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Early diagnosis of acute kidney injury (AKI) and preventive measures can likely decrease the severity of the injury and improve patient outcomes. Current hemodynamic monitoring variables, including blood pressure, heart and respiratory rates, temperature, and oxygenation status, have been used to identify patients at high risk for AKI. Despite the widespread use of such variables, their ability to accurately and timely detect high-risk patients has been questioned. Therefore, there is a critical need to develop and validate tools that can measure new and more kidney-specific hemodynamic and laboratory variables, potentially assisting with AKI risk stratification, implementing appropriate and timely preventive measures, and hopefully improved outcomes. The new ultrasonography techniques provide novel insights into kidney hemodynamics and potential management and/or therapeutic targets. Contrast-enhanced ultrasonography, Doppler flow patterns of hepatic veins (HV), portal vein (PV), and intra- kidney veins (iKV), and ultrasound elastography are among approaches that may provide such information, particularly related to vascular changes in acute kidney injury, venous volume excess or congestion, and fluid tolerance. This review summarizes the current state of these techniques and their relevance to kidney hemodynamic management.

Background: The association between ultrafiltration rate (UFR) and mortality may be affected by the muscle mass or volume status in hemodialysis (HD) patients. However, there is an absence of data regarding this association. Methods: We performed an observational study on patients (≥18 years old) who had been on HD for at least 3 months. A body composition monitor (BCM) was used for baseline bioimpedance analysis measurement. The primary composite outcome was defined as the time to death or the first cardiovascular event. Results: The median (interquartile range) UFR, volume excess measured by the BCM, and lean tissue index (LTI) (calculated as lean tissue mass/height2) were 11.4 (8.0–15.0) mL/h/kg, 2.4 (1.4–4.1) L, and 12.5 (10.4–14.4) kg/m2, respectively. During 284 person-years of follow-up, the primary outcome occurred in 44 of the 167 patients (26%). Higher UFR was associated with an increased outcome of death or cardiovascular event; the adjusted hazard ratio (HR) was 1.044 (95% confidence interval [CI]: 1.006–1.083). This association remained consistent even after adjusting for volume excess. However, the association between UFR and the primary outcome was modified by LTI (pinteraction = 0.027); the association was significant in patients with LTI < 12.5 kg/m2, and the HR (95% CI) was 1.050 (1.001–1.102). Conclusion: Higher UFR was associated with an increased risk of a composite outcome of death or cardiovascular event regardless of volume status in HD patients. However, muscle mass may modify the association between higher UFR and increased risk of a composite outcome.

INTRODUCTION The non-invasive analysis of body fluid composition with bio-electrical impedance analysis (BIA) provides additional information allowing for more persona-lised therapy to improve outcomes. The aim of this study is to assess the prognostic value of fluid overload (FO) in the first week of intensive care unit (ICU) stay. MATERIAL AND METHODS A retrospective, observational analysis of 101 ICU patients. Whole-body BIA measurements were performed, and FO was defined as a 5% increase in volume excess from baseline body weight. RESULTS Baseline demographic data, including severity scores, were similar in both the fluid overload-positive (FO+, n = 49) patients and in patients without fluid overload (FO-, n = 52). Patients with FO+ had significantly higher cumulative fluid balance during their ICU stay compared to those without FO (8.8 ± 7.0 vs. 5.5 ± 5.4 litres; P = 0.009), VE (9.9 ± 6.5 vs. 1.5 ± 1.5 litres; P < 0.001), total body water (63.0 ± 9.5 vs. 52.8 ± 8.1%; P < 0.001), and extracellular water (27.0 ± 7.3 vs. 19.6 ± 3.7 litres; P < 0.001). The presence of 5%, 7.5%, and 10% fluid overload was directly associated with increased ICU mortality rates. The percentage fluid overload (P = 0.039) was an independent predictor for hospital mortality. CONCLUSIONS A higher mortality rate in ICU-patients with FO was observed. FO is an independent prognostic factor because neither APACHE-II, SOFA, nor SAPS-II significantly differed on admission between survivors and non-survivors. Further research is needed to confirm these data prospectively and to evaluate whether BIA-guided deresuscitation in the subacute phase will improve mortality rates.

