Comparative study of dexamethasone premedication regimens with docetaxel chemotherapy in early HER-2 positive breast cancer: A safety net hospital experience

INTRODUCTION

Docetaxel can cause fluid retention reactions (FRRs) and hypersensitivity reactions (HSRs). The manufacturer recommends a multi-day oral dexamethasone premedication to prevent these toxicities, but steroid related side effects and regimen compliance remain a concern. This study aimed to determine if modified dexamethasone premedication regimens resulted in differences in HSRs or FRRs to docetaxel. We also examined side effects of dexamethasone and delays in chemotherapy.

METHODS

A retrospective chart review was conducted on 82 early breast cancer patients treated with docetaxel. Three steroid regimens were examined: IV 20 mg single-dose dexamethasone, or IV 12 mg dexamethasone with either dexamethasone 8 mg BID for three days starting the day before chemotherapy or dexamethasone 4 mg BID for three days following chemotherapy. Adverse effects, delays in chemotherapy, and reasons for delays in chemotherapy were recorded.

RESULTS

The incidence and severity of FRRs and HSRs was low, with less than 10% incidence of HSRs or FRRs in any group. Delays were most common in the group receiving dexamethasone 8 mg BID for 3 days starting the day before chemotherapy (63.3%) (p < 0.05) and were most commonly due to patient noncompliance (26%).

CONCLUSION

A single dose of intravenous dexamethasone alone or followed by lower doses of oral dexamethasone may improve patient compliance and avoid delays in chemotherapy, without an increase in docetaxel toxicity.

Isolate Whey Protein Promotes Fluid Balance and Endurance Capacity Better Than Isolate Casein and Carbohydrate-Electrolyte Solution in a Warm, Humid Environment

Protein ingestion is known to enhance post-exercise hydration. Whether the type of protein (i.e., whey, casein) can alter this response is unknown. Accordingly, this study aimed to compare the effects of the addition of milk-derived whey isolate or casein protein to carbohydrate-electrolyte (CE) drinks on post-exercise rehydration and endurance capacity. Thirty male soldiers (age: 24 ± 2.1 y; VO2max: 49.3 ± 4.7 mL/kg/min) were recruited. Upon losing ~2.2% of body mass by running in warm and humid conditions (32.3 °C, 76% relative humidity [RH]), participants ingested either a CE solution (66 g/L carbohydrate [CHO]), or CE plus isolate whey protein (CEW, 44 g/L CHO, 22 g/L isolate whey), or CE plus isolate casein protein (CEC, 44 g/L CHO, 22 g/L isolate casein) beverage in a volume equal to 150% of body mass loss. At the end of the 3 h rehydration period, a positive fluid balance was higher with CEW (0.22 L) compared to CEC (0.19 L) and CE (0.12 L). Overall mean fluid retention was higher in CEW (80.35%) compared with the CE (76.67%) and CEC trials (78.65%). The time of the endurance capacity test [Cooper 2.4 km (1.5 miles) run test] was significantly higher in CEC (14.25 ± 1.58 min) and CE [(12.90 ± 1.01 min; (p = 0.035)] than in CEW [(11.40 ± 1.41 min); (p = 0.001)]. The findings of this study indicate that the inclusion of isolate whey protein in a CE solution yields superior outcomes in terms of rehydration and enhanced endurance capacity, as compared to consuming the CE solution alone or in conjunction with isolate casein protein.

The sodium glucose co-transporter 2 inhibitor dapagliflozin ameliorates the fluid-retaining effect of the endothelin A receptor antagonist zibotentan

BACKGROUND

Endothelin A receptor antagonists (ETARA) slow chronic kidney disease (CKD) progression but their use is limited due to fluid retention and associated clinical risks. Sodium-glucose co-transporter 2 inhibitors (SGLT2i) cause osmotic diuresis and improve clinical outcomes in CKD and heart failure. We hypothesized that co-administration of the SGLT2i dapagliflozin with the ETARA zibotentan would mitigate the fluid retention risk using hematocrit (Hct) and bodyweight as proxies for fluid retention.

METHODS

Experiments were performed in 4% salt fed WKY rats. First, we determined the effect of zibotentan (30, 100 or 300 mg/kg/day) on Hct and bodyweight. Second, we assessed the effect of zibotentan (30 or 100 mg/kg/day) alone or in combination with dapagliflozin (3 mg/kg/day) on Hct and bodyweight.

RESULTS

Hct at Day 7 was lower in zibotentan versus vehicle groups [zibotentan 30 mg/kg/day, 43% (standard error 1); 100 mg/kg/day, 42% (1); and 300 mg/kg/day, 42% (1); vs vehicle, 46% (1); P < .05], while bodyweight was numerically higher in all zibotentan groups compared with vehicle. Combining zibotentan with dapagliflozin for 7 days prevented the change in Hct [zibotentan 100 mg/kg/day and dapagliflozin, 45% (1); vs vehicle 46% (1); P = .44] and prevented the zibotentan-driven increase in bodyweight (zibotentan 100 mg/kg/day + dapagliflozin 3 mg/kg/day = -3.65 g baseline corrected bodyweight change; P = .15).

CONCLUSIONS

Combining ETARA with SGLT2i prevents ETARA-induced fluid retention, supporting clinical studies to assess the efficacy and safety of combining zibotentan and dapagliflozin in individuals with CKD.

Mineralocorticoid receptor-independent activation of ENaC in bile duct ligated mice

Sodium and fluid retention in liver disease is classically thought to result from reduced effective circulating volume and stimulation of the renin-angiotensin-aldosterone system (RAAS). Aldosterone dives Na+ retention by activating the mineralocorticoid receptor and promoting the maturation and apical surface expression of the epithelial Na+ channel (ENaC), found in the aldosterone-sensitive distal nephron. However, evidence of fluid retention without RAAS activation suggests the involvement of additional mechanisms. Liver disease can greatly increase plasma and urinary bile acid concentrations and have been shown to activate ENaC in vitro. We hypothesize that elevated bile acids in liver disease activate ENaC and drive fluid retention independent of RAAS. We therefore increased circulating bile acids in mice through bile duct ligation (BDL) and measured effects on urine and body composition, while using spironolactone to antagonize the mineralocorticoid receptor. We found BDL lowered blood [K+] and hematocrit, and increased benzamil-sensitive natriuresis compared to sham, consistent with ENaC activation. BDL mice also gained significantly more body water. Blocking ENaC reversed fluid gains in BDL mice but had no effect in shams. In isolated collecting ducts from rabbits, taurocholic acid stimulated net Na+ absorption but had no effect on K+ secretion or flow-dependent ion fluxes. Our results provide experimental evidence for a novel aldosterone-independent mechanism for sodium and fluid retention in liver disease which may provide additional therapeutic options for liver disease patients.

