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B F Prowant

Publications and source records attributed to B F Prowant.

At least 19 recordsLinked to original sources
PubMed1996

Four-year experience with swan neck presternal peritoneal dialysis catheter.

The swan neck presternal catheter is composed of two flexible (silicon rubber) tubes joined by a titanium connector at the time of implantation. The exit site is located in the presternal or parasternal area. The catheter located on the chest was designed to reduce the incidence of exit site infections compared with peritoneal dialysis catheters with abdominal exit sites. From August 1991 to May 1995, 24 swan neck presternal catheters have been implanted in 24 patients for the following reasons: obesity nine patients, ostomies three patients, a suprapubic catheter one patient, previous problems with abdominal catheters two patients, desire to use a bathtub five patients, need to use a whirlpool one patient, need to wear sweatpants with an elastic waistband one patient, and body image two patients. In the same period, 47 abdominal swan neck catheters were implanted in 44 patients who preferred catheters with the exit on the abdomen. Presternal catheters tended to perform better regarding exit and tunnel infections, even though they were implanted in several patients in whom regular catheters with the exit on the abdomen would be difficult or impossible to implant. Two-year survival probability of presternal catheters was 0.88 +/- 0.14 (+/- SE). Recurrent/refractory peritonitis was the only reason of catheter failure. The differences in results between presternal and abdominal catheters were statistically insignificant; only the use of antibiotics to treat exit site infection was significantly higher with abdominal catheters. Patient acceptance of the exit position was good; at least seven patients preferred presternal catheter for psychological or body image reasons. We conclude that the swan neck presternal catheters provide excellent results comparable to those achieved with swan neck abdominal catheters. The catheter seems suitable for any patient commencing peritoneal dialysis and is particularly useful in extremely obese patients (body mass index > 40 kg/m2) and those with ostomies. The catheter exit location in the chest may be preferred by some patients, both men and women, for psychological or body image reasons. No specific contraindications to the presternal catheter implantation have been identified.

Abdomen↗
PubMed1995

Predicted and measured daily creatinine production in CAPD: identifying noncompliance.

OBJECTIVE: To evaluate the ratio of measured creatinine (Cr) production to predicted creatinine production as an index of noncompliance in patients on continuous ambulatory peritoneal dialysis (CAPD). DESIGN: A cross-sectional analysis. PATIENTS: One hundred and twenty-one patients on CAPD. MEASUREMENTS: We have calculated Cr production from measured Cr outputs in 24-hour collections of urine and dialysate. Predicted Cr productions were calculated from standard tables. Weekly KT/V urea and weekly Cr clearances were determined from the same 24-hour urine and dialysate collections. Lean body mass (LBM) was calculated from the Cr production. Serum albumin concentration was measured. RESULTS: The ratio of measured/predicted Cr production correlated positively and significantly with weekly KT/V urea, the protein equivalent of nitrogen appearance (PNA), weekly Cr clearance, and LBM. There was a decline in serum albumin concentration at ratios greater than 1.24, supporting the opinions of previous authors who have suggested that ratios greater than 1.24 are highly suggestive of noncompliance with the dialysis prescription. Defining noncompliance as a ratio greater than 1.24 implied that at least 5% of the female and 17% of the male patients were noncompliant. CONCLUSIONS: Declining serum albumin concentrations at higher ratios of measured/predicted Cr production support the opinion that this is an index of noncompliance. However, not all noncompliant patients necessarily have a ratio greater than 1.24. Weekly KT/V urea, weekly Ccr and LBM are all artifactually increased by "washout effects" if all exchanges are done only or mainly on the collection day.

Body Mass Index↗
PubMed1995

Preliminary evaluation of silver-coated peritoneal catheters in rats.

Silver is known to have powerful antibacterial properties against a variety of micro-organisms and has a low toxicity and a favorable biocompatibility profile. This study was designed to evaluate the effectiveness of silver-coated catheters in preventing early exit-site infection and to assess tunnel morphology. Seven male Sprague-Dawley rats underwent simultaneous implantation of two double-cuffed, silver-coated silicone rubber and standard silicone rubber catheters. Weekly observations and photographs documented exit-site characteristics. The animals were sacrificed and catheters removed and processed for histopathology of the external tunnel at 5 weeks. Exit sites of silver-coated catheters tended to have less inflammation and infection and healed better than those of uncoated catheters; however, these data did not achieve significance using the Wilcoxon signed-rank test. Sections of the external tunnel of well-healing exit sites showed an epithelialized tract with granulation tissue near the cuff and significant invasion of the external cuff by collagen with a mild neutrophilic inflammatory response. In contrast, the histology of the external tunnel of infected exists revealed exudate overlying inflammatory granulation tissue and a variable degree of fibrosis of the cuff. When the exit sites appeared similar, no significant histopathological differences in sinus tract and cuff morphology were noted with either silver or standard catheters. In conclusion, these findings suggest that silver coating of catheters may decrease the incidence of early exit-site infections and allow better ingrowth of the catheter.