Objective To evaluate outcomes in patients with gynaecological cancer related lymphoedema treated with liposuction. Methods A prospective analysis of 21 patients who underwent liposuction followed by compression therapy for chronic unilateral lower limb lymphoedema with up to 8 years follow up was performed. Results Duration of lymphoedema prior to liposuction ranged from 4 to 28 years (mean 15.2 years). The mean age at time of liposuction was 52 years (range 37–67). Estimated volume excess in the affected limb ranged from 1.6 to 12 l (mean 4.7 l). The mean percentage reduction was 92.6% at 6 months (range 59.4–159.9) and 88.9% (range 60.9–127.5) at 1 year. Longer term follow-up of 6 patients at 5 years post-liposuction revealed a mean percentage reduction of 113.6% (range 83.5–155.5). Conclusion Our experience of liposuction combined with compression garments has demonstrated significant and sustainable reduction in limb volume in patients with lower limb lymphoedema secondary to gynaecological malignancy.

Background Lymphedema leads to early deposition of adipose tissue. This may explain why conservative therapies such as complex decongestive therapy (CDT) and controlled compression therapy (CCT), as well as various forms of microsurgical reconstructions, cannot completely remove the excess volume in patients with a large chronic nonpitting lymphedema. Liposuction is therefore a logical and tempting treatment to reduce the adipose tissue volume excess. This article outlines the benefits of using liposuction and presents evidence to support its use. Methods The mechanism between adipose tissue depositions is described as well as the surgical technique, postoperative care, volume measurements, effects on the lymph transport, and follow-up. Results Fifteen years' follow-up shows complete reduction of the excess volume without recurrence following liposuction in patients with postmastectomy arm lymphedema. The same promising results can also be seen in patients with leg lymphedema. Conclusion Various types of treatment of lymphedema are under discussion and there has been some controversy regarding liposuction for lymphedema. Improvements in techniques, patient preparation, and patient follow-up have led to a greater and wider acceptance of liposuction as a treatment for lymphedema in patients with large chronic nonpitting extremity lymphedemas.

Several different approaches for reconstruction have been already described taking into account size and shape of the native breast, location and type of cancer, whether adjuvant radiation and/or chemotherapy is needed, patient’s demographic information, and surgeon’s preferences and experience. We report a case of reconstruction in burn patient using a breast sensitive perforator flap from the contralateral side. Thanks to the volume excess, the left side was large enough to reconstruct the affected side. A supero-medial pedicled reduction mammaplasty was performed on the left breast, and the excess inferior-part was elevated laterally and caudally off the pectoralis major. The flap was supplied by two perforators from the internal mammary vessels, and it was transposed to the right side after resection of the burned breast tissue. The right nipple-areola complex was left buried under the flap. After 2 months, the flap pedicle was deepithelialized, debulked, and passed through inframammary fold. The nipple-areola complex was released as a pedicled flap and sutured to the flap tissue approximately at the same level of the contralateral from the sternal notch. Preoperative sensitivity assessment demonstrated worst sensation of the right breast compared to the uninjured side. At 6 months, postoperatively, the patient could localize pressure and sensibility tested by the use of cotton wool and a pinprick test was quite normal. A clear improvement was observed in cutaneous pressure sensation thresholds over the time. At 12 months, she could recognize cotton wool and a pinprick. No changes were observed in the nipple-areola complex sensibility. Level of Evidence: Level V, therapeutic study.