A Case of Docetaxel-Induced Left Ventricular Outflow Tract Obstruction

Docetaxel, a taxoid chemotherapy agent, may induce fluid retention. We present a case of metastatic breast cancer in which high output caused by docetaxel-induced fluid retention resulted in heart failure due to left ventricular outflow tract (LVOT) obstruction. A 58-year-old woman presented with exertional dyspnea and anasarca. The jugular venous pressure was elevated, and the carotid pulse was pulsus bisferiens with a spike-and-dome configuration. On auscultation, a mid-late systolic murmur that did not radiate to the neck but increased with the Valsalva maneuver was noted. Echocardiography revealed a left ventricular ejection fraction of 63% with systolic anterior motion (SAM) of the mitral valve, resulting in LVOT obstruction with a resting pressure gradient of 64 mmHg and moderate to severe mitral regurgitation. Treatment with carvedilol, trichlormethiazide, and an increased dose of furosemide gradually improved her symptoms, physical findings, and echocardiographic abnormalities. This case highlights the importance of recognizing high-output heart failure along with LVOT obstruction in patients scheduled to receive docetaxel.

Endothelin receptor antagonists in kidney protection for diabetic kidney disease and beyond?

The burden of chronic kidney disease is increasing worldwide, largely due to the increasing global prevalence of diabetes mellitus and hypertension. While renin angiotensin system inhibitors and sodium-glucose cotransporter two inhibitors are the management cornerstone for reducing kidney and cardiovascular complications in patients with diabetic and non-diabetic kidney disease (DKD), they are partially effective and further treatments are needed to prevent the progression to kidney failure. Endothelin receptor antagonism represent a potential additional therapeutic option due to its beneficial effect on pathophysiological processes involved in progressive kidney disease including proteinuria, which are independently associated with progression of kidney disease. This review discusses the biological mechanisms of endothelin receptor antagonists (ERA) in kidney protection, the efficacy and safety of ERA in randomised controlled trials reporting on kidney outcomes, and its potential future use in both diabetic and non-DKDs.

Edematous wall thickening of the gallbladder induced by hyperthyroidism: A case report

RATIONALE

Hyperthyroidism, such as Basedow disease, causes fluid retention, although the common cause is volume overload due to congestive heart failure. In addition, hyperthyroidism and Basedow disease are known to cause pulmonary hypertension. Edematous thickening of the gallbladder wall is caused by venous blood congestion. The feature of edematous wall thickening of the gallbladder on abdominal computed tomography (CT) is subserosal edema and is often accompanied by a periportal collar sign.

PATIENT CONCERNS

A 30-year-old woman was referred to our hospital because of liver dysfunction, edematous gallbladder wall thickening, and fluid retention. In addition, the patient developed hyperthyroidism and heart failure. Enhanced abdominal CT revealed edematous wall thickening of the gallbladder and a periportal collar sign.

DIAGNOSIS

We suspected that fluid retention and congestion were caused by hyperthyroidism and Basedow disease.

INTERVENTIONS

On admission, we started thiamazole therapy for Basedow disease, and her thyroid hormone levels normalized.

OUTCOMES

Abdominal CT revealed disappearance of edematous wall thickening of the gallbladder, which was likely associated with an improvement in thyroid function. The patient was discharged 10 days after admission.

LESSONS

We encountered a case of hyperthyroidism and Basedow disease accompanied by edematous wall thickening of the gallbladder and various fluid retentions as the first symptoms. Such edematous wall thickening of the gallbladder and various fluid retentions were reduced, together with the improvement of hyperthyroidism.

Sodium Chloride, Migraine and Salt Withdrawal: Controversy and Insights

This paper examines evidence implicating migraine headache as a withdrawal symptom of excessive sodium chloride intake. Emerging research in food addiction posits that food and drug addictions share common features, such as withdrawal symptoms. Salt (sodium chloride) meets the criteria for the diagnosis of substance dependence, including withdrawal in which the substance is used to relieve withdrawal symptoms. The premonitory symptoms of migraine include food cravings for salty foods, which can alleviate migraine pain. Edema, possibly related to large amounts of salt consumed in binge eating, can cause approximately four pounds of retained fluid. This amount of fluid is similar to the fluid retained before the onset of migraine headache, which may be accompanied by polyuria. This paper proposes that inhibited withdrawal from highly processed food intake, rich in salt, mediates an association between increased sodium chloride intake and relief from migraine headache pain. The relief from withdrawal symptoms could also be a mediating factor that explains the controversial findings inversely associating dietary sodium intake with migraine history. Moreover, the withdrawal of retained sodium and edema related to the use of nonsteroidal anti-inflammatory drugs may elucidate a potential mechanism in medication overuse headache. Further research is needed to investigate the pain experienced from sodium chloride withdrawal in migraine headache.

Cyclic Progesterone Therapy in Androgenic Polycystic Ovary Syndrome (PCOS)-A 6-Month Pilot Study of a Single Woman's Experience Changes

Background and Objectives: Women with androgenic Polycystic Ovary Syndrome (PCOS) have increased endometrial cancer risk that cyclic progesterone will prevent; it may also reverse PCOS’s neuroendocrine origins. This pilot study’s purpose was to document 6-month experience changes in a woman with PCOS taking cyclic progesterone therapy because she was intolerant of combined hormonal contraceptive therapy, the current PCOS standard of care. A 31-year-old normal-weight woman with PCOS had heavy flow, irregular cycles, and was combined hormonal contraceptives-intolerant. She was prescribed cyclic oral micronized progesterone (OMP) (300 mg/h.s. cycle days 14–27). She kept Menstrual Cycle Diary© (Diary) records, starting with the 1st treatment cycle for six cycles; she was on no other therapy. Statistical analysis a priori hypothesized progesterone decreases high estradiol (E2) experiences (flow, cervical mucus, fluid retention, front-of-the-breast tenderness and anxiety); analysis focused on these. Our objectives: (1) changes from cycles 1 to 6 in E2-related experiences; and (2) follicular phase E2-related changes from cycle 1 (no therapy) to cycles 3 and 6. Materials and Methods: Data from consecutive Diaries were entered into an SPSS database and analyzed by Wilcoxon Signed Rank Test (Objective #1) within-person whole cycle ordinal data, and (Objective #2 follicular phase) repeated measures ANOVA. Results: Cyclic OMP was associated with regular, shorter cycles (±SD) (28.2 ± 0.8 days). Comparison of cycles 1–6 showed decreased fluid retention (p = 0.001), breast tenderness (p = 0.002), and cervical mucus (p = 0.048); there were no changes in flow or anxiety. Fluid retention in the follicular phase also significantly decreased over time (F (1.2, 14.7) = 6.7, p = 0.017). Conclusions: Pilot daily Diary data suggest women with PCOS have improved everyday experiences on cyclic progesterone therapy. Larger prospective studies with more objective outcomes and randomized controlled trials of this innovative PCOS therapy are needed.

