Icodextrin Versus Glucose Solutions for the Once-Daily Long Dwell in Peritoneal Dialysis: An Enriched Systematic Review and Meta-analysis of Randomized Controlled Trials

RATIONALE & OBJECTIVE

The efficacy and safety of icodextrin versus glucose-only peritoneal dialysis (PD) regimens is unclear. The aim of this study was to compare once-daily long-dwell icodextrin versus glucose among patients with kidney failure undergoing PD.

STUDY DESIGN

Systematic review of randomized controlled trials (RCTs), enriched with unpublished data from investigator-initiated and industry-sponsored studies.

SETTING & STUDY POPULATIONS

Individuals with kidney failure receiving regular PD treatment enrolled in clinical trials of dialysate composition.

SELECTION CRITERIA FOR STUDIES

Medline, Embase, CENTRAL, Ichushi Web, 10 Chinese databases, clinical trials registries, conference proceedings, and citation lists from inception to November 2018. Further data were obtained from principal investigators and industry clinical study reports.

DATA EXTRACTION

2 independent reviewers selected studies and extracted data using a prespecified extraction instrument.

ANALYTIC APPROACH

Qualitative synthesis of demographics, measurement scales, and outcomes. Quantitative synthesis with Mantel-Haenszel risk ratios (RRs), Peto odds ratios (ORs), or (standardized) mean differences (MDs). Risk of bias of included studies at the outcome level was assessed using the Cochrane risk-of-bias tool for RCTs.

RESULTS

19 RCTs that enrolled 1,693 participants were meta-analyzed. Ultrafiltration was improved with icodextrin (medium-term MD, 208.92 [95% CI, 99.69-318.14] mL/24h; high certainty of evidence), reflected also by fewer episodes of fluid overload (RR, 0.43 [95% CI, 0.24-0.78]; high certainty). Icodextrin-containing PD probably decreased mortality risk compared to glucose-only PD (Peto OR, 0.49 [95% CI, 0.24-1.00]; moderate certainty). Despite evidence of lower peritoneal glucose absorption with icodextrin-containing PD (medium-term MD, -40.84 [95% CI, -48.09 to-33.59] g/long dwell; high certainty), this did not directly translate to changes in fasting plasma glucose (-0.50 [95% CI, -1.19 to 0.18] mmol/L; low certainty) and hemoglobin A_1c levels (-0.14% [95% CI, -0.34% to 0.05%]; high certainty). Safety outcomes and residual kidney function were similar in both groups; health-related quality-of-life and pain scores were inconclusive.

LIMITATIONS

Trial quality was variable. The follow-up period was heterogeneous, with a paucity of assessments over the long term. Mortality results are based on just 32 events and were not corroborated using time-to-event analysis of individual patient data.

CONCLUSIONS

Icodextrin for once-daily long-dwell PD has clinical benefit for some patients, including those not meeting ultrafiltration targets and at risk for fluid overload. Future research into patient-centered outcomes and cost-effectiveness associated with icodextrin is needed.

Biocompatible dialysis fluids for peritoneal dialysis

BACKGROUND

Biocompatible peritoneal dialysis (PD) solutions, including neutral pH, low glucose degradation product (GDP) solutions and icodextrin, have previously been shown to favourably influence some patient-level outcomes, albeit based on generally sub-optimal quality studies. Several additional randomised controlled trials (RCT) evaluating biocompatible solutions in PD patients have been published recently. This is an update of a review first published in 2014.

OBJECTIVES

This review aimed to look at the benefits and harms of biocompatible PD solutions in comparison to standard PD solutions in patients receiving PD.

SEARCH METHODS

The Cochrane Kidney and Transplant Specialised Register was searched up to 12 February 2018 through contact with the Information Specialist using search terms relevant to this review. Studies in the Specialised Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

All RCTs and quasi-RCTs in adults and children comparing the effects of biocompatible PD solutions (neutral pH, lactate-buffered, low GDP; neutral pH, bicarbonate(± lactate)-buffered, low GDP; glucose polymer (icodextrin)) in PD were included. Studies of amino acid-based solutions were excluded.