The measurement and management of volume state among long-term dialysis patients has not received much attention. Recent reports suggest that relative plasma volume monitoring may be useful in identifying patients who have volume excess. Among patients who have evidence of excess volume by relative plasma volume monitoring, excess volume removal leads to improvement in interdialytic ambulatory blood pressure. Implementation of this technique can result in improved classification of patients into volume-sensitive and -resistant categories and therefore improve the management of hypertension.

Volume management is an integral component of the care of patients with acute kidney injury (AKI). Considerable controversy exists regarding the use of pharmacological agents for volume management. Although overt fluid overload is often seen in AKI and may prompt attention for the use of diuretics, often these agents are used in the absence of fluid retention. Over the last decade several new agents have become available for volume removal. We reviewed the literature on this topic and addressed four key questions for the appropriate utilization of these agents. These include the drug targets and mechanism of action of available agents; clinical goals and criteria for timing of intervention; adaptation of therapy for specific clinical settings and measures required for monitoring effectiveness and patient safety. This report details our current knowledge in this area, provides evidence-based clinical practice recommendations where appropriate, and formulates a research agenda to address unanswered questions. (Int J Artif Organs 2008; 31: 127–44)

Volume expansion 1,2 is frequent among hypertensives.3 Impedance Cardiography (ICG) measures hemodynamic disturbances,3,4 and apparently estimates volume excess 5 through the thoracic fluid content (TFC), an inverse of thoracic impedance(Z0). This article is protected by copyright. All rights reserved.

Fluid removal via ultrafiltration is a primary function of hemodialysis, and inadequate volume control is associated with significant morbidity and mortality among chronic dialysis patients. Treatment-to-treatment fluid removal goals are typically calculated on the basis of interdialytic weight gain and prescribed target weight. The clinical effect of frequent missed target weights is unclear. This study was designed to evaluate the associations of postdialysis weights above and below the prescribed target weight (separately) and outcomes.Data were taken from a national cohort of 10,785 prevalent, thrice-weekly, in-center hemodialysis patients dialyzing from 2005 to 2008 (median time at risk, 2.1 [25th percentile, 75th percentile] years) at a single dialysis organization. Patients were characterized as having an above target weight miss if their postdialysis weight was2 kg above target weight in at least 30% of baseline treatments (14.6% of cohort), or they were characterized as control otherwise. Below target weight miss characterization was analogous for patients with postdialysis weight2 kg below target weight (6.6% of cohort). Coprimary endpoints were all-cause and cardiovascular mortality.Above target weight miss in at least 30% of treatments (versus not) was associated with greater all-cause mortality (adjusted hazard ratio, 1.28; 95% confidence interval, 1.15 to 1.43); and below target weight miss in at least 30% of treatments (versus not) was associated with greater all-cause mortality (adjusted hazard ratio, 1.22; 95% confidence interval, 1.05 to 1.40). Both above and below target weight misses were also significantly associated with greater cardiovascular mortality. Secondary analyses demonstrated dose-response relationships between target weight misses and mortality. Results from sensitivity analyses considering the difference in postdialysis and target weights as a proportion of body weight were analogous to the primary results.Postdialysis weights2 kg above and below target weight are associated with higher all-cause and cardiovascular mortality. Consistent target weight achievement is a viable target for improving fluid management.

The aim of this study was to objectively measure impairment of arm function in women with breast cancer-related lymphoedema (BCRL), and investigate possible associations between this, arm volume excess, and psychological morbidity as measured by the Medical Outcomes Study 36-item short form (SF-36) questionnaire. A total of 48 patients were recruited. Manual dexterity was significantly impaired in the affected arm, independent of dominant or non-dominant arm involvement, but was not associated with arm volume excess. Psychological morbidity was significantly impaired in the domains of ‘physical function’ and ‘bodily pain’ when compared with population controls. Degree of impairment in the ‘physical function’ domain correlated with the absolute level of objectively tested manual dexterity. Impairment of manual dexterity appears to have a greater impact than arm volume excess on the overall psychological morbidity associated with BCRL, suggesting that greater emphasis should be placed upon arm function in the assessment, treatment targeting, and monitoring of patients with this condition.