Preoperative Concentrated Urine Increases the Incidence of Plasma Creatinine Elevation After Major Surgery

Background: Postoperative elevation of plasma creatinine is a frequent complication to major surgery. A rise by 50% fulfills the criterion for Acute Kidney Injury. We studied the relationship between concentrated urine before surgery, which is usually a sign of chronically low intake of water, and the perioperative change in plasma creatinine.

Methods: The creatinine concentration was measured in plasma and urine just before and at 6 h, 1 day, and 2 days after major abdominal surgery in a consecutive series of 181 patients. Receiver operating curve analysis was used to find the optimal cut-off to separate concentrated from diluted urine.

Results: Urine creatinine of 11.3 mmol/L before the surgery started was exceeded in one third of the patients and associated with greater increase in plasma creatinine at 6 h (median 21 vs. 10%) and at 1 day postoperatively (21 vs. 7%; P < 0.0001). Elevation of plasma creatinine of >25% occurred in 41% and 19% in those with high and low urine creatinine, respectively (P < 0.001) and an increase by >50% in 16% and 10% (P = 0.27). Patients with high urine creatinine before surgery failed to further concentrate their urine during the perioperative period, which is normally associated with intensified renal fluid conservation.

Conclusion: High urinary concentration of creatinine before surgery should be considered as a risk factor for postoperative elevation of plasma creatinine. The mechanism is probably that the renal threshold is then more easily reached.

Safety of low-dose oral minoxidil for hair loss: A multicenter study of 1404 patients

BACKGROUND

The major concern regarding the use of low-dose oral minoxidil (LDOM) for the treatment of hair loss is the potential risk of systemic adverse effects.

OBJECTIVE

To describe the safety of LDOM for the treatment of hair loss in a large cohort of patients.

METHODS

Retrospective multicenter study of patients treated with LDOM for at least 3 months for any type of alopecia.

RESULTS

A total of 1404 patients (943 women [67.2%] and 461 men [32.8%]) with a mean age of 43 years (range 8-86) were included. The dose of LDOM was titrated in 1065 patients, allowing the analysis of 2469 different cases. The most frequent adverse effect was hypertrichosis (15.1%), which led to treatment withdrawal in 14 patients (0.5%). Systemic adverse effects included lightheadedness (1.7%), fluid retention (1.3%), tachycardia (0.9%), headache (0.4%), periorbital edema (0.3%), and insomnia (0.2%), leading to drug discontinuation in 29 patients (1.2%). No life-threatening adverse effects were observed.

LIMITATIONS

Retrospective design and lack of a control group.

CONCLUSION

LDOM has a good safety profile as a treatment for hair loss. Systemic adverse effects were infrequent and only 1.7% of patients discontinued treatment owing to adverse effects.

Three-dimensional shape-conformation performances of wound dressings tested in a robotic sacral pressure ulcer phantom

Effective exudate retention by dressings requires close and intimate dressing‐wound contact, immediately and continuously after the dressing application. Any dressing‐wound spaces may allow for build‐up of non‐retained fluids, causing exudate pooling which forms a favourable environment for pathogen growth. Maceration may follow if the pooled exudates spread to peri‐wound skin. Dressings with a claimed 3D‐shape‐conformation technology are commercially available; however, their effectiveness in minimising dressing‐wound gaps has never been scientifically investigated. We present a novel bioengineering methodology for testing the effectiveness of such 3D‐shape‐conformation dressings, using our recently reported robotic phantom system of a sacral pressure ulcer. By means of 3D laser scanning and bespoke software, we reconstructed dressing shapes after simulated use and calculated the goodness‐of‐fit between each dressing (swelled to near‐saturation) and the corresponding wound geometry. Two dressing sizes (10 × 10 cm and 12.5 × 12.5 cm) and two wound depths (2.5 or 2 cm) were considered. All the tested dressings were far from reaching good contact with the (simulated) wounds: Approximately one‐third of the wound volume and nearly half of the wound surface were not in contact with the swelled dressings. Our present findings question whether 3D‐shape‐conformation dressings are effective, by revealing their swelling behaviour which was previously unknown.

Early Detection of Fluid Retention in Patients with Advanced Heart Failure: A Review of a Novel Multisensory Algorithm, HeartLogicTM

Heart failure (HF) hospitalisations due to decompensation are associated with shorter life expectancy and lower quality of life. These hospitalisations pose a significant burden on the patients, doctors and healthcare resources. Early detection of an upcoming episode of decompensation may facilitate timely optimisation of the ambulatory medical treatment and thereby prevent heart-failure-related hospitalisations. The HeartLogic^TM algorithm combines data from five sensors of cardiac implantable electronic devices into a cumulative index value. It has been developed for early detection of fluid retention in heart failure patients. This review aims to provide an overview of the current literature and experience with the HeartLogic^TM algorithm, illustrate how the index can be implemented in daily clinical practice and discuss ongoing studies and potential future developments of interest.

Tyrosine kinase inhibitor-induced hypertension-marker of anti-tumour treatment efficacy or cardiovascular risk factor?

Tyrosine kinase receptor inhibitors (TKIs) are a relatively new class of targeted anti-cancer agents with vascular endothelial growth factor signalling pathway-inhibiting properties. Hypertension is recognized as one of the most common adverse effects of this anti-angiogenic therapy and is the consequence of reduced production of vasodilatory nitric oxide and reduced prostacyclin production as well as increased production of vasoconstrictive endothelin-1. TKI-induced hypertension is dose dependent and it has been suggested as a marker of treatment effectiveness. In this issue, Saito et al. report the incidence of treatment-related hypertension in patients treated with lenvatinib, a newer TKI, for non-resectable hepatocellular carcinoma. The authors demonstrate that a subset of TKI-treated patients develop fluid retention 3 weeks after treatment initiation as a consequence of lower urinary sodium excretion and thus provides insights into the pathogenesis of blood pressure elevation in the second phase. These findings contribute to a better understanding of TKI-associated hypertension and help in choosing the most appropriate antihypertensive agents in this setting. Active control of hypertension may help more patients benefit from longer TKI therapy, possibly resulting in better cancer outcomes.

