Assessment of Postresuscitation Volume Status by Bioimpedance Analysis in Patients with Sepsis in the Intensive Care Unit: A Pilot Observational Study.

Background. Bioimpedance analysis (BIA) is a novel method of assessing a patient's volume status. Objective. We sought to determine the feasibility of using vector length (VL), derived from bioimpedance analysis (BIA), in the assessment of postresuscitation volume status in intensive care unit (ICU) patients with sepsis. Method. This was a prospective observational single-center study. Our primary outcome was feasibility. Secondary clinical outcomes included ventilator status and acute kidney injury. Proof of concept was sought by correlating baseline VL measurements with other known measures of volume status. Results. BIA was feasible to perform in the ICU. We screened 655 patients, identified 78 eligible patients, and approached 64 for consent. We enrolled 60 patients (consent rate of 93.8%) over 12 months. For each 50-unit increase in VL, there was an associated 22% increase in the probability of not requiring invasive mechanical ventilation (IMV) (p = 0.13). Baseline VL correlated with other measures of volume expansion including serum pro-BNP levels, peripheral edema, and central venous pressure (CVP). Conclusion. It is feasible to use BIA to predict postresuscitation volume status and patient-important outcomes in septic ICU patients. Trial Registration. This trial is registered with clinicaltrials.gov NCT01379404 registered on June 7, 2011.

Continued transplant immunosuppression may prolong survival after return to peritoneal dialysis: results of a decision analysis.

BACKGROUND: Patient survival is prolonged in those with residual renal function. The risks of opportunistic infection and malignancy militate against a widespread policy of maintaining immunosuppression in those returning to peritoneal dialysis after a failed allograft. We set out to test the hypothesis that patients returning to peritoneal dialysis after a failed transplant benefit from continued immunosuppression. METHOD: A decision analytic model comparing the use of immunosuppression after transplant failure and return to peritoneal dialysis with immunosuppressive withdrawal. Two assumptions were made: that the survival benefit reported in patients with a transplant kidney was the same as that expected from a native kidney with a similar glomerular filtration rate (GFR) and that the risks of carcinoma and opportunistic infections were equal to that of the general population if immunosuppressive therapy was discontinued. Probabilities were obtained from the literature, from an administrative database, and from the rate of GFR decline seen in our own unit in patients returning to dialysis who had been discontinued from their transplant immunosuppressive medication. RESULTS: Life expectancy was prolonged from 5.3 years to 5.8 years when immunosuppression was continued in patients who returned to dialysis after chronic allograft failure. A higher survival benefit was seen at higher levels of additional GFR. A benefit from continued immunosuppressive therapy was seen for all values of additional GFR greater than 15 L/wk. All dialysis and renal clearances have been expressed as L/wk. The conversion factors for conversion to mL/s and mL/min are 605 and 10.1. CONCLUSION: The data suggest that there may be a survival advantage in maintaining patients on long-term immunosuppressive function even after they return to peritoneal dialysis after allograft failure.

A novel regional citrate anticoagulation protocol for CRRT using only commercially available solutions.

PURPOSE: To describe a citrate regional anticoagulation (CRA) protocol for patients with acute renal failure and contraindications to heparin who require continuous renal replacement therapy (CRRT), using only commercially available solutions, for units that do not want or cannot prepare extemporaneously made solutions. MATERIALS AND METHODS: Case report and series from a medical/surgical intensive care unit of a university teaching hospital. A CRA protocol was developed by using only commercially available solutions. Five dialysis-specific clinical parameters were identified to allow simplified measurement and control. RESULTS: There was a dramatic improvement of dialysis filter survival in the index patient that was seen in the subsequent patients receiving CRA. This was accompanied by excellent control of the clinical and biochemical parameters as well as nursing acceptance and ownership of the protocol. CONCLUSION: It is possible to provide safe and effective CRA with only commercially available solutions. The protocol is applicable to most patients requiring CRRT.

Effects of intraperitoneal hyaluronan on peritoneal fluid and solute transport in peritoneal dialysis patients.