Estimates of body water, fat-free mass, and body fat in patients on peritoneal dialysis by anthropometric formulas. Background Anthropometric formulas that are used to estimate body water in peritoneal dialysis patients can also be used to estimate fat-free mass and body fat. Evaluation of body composition by the anthropometric formulas rests on two assumptions: ( 1 ) fat contains no water, and ( 2 ) the water content of the fat-free mass is constant (72%). Methods We compared estimates of body water, fat-free mass, and body fat by anthropometric formulas to estimates employing dilution of tracer substances to measure body water and standard methods to analyze body composition in studies performed on peritoneal dialysis patients. We also analyzed the potential errors of the estimates of body composition by the formulas. Results Estimates of the average body composition provided by the anthropometric formulas agreed with estimates provided by the standard methods. However, these formulas have the potential of introducing large errors when estimating body composition in individuals differing from the average subject, either because the anthropometric formulas do not account for major determinants of body composition, such as physical exercise, nutrition, and catabolic illness, or because these formulas systematically overestimate body water in subjects who are obese or experiencing volume excess. Conclusion Anthropometric formulas currently in existence can provide only approximations of body composition and may be the sources of large errors in evaluating body composition in peritoneal dialysis patients. The potential errors include estimates of body water. These errors may alter the interpretation of urea kinetic studies in certain categories of peritoneal dialysis patients (e.g., obese subjects).

Congenital breast malformations have an incidence between 2 and 6 % with its range in severity from the relatively minor to major chest wall deformities. Throughout the breast’s development and evolution, alterations often appear due to volume excess (hypertrophies) or absence of volume (atrophy, hypotrophy), unequal development (asymmetries), or malformations (tuberous breasts).

This article discusses a technique of cervicofacial rejuvenation that involves ultrasound-assisted lipectomy. This method is indicated for those patients who might be early candidates for a rhytidectomy, and/or those with an adipose volume excess in the lower facial and cervical areas. The application of ultrasonic energy stimulates skin retraction and allows for the superficial fat to be more safely accessed than can be accomplished with conventional liposuction methods. This technique, along with a retrospective analysis of the first 26 cases treated with the technique, will be presented in this article.

We designed one-and-a-half-barrel vascularized free fibular flap which is a further modification of the double-barrel technique, and we tried to overcome the discrepancy between mandible and fibula flap. We used this flap in case of a segmental mandibular defect that occurred as a result of a giant cell reparative granuloma excision. This new modification eliminated volume insufficiency of the classical technique and volume excess of the double-barrel technique.A segmental mandibular defect that occurred as a result of giant cell reparative granuloma excision was reconstructed using one-and-a-half-barrel vascularized free fibular flap. The size discrepancy between mandible and free fibula flap is a well-known problem, and this new modification of free fibular flap eliminated volume insufficiency or excess problems of the other techniques.

BACKGROUND The main objective of this study was to theoretically quantify the fluctuations of fluid volume excess for different modes of intermittent ultrafiltration schedules and to compare the prediction for the typical and asymmetric thrice-weekly schedule to clinical, physiological and biophysical markers of volume expansion in a group of stable haemodialysis patients. METHODS Overall volume excess (V(OVE)) was described as the sum of a time-independent (V(0)) and a time-dependent component (V). An exact relationship was developed to relate V to variable treatment frequency, treatment spacing and net volume accumulation rate. In a single-centre haemodialysis population, body mass profiling was combined with volume state evaluation by bioimpedance analysis, N-terminal pro-B-type natriuretic peptide (NT-pro BNP) levels, clinical signs, a volume questionnaire and blood pressure levels. RESULTS In 23 patients following the typical thrice-weekly schedule, the time-averaged volume excess (V) during the whole week (1.1 ± 0.5 L) was significantly larger than that during the midweek interval (0.9 ± 0.4 L) (P < 0.002) by a factor comparable to that of 1.21 obtained from the theoretical analysis. V(OVE) was 1.3 ± 1.7 L and significantly related to pre- (P < 0.001) and post-dialysis levels of NT-pro BNP (P < 0.001). CONCLUSION Asymmetric treatment spacing such as with the typical thrice-weekly treatment schedule leads to a significant increase in time-averaged volume excess. The theoretical analysis allows for comparison of time-averaged volume excess in treatments varying with regard to treatment frequency and regularity and could be helpful to prescribe post-treatment volume (target weight) for such variable treatment modes.