Animals↗
PubMed1994

Comparison of different measurements of lean body mass in normal individuals and in chronic peritoneal dialysis patients.

To evaluate different methods of measuring lean body mass (LBM) in chronic peritoneal dialysis (CPD) patients, we first made comparisons in seven normal subjects. Seven methods (total body potassium [TBK] counting, bioelectrical impedance with calculations according to Segal and Deurenberg, near-infrared interactance with and without exercise level included as a variable, anthropometric measurements, and creatinine kinetics) were compared with the standard method of underwater weighing (UW) for measuring LBM. Significant correlations with LBM measured by UW (r > 0.938) were found with LBM measured by all other methods. Compared with UW, the best result in normals was found with TBK as it had high r values, small y-intercepts, and slopes of regression lines close to unity in both measurements of LBM and %LBM; in addition, fat-free mass index by TBK best approximated that by UW and TBK had the lowest mean prediction error with UW. In 11 patients on CPD, LBM was measured by all the above methods except UW. Significant correlations of all methods with LBM measured by TBK used as the reference standard were noted (all r > 0.76) in the CPD population. The LBM measured by creatinine kinetics correlated best (by kilograms or percentage of body weight [%BW]) with LBM from TBK compared with the other methods in which values tended to be higher. The fat-free mass index by creatinine output was nearest to the fat-free mass index by TBK. The root mean square prediction error was lowest between LBM by creatinine output and that by TBK. The findings support the concept of measuring creatinine outputs in CPD patients for estimates of LBM as an index of nutritional status as well as for creatinine clearances as an index of adequacy. Total body potassium and creatinine output measurements of LBM reflect the LBM at normal body fluid volumes ("dry weight") and may be better indices of nutrition in dialysis patients than the other techniques, which include excess fluid in the LBM.

Adult↗
PubMed1994

Changes in the peritoneal equilibration test in selected chronic peritoneal dialysis patients.

Fifty-five patients on chronic peritoneal dialysis with two or more peritoneal equilibration tests (PET) performed between 1983 and 1992 with a mean interval of 21.9 +/- 22.7 months were studied retrospectively. Repeated PET were performed when transport changes were suspected rather than routinely. According to the initial PET, there were 16 high (HI), 17 high-average (HA), 15 low-average (LA), and 7 low (LO) transporters. There was a significant decrease in the mean creatinine dialysate to plasma ratio (D/P creatinine) in the HI transporters and an increase in the LA and LO transporters. The mean dialysate to instilled glucose ratio (D/Do) significantly increased in the HI transporters. The change in both the D/P creatinine and the D/Do of an individual strongly and inversely correlated to their respective initial values. The change in D/P creatinine and D/Do were significantly and inversely correlated to each other, indicating an actual transport change. No correlation was found between the change in transport with peritonitis episodes or frequencies. The centripetal [corrected] change of transport toward average described here may explain why low clearances or low ultrafiltration rates due to rapid transport are infrequent causes of peritoneal dialysis technique failure, and why patients who have been dialyzed for a long period are usually HA transporters.

Biological Transport, Active↗
PubMed1994

Computer interaction: catheters.

A computer interaction session conducted during the 14th Annual Peritoneal Dialysis Conference in Orlando, Florida, on January 24, 1994, revealed the preferences and practices of 650-690 respondents voting on questions related to peritoneal catheters. Compared to the surveys conducted in 1987 and 1989, the most striking change was an increase in the use of catheters with the bent intramural segment, particularly the Swan neck catheter, and an increase in the use of catheters with the coiled intraperitoneal segment. The Tenckhoff catheter continued to be the most popular, although its use was decreasing. The remaining catheters were used in small numbers. The vast majority of nephrologists remain convinced of the superiority of double cuff catheters over single cuff ones, and the use of the former continued to exceed 70%. Essentially no change occurred in the method of catheter placement; surgical dissection (72.7%) remained the most popular implantation method. Surgeons were primarily responsible for catheter implantations (87.4% of votes). The use of prophylactic antibiotics prior to catheter implantation seems to be increasing. The majority of respondents did not consider a Staphylococcus aureus nasal carrier status as important in the development of catheter-related infections, as indicated by the small number of centers where routine culture of nares was performed. The majority of institutions delayed ambulatory peritoneal dialysis after catheter implantation, but ambulatory peritoneal dialysis was started in some centers (5.7% of votes) in the immediate postimplantation period.

