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S Vas

Publications and source records attributed to S Vas.

At least 19 recordsLinked to original sources

Structural changes in silicon rubber peritoneal dialysis catheters in patients using mupirocin at the exit site.

Structural damage to polyurethane PD (peritoneal dialysis) catheters in patients using mupirocin ointment is widely appreciated, but damage to silicon rubber PD catheters is less well described. Ten catheters (6.6%) out of 152 were found to have structural alterations such as opacification, ballooning, thinning, and rupture. The duration of PD in these 10 patients ranged from 23 months to 80 months (mean duration 51.1 months). The frequency of mupirocin application varied from daily (2 cases) to 2-3 times per week (7 cases). In eight catheters opacification occurred at the exit site whereas one catheter showed opacification midway between the exit site and the titanium adaptor. One catheter showed opacification, ballooning, and thinning at the exit site ruptured in the form of two slit-like openings. In conclusion, various structural changes such as opacification, ballooning or thinning were seen in 6.6% of silicon rubber PD catheters in patients using mupirocin at the exit site. Although the mechanism remains elusive, mupirocin or the antiseptic solution alone or in combination may be contributory. We believe that this is an under-reported complication and encourage other health care givers to incorporate a search for such changes during clinic visits.

Adult↗

Infections in patients undergoing peritoneal dialysis.

Considering experience acquired in the past years, it seems as though physicians have reached a plateau in the frequency of peritonitis. A peritonitis rate of 1 every 2 patient years may be acceptable. Further reduction of this peritonitis rate will require inordinately large efforts on all fronts. One will have to consider what are the acceptable costs and risks of peritonitis in patients on peritoneal dialysis. New developments in catheter technology, improved connections, better understanding of patient selection and training programs, improved diagnostic and therapeutic methods in the management of peritonitis, and understanding of the infectious and immune processes are eagerly awaited developments.

Anti-Bacterial Agents↗

Excessive weight gain during peritoneal dialysis.

The authors carried out a retrospective chart review in 114 patients treated for at least two years at the Toronto Western Hospital Peritoneal Dialysis Unit and identified eight, who gained an "excessive" amount of weight equal to or greater than 10 kg of their initial weight. These patients had gained an average of 13.1 kg over the preceding two years. They are mostly males and their average age is 51 years. They are well-nourished normotenseive nondiabetics with mostly normal cardiac function. They are adequately dialyzed (per KT/V urea), have little residual renal function and typically have peritoneal membranes characterized by high average transport. According to BIA analysis, this weight gain was likely due to an increase in fat mass accompanied by a trend toward decreasing body-cell mass. This weight gain may be due to increased caloric intake secondary to dialysate glucose absorption in the setting of high average (peritoneal membrane) transport. Such excessive weight gain also may occur if these patients have polymorphism of the UCP-2 gene, which can alter metabolic rate.

Adult↗

Nocturnal hemodialysis: three-year experience.

There is evidence that high frequency, as well as long duration, hemodialysis provides better clinical outcomes. We developed nocturnal hemodialysis, a new innovative form of renal replacement therapy, which is performed six to seven nights per week for 8 to 10 h during sleep at home. Blood flow was set at 300 ml/min and dialysate flow at 100 ml/min. An internal jugular catheter was used as the vascular access. Special precautions were taken to prevent accidental disconnection during sleep, as well as air embolization. Dialysis functions from the patient's home were monitored continuously via a modem at the nocturnal hemodialysis center. Twelve patients have completed training and have been successfully performing nocturnal hemodialysis for up to 34 mo. This study represents 170 patient months of experience accumulated over 3 yr. There was hemodynamic stability and significant subjective improvement in patient well being. Nightly Kt/V was 0.99. Weekly removal of phosphate was twice as high and beta2 microglobulin 4 times as high as conventional hemodialysis. All patients have discontinued their phosphate binders and have increased dietary phosphate and protein intake. BP control was achieved with fewer medications. Dialyzer reuse has decreased the operating costs to the level of the other form of home dialysis. Complications were infrequent and were related primarily to the dialysis access. Nocturnal hemodialysis represents the most efficient form of dialysis at low cost and should be considered as an option for patients who can be trained for home hemodialysis.

Adult↗

Slow nocturnal home hemodialysis at the Wellesley Hospital.

To alleviate the overcrowding of in-center hemodialysis (HD) facilities, we have developed slow nocturnal home hemodialysis (SNHHD), an innovative form of renal replacement therapy. SNHHD is performed 5 to 7 nights/week for 8 hours, during sleep, with a blood flow of 300 mL/min and a dialysate flow of 100 mL/min. The vascular access is by means of the Uldall-Cook catheter, which allows for easy patient access with low infection rates. Special precautions were taken to prevent accidental disconnection during sleep. Dialysis functions were monitored via a modem from the patient's home to the SNHHD center and have proven valuable in increasing patient confidence. The removal of urea, phosphate, and B2 microglobulin (B2M) during 1 week of SNHHD greatly exceeds that of thrice weekly conventional HD. Five patients have completed training and have been successfully performing SNHHD for 6 to 16 months. All patients have discontinued phosphate binders and increased dietary phosphate intake. Four out of five patients report sleeping soundly and experience greatly increased energy and stamina. Repeated in situ reuse of the dialyzer and the blood lines will reduce the patients work and make SNHHD a very inexpensive modality.