Background: The epidemiology of hypertension among hemodialysis (HD) patients is difficult to describe accurately because of difficulties in the assessment of blood pressure (BP). Methods: Using 44-hour interdialytic ambulatory BP measurements, we describe the epidemiology of hypertension in a cohort of 369 patients. To seek correlates of hypertension control, antihypertensive agents were withdrawn among patients with controlled hypertension and ambulatory BP monitoring was repeated. Results: Hypertension (defined as an average ambulatory systolic BP ≧135 mm Hg or diastolic BP ≧85 mm Hg, or the use of antihypertensive medications) was prevalent in 82% of the patients and independently associated with epoetin use, lower body mass index and fewer years on dialysis. Although 89% of the patients were being treated, hypertension was controlled adequately in only 38%. Poor control was independently associated with greater antihypertensive drug use. Inferior vena cava (IVC) diameter in expiration was associated with increased risk of poorly controlled hypertension both in cross-sectional analysis and after withdrawal of antihypertensive drugs. Conclusions: Interdialytic hypertension is highly prevalent and difficult to control among HD patients. End-expiration IVC diameter is associated with poor control of hypertension in cross-sectional analyses as well as after washout of antihypertensive drugs. Among HD patients, an attractive target for improving hypertension control appears to be the reduction of extracellular fluid volume.

Background: Secondary unilateral lymphedema in the leg may occur as a consequence of pelvic surgery and/or radiation therapy, which causes damage to the pelvic lymphatic system. To date, assessment has been typically by manual measurement of the volume excess of the affected leg compared to the contralateral leg. In contrast, the assessment of unilateral arm lymphedema is readily accomplished by the use of bioelectrical impedance spectroscopy (BIS) as an increased inter-arm impedance ratio due to the presence of excess lymph in the affected arm relative to that of the unaffected arm. The presence of lymphedema is defined by a value of this ratio greater than the mean ratio plus three standard deviations (SD) observed in a comparable healthy population. The aim of the present study was to determine the equivalent reference range of the impedance ratio for the legs. This would allow a cut-off value to be established as a criterion for the detection and assessment of lower limb lymphedema. Methods: The impedances of the legs of 172 healthy females and 150 healthy males, measured by BIS, were extracted from an accumulated database of impedance data. These data were used to determine the normal distribution of inter-leg impedance ratios and the reference range and threshold value (mean + 3 SD). Results: The presence of lymphedema is indicated when the impedance ratio exceeds 1.167 in males and 1.136 in females. Unlike in the arms, the effect of limb dominance in the legs is minimal and it is suggested that no correction for limb dominance is warranted. Conclusions: The impedance ratio thresholds for lymphedema of the legs have been established, opening the way for BIS to become established clinically for the early detection and assessment of lower limb lymphedema.

Presentamos una combinación de procedimientos quirúrgicos para el tratamiento del exceso de volumen abdominal con flacidez moderada, utilizando una miniabdominoplastia con despegamiento y desinserción umbilical, asociada a liposucción. La indicación de la técnica se restringe a aquellos casos en los que la liposucción aislada provocaría un agravamiento de la flacidez, mientras que una abdominoplastia clásica implicaría una resección exagerada de piel o la necesidad de dejar una pequeña cicatriz vertical. Una miniabdominplastia trataría solamente la flacidez del abdomen inferior, dejando un exceso de piel en la región supraumbilical. La combinación de liposucción amplia y despegamiento controlado del área central del abdomen, asociada a una desinserción umbilical y su posterior reinserción unos 2 a 4 cm más abajo, nos permite lograr una completa plicatura de los rectos abdominales, con una buena resección del exceso cutáneo del abdomen inferior, además de un tratamiento adecuado de la flacidez moderada del abdomen superior.