DATA COLLECTION AND ANALYSIS

Two authors extracted data on study quality and outcomes. Summary effect estimates were obtained using a random-effects model, and results were expressed as risk ratios and 95% confidence intervals (CI) for categorical variables, and mean differences (MD) or standardised mean differences (SMD) and 95% CI for continuous variables.

MAIN RESULTS

This review update included 42 eligible studies (3262 participants), including six new studies (543 participants). Overall, 29 studies (1971 participants) compared neutral pH, low GDP PD solution with conventional PD solution, and 13 studies (1291 participants) compared icodextrin with conventional PD solution. Risk of bias was assessed as high for sequence generation in three studies, allocation concealment in three studies, attrition bias in 21 studies, and selective outcome reporting bias in 16 studies.Neutral pH, low GDP versus conventional glucose PD solutionUse of neutral pH, low GDP PD solutions improved residual renal function (RRF) preservation (15 studies, 835 participants: SMD 0.19, 95% CI 0.05 to 0.33; high certainty evidence). This approximated to a mean difference in glomerular filtration rate of 0.54 mL/min/1.73 m2 (95% CI 0.14 to 0.93). Better preservation of RRF was evident at all follow-up durations with progressively greater preservation observed with increasing follow up duration. Neutral pH, low GDP PD solution use also improved residual urine volume preservation (11 studies, 791 participants: MD 114.37 mL/day, 95% CI 47.09 to 181.65; high certainty evidence). In low certainty evidence, neutral pH, low GDP solutions may make little or no difference to 4-hour peritoneal ultrafiltration (9 studies, 414 participants: SMD -0.42, 95% CI -0.74 to -0.10) which approximated to a mean difference in peritoneal ultrafiltration of 69.72 mL (16.60 to 122.00 mL) lower, and may increase dialysate:plasma creatinine ratio (10 studies, 746 participants: MD 0.01, 95% CI 0.00 to 0.03), technique failure or death compared with conventional PD solutions. It is uncertain whether neutral pH, low GDP PD solution use led to any differences in peritonitis occurrence, hospitalisation, adverse events (6 studies, 519 participants) or inflow pain (1 study, 58 participants: RR 0.51, 95% CI 0.24 to 1.08).Glucose polymer (icodextrin) versus conventional glucose PD solutionIn moderate certainty evidence, icodextrin probably reduced episodes of uncontrolled fluid overload (2 studies, 100 participants: RR 0.30, 95% CI 0.15 to 0.59) and augmented peritoneal ultrafiltration (4 studies, 102 participants: MD 448.54 mL/d, 95% CI 289.28 to 607.80) without compromising RRF (4 studies, 114 participants: SMD 0.12, 95% CI -0.26 to 0.49; low certainty evidence) which approximated to a mean creatinine clearance of 0.30 mL/min/1.73m2 higher (0.65 lower to 1.23 higher) or urine output (3 studies, 69 participants: MD -88.88 mL/d, 95% CI -356.88 to 179.12; low certainty evidence). It is uncertain whether icodextrin use led to any differences in adverse events (5 studies, 816 participants) technique failure or death.

AUTHORS' CONCLUSIONS

This updated review strengthens evidence that neutral pH, low GDP PD solution improves RRF and urine volume preservation with high certainty. These effects may be related to increased peritoneal solute transport and reduced peritoneal ultrafiltration, although the evidence for these outcomes is of low certainty due to significant heterogeneity and suboptimal methodological quality. Icodextrin prescription increased peritoneal ultrafiltration and mitigated uncontrolled fluid overload with moderate certainty. The effects of either neutral pH, low GDP solution or icodextrin on peritonitis, technique survival and patient survival remain uncertain and require further high quality, adequately powered RCTs.

