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B F Prowant

Publications and source records attributed to B F Prowant.

At least 19 recordsLinked to original sources

Six-year experience with swan neck catheters.

From the beginning of our continuous ambulatory peritoneal dialysis (CAPD) program in January 1977 until June 1985, we used Tenckhoff and Toronto Western Hospital catheters. Throughout these years catheter survival probabilities of about 30% at three years persisted unchanged and were similar to survival probabilities reported by the National CAPD Registry special survey for these catheters. The first improvement in catheter results regarding leaks was noted after the adoption of lateral catheter insertion. Malfunction was less using swan neck prototypes from August 1985 to April 1986. The latter catheters were made of 80 degrees arc angle tubing between 8.5 cm spaced cuffs and were inserted in a reversed U-shape tunnel with the incision at the top of the tunnel. The use of these catheters was abandoned because of high cuff extrusion and exit infection rates. The next generation of swan neck catheters, the swan neck Missouri 2 and 3 catheters with straight intraperitoneal segments, improved the results dramatically. These catheters were made of 180 degrees arc angle tubing between 5 or 3 cm spaced cuffs. The estimated survival probability of 61% at three years more than doubled compared to previously used catheters. Recently we modified the intraperitoneal segment of the catheters, replacing the straight segment with a coiled one. These modified catheters, the swan neck Missouri coiled catheters, have been used exclusively since February 1990. In addition to an acceptable survival probability of 88% at one year, there are two major advantages of these catheters, the same as for other coiled catheters: elimination of infusion pain due to a jet effect and pain related to straight catheter tip pressure on the peritoneum experienced by some patients.

Bacterial Infections

The peritoneal equilibration test: a nursing discussion.

The peritoneal equilibration test is used to assess peritoneal membrane permeability. Results provide a reliable estimate of peritoneal clearances and ultrafiltration rates. This information can be used to make decisions about the preferred dialysis prescription. Repeat tests may be used to evaluate clinical changes. The first part of this two-article series will discuss the clinical interpretation of findings and three case studies. The second article will describe the procedure.

Cell Membrane Permeability

How to do a peritoneal equilibration test.

This article, part 2 of a 2-part series, describes the process and procedures used to perform a peritoneal equilibration test. Data from the test may be used to assess the peritoneal membrane permeability. Knowledge of peritoneal membrane permeability may be useful in selecting a treatment regimen and in determining the appropriate dialysis prescription.

Cell Membrane Permeability

What effect does glucose have on measured creatinine in the peritoneal equilibration test?

Very high glucose concentrations falsely elevate measured creatinine. An appropriate correction factor may be applied to obtain an accurate creatinine value; however, the glucose interference is of a low magnitude in most dialysate samples at a 4-hour dwell time. Clinical interpretation of the peritoneal equilibration test using uncorrected creatinine values to determine the dialysate-to-plasma ratio at 4 hours is associated with minimal error.

Colorimetry

Tidal peritoneal dialysis with racemic or L-lactate solutions.

UNLABELLED: To see if rapid lactate absorption on tidal peritoneal dialysis (TPD) would overwhelm D-lactate metabolism using racemic lactate and/or L-lactate metabolism using all L-lactate, five patients underwent 8-h TPD treatments with racemic lactate solution one day and with L-lactate another. Lactate concentrations (total) were 40 mmole/L, flow rates 27.3 L/8 h, tidal and reservoir volumes each 1.5L, tidal cycles 24-26 min, and net ultrafiltration per tidal cycle 70 to 99 mL. RESULTS: Mean absorptions of D and L-lactate were 24.2 and 25.1%, respectively, compared to glucose at 14.6%. Urea clearances averaged 21.4 mL/min. Mean blood D-lactates at baseline were 0.6 +/- 0.5 SD mmole/L and after 8 h of TPD were 0.6 +/- 0.4 and 0.7 +/- 0.3 using L-lactate and racemic solutions, respectively; similar values for L-lactate were 1.2 +/- 0.3 at baseline and 1.2 +/- 0.3 and 1.2 +/- 0.5 after 8 h with L-lactate and racemic solutions. delta blood pH values were + 0.02 +/- 0.01 and + 0.04 +/- 0.03, while delta bicarbonate values were + 1.7 +/- 0.9 and + 0.7 +/- 1.0 for the all L and racemic studies, respectively. The total mmoles of L-lactate absorbed per 8 h of TPD with all L solution (greater than 300 mmoles) are greater than ever reported for peritoneal dialysis, but did not increase blood lactate levels. It would seem that either type of solution is suitable for TPD. Absorptions and metabolic rates are similar for L-Lactate and D-Lactate.