Coronary artery disease is traditionally considered the main predictor of mortality in end stage renal disease (ESRD) patients. Clinical symptoms of heart failure (HF) in these patients are often under-appreciated because of poor baseline activity level. More over, ESRD patients are vulnerable to

Background One of the option for reconstruction of segmental mandibular defect is the vascularized free fibular flap. However, difference in height between mandible and fibula causes aesthetic and functional problems. But lack of a flap wide enough to completely fill the mandibular defect is an important disadvantage for us(1). The double barrel fibula flap has been useed to eliminate this disadvantage, but this flap is too large(2-4). A piece of non-vascularized residual fibula have used as graft in addition to vascularized fibula flap(5). We designed one and a half barrel vascularized free fibular flap to overcome the disadvantages of both techniques. Methods Eight centimeter length mandibular body segment was excised because of giant cell reparative granuloma diagnosis. Vascularized fibular flap was harvested and shaped as follows. A small piece of bone (segment B) was removed at the middle of the flap to fold the flap (Figure 1). The distal half of the flap had been splitted longitidunally, and the bone segment away from the perforator vessels (segment D) were removed. And then two remaining fibula segments were folded, and placed in parallel to each other in the defect (Figure 2). Results The flap has survived. Radiography revealed bone healing between the fibula and mandible. Conclusions One and a half barrel technique may be a good solution for incompatibility of the sizes of the segmental mandibular defect and the vascularized fibula flap. This technique eliminates volume insufficiency of the classical technique, and volume excess of the double-barrel technique. One and a half vascularized fbula flap perfect fit for mandibular defect. Figure 1. Schematic drawing of the flap (arrow is showing the direction of the folding) Figure 2. The final view of the flap in the defect. References 1. Chang YM, Tsai CY, Wei FC. One-stage, double-barrel fibula osteoseptocutaneous flap and immediate dental implants for functional and aesthetic reconstruction of segmental mandibular defects. Plast Reconstr Surg. 2008;122(1):143-5. 2. Jones NF, Swartz WM, Mears DC, Jupiter JB, Grossman A. The "double barrel" free vascularized fibular bone graft. Plast Reconstr Surg. 1988;81(3):378-85. 3. Horiuchi K, Hattori A, Inada I, et al. Mandibular reconstruction using the double barrel fibular graft. Microsurgery. 1995;16(7):450-4. 4. Bahr W, Stoll P, Wachter R. Use of the "double barrel" free vascularized fibula in mandibular reconstruction. J Oral Maxillofac Surg. 1998;56(1):38-44. 5. Lee JH, Kim MJ, Choi WS, et al. Concomitant reconstruction of mandibular basal and alveolar bone with a free fibular flap. Int J Oral Maxillofac Surg. 2004;33(2):150-6. Disclosure/Financial Support None of the authors has a financial interest in any of the products.

