Catheter-related bacteremia in hemodialysis patients: the role of the central venous catheter in prevention and therapy.

Infections are a leading cause of morbidity and mortality in patients with end-stage renal disease. Infections in hemodialysis patients are strongly associated with the use of an indwelling central venous catheter. S. aureus, coagulase-negative staphylococci and Gram-negative rods account for the majority of these infections. The outcome of catheter-related bacteremia depends on appropriate antibiotic therapy and management of the hemodialysis catheter. Most studies note that there is no difference in outcome if the catheter is changed over a guidewire in addition to antibiotic therapy or if the catheter is completely removed and reinserted at a later date. However, bacteremia with certain organisms, particularly S. aureus, is associated with complications. Thus, the data suggests that the catheter needs to be promptly removed in patients developing S. aureus bacteremia.Bacterial biofilm likely has a critical role in the pathogenesis of these infections. Numerous in vitro and in vivo studies have demonstrated both a reduction in infection rate with the use of antibiotic catheter locks as well as a reduction in the production of or eradication of bacterial biofilm. Future studies ought to target, firstly, a reduction in the reliance on central venous catheters; and secondly, the formulation of practical strategies to reduce patient risk for developing catheter-related bacteremia.

Structural requirements for a successful chronic peritoneal dialysis program.

Recently, there has been a decline in chronic peritoneal dialysis (CPD) utilization in several countries. And, in these countries, the percent of patients with end-sage renal disease maintained on CPD is less than nephrologists think is appropriate. The reasons for these problems are uncertain, but it is likely that difficulties with the structural organization of CPD facilities play a contributory role. This paper discusses the structural requirements for a successful CPD program, focusing attention on the following domains: (1) adequate chronic kidney disease education, (2) provision and support of physician training in the principles and practice of CPD, (3) adequate size and organization of CPD centers, (4) development of appropriate support systems within the CPD facility, and (5) development of appropriate continuous quality improvement programs to monitor a variety of domains, including adequacy of dialysis, peritonitis rates, catheter infections and problems, psychosocial status of patients, etc.

Tidal PD: its role in the current practice of peritoneal dialysis.

The role of tidal peritoneal dialysis (TPD) has been the subject of several studies over the past 30 years. The use of the newest generation of cyclers combined with the increasing number of chronic peritoneal dialysis (CPD) patients being maintained on cycler therapy has stimulated a reexamination of the role of TPD in the care of CPD patients. Several studies over the past decade have examined solute clearances with TPD in patients. These studies suggest that TPD does not result in an increase in clearances when compared to conventional intermittent peritoneal dialysis (IPD). TPD is now primarily used for comfort in patients who experience pain at the start of inflow and/or at the end of outflow. In TPD, the presence of at least some fluid in the abdomen during the exchanges generally eliminates these episodes of pain. It has recently been suggested that accurate assessment of drain and fill phases during automated PD may be helpful in redefining a role for TPD in CPD patients. If the 'slow' drainage time can be kept to a minimum, then it is possible that the efficiency of PD could be enhanced. Defining the critical volume and then optimizing the TPD regimen could perhaps increase the clearances noted with TPD.

The impact of various cycling regimens on phosphorus removal in chronic peritoneal dialysis patients.