Efficacy of Ingesting an Oral Rehydration Solution after Exercise on Fluid Balance and Endurance Performance

This study investigated the efficacy of ingesting an oral rehydration solution (DD) that has a high electrolyte concentration after exercise on fluid balance and cycling performance in comparison with a sports drink (SD) and water (WA). Nine healthy males aged 24 ± 2 years (mean ± SD), with peak oxygen uptake (VO₂ peak) 55 ± 6 mL·kg⁻¹·min⁻¹ completed three experimental trials in a randomised manner ingesting WA, SD (carbohydrates: 62 g·L⁻¹, sodium: 31 ± 3 mmol·L⁻¹) or DD (carbohydrates: 33 g·L⁻¹, sodium: 60 ± 3 mmol·L⁻¹). On all trials, fluid was ingested during 75 min cycling at 65% VO₂ peak (temperature: 30.4 ± 0.3 °C, relative humidity: 76 ± 1%, simulated wind speed: 8.0 ± 0.6 m·s⁻¹) and during 2 h of recovery (temperature: 23.0 ± 1.0 °C, relative humidity: 67 ± 2%), with the total volume equivalent to 150% of sweat loss during the ride. A 45 min pre-load cycling time trial at a 65% VO₂ peak followed by a 20 km time trial was conducted after a further 3 h of recovery. Fluid retention was higher with DD (30 ± 15%) than WA (−4 ± 19%; p < 0.001) and SD (10 ± 15%; p = 0.002). Mean ratings of palatability were similar among drinks (WA: 4.25 ± 2.60; SD: 5.61 ± 1.79; DD: 5.40 ± 1.58; p = 0.33). Although time trial performance was similar across all three trials (WA: 2365 ± 321 s; SD: 2252 ± 174 s; DD: 2268 ± 184 s; p = 0.65), the completion time was faster in eight participants with SD and seven participants with DD than with WA. Comparing SD with DD, completion time was reduced in five participants and increased in four participants. DD was more effective at restoring the fluid deficit during recovery from exercise than SD and WA without compromising the drink’s palatability with increased sodium concentration. Most individuals demonstrated better endurance exercise time trial performance with DD and SD than with WA.

Mechanisms in fluid retention - towards a mutual concept

Fluid retention is a common and challenging condition in daily clinical practice. The normal fluid homoeostasis in the human body is based on accurately counter-balanced physiological mechanisms. When compromised fluid retention occurs and is seen in pathophysiologically different conditions such as liver cirrhosis, heart and kidney failure, and in preeclampsia. These conditions may share pathophysiological mechanisms such as functional arterial underfilling, which seems to be a mutual element in cirrhosis, cardiac failure, cardiorenal and hepatorenal syndromes, and in pregnancy. However, there are also distinct differences and it is still unclear whether kidney dysfunction or arterial underfilling is the initiating factor of fluid retention or if they happen simultaneously. This review focuses on similarities and differences in water retaining conditions and points to areas where important knowledge is still needed.

automated pump-a prospective randomized study

BACKGROUND

Soft tissue fluid retention due to irrigation is relatively common after shoulder arthroscopy. The objective of this study was to compare fluid retention of 2 irrigation systems of shoulder arthroscopy: gravity flow irrigation and automated pump.

METHODS

Patients undergoing shoulder arthroscopy were enrolled prospectively and randomized into 2 groups using gravity flow system (GFS) or automated pump system (APS) for irrigation. Net weight gain was the primary outcome measurement to determine periarticular fluid retention. Change in deltoid diameter and postoperative pain were also compared.

RESULTS

Forty-two patients were included in the study. There were no statistically significant differences between the GFS and APS groups regarding demographics, surgical procedures, duration of surgery, or the amount of irrigation fluid used. The APS group had greater weight gain per hour (1.46 ± 0.36 kg/h vs. 1.1 ± 0.38 kg/h) than the GFS group. A strong correlation was found between the amount of fluid used and the weight gain in both the GFS and APS groups. But a strong correlation between duration of surgery and weight gain was found in the APS group only. The APS group also had a greater mean deltoid diameter increase (3.33 ± 1.56 cm vs. 2.1 ± 1.44 cm) and a higher postoperative first-hour visual analog pain scale score (5.81 ± 2 vs. 3.62 ± 1.6).

CONCLUSION

APS causes more fluid retention than GFS in shoulder arthroscopy when used for equal duration in similar procedures. Use of APS, prolongation of surgery, and increased amounts of irrigation fluid increase weight gain as a result of fluid retention.

Idiopathic Edema: A Case Report

Edema occurs when excess fluid is retained by interstitial tissue and is associated with several systemic conditions. The diagnosis of edema is generally made by physical and clinical assessment, and diuretics are the common treatment. Idiopathic edema predominantly affects women and occurs in patients who do not have any other pre-existing systemic problems. The etiology behind idiopathic edema has yet to be determined. We present a case of a 46-year-old woman diagnosed with idiopathic edema.

Tolvaptan alleviates excessive fluid retention of nephrotic diabetic renal failure unresponsive to furosemide

Patients with diabetic nephropathy develop nephrotic syndrome and may show limited response to conventional therapy. They often require earlier initiation of renal replacement therapy because they become refractory to diuretics, and experience excessive fluid retention. We aimed to investigate the efficacy of tolvaptan, an oral arginine vasopressin type 2 receptor antagonist, in a case series of 14 severe diabetic renal failure patients who were severely refractory to maximal doses of furosemide and had excessive fluid retention despite preserved cardiac function and residual renal function. All 14 patients experienced immediate and sustained water diuretic effects, resulting in alleviation of congestive heart failure. None required initiation of renal replacement therapy. Tolvaptan promptly increased urine volume and free water clearance, reversed progressive fluid retention, and alleviated congestive heart failure. Thus, tolvaptan could serve as a potential adjunct therapy for severe diabetic renal failure patients with excessive fluid retention and congestive heart failure.

Bioelectrical impedance analysis in the management of heart failure in adult patients with congenital heart disease

OBJECTIVE

The recognition of fluid retention is critical in treating heart failure (HF). Bioelectrical impedance analysis (BIA) is a well-known noninvasive method; however, data on its role in managing patients with congenital heart disease (CHD) are limited. Here, we aimed to clarify the correlation between BIA and HF severity as well as the prognostic value of BIA in adult patients with CHD.

DESIGN

This prospective single-center study included 170 patients with CHD admitted between 2013 and 2015. We evaluated BIA parameters (intra- and extracellular water, protein, and mineral levels, edema index [EI, extracellular water-to-total body water ratio]), laboratory values, and HF-related admission prevalence.

RESULTS

Patients with New York Heart Association (NYHA) functional classes III-IV had a higher EI than those with NYHA classes I-II (mean ± SD, 0.398 ± 0.011 vs 0.384 ± 0.017, P < .001). EI was significantly correlated with brain natriuretic peptide level (r = 0.51, P < .001). During the mean follow-up period of 7.1 months, Kaplan-Meier analysis showed that a discharge EI > 0.386, the median value in the present study, was significantly associated with a future increased risk of HF-related admission (HR = 4.15, 95% CI = 1.70－11.58, P < .001). A body weight reduction during hospitalization was also related to EI reduction.

CONCLUSIONS

EI determined using BIA could be a useful marker for HF severity that could predict future HF-related admissions in adult patients with CHD.