Adult

Hematocrit and residual renal creatinine clearance in patients undergoing continuous ambulatory peritoneal dialysis (CAPD).

In a recent report, the relationship between renal creatinine clearance and hematocrit in patients with renal creatinine clearances, ranging from 55 to 8 mL per min. per 1.73 square meters of body surface area, was analyzed. The authors of this study have performed a cross-sectional analysis of the relationship of hematocrit to residual renal creatinine clearance in patients on continuous ambulatory peritoneal dialysis (CAPD). The authors of this study wanted to examine whether or not these hematocrits fall within extrapolations of the published 95% confidence limits for males and females with renal failure prior to end-stage renal disease and dialytic intervention. Authors also compared regression intercepts at residual creatinine clearances of 0. Most of the CAPD patients had hematocrits within the upper half or above the extrapolated 95% confidence limits for the predialysis population. Within the CAPD population, there were no significant correlations of hematocrit with residual creatinine clearance at these lower ranges. The degree of scatter in the CAPD population for hematocrit values was similar to that in the predialysis population. Residual creatinine clearance appears to be a crude index of the increasing severity of multiple factors that may contribute to the anemia. CAPD appears to maintain or improve hematocrit as renal mass and function decline.

Anemia

Effectiveness of a phosphorous educational program for dialysis patients.

Fifty-four percent of all dialysis patients followed by a single center had elevated serum phosphorus levels on more than 25% of all measurements. A phosphorus patient education program was developed and implemented and knowledge was measured with a pretest and posttest. The continuous ambulatory peritoneal dialysis group had a significant increase in knowledge and a minor, but statistically significant, decrease in serum phosphorus after participating in the education program. In contrast, center hemodialysis patients did not demonstrate a significant increase in knowledge or decrease in serum phosphorus. These different outcomes could not be attributed to specific differences between the two groups. Serum phosphorus control is a complex process, and this education program did not result in a clinically significant improvement in serum phosphorus levels.

Adolescent

Peritoneal dialysis transfer set change procedures study.

The purpose of this in vitro study was to evaluate the effectiveness of continuous ambulatory peritoneal dialysis (CAPD) procedures. Four procedures to disinfect the catheter adapter/transfer set connection were compared in vitro using a mock sterile CAPD system.

Disinfection

A comparison of inpatient and outpatient Medicare allowable charges for continuous ambulatory peritoneal and center hemodialysis patients: a single-center study.

Medicare allowable charges were compared between 21 continuous ambulatory peritoneal dialysis (CAPD) and 25 center hemodialysis (CHD) patients for the 12-month period from Sept 1982 through Aug 1983 to determine if savings from CAPD therapy were offset by higher hospitalization charges. All adult patients on a single therapy for the 12-month period who were not dialyzed or hospitalized at other institutions were included. The CAPD and CHD patient groups did not differ significantly by age, sex, or incidence of systemic disease. However, the CHD group had significantly more black patients. The primary renal disease, the incidence of diabetes mellitus, and other systemic diseases did not differ between the groups. The number of hospital admissions was similar between the two groups. However, the CHD patients tended to have a higher number of hospital days than the CAPD group (17.5 v 12.4). Although the total hospital charges tended to be higher for CHD ($16,145) than CAPD patients ($9,872), this difference was not significant. Outpatient dialysis charges were significantly less expensive for CAPD ($16,470) than CHD ($28,233). Emergency department charges were also significantly less for the CAPD group. Charges for patients with and without systemic disease were analyzed separately. In both subgroups, all charges were less for CAPD therapy; however, this difference was significant only for outpatient dialysis charges. Total charges for the 12-month period were significantly less for the CAPD group ($26,453) than for CHD ($45,586). This demonstrates that hospitalization charges did not offset the savings of home dialysis in these patients.

Ambulatory Care Facilities

Intraabdominal pressures during natural activities in patients treated with continuous ambulatory peritoneal dialysis.