Background Plasma volume (PV) expansion is a hallmark feature of worsening heart failure that is notoriously underestimated by clinical examination. While radioisotope assays optimally quantify PV status, numerous haemodialysis-based equations also exist for its estimation. The prognostic utility of such formulas in chronic heart failure (CHF) is unknown. Methods We analysed the relation between estimated PV status and mortality in 246 outpatients with CHF (mean (±SD) age 67±13 years, NYHA class 2±1, LVEF 28±8%). PV status was calculated (Hakim RM, et al) by subtracting the patients actual PV ((1-haematocrit) × (a + (b × weight)); a and b are gender-specific constants) from their ideal PV ((c × weight); c=gender-specific constant). Results Median (±IQR) PV status was—261±550 ml with 78% and 21% of patients having PV contraction and expansion, respectively. Patients with PV excess had significantly higher creatinine and lower albumin levels. Over a median follow-up of 13±16 months, 36 (15%) patients died. PV status predicted mortality (HR 1.001, 95% CI 1.001 to 1.002, p=0.001) in a graded fashion (Abstract 104 figure 1A) and did so independently of NYHA class, LVEF, weight, haematocrit and creatinine. A PV status ≤−178 ml optimally predicted survival (ROC AUC 0.68, p=0.0007) and conferred a 75% reduced hazard for death (HR 0.16, 95% CI 0.07 to 0.37, p Conclusions Calculating plasma volume status in CHF patients appears prognostically useful and suggests that dehydration is better tolerated than volume excess in these individuals and that targeting therapy to achieve a plasma volume status ≤178 ml might increment survival.

In six inbred dogs with neonatally-induced coarctation hypertension, and in seven littermate controls, acute responses of proximal arterial pressure and plasma renin activity (PRA) to converting enzyme inhibitor (CEI; SQ 20,881, 0.5 mg/kg i.v.) were serially examined. Studies were performed at 2, 6, and 12 months post-aortic banding under sodium-replete and -deplete conditions. Both in normotensive controls and in coarcted dogs, depressor responses (pre- minus post-CEI values) were positively correlated, not only with initial (pre-CEI) PRA, but also independently with initial blood pressure. Although absolute depressor responses in coarcted dogs exceeded those of the control group, there were no significant group differences when, by analysis of covariance, depressor responses were adjusted for the physiologic influence of initial pressure. Similarly, depressor responses expressed as a percent of initial pressure were comparable in coarcted and control groups. Initial PRA and PRA response to CEI in coarcted dogs were also comparable to control dogs; the PRA response correlated with initial PRA in both groups. CEI did not significantly diminish the magnitude of blood-pressure difference between coarcted and control dogs. Thus, in neonatally-induced coarctation hypertension, under both sodium replete- and -deplete conditions: 1) acute depressor and PRA responses to CEI are modulated by the same factors that influence responses of normotensive controls; 2) larger absolute depressor responses to CEI appear to be a physiologic function of higher initial pressure; and 3) blood pressure excess over littermate controls is largely sustained by CEI-resistant factors, potentially including the known volume excess in coarcted dogs.

Dialysis time is increasingly being appreciated as an important measure of dialysis adequacy. Increased dialysis time leads to better control of volume excess, to reduced occurrence of intradialytic hypotension, and to better control of serum phosphorus. Nevertheless, the amount of benefit obtainable by moderate increases in dialysis time in patients following a three-times-per-week schedule has not been well established, and the analysis is confounded by associations between prescribed and/or delivered dialysis time and factors related to patient mortality.

BACKGROUND In patients with chronic heart failure (CHF), volume overload is usually described as an expansion of plasma volume (PV). Additional red cell volume (RCV) expansion also occurs in a relevant fraction of compensated CHF patients. So far, little is known about the stability of these vascular volumes and possible volume excess in compensated CHF patients over time. METHODS AND RESULTS This study aims at quantification of blood volume and its components, RCV and PV (raw values and adjusted for sex and anthropometric characteristics, expressed as per cent of the expected normal value), using an abbreviated carbon monoxide (CO) rebreathing method (aCORM) in 14 patients (two women) with systolic CHF at baseline and at a follow-up visit after approximately 6 months. While a vast heterogeneity was observed concerning RCV (82% to 134% of normalized alues) and PV (72% to 131% of normalized values), the vascular volumes showed a mean change of 1.2% and -1.3% after a mean follow-up of 183 days. CONCLUSIONS The vascular volumes including individual volume excess appear to be stable in compensated CHF patients. The reason for this individual volume response concerning both RCV and PV in CHF remains unclear and deserves further clarification.