Adult↗

Slow nocturnal home hemodialysis (SNHHD)--one year later.

High costs and overcrowding of dialysis centres are leading to a global crisis in health care provision. We are developing slow nocturnal home hemodialysis (SNHHD) in which patients dialyze for eight to 10 hours during sleep five to seven nights per week. Vascular access is by means of the Cook silastic jugular catheter. Special precautions are taken to prevent accidental disconnection and air embolism. Dialysis functions are remotely monitored on computer via a modem by trained staff. Five patients have completed five to seven weeks of training and have been successfully performing SNHHD single-handedly (three out of five patients live alone) for 14, 14, 11, 10 and four months respectively. All have discontinued their phosphate binders and increased dietary phosphate intake. Compared with conventional hemodialysis (CHD) results, average pre-dialysis urea and creatinine levels are remarkably reduced to 9.6 mmol/l and 486 umol/l respectively. The average cumulative weekly Kt/V for CHD is 5.0 as compared to 7.7 while on SNHHD. Four out of five patients report sleeping soundly and experience greatly increased energy and stamina. Their days are entirely free. Repeated in-situ re-use of the dialyzer and blood lines will reduce the patient's work and make SNHHD a very inexpensive modality. SNHHD appears to be a widely applicable treatment with many advantages to both the patient and the health care system.

Adult↗

Interferon alfa treatment of chronic hepatitis B: randomized trial in a predominantly homosexual male population.

BACKGROUND/AIMS: It has been suggested that human immunodeficiency virus (HIV) coinfection and male homosexuality predict poor response to interferon alfa therapy of chronic hepatitis B. The aim of this study was to examine the effect of HIV coinfection on the response of chronic hepatitis B virus (HBV) infection to interferon alfa therapy in a predominantly homosexual male population. METHODS: Fifty patients (82% male homosexuals, 50% HIV positive) with evidence of chronic HBV infection were randomized, stratified by HIV status, to undergo either treatment with interferon alfa (10 MU/m2 three times weekly for 12 weeks) or no treatment. Response was predefined as loss of serum HBV DNA, loss of hepatitis B e antigen, and the appearance of antibody to hepatitis B e antigen. HIV status and the interferon alfa-associated enzyme, 2',5'-oligoadenylate synthetase, were evaluated as potential predictors of response to therapy. RESULTS: Six treated patients responded with development of antibodies to hepatitis B e antigen (P < 0.05). HIV-positive patients were about one-fifth as likely to respond to interferon alfa therapy (relative risk, 0.22; 95% confidence interval, 0.03-1.78). Pretreatment alanine aminotransferase levels were significantly higher in responders than in nonresponders (P = 0.0005). Pretreatment 2',5'-oligoadenylate synthetase levels did not predict response. CONCLUSIONS: Interferon alfa, 10 MU/m2 three times weekly for 12 weeks, is effective in eradicating HBV replication in a predominantly homosexual male population not coinfected with HIV.

2',5'-Oligoadenylate Synthetase↗

Dialyser reuse: an automated system using peracetic acid.

For 3 years starting in April 1989, in a 17-station, in-centre haemodialysis unit at the Toronto Western Hospital, re-use of dialysers was performed using the Renatron-2 Dialyser Reprocessing System with peracetic acid as a sterilant. During this period 40,234 treatments were carried out and dialysers were used an average of 4.2 times. Net savings, after taking into account the total costs of re-use, averaged Can $309,000,000 per year. There were no deaths and no discernible morbidity attributable to the practice of re-use. We conclude that dialyzer re-use is an effective way to reduce the costs of haemodialysis and is entirely safe providing that it is carried out properly.

Canada↗

Peritoneal dialysis-related peritonitis treatment recommendations. 1993 update. The Ad Hoc Advisory Committee on Peritonitis Management. International Society for Peritoneal Dialysis.

In conclusion, the recommendations provided in this document represent a distillation of various experiences, as well as data obtained from published studies. It is hoped that this compilation will provide a basis upon which future developments and advances can be made in the therapeutic approach to infectious complications of peritoneal dialysis.

Anti-Bacterial Agents↗

Is intraperitoneal tobramycin ototoxic in CAPD patients?