Pharmacokinetic and Pharmacodynamic Evaluation of Different PEGylated Human Interleukin-11 Preparations in Animal Models

Treating thrombocytopenia induced by chemotherapy remains an unmet-medical need. The use of recombinant human interleukin-11 (rhIL-11) requires repeated injections and induces significant fluid retention in some patients. Modification of human interleukin-11 with chemically inert polyethylene glycol polymer (PEG) may extend the peripheral circulation half-life leading to an improved pharmacokinetic and pharmadynamic profile. In this study, a number of rhIL-11 PEG conjugates were created to determine the optimal approach to prolong circulating half-life with the most robust pharmacological effect. The lead candidate was found to be a single 40-kDa Y-shaped PEG linked to the N-terminus, which produced a long-lasting circulating half-life, enhanced efficacy and alleviated side effect of dilutional anemia in healthy rat models. This candidate was also shown to be effective in myelosuppressive rats in preventing the occurrence of severe thrombocytopenia while ameliorating dilutional anemia, compared to rats receiving daily administration of unmodified rhIL-11 at the same dose. These data indicated that a single injection of the selected modified rhIL-11 for each cycle of chemotherapy regimen is potentially feasible. This approach may also be useful in treating patients of acute radiation syndrome when frequent administration is not feasible in a widespread event of a major radiation exposure.

Extracellular Fluid Excess Is Significantly Associated With Coronary Artery Calcification in Patients With Chronic Kidney Disease

BACKGROUND

Extracellular fluid (ECF) excess is an independent predictor of cardiovascular morbidity in patients undergoing dialysis. This study aimed to investigate the relationship between ECF status, which is affected by renal function, and coronary artery calcification (CAC), which is a marker of cardiovascular disease, in patients with chronic kidney disease (CKD).

METHODS AND RESULTS

A total of 1741 patients at all stages of pre-dialysis CKD from the prospective observational cohort of CMERC-HI (Cardiovascular and Metabolic Disease Etiology Research Center-High Risk) were analyzed for the association between ECF status and CAC. ECF status was defined as extracellular water-to-total body water ratio (ECW/TBW) measured using bioelectrical impedance analysis. ECF excess was defined as ECW/TBW ≥0.390 or ≥0.400 depending on its severity. To define CAC, Agatston coronary artery calcium scores were measured. A total coronary artery calcium score of ≥400 was defined as CAC. The CKD stages were defined according to estimated glomerular filtration rate calculated using the CKD Epidemiology Collaboration equation. ECW/TBW and the proportion of ECF excess increased with progressing CKD stages. Multivariable logistic regression analyses showed that ECW/TBW was independently associated with CAC (per 0.01 increase of ECW/TBW, odds ratio 1.168, 95% confidence interval, 1.079-1.264, P<0.001). The adjusted R2 for predicting higher coronary artery calcium scores and CAC significantly improved after ECW/TBW was added to conventional factors. This association was further confirmed by net reclassification and integrated discriminant improvements, sensitivity analysis, and subgroup analysis.

CONCLUSIONS

ECF status is independently associated with a high risk of CAC in patients with CKD.

STUDY REGISTRATION

URL: https://www.clinicaltrials.gov/. Unique identifier: NCT02003781.

Rapidly progressive dyspnea in gastrointestinal stromal tumor (GIST) with imatinib cardiac toxicity

Gastrointestinal stromal tumors (GISTs) are rare and current estimates range from 4,000 to 6,000 number of GIST cases in the USA annually. Imatinib, a tyrosine kinase inhibitor, has shown a survival benefit in GISTs, and the presence of KIT mutation status is predictive of response. The current case discusses rapidly progressive dyspnea and heart failure in an elderly male with metastatic GIST who was started on imatinib. Although reported as a rare and sporadic side effect of imatinib, the current case illustrates rapidity and the clinical significance of cardiotoxicity, with onset at 2 weeks.

Cases of imatinib-induced cardiotoxicity can range from being mild ventricular dysfunction to overt heart failure. Prior to starting imatinib, our patient had a history of hypertension. He subsequently ended up developing heart failure as acknowledged by the echocardiogram (ECHO). In general, elderly with preexisting cardiovascular comorbidity are at greater risk. The goal in such situations is immediate discontinuation or reduction of the imatinib dosage. The case prompts for awareness of imatinib cardiotoxicity. Moreover, a pretreatment cardiac assessment along with monitoring throughout therapy is therefore advisable. Also, imatinib-induced cardiotoxicity should be differentiated from imatinib-associated fluid retention, in which ECHO findings can be normal. This case report raises the concern for accelerated cardiotoxicity profile of imatinib. Further prospective studies with multidisciplinary input are needed to establish this association further.

Effects of whey protein in carbohydrate-electrolyte drinks on post-exercise rehydration

The purpose of this study was to examine the effects of different amounts of whey protein in carbohydrate-electrolyte (CE) drinks on post-exercise rehydration. Ten males completed 5 trials in a randomised cross-over design. A 4-h recovery was applied after a 60-min run at 65% VO_2peak in each trial. During recovery, the participants ingested a high-carbohydrate CE drink (CE-H), a low-carbohydrate CE drink (CE-L), a high-whey-protein (33 g·L^-1) CE drink (CW-H), a medium-whey-protein (22 g·L^-1) CE drink (CW-M) or a low-whey-protein (15 g·L^-1) CE drink (CW-L) in a volume equivalent to 150% of their body mass (BM) loss. The drinks were provided in six equal boluses and consumed by the participants within 150 min in each trial. After exercise, a BM loss of 2.15% ± 0.05% was achieved. Urine production was less in the CW-M and CW-H trials during recovery, which induced a greater fluid retention in the CW-M (51.0% ± 5.7%) and CW-H (55.4% ± 3.8%) trials than in any other trial (p < .05). The plasma albumin content was higher in the CW-H trial than in the CE-H and CE-L trials at 2 h (p < .05) and 3 h (p < .01) during recovery. The aldosterone concentration was lower in the CE-H trial than in the CW-M and CW-H trials after recovery (p < .05). It is concluded that the rehydration was improved when whey protein was co-ingested with CE drinks during a 4-h recovery after a 60-min run. However, this additive effect was only observed when whey protein concentration was at least 22 g·L^-1 in the current study.

A mixed methods study of symptom perception in patients with chronic heart failure

BACKGROUND

Early heart failure (HF) symptoms are frequently unrecognized for reasons that are unclear. We explored symptom perception in patients with chronic HF.

METHODS

We enrolled 36 HF out-patients into a longitudinal sequential explanatory mixed methods study. We used objectively measured thoracic fluid accumulation and daily reports of signs and symptoms to evaluate accuracy of detected changes in fluid retention. Patterns of symptom interpretation and response were explored in telephone interviews conducted every 2 weeks for 3-months.

RESULTS

In this sample, 44% had a mismatch between objective and subjective fluid retention; younger persons were more likely to have mismatch. In interviews, two patterns were identified: those able to interpret and respond appropriately to symptoms were higher in decision-making skill and the quality of social support received.