BACKGROUND: The National Kidney Foundation Dialysis Outcome Quality Initiative clinical practice guidelines have suggested that serum phosphate levels be maintained at < or =5.5 mg/dL in patients maintained on dialysis. Over 45% of anuric patients maintained on CAPD have serum phosphate levels >5.5 mg/dL. The present study was designed to address the question whether phosphate removal could be enhanced by increasing the dialysate volume during cycler peritoneal dialysis therapy. METHODS: Medically stable patients maintained on chronic peritoneal dialysis therapy, who were high or high-average transporters and had serum phosphate levels > or =5.5 mg/dL, were invited to participate in the study. The protocol involved measuring phosphate and creatinine clearances at weekly intervals on three different cycler prescriptions consisting of 7 and 12 full cycles or 24 cycles with 50% tidal PD (TPD) over 9 hours. Ten patients agreed to participate. Those patients (n=7) with a BMI > 22 had 2 liter (L) fill volumes and 14 L of total dialysate (7 cycles of 2 L) or 24 L total dialysate (12 cycles of 2 L or 50% TPD with 24 cycles).The patients (n=3) with a BMI < 20 had 1.2 L fill volumes and 8.4 L total dialysate (7 cycles) or 14.4 L total dialysate (12 cycles of 1.2 L or 50% TPD with 24 cycles). RESULTS: The mean age (+/- SD) of the study patients was 50.8 (+/- 9.3) years. There were 6 females, 6 Caucasians and 4 African-Americans. The mean weight of the patients was 71.5 (+/- 24.2) kg and mean height 1.65 (+ 7.6) meters. The mean BMI was 18.3 (+/- 1.27) in the < 20 BMI group and 30.3 (+/- 6.6) in the > 22 BMI group. The mean phosphate clearance (L/night/1.73m 2 ) increased from 3.96 (+/- 1.16) with 7 cycles to 4.71 (+ 1.81) with 12 cycles and 4.51 (+/- 1.61) with 50% TPD. Creatinine clearance (L/night/1.73m 2 ) was 4.74 (+/- 1.74) with 7 cycles, 6.06 (+/- 2.04) with 12 cycles and 5.61 (+/- 2.01) with TPD. CONCLUSION: The present study indicates that there is a significant, 19% (P < 0.005) rise in phosphate clearance by increasing dialysate volume 71% from 7 cycles to 14 cycles compared to a 27% increase in creatinine clearance. With tidal PD, phosphate clearance increased by 12% (p=NS) and creatinine clearance increased 18 % (p, 0.02). This increase in phosphate clearance translates into <50 mg net phosphate removal in 9 hours, assuming a serum phosphate of 6 mg/%. Thus, increasing dialysis cycles and volume results in only a minimal increase in net phosphate removal.

Erectile dysfunction in chronic peritoneal dialysis patients: incidence and treatment with sildenafil.

OBJECTIVES: Sexual and erectile dysfunction (ED) have been reported to occur frequently in male patients with end-stage renal disease maintained on dialysis. Numerous etiologies for this ED have been suggested. Although a variety of therapies for the ED of the dialysis patient have been suggested, most clinicians indicate that patients report a poor response to therapy. Recently, sildenafil has been reported to be beneficial in treating patients with ED of both organic and psychogenic causes. The present study was designed to document the incidence of ED in male patients maintained on chronic peritoneal dialysis (CPD) and to determine the efficacy of prescribing sildenafil therapy to treat their ED. METHODS: All male patients in our CPD unit were notified by letter of the availability of sildenafil as a treatment modality for ED. A sexuality/erectile dysfunction assessment was conducted in all male patients by their primary nephrologist. Patients who reported ED and who had no medical contraindication to sildenafil were offered this therapy. Those patients who were interested in this treatment were interviewed by a social worker, and patients were asked to complete the International Index of Erectile Function questionnaire. Sildenafil was prescribed at a starting dose of 25 mg and increased to a maximum of 100 mg during a 12-week study trial. Patients were re-evaluated 6 and 12 weeks after the start of therapy. RESULTS: There were 68 male patients maintained on CPD at the time of the study. Mean age of all patients was 60.8 +/- 15.3 years and mean duration on PD was 32.6 +/- 25.6 months. Thirty-three patients had diabetes, 66 hypertension, 35 peripheral vascular disease, and 32 coronary artery disease. Thirty-two of 68 male patients in the CPD unit were assessed to have ED. Only 17 of the 32 patients expressed interest in pursuing sildenafil therapy. Two of these patients were excluded because they were receiving nitrate therapy. Of the 15 patients who agreed to take sildenafil, only 6 completed the 12-week study. Two of these patients responded to sildenafil. CONCLUSION: Erectile dysfunction is common in male patients maintained on CPD. Only about half of patients with ED in the present study were willing to consider sildenafil therapy to treat the ED and, of those who agreed to treatment, only a minority completed the 12-week trial; 2 of these 6 patients reported a satisfactory response.

Method for studying development of colonization and infection of dialysis catheters.