Longitudinal analysis of cardiac structure and function in incident-automated peritoneal dialysis: comparison between icodextrin solution and glucose-based solution

Background

This study aimed to evaluate the longitudinal changes in cardiac structure and function in incident-automated peritoneal dialysis (APD) patients.

Methods

We conducted a 2-year prospective, randomized, open-label, parallel-group study to compare the efficacy of icodextrin solution versus glucose-based solution. Echocardiography was performed at baseline, 1 and 2 years. Echocardiographic parameters over 2 years were evaluated for each group, using the Friedman test. Generalized linear regression analysis was used to test the associations between baseline clinical variables and echocardiographic changes, and a multivariate model was used to analyze cardiac function between the two groups.

Results

A total of 43 APD patients were enrolled in the beginning of this study. Twenty patients in the icodextrin group (ICO) and 18 patients in the glucose group (GLU) completed the study. In left ventricular (LV) systolic function measurements, ejection fraction (EF) increased significantly in the GLU group. Measurements of LV diastolic function and septal early mitral annulus velocity (EMV) increased significantly from baseline to 24-months in the ICO group (5.43–5.51 ms). The GLU group showed a significant decrease in peak early diastolic velocity (EDV) (70.67–68.25 cm/s), but a significant increase in septal EMV (5.94–7.57 ms) from baseline to 24-months. No significant association was found between the baseline clinical variables and echocardiographic changes within 24 months in the generalized linear regression analysis. Multivariate models were used to investigate changes in the four primary endpoints, namely, myocardial performance index (MPI), left ventricular ejection fraction (LVEF), deceleration time (DT), and E/e′ ratio. These primary endpoints show no significant association with the baseline values in both the ICO and GLU groups.

Conclusion

The present study demonstrates that long-dwell icodextrin solution can maintain reasonable cardiac structure and function in incident-APD patients.

Trial registration

ISRCTN14931270 (retrospectively registered on 23/03/2018).

Icodextrin and peritoneal dialysis: advantages and new applications

The impact of icodextrin (ico) on peritoneal dialysis (PD) extension and patient survival is well established. Predominantly, ico-based solutions were prescribed in high-transporter PD patients. Advantages of the ico-based solutions include increased biocompatibility, avoidance of glucotoxicity, enhanced ultrafiltration failure (UF), sodium removal rates, better metabolic and blood pressure control. Bimodal solutions and twice daily exchanges of ico-based solutions are two newly introduced strategies to avoid glucose exposure and/or enhance UF in PD patients with UF failure. In addition, a simplified schedule of PD using a single nocturnal exchange of ico in patients with refractory congestive heart failure may represent an alternative option to manage fluid removal and azotaemia. The use of a simplified schedule of PD with only two ico exchanges or a single ico exchange is a challenging approach for end-stage renal disease patients with preserved residual function who desire to initiate PD.

Effect of Icodextrin Solution on the Preservation of Residual Renal Function in Peritoneal Dialysis Patients: A Randomized Controlled Study

Although icodextrin solution has been highlighted in the fluid management compared to glucose-based solutions, proof of a beneficial effect of icodextrin solution on residual renal function (RRF) is lacking. We conducted a multicenter prospective randomized controlled open-label trial to investigate whether icodextrin solution can preserve RRF.One hundred patients with urine volume ≥750 mL/day from 8 centers in Korea were randomly assigned to receive 1 exchange of icodextrin solution for a ≥8 hour-dwell time and 2 exchanges of 1.5% glucose-based biocompatible neutral pH solution or 1 exchange of ≥2.5% and 2 exchanges of 1.5% glucose-based biocompatible solutions. Using mixed-effects general linear models, we analyzed changes in residual glomerular filtration rate (GFR) and daily urine volume at 1 year.Forty-nine patients were assigned to the icodextrin group and 51 to the glucose solution group. During follow-up, the slope of the decline in residual GFR was -0.170 mL/min/month/1.73 m² in the icodextrin group, while it was -0.155 mL/min/month/1.73 m² in the glucose solution group (95% confidence interval [CI], -0.06 to 0.10; P = 0.701). Daily urine volume decreased faster in the glucose solution group than in the icodextrin group (-31.02 vs -11.88 mL per month; 95% CI, -35.85 to -2.44; P = 0.025). Results were consistent when we analyzed using intention-to-treat and per protocol principles. There were no differences in fluid status, peritoneal ultrafiltration, and peritoneal transport between groups during follow-up.This study clearly showed that icodextrin solution preserves residual urine volume better than glucose solution.