CONCLUSION

Many HF patients were poor at interpreting and managing their symptoms. These results suggest a subgroup of patients to target for intervention.

Impact of Isotonic Beverage on the Hydration Status of Healthy Chinese Adults in Air-Conditioned Environment

People living in tropical climates spend much of their time in confined air-conditioned spaces, performing normal daily activities. This study investigated the effect of distilled water (W) or isotonic beverage (IB) on the hydration status in subjects living under these conditions. In a randomized crossover design, forty-nine healthy male subjects either consumed beverage or IB over a period of 8 h (8 h) in a controlled air-conditioned environment. Blood, urine, and saliva samples were collected at baseline and after 8 h. Hydration status was assessed by body mass, urine output, blood and plasma volume, fluid retention, osmolality, electrolyte concentration and salivary flow rate. In the IB group, urine output (1862 ± 86 mL vs. 2104 ± 98 mL) was significantly lower and more fluids were retained (17% ± 3% vs. 7% ± 3%) as compared to W (p < 0.05) after 8 h. IB also resulted in body mass gain (0.14 ± 0.06 kg), while W led to body mass loss (-0.04 ± 0.05 kg) (p = 0.01). A significantly smaller drop in blood volume and lower free water clearance was observed in IB (-1.18% ± 0.43%; 0.55 ± 0.26 mL/min) compared to W (-2.11% ± 0.41%; 1.35 ± 0.24 mL/min) (p < 0.05). IB increased salivary flow rate (0.54 ± 0.05 g/min 0.62 ± 0.04 g/min). In indoor environments, performing routine activities and even without excessive sweating, isotonic beverages may be more effective at retaining fluids and maintaining hydration status by up to 10% compared to distilled water.

Renal water conservation determines the increase in body weight after surgery: A randomized, controlled trial

Background:

The present study was undertaken to identify factors that correlate with the gain in body weight after surgery.

Methods:

Twenty-one patients (median age of 49 years) were randomized to receive either Ringer × s acetate or 6% dextran 70 as their first infusion fluid during cholecystectomy or hysterectomy. Each patient's body weight was measured before the surgery and on the first postoperative morning. Blood and urine samples were analyzed for signs of stress, inflammation, and kidney injury. The fluid retention index (FRI), which reflects how strongly the kidneys excrete or retain fluid, was also calculated.

Results:

The body weight increased by a median of 0.4 kg in the crystalloid fluid group and by 1.0 kg in the colloid fluid group (maximum 2.5 kg, P < 0.01). This difference was due to less urinary excretion after surgery in the colloid group (P < 0.03). The increase in body weight did not correlate with the infused fluid volume, the plasma concentrations of C-reactive protein or cortisol, or the urinary excretion of albumin, cortisol, or neutrophil gelatinase-associated lipocalin. However, the body weight increased with the postoperative FRI score (r = 0.64; P < 0.003) and with the surgery-induced change in FRI score (r = 0.72; P < 0.002).

Conclusion:

How strongly the kidneys excrete or retain fluid, which can be assessed by urine sampling, was the strongest indicator of the increase in body weight during the day of surgery. The amount of fluid alone did not correlate with the gain in body weight.

Association of Calf Muscle Pump Stimulation With Sleep Quality in Adults

Prevention of lower extremity fluid pooling (LEFP) is associated with improved sleep quality. Physical activity and compression stockings are non-invasive methods used to manage LEFP, but both are associated with low adherence. Calf muscle pump (CMP) stimulation is an alternative and more convenient approach. Convenience sampling was used to recruit 11 participants between ages 45 and 65 with poor sleep quality. A within-person single-group pre-test-post-test design was used to evaluate changes in sleep quality, daytime sleepiness, and functional outcomes sensitive to impaired sleep as measured by the Pittsburgh Sleep Quality Index (PSQI), Functional Outcomes of Sleep Questionnaire, and Epworth Sleepiness Scale after 4 weeks of CMP stimulation. Statistical analysis included effect size (ES) calculations. After daily use of CMP stimulation, participants demonstrated improvement in overall sleep quality (ES = -.97) and a large reduction in daily disturbance from poor sleep (ES = -1.25). Moderate improvements were observed in daytime sleepiness (ES = -.53) and functional outcomes sensitive to sleepiness (ES = .49). Although causality could not be determined with this study design, these results support further research to determine whether CMP stimulation can improve sleep quality. © 2016 Wiley Periodicals, Inc.

Pretransplant Levels of CRP and Interleukin-6 Family Cytokines; Effects on Outcome after Allogeneic Stem Cell Transplantation

Several pretransplant factors, including CRP (C-reactive protein) levels, reflect the risk of complications after allogeneic stem cell transplantation. IL-6 induces CRP increase, and we therefore investigated the effects of pretransplant IL-6, soluble IL-6 receptors, IL-6 family cytokines and CRP serum levels on outcome for 100 consecutive allotransplant recipients. All patients had related donors, none had active infections and 99 patients were in complete remission before conditioning. The incidence of acute graft versus host disease (aGVHD) requiring treatment was 40%, survival at Day +100 82%, and overall survival 48%. Despite a significant correlation between pretransplant CRP and IL-6 levels, only CRP levels significantly influenced transplant-related mortality (TRM). However, CRP did not influence overall survival (OS). Pretransplant IL-31 influenced late TRM. Finally, there was a significant association between pretransplant IL-6 and early postconditioning weight gain (i.e., fluid retention), and this fluid retention was a risk factor for aGVHD, TRM and OS. To conclude, pretransplant CRP, IL-31 and early posttransplant fluid retention were independent risk factors for TRM and survival after allotransplantation.

Urinary Dopamine as a Potential Index of the Transport Activity of Multidrug and Toxin Extrusion in the Kidney

Dopamine is a cationic natriuretic catecholamine synthesized in proximal tubular cells (PTCs) of the kidney before secretion into the lumen, a key site of its action. However, the molecular mechanisms underlying dopamine secretion into the lumen remain unclear. Multidrug and toxin extrusion (MATE) is a H⁺/organic cation antiporter that is highly expressed in the brush border membrane of PTCs and mediates the efflux of organic cations, including metformin and cisplatin, from the epithelial cells into the urine. Therefore, we hypothesized that MATE mediates dopamine secretion, a cationic catecholamine, into the tubule lumen, thereby regulating natriuresis. Here, we show that [³H]dopamine uptake in human (h) MATE1-, hMATE-2K- and mouse (m) MATE-expressing cells exhibited saturable kinetics. Fluid retention and decreased urinary excretion of dopamine and Na⁺ were observed in Mate1-knockout mice compared to that in wild-type mice. Imatinib, a MATE inhibitor, inhibited [³H]dopamine uptake by hMATE1-, hMATE2-K- and mMATE1-expressing cells in a concentration-dependent manner. At clinically-relevant concentrations, imatinib inhibited [³H]dopamine uptake by hMATE1- and hMATE2-K-expressing cells. The urinary excretion of dopamine and Na⁺ decreased and fluid retention occurred in imatinib-treated mice. In conclusion, MATE transporters secrete renally-synthesized dopamine, and therefore, urinary dopamine has the potential to be an index of the MATE transporter activity.