Microbial colonization and infection of dialysis catheters is the major cause of catheter failure. The present study aimed to develop a method to permit the study of microbial biofilm formation and antibiotic prophylaxis and therapy. Standard silicon rubber and silver-impregnated catheters were sectioned into 1 mm slices and placed into 1-cm x 2-cm culture slide chambers. Fresh clinical isolates were obtained from infected patients and suspended in concentrations of 10(3), 10(6), and 10(9) colony forming units (CFU) per milliliter in a variety of liquid suspending culture media, which included serum protein constituents. Antibiotics could be added to the suspending fluid to determine prophylactic activity, or at any time thereafter to determine therapeutic activity. The catheter sections were incubated with the microbial challenge for 6 hours, 12 hours, 24 hours, and 48 hours and then washed in flowing distilled water to remove unattached biofilm. They were then stained with acridine orange, which fluoresces microbial DNA, and were examined by confocal scanning laser microscopy. Biofilm formation, representing colonization and infection, were quantified by comparing the fluorescent pixel analysis of the uninoculated control with the challenged catheter. The method was reproducible and permitted quantitative analysis. Standard silicon rubber catheters demonstrated greater biofilm formation than silver-impregnated catheters. The method examines the factors involved in microbial colonization and infection, and in antibiotic prophylaxis and therapy.

Identification and treatment of depression in a cohort of patients maintained on chronic peritoneal dialysis.

Depression is the most commonly encountered psychological problem in patients with end-stage renal disease (ESRD). Depression has recently been shown to significantly impact on the morbidity and mortality of patients undergoing therapy for ESRD. The present study was designed as a pilot study to evaluate the feasibility of screening a large cohort of patients maintained on chronic peritoneal dialysis (CPD) for depression and then pharmacologically treating those patients assessed to have clinical depression. One hundred thirty-six patients maintained on CPD in our CPD unit were screened for depression using the Beck Depression Inventory (BDI), a self-administered questionnaire. Patients with scores of 11 or greater were referred to a trained psychiatric interviewer for further evaluation to confirm the diagnosis of clinical depression and determine whether the patient was a candidate for antidepressant medication. Sixty-seven patients had BDI scores of 11 or greater, and 60 of these patients were asked to participate in further evaluation and possible therapy. Only 27 patients agreed to further study and were evaluated by a trained psychiatric interviewer for clinical depression. Twenty-three of these patients were assessed to have clinical depression, and 22 patients were eligible for antidepressant medication based on their scores on the Hamilton Depression Scale and psychiatric interview. Eleven patients completed a 12-week course of therapy with antidepressant medication, and their BDI scores decreased from a mean of 17.1 +/- 6.9 (SD) to a mean of 8.6 +/- 3.2. Seven patients were treated with sertraline, 2 patients with bupropion, and 2 patients with nefazodone. It is concluded that (1) depression is commonly present in patients maintained on CPD, (2) the BDI is a useful tool to use to screen for clinical depression, and (3) clinical depression is treatable with medication in this patient population.

Continuous peritoneal dialysis and the extended care facility.

The projected disproportionate increase in the number of elderly patients reaching end-stage renal disease constitutes a dramatic change in dialysis demographics. The nursing home or extended care facility (ECF) will become an increasingly important feature of care for both rehabilitation and long-term patient management. For continuous peritoneal dialysis (CPD), the ECF has been critically evaluated in only a single specialized, university-based, geriatric facility that included trained peritoneal dialysis nurses providing care. We have trained multiple ECF personnel in 10 community-based ECFs to provide all CPD-related therapy for 93 patients between November 1993 and December 1998, for a total of 289.3 patient-months. All ECFs have maintained their CPD program. Outcome measures, including hospitalization, mortality, technique failure, and peritonitis rates, show the success and feasibility of using community-based ECFs for CPD. The use of multiple ECFs for CPD appears to offer distinct advantages over solo structured ECF programs without jeopardizing outcomes. A highly structured CPD education program for ECF personnel by nephrology staff is manageable and appears critical for the success of maintaining CPD in the ECF.

Revascularization of renal artery stenosis in patients with renal insufficiency.