Intraabdominal pressures were measured during natural activities in 6 men, age 24-62 years, treated with continuous ambulatory peritoneal dialysis. The pressures were measured with a pressure transducer secured at the level of the umbilicus in the supine, sitting, and upright positions with 0-3 liters intraperitoneal fluid during talking, coughing, straining, changing position, walking, jogging, exercycling, jumping and weight lifting. Coughing and straining generated the highest intraabdominal pressures in every position. The pressures with weight lifting were proportional to the magnitude of the weight lifted up to 50 lbs, but were lower than those during coughing and straining. The pressures were generally higher with greater intraabdominal fluid volumes, especially with jumping and coughing. Exercycling was associated with lower intraabdominal pressure than was jogging, and the pressures were only minimally influenced by intraperitoneal fluid volumes. The results of this study can be used as a guide in establishing preventive measures in patients with intraperitoneal fluid to decrease complication rates related to raised intraabdominal pressures such as dialysate leaks, hernias and hemorrhoids.

Abdomen

Continuous ambulatory peritoneal dialysis for psoriasis. A report of four cases.

Four patients with psoriasis were treated with continuous ambulatory peritoneal dialysis (CAPD). Two were being treated for renal failure; the other two had normal renal function and were being treated exclusively for psoriasis. With CAPD at a rate of three to four exchanges per day, the psoriasis cleared completely in the two patients with renal failure and improved in the other two. In the patients without renal failure, low-flow peritoneal dialysis (one exchange per day) seemed to be of some value in maintaining remission but was ineffective in treating more active disease. Long-term therapy (greater than or equal to 12 weeks) with three or four daily exchanges may be needed for initial complete remission, and continuous treatment may be needed to prevent relapse. Thus, CAPD shows promise for the study of psoriasis and may be a last-resort treatment for severe, disabling cases.

Adult

Peritoneal access and related complications in continuous ambulatory peritoneal dialysis.

Over a four-year period, 50 patients underwent continuous ambulatory peritoneal dialysis. After 24 months, 48 percent of the patients continued to receive continuous ambulatory peritoneal dialysis treatment (including those who underwent continuous ambulatory peritoneal dialysis with bottled solutions from 1977 to 1978). Using solutions in plastic bags, 63 percent of patients continued to undergo continuous ambulatory peritoneal dialysis after 24 months. The mortality rate at 24 months was 23 percent overall and 15 percent for those using plastic bags. There was an overall average of 2.4 episodes of peritonitis a year per patient and 1.3 episodes a year per patient from 1979 through 1980, when only the technique with plastic bags was used. The number of days a patient was hospitalized averaged 48 per year, and 37 days per year in 1979 and 1980. Fifty-five percent of catheters remained functional at 24 months. Other complications included 15 hernias, 15 skin and tunnel infections, 12 leaks, and five cuff extrusions. Improved catheters and further reductions in the incidence of peritonitis will most likely result in a decreased number of patients who withdraw from continuous ambulatory peritoneal dialysis therapy.

Adolescent

High volume, low frequency continuous ambulatory peritoneal dialysis.

Intra-abdominal pressure (IAP), forced vital capacity (FVC), and forced expiratory volume at 1 sec (FEV1) were measured in 18 stable continuous ambulatory peritoneal dialysis (CAPD) patients maintained on 2-liter exchanges, in the supine, sitting, and upright positions after infusing dialysis solutions in 0.5-liter increments up to 4 liters as tolerated. Thereafter, five patients did not increase to 3-liter volumes (RUT-0), four used 3-liter volumes occasionally (RUT-1), and nine chose 3-liter volumes for routine dialysis (RUT-2). IAP was similar in all groups and dependent on the intraperitoneal volume (IPV). The mean IAP increased 2.0, 2.7, and 2.8 cm H2O/liter of IPV in the supine, upright, and sitting positions, respectively. The patients of the RUT-0 group had dramatic deterioration (up to 42%) of FVC and FEV1 in the supine position with IPV above 2 liters. The patients with the greatest deterioration of pulmonary functions could not continue the measurements above 3 liters of IPV. Two of these patients were switched to 1-liter overnight exchanges. Even in patients who tolerated up to 4 liters, FVC and FEV1 decreased significantly in the supine and sitting positions, with IPV greater than 3 or 4 liters, respectively. In the upright position, the values did not decrease significantly below those with the empty abdomen up to 4.6 liters of IPV. Each liter of IPV increased the abdominal girth by 2.1 cm. Exchange volume and frequency should be individualized. In our studies, 50% of the patients could increase daily dialysate volume from 8 to 9 liters while decreasing daily exchanges from 4 to 3.

Abdomen