Biocompatible dialysis fluids for peritoneal dialysis

BACKGROUND

The longevity of peritoneal dialysis (PD) is limited by high rates of technique failure, some of which stem from peritoneal membrane injury. 'Biocompatible' PD solutions have been developed to reduce damage to the peritoneal membrane.

OBJECTIVES

This review aimed to look at the benefits and harms of biocompatible PD solutions in comparison to standard PD solutions in patients receiving PD.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register (28 February 2013), through contact with the Trials Search Co-ordinator using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE and EMBASE, and handsearching conference proceedings.

SELECTION CRITERIA

All randomised controlled trials (RCTs) and quasi-RCTs in adults and children comparing the effects of biocompatible PD solutions (neutral pH, lactate-buffered, low glucose degradation product (GDP); neutral pH, bicarbonate (± lactate)-buffered, low GDP; glucose polymer (icodextrin)) in PD were included. Studies of amino acid-based PD solutions were excluded.

DATA COLLECTION AND ANALYSIS

Two authors extracted data on study quality and outcomes (including adverse effects). The authors contacted investigators to obtain missing information. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for categorical variables, and mean difference (MD) or standardised mean difference (SMD) and 95% CI for continuous variables.

MAIN RESULTS

Thirty-six eligible studies (2719 patients) were identified: Neutral pH, lactate-buffered/bicarbonate (± lactate)-buffered, low GDP PD solution (24); icodextrin (12). Allocation methods and concealment were generally incompletely reported, and adequate in only ten studies (27.8%). Patients lost to follow-up ranged from 0% to 83.4%. Neutral pH, low GDP versus conventional glucose PD solutionBased on generally sub-optimal quality evidence, the use of neutral pH, low GDP PD solutions was associated with larger urine volumes at the end of the studies, up to three years of therapy duration (7 studies, 520 patients: MD 126.39 mL/d, 95% CI 26.73 to 226.05). Improved preservation of residual renal function was evident in studies with greater than 12 month follow-up (6 studies, 360 patients: SMD 0.31, 95% CI 0.10 to 0.52). There was no significant effect on peritonitis, technique failure or adverse events with the use of neutral pH, low GDP PD solutions. Glucose polymer (icodextrin) versus conventional glucose PD solutionThere was a significant reduction in episodes of uncontrolled fluid overload (2 studies, 100 patients: RR 0.30, 95% CI 0.15 to 0.59) and improvement in peritoneal ultrafiltration (4 studies, 102 patients, MD 448.54 mL/d, 95% CI 289.28 to 607.80) without compromising residual renal function (4 studies, 114 patients: SMD 0.12, 95% CI -0.26 to 0.49) or urine output (3 studies, 69 patients: MD -88.88 mL/d, 95% CI -356.88 to 179.12) with icodextrin use. A comparable incidence of adverse events with the icodextrin (four studies) was reported.

AUTHORS' CONCLUSIONS

Based on generally sub-optimal quality studies, use of neutral pH, low GDP PD solution led to greater urine output and higher residual renal function after use exceeded 12 months. Icodextrin prescription improved peritoneal ultrafiltration and mitigated uncontrolled fluid overload. There were no significant effects on peritonitis, technique survival, patient survival or harms identified with their use. Based on the best available evidence, the use of these 'biocompatible' PD solutions resulted in clinically relevant benefits without added risks of harm.