The incidence and prevalence of end-stage renal disease (ESRD), particularly in the elderly population, have continued to increase in the United States. It is estimated that 10% to 20% of the elderly patients with ESRD have potentially remediable renal vascular disease. The purpose of the present study is to examine the results of renal artery revascularization in 20 patients aged older than 55 years with chronic renal failure (serum creatinine level >2 mg/dL) with proximal renal artery stenosis (RAS) diagnosed by magnetic resonance angiography (MRA) who underwent surgical or percutaneous revascularization. Patients were followed up closely in the postrevascularization period; renal function was monitored and potential complications of the procedure were carefully noted. Four of the 20 patients developed serious complications, including 3 patients with clinically significant atheroembolic disease and 1 patient with renal artery dissection. Seven patients developed greater than 5% eosinophilia. Five of the 20 patients had a deterioration in renal function 3 to 6 months after the procedure, and only 5 patients had a reduction in serum creatinine concentration 3 to 6 months after the procedure. The present study suggests that in elderly patients with chronic renal failure and proximal RAS, revascularization of renal vessels is associated with a high complication rate, and improvement in renal function occurs in only 25% of the patients. Whether revascularization can slow the rate of progression of renal failure remains uncertain and can only be answered by a large prospective trial.

Tidal peritoneal dialysis: comparison of different tidal regimens and automated peritoneal dialysis.

BACKGROUND: The National Kidney Foundation Dialysis Outcomes Quality Initiative (DOQI) clinical practice guidelines have suggested minimal weekly Kt/V urea and creatinine clearance goals for peritoneal dialysis patients maintained on continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis (APD). Achieving these goals may present problems, particularly in larger patients whose residual renal function declines. Thus, modifications of the dialysis regimen, such as tidal peritoneal dialysis (TPD), have been developed. However, the ability of TPD to improve the efficiency of the dialysis procedure remains uncertain. METHODS: Stable, cycling peritoneal dialysis patients were placed into two groups to study the effectiveness of different TPD prescriptions on peritoneal clearances of urea and creatinine. The volume of dialysis solution used and the duration of therapy were fixed in the two groups. Comparisons were made to conventional APD using multiple hourly cycles in which spent dialysis solution was completely drained with each cycle. Group I patients received a total of 15 L of PD solution over 9.5 hours in the dialysis unit. These patients received 10, 25, and 50% TPD and APD on four separate days. Group II patients received 24 L of PD solution over 9.5 hours. These patients received 25 and 50% APD on separate days in the dialysis unit. Peritoneal dialysis clearances for urea (pKt/V) and creatinine (pCCr) levels were calculated for both groups. The results were then analyzed to determine whether there was any significant difference among the various prescriptions. RESULTS: The data in the group I patients indicated a mean daily pKt/V of 0.22 +/- 0.03 with 10% TPD, 0.23 +/- 0.02 with 25% TPD, 0.25 +/- 0.02 with 50% TPD, and 0.26 +/- 0.02 with APD. Paired t-test analysis for pKt/V demonstrated that 10 and 25% TPD resulted in significantly lower values than 50% TPD and APD (P < 0.05). Mean daily pCCr L/24 h/1.73 m2 was 6.03 +/- 0.72 for 10% TPD, 6.34 +/- 0.83 for 25% TPD, 6.65 +/- 0.51 for 50% TPD, and 7.01 +/- 0.96 for APD; these differences were not significantly different. The data in the group II patients demonstrated a mean daily pKt/V of 0.28 +/- 0.03 with 25% TPD, 0.29 +/- 0.05 with 50% TPD, and 0.30 +/- 0.05 for APD. The mean daily pCCr was 6.69 +/- 0.47 for 25% TPD, 8.09 +/- 1.30 for 50% TPD, and 7.63 +/- 1.13 for APD. There were no statistical differences for pKt/V and pCCr within the 24 L group. CONCLUSION: When the duration of therapy and volume of dialysate volume are kept constant, TPD does not result in an improvement in clearances compared with conventional APD, at least with dialysate volumes up to 24 L.

Patient assessment of quality of care in a chronic peritoneal dialysis facility.