Attitude of Health Personnel↗
PubMed1994

Computer interaction: demographics, adequacy, and nutrition.

Over 700 people attending the Opening Session of the Fourteenth Annual Peritoneal Dialysis Conference participated in the computer interaction exercise as keyboard responders. Responders were 50.5% nurses and 40.4% physicians. Of these, 70.4% were from North America and 19.6% were from Europe. Only 9.5% had been involved in chronic peritoneal dialysis for less than one year. Over half (56%) worked in programs with more than 30 chronic peritoneal dialysis patients. Their own personal choice of dialysis therapy was a form of chronic peritoneal dialysis in 82%. Serum albumin concentration was indicated as the main monitor of nutritional status by 79.1%. Dietary protein intake ranging from 1-1.2 was considered the preferred goal by 84.4% of responders, even though the majority of chronic peritoneal dialysis patients probably do not achieve dietary protein intake in this range. A minimum weekly KT/V urea of 1.7 was chosen as a minimum target by 53.4%. An increase in exchange volume was the most frequently chosen approach to the large, anuric, low-peritoneal transporter. Numerous other questions dealing with adequacy and nutrition were posed to the audience, and the findings are summarized herein.

Attitude of Health Personnel↗
PubMed1994

Disaster preparedness: is your unit really ready?

This article brings attention to the need for disaster preparedness by individual dialysis facilities. It is recommended that each facility develop a specific plan for each type of disaster that might occur in the particular geographic location. It is also recommended that the community's disaster plan(s) be reviewed and incorporated in the planning process. This article addresses all aspects related to a natural disaster, including planning, drills, basic services, personnel, and the aftermath. Adequate preparation may lessen the destruction and negative consequences of a natural disaster.

Clinical Protocols↗
PubMed1993

Home visit effectiveness for peritoneal dialysis patients.

Medicare regulations require follow-up home visits to home dialysis patients, yet routine home visits require a lot of personnel time. The effectiveness of home visits was evaluated by a nurse, dietitian and social worker using a questionnaire. Thirty-six patients were evaluated during an 18-month period. Collectively the team documented an average of 10 pertinent observations per visit and made an average of 4 recommendations for change. Staff members gained new information about the patient as indicated by the fact that they changed their rankings on 5 of 15 parameters following the home visit. The home visit policy that recommended an annual home visit was revised to recommend a single home visit for each new peritoneal dialysis patient. Further visits are performed only if significant problems are identified.

Adult↗
PubMed1993

Peritoneal dialysis catheter exit-site care: results of an international survey.

A survey was developed to determine the prevalence of specific components of postoperative and chronic peritoneal catheter exit-site care procedures. Surveys were mailed to approximately 1800 participants of the 1991 Peritoneal Dialysis Conference; 585 surveys (80.6% from the United States and 96% from adult units) were analyzed. The most frequent components of postoperative exit-site care were the use of prophylactic antibiotics, daily dressing changes, procedures limited to specially trained staff, use of sterile technique, povidone iodine and hydrogen peroxide as cleansing agents, and gauze dressings. The most frequent components of chronic exit-site care procedures were daily care done with shower or bathing, antibacterial or pure soap for cleansing, hydrogen peroxide only as needed, catheter stabilization, dressings optional, and gauze dressings when used. Twice daily exit care, change in cleansing agent, and topical antibiotics were recommended for inflamed or infected exit sites. There were significant differences between the United States and other locations, particularly in the type of cleansing agent, use of hydrogen peroxide, and use of dressings for chronic care. Pediatric programs (all located in the United States or Canada) differed somewhat from adult programs in North America. Pediatric patients and their families were significantly more likely to be trained to do postoperative dressing changes and significantly less likely to perform exit-site care at the time of showering or bathing.

Adult↗
PubMed1992

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↗
PubMed1991

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↗
PubMed1991

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↗