. DESIGN: Using linked administrative databases we identified all of the 120,613 persons dispensed a thiazide diuretic therapy and 12,908 myocardial infarction survivors dispensed beta-blocker therapy in Canada's largest province. We used logistic regression models to study the association of age and sex with dispensing of low-dose thiazide diuretic and beta-blocker therapy at doses lower than evaluated in trials. RESULTS: Of 120,613 older people dispensed a thiazide diuretic, 32,372 (26.8%) were dispensed a low dose. Patients 85 years of age or older, relative to the youngest group, were 30% more likely to be dispensed low-dose therapy (OR=1.31; 95% CI, 1.27 to 1.36; P < .001). Women were 8% more likely than men to be dispensed a low-dose thiazide diuretic (OR=1.08; 95% CI, 1.05 to 1.11; P < .001). Of 10,991 myocardial infarction survivors dispensed atenolol, metoprolol, propranolol, or timolol, 9458 (86.1%) were dispensed a lower-than-evaluated dose. Patients 85 years of age or older, relative to those in the youngest group, were more than twice as likely to be dispensed a lower-than-evaluated beta-blocker therapy dose (OR=2.28; 95% CI, 1.74 to 3.04; P < .001). No difference was noted in the use of beta-blocker therapy dose by sex (OR=1.0; 95% CI, .89 to 1.15; P = .95). CONCLUSIONS: Low-dose thiazide diuretic therapy prescribed widely to older people, particularly those of advanced age and women. The vast majority of myocardial infarction survivors were dispensed beta-blocker therapy at lower-than-evaluated doses. These findings highlight the need to manufacture low-dose thiazide diuretic therapy and to evaluate the minimum effective dose of beta-blocker therapy.

Double-blind comparison of losartan, lisinopril, and metolazone in elderly hypertensive patients with previous angiotensin-converting enzyme inhibitor-induced cough.

This study compared the incidence of cough with the angiotensin-converting enzyme (ACE) inhibitor lisinopril and the diuretic metolazone with angiotensin II receptor antagonist losartan in elderly hypertensive patients with previous histories of ACE inhibitor-induced cough. A randomized, double-blind, stratified, parallel-group comparison of lisinopril at 10 mg, losartan at 50 mg, and metolazone at 1 mg, each given once daily for a maximum of 10 weeks, was performed in four hypertension clinics in four centers in two countries. Cough was detected by a questionnaire (the primary end point) given to elderly patients with hypertension, and the cough frequency was quantified by a visual analog scale (a secondary end point). A total of 84 elderly patients with hypertension, all who were nonsmokers with ACe inhibitor-induced cough and were confirmed by lisinopril rechallenge then placebo dechallenge, were randomized to the three treatment groups. The incidence of cough with losartan (18%) was significantly lower than with lisinopril (97%) and similar to that for metolazone (21%). Cough frequency evaluated by the visual analog scale was significantly lower for losartan than for lisinopril and similar to that for metolazone. The specific, selective angiotensin II receptor antagonist losartan is associated with a decrease in the incidence of cough in patients with previous ACE inhibitor-induced cough.

Low-dose diuretic therapy for hypertension.

The efficacy of low dosages of diuretics was evaluated in two studies. In one, 62 (48%) of 130 patients became normotensive with 2.5 mg/day of metolazone. In the other, 28 (49%) of 57 patients became normotensive with 25 mg of chlorthalidone, compared with 12 (22%) of 55 patients given placebo. There was a marked variation in blood pressure response and the occurrence of hypokalemia (less than 3.5 mEq/L of potassium) from center to center and within patient groups in both studies. The mean decrease in serum potassium was between 0.5 and 0.6 mEq/L in the metolazone group and 0.44 mEq/L in the chlorthalidone-treated patients. This degree of hypokalemia is only slightly less than that noted when larger dosages of thiazide diuretics are used (0.6 to 0.7 mEq/L). It is concluded that 2.5 mg/day of metolazone or 25 mg/day of chlorthalidone are effective antihypertensive agents but that blood pressure lowering may be inconsistent at these dosage levels. It is reasonable, therefore, to begin diuretic therapy with low dosages, but larger dosages (5 mg of metolazone or 50 mg of chlorthalidone) should be tried before adding another drug or concluding that diuretic therapy is ineffective if an acceptable blood pressure response is not obtained. The degree of hypokalemia that occurs at lower-dose therapy is variable but may be of less clinical significance than that noted with higher dosages of diuretics in some patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical studies of a new, low-dose formulation of metolazone for the treatment of hypertension.

Two multicenter, double-blind, randomized studies were performed to determine the antihypertensive efficacy and effects on laboratory values of a new, shorter-acting formulation of metolazone in patients with mild to moderate hypertension. After baseline placebo-control periods, 105 patients were randomly assigned to receive single daily doses of either placebo or 0.5, 1.0, or 2.0 mg of the new formulation of metolazone for six weeks in one study, and 164 patients were randomized to receive 0.5, 1.0, or 2.0 mg of the new formulation of metolazone or 2.5 mg of the older, long-acting metolazone in the other. Mean blood pressure reductions in all three metolazone groups were statistically and clinically significant. Blood pressures of 51% to 58% of patients in the 0.5-mg metolazone group were controlled (diastolic blood pressure less than 90 or a fall of greater than or equal to 10 mmHg from baseline). Reductions in mean serum potassium levels were dose-related. We conclude that 0.5 mg of metolazone is safe and effective therapy for hypertension; it will significantly reduce systolic and diastolic blood pressure and minimizes changes in laboratory test values.

Changes in body water compartments with diuretic therapy in infants with chronic lung disease.