Dipeptidyl Peptidase IV Inhibition Exerts Renoprotective Effects in Rats with Established Heart Failure

Circulating dipeptidyl peptidase IV (DPPIV) activity is associated with worse cardiovascular outcomes in humans and experimental heart failure (HF) models, suggesting that DPPIV may play a role in the pathophysiology of this syndrome. Renal dysfunction is one of the key features of HF, but it remains to be determined whether DPPIV inhibitors are capable of improving cardiorenal function after the onset of HF. Therefore, the present study aimed to test the hypothesis that DPPIV inhibition by vildagliptin improves renal water and salt handling and exerts anti-proteinuric effects in rats with established HF. To this end, male Wistar rats were subjected to left ventricle (LV) radiofrequency ablation or sham operation. Six weeks after surgery, radiofrequency-ablated rats who developed HF were randomly divided into two groups and treated for 4 weeks with vildagliptin (120 mg/kg/day) or vehicle by oral gavage. Echocardiography was performed before (pretreatment) and at the end of treatment (post-treatment) to evaluate cardiac function. The fractional area change (FAC) increased (34 ± 5 vs. 45 ± 3%, p < 0.05), and the isovolumic relaxation time decreased (33 ± 2 vs. 27 ± 1 ms; p < 0.05) in HF rats treated with vildagliptin (post-treatment vs. pretreatment). On the other hand, cardiac dysfunction deteriorated further in vehicle-treated HF rats. Renal function was impaired in vehicle-treated HF rats as evidenced by fluid retention, low glomerular filtration rate (GFR) and high levels of urinary protein excretion. Vildagliptin treatment restored urinary flow, GFR, urinary sodium and urinary protein excretion to sham levels. Restoration of renal function in HF rats by DPPIV inhibition was associated with increased active glucagon-like peptide-1 (GLP-1) serum concentration, reduced DPPIV activity and increased activity of protein kinase A in the renal cortex. Furthermore, the anti-proteinuric effect of vildagliptin treatment in rats with established HF was associated with upregulation of the apical proximal tubule endocytic receptor megalin and of the podocyte main slit diaphragm proteins nephrin and podocin. Collectively, these findings demonstrate that DPPIV inhibition exerts renoprotective effects and ameliorates cardiorenal function in rats with established HF. Long-term studies with DPPIV inhibitors are needed to ascertain whether these effects ultimately translate into improved clinical outcomes.

Dual Impact of Tolvaptan on Intracellular and Extracellular Water in Chronic Kidney Disease Patients with Fluid Retention

Objective Tolvaptan, an oral selective V2-receptor antagonist, is a water diuretic that ameliorates fluid retention with a lower risk of a worsening renal function than conventional loop diuretics. Although loop diuretics predominantly decrease extracellular water (ECW) compared with intracellular water (ICW), the effect of tolvaptan on fluid distribution remains unclear. We therefore examined how tolvaptan changes ICW and ECW in accordance with the renal function. Methods Six advanced chronic kidney disease patients (stage 4 or 5) with fluid retention were enrolled in this study. Tolvaptan (7.5 mg/day) added to conventional diuretic treatment was administered to remove fluid retention. The fluid volume was measured using a bioimpedance analysis device before (day 0) and after (day 5 or 6) tolvaptan treatment. Results Body weight decreased by 2.6%±1.3% (64.4±6.5 vs. 62.8±6.3 kg, p=0.06), and urine volume increased by 54.8%±23.9% (1,215±169 vs. 1,709±137 mL/day, p=0.03) between before and after tolvaptan treatment. Tolvaptan significantly decreased ICW (6.5%±1.5%, p=0.01) and ECW (7.5%±1.4%, p=0.02), which had similar reduction rates (p=0.32). The estimated glomerular filtration rate remained unchanged during the treatment (14.6±2.8 vs. 14.9±2.7 mL/min/1.73² m, p=0.35). Conclusion Tolvaptan ameliorates body fluid retention, and induces an equivalent reduction rate of ICW and ECW without a worsening renal function. Tolvaptan is a novel water diuretic that has a different effect on fluid distribution compared with conventional loop diuretics.

Plasma pro-endothelin-1 peptide concentrations rise in chronic kidney disease and following selective endothelin A receptor antagonism

Background

Endothelin 1 (ET‐1) contributes to chronic kidney disease (CKD) development and progression, and endothelin receptor antagonists are being investigated as a novel therapy for CKD. The proET‐1 peptides, endothelin‐like domain peptide (ELDP) and C‐terminal pro‐ET‐1 (CT‐proET‐1), are both potential biomarkers of CKD and response to therapy with endothelin antagonists.

Methods and Results

We assessed plasma and urine ELDP and plasma CT‐proET‐1 in CKD patients with minimal comorbidity. Next, in a randomized double‐blind crossover study of 27 subjects with proteinuric CKD, we examined the effects of 6 weeks of treatment with placebo, sitaxentan (endothelin A antagonist), and nifedipine on these peptides alongside the primary end points of proteinuria, blood pressure, and arterial stiffness. Plasma ELDP and CT‐proET‐1 increased with CKD stage (both P<0.0001), correlating inversely with estimated glomerular filtration rate (both P<0.0001). Following intervention, placebo and nifedipine did not affect plasma and urine ELDP or plasma CT‐proET‐1. Sitaxentan increased both plasma ELDP and CT‐proET‐1 (baseline versus week 6±SEM: ELDP, 11.8±0.5 versus 13.4±0.6 fmol/mL; CT‐proET‐1, 20.5±1.2 versus 23.3±1.5 fmol/mL; both P<0.0001). Plasma ET‐1 was unaffected by any treatment. Following sitaxentan, plasma ELDP and CT‐proET‐1 correlated negatively with 24‐hour urinary sodium excretion.

Conclusions

ELDP and CT‐proET‐1 increase in CKD and thus are potentially useful biomarkers of renal injury. Increases in response to endothelin A antagonism may reflect EDN1 upregulation, which may partly explain fluid retention with these agents.

Clinical Trial Registration

URL: www.clinicalTrials.gov Unique identifier: NCT00810732

Intrarenal bradykinin elicits reno-renal reflex sympatho-excitation and renal nerve-dependent fluid retention

AIMS

The renal sensory nerves are importantly involved in the sympathetic regulation of cardiovascular and renal function. Two reno-renal reflexes are recognized, one in which activation of renal sensory nerves elicits a renal sympatho-inhibition, and one which causes a renal sympatho-excitation and about which little is known. This study investigated the role of bradykinin (BK) in engaging an excitatory reno-renal reflex.