The percentage of patients with end-stage renal disease (ESRD) maintained on chronic peritoneal dialysis (CPD) in the United States remains well less than the percentage in several other countries. Furthermore, there has recently been a decline in the percentage of patients with ESRD in the United States undergoing CPD. The reasons for this decline are uncertain, and investigators have implicated problems with the kinetics of peritoneal dialysis, peritonitis and exit-site infections, and psychosocial stresses imposed by the therapy. Few studies, however, have considered the role of the dialysis facility itself and patient perceptions of the facility as contributing to problems with the long-term acceptance of CPD. This study is designed to examine patients' perceptions of the organization and structure of the peritoneal dialysis facility and their interactions with the facility, focusing attention on areas of patient satisfaction and dissatisfaction with the facility. The study was conducted in a large, freestanding peritoneal dialysis program in an urban area that currently treats 140 patients undergoing CPD. Thirty patients were randomly selected to participate in the present study. A structured interview that included open-ended questions was administered and tape-recorded by a trained interviewer not affiliated with the dialysis unit. Patient responses were then reviewed by two investigators, and a taxonomy of patient satisfaction and dissatisfaction was developed, using a modification of the classification proposed by Concato and Feinstein. Patient responses were then categorized according to the taxonomy. The most frequently cited areas of patient satisfaction included the amount of information and instruction provided by the staff (n = 30), personal atmosphere of the facility (n = 30), efficiency of delivery of the dialysis supplies (n = 23), and availability of the primary nurse (n = 18). The importance of the nurse-patient interaction was emphasized by all 30 patients, whereas the physician-patient interaction was cited by only 14 patients. The most frequently cited area of dissatisfaction noted by all 30 patients concerned the dialysis regimen itself. The present study focuses attention on patient perceptions of their CPD facility, identifying areas of satisfaction and dissatisfaction. The analysis is important not only in providing a framework for CPD facilities with which to review their own interactions with CPD patients, but also for identifying those areas that require attention to maintain the long-term viability of CPD therapy.

Incidence of peritonitis in chronic peritoneal dialysis patients infused with intravenous iron dextran.

BACKGROUND: The Dialysis Outcomes Quality Initiative (DOQI) guidelines, published in 1997, emphasize the need for careful monitoring of iron stores and for provision of adequate iron replacement therapy to achieve target goals of hemoglobin concentration in end-stage renal disease (ESRD) patients, especially those treated with recombinant erythropoietin (rHuEPO). Intravenous iron dextran (IVID) therapy, which has long been used in hemodialysis patients, is increasingly being used in chronic peritoneal dialysis (CPD) patients. In 1997, we began using this form of iron therapy for our CPD patients. However, because considerable data exists to show a relationship between iron metabolism and acute infections, we questioned whether IVID infusion placed our patients at greater risk for peritonitis, the leading cause of death and patient drop-out from CPD therapy. OBJECTIVE: To evaluate the relationship between iron and infection, we studied episodes of peritonitis in CPD patients who were infused with IVID. DESIGN: In a retrospective study of adult CPD patients who received IVID during 1998, we investigated the occurrence of peritonitis episodes and the spectrum of causative organisms. Patients with a hemoglobin level of < 12.5 g/dL who also had a ferritin level < 100 ng/mL or a transferrin saturation level < 20% (or both) and who did not respond to oral iron therapy, were administered between 0.5 g and 1.0 g of IVID in an outpatient hospital setting. We calculated the expected and observed number of peritonitis episodes in these patients within 30, 60, and 90 days after infusion of IVID. RESULTS: During the study period, 56 patients received 77 doses of IVID, with 14 patients requiring 2 or more infusions. Of the 77 doses, 71 were given as a 1-g bolus. The IVID was well tolerated by all patients. Within 90 days of IVID administration, 14 patients developed peritonitis: 6 episodes occurred within 30 days, 7 episodes occurred between 31 and 60 days, and 1 episode occurred between 61 and 90 days after the IVID dosing. The peritonitis rate for patients not receiving IVID was 1 episode per 13.7 patient-months. Taking this rate as the "expected" rate, the expected number of episodes of peritonitis for the study population was 5.6 episodes within 30 days, 11.2 episodes within 60 days, and 16.8 episodes within 90 days following IVID administration. The difference between the expected and observed rates of peritonitis in patients who were dosed with IVID was not statistically different. The spectrum of organisms seen in the peritonitis episodes in the study population was not significantly different from that seen in the peritonitis episodes in our CPD unit population. CONCLUSIONS: There is evidence that IVID infusion therapy can improve anemia and reduce rHuEPO requirements in CPD patients, usually without adverse reaction and without exposing patients to an increased risk of peritonitis. More research is needed in the area of potential increased risk of infection in ESRD patients who are (1) infused with large doses of IVID, and (2) iron-overloaded.