The effects of diuretic therapy on body water compartments were studied in preterm infants with chronic lung disease. Gestational age of the infants ranged from 24 to 28 weeks, while the median postnatal age at the time of study was 40 days. Infants were randomized to receive furosemide (1.0 mg/kg/day) alone (n = 5) or combined with metolazone (0.2 mg/kg/day, n = 7) for 4 consecutive days. Treatment in both groups produced a significant decrease (P < 0.05) in extracellular water (ECW) without changes in plasma volume, total body water or body weight. The decrease in ECW with furosemide (503 +/- 28 to 446 +/- 19 ml/kg initial body weight) was of similar magnitude to that seen with combined furosemide plus metolazone (522 +/- 30 to 454 +/- 15 ml/kg initial body weight). Water and electrolyte intakes were similar in both groups and unchanged over the course of the study. These findings suggest that in infants with chronic lung disease, diuretic therapy induces intercompartmental shifts in body water, ultimately decreasing interstitial water while preserving PV. Only combined treatment with furosemide plus metolazone produced a significant increase in urine output, confirming the increased efficacy of combination therapy in inducing diuresis.

[Metolazone in the treatment of advanced therapy-resistant dilated cardiomyopathy]. / Metolazone in der Behandlung fortgeschrittener therapieresistenter dilatativer Kardiomyopathie.

Ten patients (eight male/two female) with advanced dilated cardiomyopathy (NYHA III/IV) and a mean fractional shortening in two-dimensional echocardiogram of 20% (9 to 30%) and a mean sodium excretion of 21 mmol (8 to 40 mmol) per day, pretreated with digoxin, captopril and a mean frusemide-dose of 147 mg (80 to 500 mg) without an effective diuresis, were additional treated with 2.5 to 5 mg oral metolazone daily. All patients had a brisk diuresis within 24 hours and a mean weight loss of 8.9 kg (3 to 20 kg) until discharge. All patients improved considerably by additional metolazone-therapy. Seven patients developed a mild hyponatraemia (122 to 132 mmol/l), seven showed mild (greater than or equal to 3.2 mmol/l) and one had a serious hypokalaemia (2.8 mmol/l); spironolactone-pretreated patients developed no hypokalaemia. Notably none of the patients had serious blood pressure fluctuation or a deterioration of renal function. To avoid severe electrolyte-disturbances, additional metolazone-therapy should be practised in hospital, preferring low-dose metolazone and reducing frusemide-dose under careful biochemical monitoring after diuresis is started.

Combination therapy with low-dose metolazone and furosemide: a "needleless" approach in managing refractory fluid overload in elderly renal failure patients under palliative care.

BACKGROUND AND OBJECTIVE: End-stage renal failure (ESRF) patients under palliative care could live for months or even years after deciding not to start dialysis. They could experience significant symptom burden with recurrent fluid overload due to poor renal reserve. This could imply repeated hospital admissions for parenteral diuretics, which may destabilize their community support and limit their precious time spent with family. Diuretic therapy remains the cornerstone of managing fluid overload, but when per-oral administration become ineffective, parenteral diuretics may cause extra discomfort with potential infective complications. Metolazone, since its introduction in 1970s, has been proven effective in managing refractory heart failure, but whether its potential effect could be applied in ESRF patients not receiving dialysis is awaited to be proven. METHOD: In our case series, we recruited elderly renal failure patients under palliative care with refractory fluid overload resistant to oral furosemide (120-160 mg daily dose), which was successfully managed after addition of low-dose metolazone (2.5-5 mg) for short duration (2-5 days). Reasoning behind not to initiate intravenous diuretics was discussed. RESULTS: All patients show good tolerance to combined diuretics without significant blood pressure fluctuation or electrolytes disturbance. Peripheral and pulmonary edema was clinically improved. Body weight reduction of 2.0-5.0 kg was achieved. CONCLUSION: Our case series support the use of above regimen as a potential alternative in ESRF patients under palliative care, without bearing the parenteral route of treatment burden.

Effect of intensified diuretic therapy on overnight rostral fluid shift and obstructive sleep apnoea in patients with uncontrolled hypertension.

OBJECTIVES: Fluid displacement from the lower extremities to the upper body during sleep is strongly associated with obstructive sleep apnoea in hypertensive patients. The present pathophysiological study tests the hypothesis that intensified diuretic therapy will reduce the apnoea-hypopnoea index and blood pressure of uncontrolled hypertensive patients with obstructive sleep apnoea in proportion to the reduction in overnight change in leg fluid volume. METHODS: Uncontrolled treated hypertensive patients underwent overnight polysomnography and measurement of overnight changes in leg fluid volume and neck circumference. Those with an apnoea-hypopnoea index at least 20 events per hour (n=16) received metolazone 2.5 mg and spironolactone 25 mg daily for 7 days after which the daily dose was doubled for 7 additional days. Baseline testing was again repeated. RESULTS: Intensified diuretic therapy reduced the apnoea-hypopnoea index from 57.7 ± 33.0 to 48.5 ± 28.2 events per hour (P=0.005), overnight change in leg fluid volume from -418.1 ± 177.5 to -307.5 ± 161.9 ml (P<0.001) and overnight change in neck circumference from 1.2 ± 0.6 to 0.7 ± 0.4 cm (P<0.001). There was an inverse correlation between the reduction in overnight change in leg fluid volume and decrease in apnoea-hypopnoea index (r=-0.734, P=0.001). The reduction in overnight change in leg fluid volume was also significantly correlated with the change in morning blood pressure (r=0.708, P=0.002 for SBP; r=0.512, P=0.043 for DBP). CONCLUSION: The findings provide further evidence that fluid redistribution from the legs to the neck during sleep contributes to the severity of obstructive sleep apnoea in hypertension and may be an important link between these two conditions.