Effect of peritoneal dialysis modality on the 1-year rate of decline of residual renal function

PURPOSE

The effect of different peritoneal dialysis (PD) modalities on the decline in residual renal function (RRF) is unclear due to inconsistencies among studies. In particular, the effect of automated peritoneal dialysis (APD) modalities [continuous cyclic peritoneal dialysis (CCPD) and nightly intermittent peritoneal dialysis (NIPD)] on RRF has not been examined in a large cohort.

MATERIALS AND METHODS

We conducted a single-center retrospective study to investigate the association between PD modalities and decline in RRF in 142 incident PD patients [34 on CCPD, 36 on NIPD, and 72 on continuous ambulatory peritoneal dialysis (CAPD)]. RRF was measured within 2 months from PD start and at 1 year after PD initiation.

RESULTS

The RRF at 1 year after PD initiation was 1.98±2.20 mL/min/1.73 m² in CCPD patients and 3.63±3.67 mL/min/1.73 m² in NIPD patients, which were moderately lower than 4.23±3.51 mL/min/1.73 m² in CAPD patients (p=0.064). Moreover, there was no significant difference in the 1-year rate of decline of RRF between CCPD and NIPD patients, although APD patients had a faster 1-year RRF decline rate than CAPD patients (CCPD and NIPD vs. CAPD: -45.68 and -36.69 vs. 1.17%/year, p=0.045). APD was associated with a more rapid decline in RRF in patients with end-stage renal disease undergoing PD, although multivariate analysis attenuated the significance of this finding (β=-31.50; 95% CI, -63.61 to 0.62; p=0.052).

CONCLUSION

Our results suggest that CAPD might be more helpful than APD for preserving RRF during the first year of dialysis therapy, although there was no significant difference in the 1-year rate of decline of RRF between the two APD modalities.

Bimodal solutions or twice-daily icodextrin to enhance ultrafiltration in peritoneal dialysis patients

The efficacy and safety of icodextrin has been well established. In this paper, we will discuss the pharmacokinetics and biocompatibility of icodextrin and its clinical effect on fluid management in peritoneal dialysis patients. Novel strategies for its prescription for peritoneal dialysis patients with inadequate ultrafiltration are reviewed.

Decline in residual renal function in automated compared with continuous ambulatory peritoneal dialysis

BACKGROUND AND OBJECTIVES

We compared the decline of RRF in patients starting dialysis on APD with those starting on CAPD, because a faster decline on APD has been suggested.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

NECOSAD patients starting dialysis on APD or CAPD with RRF at baseline were included and followed for 3 years. Residual GFR (rGFR) was the mean of urea and creatinine clearances. Differences in yearly decline of rGFR were estimated in analyses with linear repeated measures models, whereas the risk of complete loss of RRF was estimated by calculating hazard ratios (HRs) for APD compared with CAPD. As-treated (AT) and intention-to-treat (ITT) designs were used. All of the analyses were adjusted for age, gender, comorbidity, and primary kidney disease and stratified according to follow-up and mean baseline GFR.

RESULTS

The 505 CAPD and 78 APD patients had no major baseline differences. No differences were found in the analyses on yearly decline of rGFR. APD patients did have a higher risk of losing RRF in the first year (ITT crude HR 2.43 [confidence interval 95%, 1.48 to 4.00], adjusted 2.66 [1.60 to 4.44]; AT crude 1.89 [1.04 to 3.45], adjusted 2.15 [1.16 to 3.98]). The higher risk of losing all RRF was most pronounced in patients with the highest rGFR at baseline (ITT; crude 3.91 [1.54 to 9.94], adjusted 1.85 to 14.17).