In 40 CAPD patients treated for peritonitis, the authors did a prospective study of ototoxic effects of intraperitoneal tobramycin. They evaluated cochlear function in pure-tone threshold audiograms over a range of frequencies from 250-10,000 Hz, in the speech-reception threshold test and in the speech-discrimination test. These tests were performed within 48 hours of initiation of tobramycin treatment and within 2 or 3 weeks of the drug's discontinuation. With the aminoglycoside doses used in this study, no statistical difference between the mean baseline and mean follow-up hearing levels was seen in these 40 patients. However, according to the standard criteria of ototoxicity, the hearing in 10 of 40 patients (25%) deteriorated after tobramycin, while it improved in seven patients (17.5%). In the remaining 23 (57.5%), hearing remained stable. With respect to the risk factors for ototoxicity such as advanced age, increased duration of treatment, elevated plasma aminoglycoside levels, concomitant treatment with other ototoxic drugs, pre-existing hearing loss, renal dysfunction and hyperthermia, no statistically significant difference was demonstrated between the patients with deteriorated, stable or improved hearing. The results of this study do not confirm that tobramycin given intraperitoneally to CAPD patients produces auditory toxicity. The hearing deterioration observed in 10 patients may be due to synergistic factors. The improvement observed in 7 patients could not be explained.

Audiometry, Pure-Tone↗

Septicemia in long-term jugular hemodialysis catheters; eradicating infection by changing the catheter over a guidewire.

By convention, septicemia occurring from an infected vascular catheter is treated with antibiotics and removal of the catheter. This approach, used with surgically implanted long-term catheters would be expected to result in loss of the vascular access site. During a 57 month period, we treated 21 episodes of septicemia secondary to infection of long term indwelling double lumen jugular venous catheters in our hemodialysis unit. Seventeen of 21 episodes were managed successfully by changing the catheter over a guidewire, thus preserving the access site. No relapse was observed after the antibiotic therapy was stopped. Only four patients required complete removal of the catheter and subsequent use of another site.

Actuarial Analysis↗

Peritonitis-related deaths in continuous ambulatory peritoneal dialysis (CAPD) patients.

A total of 636 episodes of peritonitis occurred in 440 patients who entered our continuous ambulatory peritoneal dialysis (CAPD) program from September 1977 to February 1988. Sixteen patients (8 male and 8 female, aged 37-77 years) died during an episode of peritonitis (fatality rate 2.5%). They had been on CAPD for 3 to 105 (average 39) months. Six of them were diabetics. The peritonitis rate among these 16 patients were 1 episode per 12 patient months, while the corresponding figure for the whole (440) CAPD population was 14 patient months. Risk factors present in the 16 patients were: cardiovascular disease (12), cerebrovascular accident (2) peripheral artery disease (1) and pulmonary fibrosis (1). Fever and leukocytosis were present on admission in 11 patients, while total serum proteins and albumin were significantly lower (p less than 0.001) than the corresponding values before peritonitis (56 +/- 8 vs. 65 +/- 5). Staph. aureus was isolated in 8 patients (50%), multiple organisms in 6, Pseudomonas and Candida albicans in 1 each. An abdominal abscess was found in 4 (25%) patients. The peritoneal catheter was removed between the 5th and 10th day in 6 and after the 10th day in 7 patients. Peritonitis with sepsis was the cause of death in 13 patients. Contributing factors were cardiovascular accident in 9, uremic coma in 2, extensive GI bleeding in 2, GI perforation in 2, intestinal infarction in 1, and pneumonia in 2 patients. We conclude that the risk of peritonitis-related death in CAPD patients is increased with Staph. aureus or multibacterial peritonitis. Contributing factors are concomitant cardiovascular disease and delayed (greater than 5 days) catheter removal.

Cardiovascular Diseases↗

Foscarnet therapy of cytomegalovirus retinitis in AIDS.

Cytomegalovirus (CMV) retinitis is the most common cause of blindness in AIDS. Twenty patients were treated with a 21-day course of foscarnet therapy by continuous infusion. Response to therapy was good in eight (47%) of 17 evaluable patients; partial arrest of progression was observed in eight (47%); and no response was obtained in one (6%). Foscarnet therapy did not lead to suppression of urinary excretion of CMV in four of 12 patients who nonetheless had improvement in retinal lesions. Toxic effects, especially reversible renal failure, were common, with blood creatinine increase in 50% and dialysis in two patients. Renal toxicity occurred primarily during the third week of therapy. Anemia (hemoglobin less than 80 g/L) occurred in 10 patients after a mean of 14.5 +/- 5.1 days of therapy and required transfusion. Review of this study and of data from a previous case series, however, was inconclusive regarding the additional benefit of a third week of therapy. Maintenance therapy was given to seven patients. Four had recurrence of CMV retinitis at a mean interval of 62 +/- 52 days. Only one patient has maintained prolonged remission on maintenance (greater than 24 weeks). Toxicity on the maintenance protocol included anemia (two of seven patients) and increased creatinine blood levels (one of seven patients). Zidovudine therapy in six patients did not contribute to increased toxicity of induction or maintenance therapy. Drug levels during continuous infusion were stable for individual patients but showed wide inter-patient variability. Peak levels of post-maintenance infusion varied both within and between patients.

Acquired Immunodeficiency Syndrome↗