METHODS

Rats were anaesthetized (chloralose/urethane) and prepared for the measurement of renal function or renal sympathetic nerve activity (RSNA). BK was infused into the cortico-medullary border of the ipsilateral kidney and the impact on contralateral renal function and RSNA evaluated.

RESULTS

Intrarenal infusion of BK at 3 × 10(-9) and 6 × 10(-9) g L(-1) had no effect on mean arterial pressure, at 104 ± 5 mmHg or glomerular filtration rate in either the ipsilateral or contralateral kidneys, at 4.31 ± 0.45 mL min(-1) kg(-1) . At the highest dose of BK, fractional sodium excretion (FENa) was 1.47% in the ipsilateral kidney and was significantly lower, at 0.64% (P < 0.05) in the contralateral kidney but this difference did not occur following ipsilateral renal denervation. Ipsilateral intrarenal infusion of BK at 3 × 10(-9) , 6 × 10(-9) and 1.2 × 10(-8) g L(-1) elicited dose-related increases (P < 0.05) in contralateral RSNA, reaching some 78% at the highest dose, but these responses were prevented by ipsilateral renal denervation.

CONCLUSIONS

Intrarenal infusion of BK produced an excitatory reno-renal reflex which was expressed as a renal nerve-dependent antinatriuresis in the contralateral kidney. The findings suggest that inflammatory mediators such as BK may be important in initiating a sympatho-excitation associated with renal and cardiovascular diseases.

An amino acid-electrolyte beverage may increase cellular rehydration relative to carbohydrate-electrolyte and flavored water beverages

BACKGROUND

In cases of dehydration exceeding a 2% loss of body weight, athletic performance can be significantly compromised. Carbohydrate and/or electrolyte containing beverages have been effective for rehydration and recovery of performance, yet amino acid containing beverages remain unexamined. Therefore, the purpose of this study is to compare the rehydration capabilities of an electrolyte-carbohydrate (EC), electrolyte-branched chain amino acid (EA), and flavored water (FW) beverages.

METHODS

Twenty men (n = 10; 26.7 ± 4.8 years; 174.3 ± 6.4 cm; 74.2 ± 10.9 kg) and women (n = 10; 27.1 ± 4.7 years; 175.3 ± 7.9 cm; 71.0 ± 6.5 kg) participated in this crossover study. For each trial, subjects were dehydrated, provided one of three random beverages, and monitored for the following three hours. Measurements were collected prior to and immediately after dehydration and 4 hours after dehydration (3 hours after rehydration) (AE = -2.5 ± 0.55%; CE = -2.2 ± 0.43%; FW = -2.5 ± 0.62%). Measurements collected at each time point were urine volume, urine specific gravity, drink volume, and fluid retention.

RESULTS

No significant differences (p > 0.05) existed between beverages for urine volume, drink volume, or fluid retention for any time-point. Treatment x time interactions existed for urine specific gravity (USG) (p < 0.05). Post hoc analysis revealed differences occurred between the FW and EA beverages (p = 0.003) and between the EC and EA beverages (p = 0.007) at 4 hours after rehydration. Wherein, EA USG returned to baseline at 4 hours post-dehydration (mean difference from pre to 4 hours post-dehydration = -0.0002; p > 0.05) while both EC (-0.0067) and FW (-0.0051) continued to produce dilute urine and failed to return to baseline at the same time-point (p < 0.05).

CONCLUSION

Because no differences existed for fluid retention, urine or drink volume at any time point, yet USG returned to baseline during the EA trial, an EA supplement may enhance cellular rehydration rate compared to an EC or FW beverage in healthy men and women after acute dehydration of around 2% body mass loss.

Antidiuretic effects of the endothelin receptor antagonist avosentan

Several clinical studies have investigated the potential benefits of endothelin receptor antagonism in chronic pathologies such as diabetic kidney disease. However, fluid retention and edema have been identified as major side effects of endothelin receptor antagonists. In the present study we hypothesized that avosentan which was described as a predominant ET_A receptor antagonist would produce fluid retention at high concentrations where non-specific blockade of ET_B receptors may occur. Incremental doses of the predominant ET_A receptor antagonist SPP301 (0.003; 0.03; 3 mg/kg) were administered intravenously to anesthetized Sprague-Dawley rats undergoing saline diuresis. Diuresis, glomerular filtration rate, and blood pressure (BP) were monitored. SPP301 decreased urine output (5.6; 34.8; 58.8% decrease from vehicle) and fractional excretion of water (5.7; 31.7; 56.4% decrease from vehicle) in a concentration-dependent manner. Glomerular filtration rate was unchanged while BP was reduced by 10 mmHg only by the highest dose of SPP301. Administration of the ET_B selective receptor antagonist BQ-788 (3 mg/kg) following SPP301 3 mg/kg did not further decrease urine output or water excretion and was without effect on glomerular filtration rate. These data indicate that increasing concentrations of SPP301 may also block ET_B receptors and cause antidiuresis. This effect could explain why fluid retention and edema occur during treatment with predominant ET_A receptor blockers.

The pathophysiological mechanism of fluid retention in advanced cancer patients treated with docetaxel, but not receiving corticosteroid comedication

AIMS

Fluid retention is a phenomenon associated with taxoids. The principal objective of this study was to investigate the pathophysiological mechanism of docetaxel-induced fluid retention in advanced cancer patients.

METHODS

Docetaxel was administered as a 1 h intravenous infusion every 3 weeks, for at least 4-6 consecutive cycles, to patients with advanced breast (n = 21) or ovarian (n = 3) carcinoma, who had received previous chemotherapy, 21 for advanced disease. Phase II clinical trials have shown that 5 day corticosteroid comedication, starting 1 day before docetaxel infusion, significantly reduces the incidence and severity of fluid retention. This prophylactic corticosteroid regimen is currently recommended for patients receiving docetaxel but was not permitted in this study because of its possible interference with the underlying pathophysiology of the fluid retention.

RESULTS

Fluid retention occurred in 21 of the 24 patients but was mainly mild to moderate, with only five patients experiencing severe fluid retention. Eighteen patients received symptomatic flavonoid treatment, commonly prescribed after the last cycle. Specific investigations for fluid retention confirmed a relationship between cumulative docetaxel dose and development of fluid retention. Capillary filtration test analysis showed a two-step process for fluid retention generation, with progressive congestion of the interstitial space by proteins and water starting between the second and the fourth cycle, followed by insufficient lymphatic drainage.

CONCLUSIONS

A vascular protector such as micronized diosmine hesperidine with recommended corticosteroid premedication and benzopyrones may be useful in preventing and treating docetaxel-induced fluid retention.