Effect of duration of chronic peritoneal dialysis therapy on the development of peritonitis.

OBJECTIVE: Long-term chronic peritoneal dialysis (CPD) therapy has been associated with alterations in peritoneal membrane structure and peritoneal macrophage function. We thus reviewed our experience with the development of peritonitis among patients maintained on CPD therapy for various time periods to determine if the spectrum of organisms, rates of peritonitis, and outcome changed with the duration of CPD therapy. SETTING AND PATIENTS: Patients maintained on CPD therapy in our out-patient unit in New Haven, Connecticut. DESIGN: Retrospective review of the charts of patients maintained on CPD therapy (HomeChoice Cycler or Ultrabag, Baxter, McGaw Park, IL, U.S.A.) between 1 January 1997 and 31 March 1998. These patients were divided into three groups: group 1, patients maintained on CPD therapy < or = 12 months; group 2, patients maintained on CPD therapy for 13-36 months; and group 3, patients maintained on CPD therapy for > or = 37 months. RESULTS: The study included 256 patients: 101 patients in group 1, 110 patients in group 2, and 45 patients in group 3. All groups of patients were similar in age. There were significantly fewer Caucasians and fewer males in group 3 in comparison to groups 1 and 2. The incidence of diabetes mellitus, coronary artery disease, and peripheral vascular disease was significantly lower among patients in group 3 in comparison to groups 1 and 2. There were 155 episodes of peritonitis during the study period for an overall rate of 1 episode in 18.7 patient-months. The overall, gram-positive, and gram-negative rates of peritonitis were not significantly different among the patients in groups 1, 2, and 3. There were more episodes of Staphylococcus aureus peritonitis among patients in group 3 in comparison to group 2 (1 episode in 59.6 vs 1 episode in 280.2 patient-months, respectively). Two weeks after the development of peritonitis, 94.6% of the patients in group 3 continued CPD therapy, while 79.4% of the patients in group 1 continued CPD therapy (p < 0.05). No patient in group 3 transferred to hemodialysis, while 10.3% and 8.2% of the patients in groups 1 and 2 transferred to hemodialysis (p < 0.05). The death rate 2 weeks after the onset of peritonitis was 10.3%, 9.8%, and 5.4% in groups 1, 2, and 3, respectively (p = NS). CONCLUSIONS: Despite the immunological and morphological changes that occur in the peritoneal cavity with increased time on CPD therapy, there was no difference in the overall, gram-positive, or gram-negative rates of peritonitis for patients maintained on CPD therapy for various time periods. Patients in group 3 continued CPD therapy more often than did patients in group 1. Patients in group 3 transferred to hemodialysis less often than did the remaining patients in the study period. The incidence of death was not significantly different for the three groups of patients.

Bilateral renal infarction secondary to paradoxical embolism.

Paradoxical embolism is an uncommon but increasingly reported cause of arterial embolic events. Involvement of the kidney is rarely reported. Autopsy studies suggest, however, that embolic renal infarction is underdiagnosed antemortem. We report a case of bilateral, main renal artery occlusion and acute renal failure secondary to paradoxical embolism. Clinical and laboratory data at presentation were not suggestive of renal infarction. Support for the diagnosis of paradoxical embolism, which most commonly occurs across a patent foramen ovale, was made by contrast echocardiography, which provides a sensitive method for detecting right-to-left intracardiac shunts. The often subtle presentation of renal infarction suggests patients with peripheral or central arterial embolic events should be carefully observed for occult renal involvement. Contrast echocardiography should be performed when renal infarction occurs without a clear embolic source to evaluate for paradoxical embolism.

Value of scintigraphy in chronic peritoneal dialysis patients.