BACKGROUND: Hyaluronan (HA) is a glycosaminoglycan found in connective tissues and tissue spaces, including the peritoneal cavity. In vivo studies in a rat model of peritoneal dialysis (PD) have shown that addition of HA to PD solution during an intraperitoneal dwell can alter peritoneal fluid transport and protect the peritoneal membrane from the effects of inflammation and repeated infusions of dialysis solution. The current study sought to evaluate the safety of intraperitoneal HA and its effect on peritoneal fluid and solute transport when administered during a dialysis dwell in humans. METHODS: 13 PD patients were enrolled in a prospective, randomized crossover study involving three dialysis treatments using the following PD solutions: (1) a commercially available PD solution (Dianeal PD-4, 1.36% glucose; Baxter Healthcare Corporation, Alliston, Ontario, Canada); (2) Dianeal PD-4 containing 0.1 g/L HA, and (3) Dianeal PD-4 containing 0.5 g/L HA. Each 6-hour dialysis exchange was separated from the other exchanges by a 2-week washout period. Radioiodinated human serum albumin (RISA) was administered with the dialysis solution to evaluate intraperitoneal volume, net ultrafiltration (UF), and fluid reabsorption. Peritoneal clearances, dialysate/plasma ratios (D/P), and mass transfer area coefficients (MTACs) were determined for sodium, urea, creatinine, albumin, and glucose. Safety was evaluated by monitoring adverse events and changes in serum chemistries. Ten patients completed all three dialysis exchanges and two additional patients completed at least one treatment exchange. RESULTS: There were no reported adverse events related to HA administration and no significant changes in serum chemistries. There were no significant differences in net UF or peritoneal volume profiles among the three treatments. Mean net UF calculated using residual volumes, estimated by RISA dilution, tended to be slightly higher during treatment with solution containing 0.1 g/L HA and 0.5 g/L HA [74 +/- 86 (SE) and 41 +/- 99 mL, respectively] compared to control treatment (-58 +/- 129 mL). Although not statistically significant, there was a trend toward decreased fluid reabsorption during treatment with HA. Solute clearances, D/P ratios, and MTACs were similar for the three treatments. Serum levels of HA were also unaffected by the two treatment solutions. CONCLUSIONS: These data support the acute safety of HA when administered intraperitoneally with the dialysis solution to PD patients. Due to the small sample size and variability in net UF and fluid reabsorption, statistically significant differences were not demonstrated for these parameters. However, a trend toward decreased fluid reabsorption was observed, suggesting that HA may act by a mechanism similar to that observed in animal studies. Further studies are necessary to evaluate whether the beneficial effects of HA observed in animal studies can be shown in humans.

Analysis of factors predicting survival of a second peritoneal dialysis catheter.

Many studies have examined the survival of the first peritoneal dialysis (PD) catheter. However, data are scarce about the factors that influence the function and survival time of a second PD catheter. The purpose of the present study was to calculate the survival time of the second PD catheter and to examine factors that predict removal of that catheter. We conducted a retrospective study of second PD catheters inserted at our institution over a 10-year period from May 1992 to April 2002. The endpoint consisted of removal of the second catheter. Voluntary change to hemodialysis, kidney transplantation, transfer to another center, and death with a functioning catheter were censored observations. Catheter survival was analyzed by the Kaplan-Meier method. During the study period, 106 patients (59 men, 47 women) received a second catheter. The mean age of the patients was 55 +/- 14.9 years. One third of the patients had diabetes. The reasons for removal of the first catheter and insertion of the second one were peritonitis (n = 50), catheter malfunction (n = 20), catheter leak (n = 11), exit site or tunnel infection (n = 21), and failed kidney transplantation with resumption of PD (n = 4). The median survival of the second catheter was 48 months (95% confidence interval: 38 months to 59 months). On univariate analysis, increasing patient age and peritonitis as cause for removal of the first catheter were associated with an increased risk of removal of the second catheter. However, on multivariate analysis, only increasing patient age was associated with a greater risk to survival of the second catheter.