CONCLUSIONS

The risk of losing RRF is higher for patients starting dialysis on APD compared with those starting on CAPD, especially in the first year.

Risk factors for high dialysate glucose use in PD patients--a retrospective 5-year cohort study

BACKGROUND

Use of high concentrations of glucose for peritoneal dialysis (PD) may produce unfavorable results. Our previous study showed that high initial glucose load is associated with poor PD technique survival.

OBJECTIVE

This retrospective cohort study at a medical center in Taiwan aimed to understand the factors associated with high glucose load in long-term PD patients.

PATIENTS AND METHODS

We reviewed 90 newly started PD patients over 5 years. We determined glucose load by calculating annual glucose weight and dialysate volume administered. Multiple linear regression analyses with time-dependent covariates were used to determine factors that influence the annual average dialysate glucose concentration.

RESULTS

The study group included 47 men and 43 women with a mean age of 53.4 +/- 13.9 years. Technique survival rates were 91.0%, 84.1%, and 77.6% at the beginning of the second, third, and fourth year of PD therapy respectively. The presence of diabetes mellitus (DM), high body mass index (BMI), and low weekly renal Kt/V were significantly correlated with high average dialysate glucose concentration during the first, second, and third years. For patients undergoing PD for more than 3 years, residual renal function (RRF) deteriorated, and only DM significantly affected higher dialysate glucose concentration in the fourth year.

CONCLUSIONS

Patients with DM, high BMI, and low RRF were more likely to require a high glucose load for PD therapy, especially during the first 3 years. After those 3 years of PD, DM was the only significant factor in the need for higher glucose load. To reduce the glucose load in chronic PD patients, alternative osmotic agents such as icodextrin or amino acids should be considered in the daily PD regimen.

Angiotensin Receptor Blocker Telmisartan Improves Insulin Sensitivity in Peritoneal Dialysis Patients

Background

Insulin resistance (IR) is common among patients on dialysis and is worse among patients on peritoneal dialysis (PD) than among patients on hemodialysis. In this study we tested the hypothesis that administration of telmisartan, an angiotensin II type 1 receptor antagonist, might improve insulin sensitivity in patients on PD.

Method

This was a crossover study of 30 nondiabetic patients with end-stage renal disease being treated with PD. Group A patients ( n = 15) received telmisartan and other antihypertensive drugs for 4 months, followed by 4 months without telmisartan. Group B patients ( n = 15) received their usual treatment for 4 months, followed by 4 months of treatment with telmisartan. Blood glucose and serum insulin levels were monitored and homeostasis model assessment method for IR (HOMA-IR) was calculated.

Results

Treatment with telmisartan had no significant impact on serum glucose, potassium, and bicarbonate levels. However, telmisartan significantly reduced serum insulin levels and the HOMA index in groups A and B.

Conclusion

This study demonstrated that telmisartan, an angiotensin receptor type 1 antagonist, may effectively improve insulin sensitivity as measured by HOMA in patients treated with PD.

A Combined Crystalloid and Colloid PD Solution as a Glucose-Sparing Strategy for Volume Control in High-Transport APD Patients: A Prospective Multicenter Study

Background

Evidence is accumulating that the continuous exposure to high glucose concentrations during peritoneal dialysis (PD) is an important cause of ultrafiltration (UF) failure. The cornerstone of prevention and treatment of UF failure is reduction of glucose exposure, which will also alleviate the systemic impact of significant free glucose absorption. The challenge for the future is to discover new therapeutic strategies to enhance fluid and sodium removal while diminishing glucose load and exposure using combinations of available osmotic agents.

Objectives

To investigate in patients on automated PD (APD) with a fast transport pattern whether there is a glucose-sparing advantage to replacing 7.5% icodextrin (ICO) during the long dwell with a mixed crystalloid and colloid PD fluid (bimodal UF) in an attempt to promote daytime UF and sodium removal while diminishing the glucose strength of the dialysate at night.