BACKGROUND: A variety of factors can adversely impact chronic peritoneal dialysis (CPD) as an effective renal replacement therapy for patients with end-stage renal disease. These factors include peritonitis, poor clearances, loss of ultrafiltration, and a variety of anatomic problems, such as hernias, peritoneal fluid leaks, loculations, and catheter-related problems caused by omental blockage. This study reviews our experience with peritoneal scintigraphy for the evaluation of some of these difficulties. METHODS: From 1991 to 1996, 50 peritoneal scintigraphy scans were obtained in 48 CPD patients. Indications for scintigraphy were evaluated, and the patients were placed into four groups: group I, abdominal wall swelling; group II, inguinal or genital swelling; group III, pleural fluid; and group IV, poor drainage and/or poor ultrafiltration. A peritoneal scintigraphy protocol was established and the radiotracer isotope that was used was 2.0 mCi of 99mtechnetium sulfur colloid placed in two liters of 2.5% dextrose peritoneal dialysis solution. RESULTS: Ten scans were obtained to study abdominal wall swelling, with seven scans demonstrating leaks; six of these episodes improved with low-volume exchanges. Twenty scans were obtained to evaluate inguinal or genital swelling, and 10 of these had scintigraphic evidence for an inguinal hernia leak (9 of these were surgically corrected). One of four scans obtained to evaluate a pleural fluid collection demonstrated a peritoneal-pleural leak that corrected with a temporary discontinuation of CPD. Sixteen scans were obtained to assess poor drainage and/or ultrafiltration. Five of these scans demonstrated peritoneal location, and all of these patients required transfer to hemodialysis. The other 11 scans were normal; four patients underwent omentectomies, allowing three patients to continue with CPD. CONCLUSION: Peritoneal scintigraphy is useful in the evaluation and assessment of CPD patients who develop anatomical problems (such as anterior abdominal, pleural-peritoneal, inguinal, and genital leaks) and problems with ultrafiltration and/or drainage.

Evaluating patients with renal failure for renal artery stenosis with gadolinium-enhanced magnetic resonance angiography.

The incidence and prevalence of end-stage renal disease (ESRD) continues to increase, especially in the elderly population. The role of renovascular disease in contributing to ESRD is still not well defined. The objective of this study was to determine the utility of gadolinium (Gd)-enhanced magnetic resonance angiography (MRA) in evaluating elderly patients with renal insufficiency for renal artery stenosis (RAS). A 7-month prospective study conducted in a tertiary referral center evaluated 40 consecutive patients with progressive renal insufficiency (18 men and 22 women; mean age, 70 +/- 5.6 [standard deviation] years) and high clinical suspicion for renovascular disease with Gd-enhanced MRA. Digital subtraction angiography (DSA) was obtained in only those patients with significant RAS detected by MRA. Twelve patients had significant RAS. Six of these patients had percutaneous transluminal renal angioplasty (PTRA), five patients had renal artery bypass surgery, and one patient had a stent placed after PTRA. Seventy-eight renal arteries were satisfactorily evaluated by MRA. Twenty-two renal arteries were evaluated by both MRA and DSA. Of the 12 significant stenoses detected by the MRA, 11 were confirmed by DSA and 1 was confirmed at the time of surgical revascularization. It is concluded that Gd-enhanced MRA is a useful test for the evaluation of RAS in patients with compromised renal function.

Tidal peritoneal dialysis to achieve comfort in chronic peritoneal dialysis patients.

Patients with end-stage renal disease on chronic peritoneal dialysis (CPD) can usually tolerate continuous ambulatory peritoneal dialysis (CAPD) or continuous cycling peritoneal dialysis (CCPD) without abdominal discomfort or pain. In some patients, pain or discomfort occurs with complete drain of the peritoneal dialysis solution or upon initiation of dialysis filling when the peritoneal cavity is empty. We report on the use of tidal peritoneal dialysis (TPD) as a modality to alleviate this pain. Of 136 patients in our CPD unit, 18 (13%) were complaining of pain with complete drain or upon instillation of PD fluid. All were placed on TPD after other causes for abdominal pain were excluded. Six patients were placed on 25% TPD, and 12 patients on 50% TPD. The mean Kt/V of the patients on TPD was 2.46 +/- 0.68. With TPD, all patients had complete relief of abdominal discomfort. Patients who develop abdominal pain with complete drain or fill when the abdominal cavity is empty would benefit from TPD and be able to continue with CPD.