Design

A 2 parallel arm, 4 month, prospective nonrandomized study.

Setting

PD units or university hospitals in 4 French and Belgian districts.

Results

During the 4-month intervention period, net UF and peritoneal sodium removal during the long dwell when treated by bimodal UF was about 2-fold higher than baseline (with ICO). The estimated percent change (95% confidence interval) from baseline in net daytime UF for the bimodal solution was 150% (106% – 193%), versus 18% (–7% – 43%) for ICO ( p < 0.001). The estimated percent change from baseline in peritoneal sodium removal for the bimodal solution was 147% (112% – 183%), versus 23% (–2% – 48%) for ICO ( p < 0.001). The estimated percent change from baseline in UF efficiency (24-hour net UF divided by the amount of glucose absorbed) was significantly higher ( p < 0.001) when using the bimodal solution was 71%, versus -5% for ICO.

Conclusion

Prescription of bimodal UF during the day in APD patients offers the opportunity to optimize the long dwell exchange in a complete 24-hour APD cycle. The current study demonstrated that a bimodal solution based on the mixing of glucose (2.6%) and icodextrin (6.8%) achieved the double target of significantly improving UF and peritoneal sodium removal by exploring a new concept of glucose-sparing PD therapy.

Peripheral Resistance Modulates the Response to Volume Overload in Peritoneal Dialysis Patients

Background

Volume overload is thought to be the most important cause of hypertension in peritoneal dialysis (PD) patients. However, there is also evidence that normalization of volume overload is not always accompanied by a drop in blood pressure (BP). In the present study, we hypothesized that dysregulation of peripheral resistance due to endothelial dysfunction would constitute an important determinant of BP response in overhydrated PD patients.

Methods

We performed an observational, prospective cohort study including all prevalent PD patients at the Peking University Third Hospital between 1 June 2006 and 30 November 2006. After baseline measurements, including echocardiography and bioelectrical impedance analysis, patients fulfilling inclusion criteria were reevaluated after 2 months of follow-up. All patients that exhibited significant changes in BP and extracellular water (ECW) between 2 visits were asked to undergo a second ultrasound. These patients were then divided into group A (parallel change between BP and ECW; n = 12) and group B (paradoxical change between BP and ECW; n = 10).

Results

The cohort included 22 patients (13 males) with a mean age of 59 ± 13 years, on dialysis for 23.3 ± 32.6 months. There were no baseline differences between groups A and B. However, while patients in group A significantly increased their cardiac output, total peripheral resistance remained stable. In group B, cardiac output did not change significantly but total peripheral resistance decreased significantly.

Conclusion

In PD patients, a significant increase in fluid volume is not necessarily linked to a significant increase in BP. Rather, the change in total peripheral resistance was found to be the most important determinant of the extent to which increased fluid volume affected BP.

The contribution of combined crystalloid and colloid osmosis to fluid and sodium management in peritoneal dialysis

The achievement of euvolemia is essential to the successful management of peritoneal dialysis patients. However, the concern that hypertonic glucose exchanges may have a role in long-term changes to the peritoneal membrane has lead to an alternative strategy to enhance ultrafiltration (UF) over the long dwell by combining crystalloid and colloid osmosis. This review summarizes the experience of mixing glucose or amino acids with polyglucose (icodextrin), with particular focus given to data from studies using glucose/icodextrin in combinations of 1.36%/7.5% and 2.61%/6.8%. Both combinations demonstrate a significant increment of UF volume and sodium removal compared with the component osmotic agents used individually over long dwells, with the 2.61%/6.8% mixture having an effect over dwells extending to 15 h. Hypothetically, the mechanism of the enhanced UF is the attenuation by the colloid osmotic force of the backflow of water through small pores from dialysate to the peritoneal capillary circulation once the crystalloid osmotic force has dissipated. This experience provides promising data that deserves further examination in longer term clinical studies.