Hariprasad S. Trivedi

Predictors of Death in Patients on Peritoneal Dialysis: The Missouri Peritoneal Dialysis Study

Background: The study was designed to identify predictors of death in subjects on peritoneal dialysis (PD). Methods: The population consisted of patients initiated on PD at the University of Missouri-Columbia and Dialysis Clinic Incorporated from January 1, 1990, through December 31, 1999. Baseline variables included demographics, clinical data, initial measures of nutritional status, adequacy, and transport characteristics. Co-morbidities were scored using a modified version of the Index of Coexistent Disease. Ongoing (during the course of PD) variables consisted of clinical characteristics and weighted time average of a number of laboratory, adequacy, and nutritional variables. The variables were screened using a univariate procedure, and then analyzed using stepwise logistic regression to evaluate their independent relation to death. Results: There were 105 men and 86 women – 180 Caucasians, 10 African-American, 1 Asian, mean age 61 ± 13 (SD) years, and mean duration of follow-up 21 ± 18 months. Eighty-two patients suffered the outcome of death. Lean body mass (LBM) at the initiation of PD was negatively associated with the risk of death (p < 0.01). In addition, the need for a partner to perform PD, total morbidity count, and the summated severity score of all co-morbidities were associated with an increased risk of death. The analysis of ongoing variables revealed that serum phosphate (negative association, p = 0.02) and number of hospitalization days per month on PD (p = 0.0006) were associated with an increased risk of death. Conclusion: Phosphate levels and LBM are strong negative predictors of death in PD subjects. Further, patients who need the assistance of a partner to perform PD have decreased survival.

Use of double-lumen dialysis catheters : Loading with locked heparin

Improvement in double-lumen catheter usage could provide lasting, user friendly angioaccess for patients on hemodialysis (HD), especially those on home HD. These catheters are routinely locked with concentrated heparin at the end of an HD session, in a volume corresponding to the lumen capacity. At the start of the next HD session, this heparin is aspirated with a small amount of blood and discarded. The cumulative blood loss over a long period becomes significant. The authors aimed to study whether a predetermined loading dose of heparin could be used to lock the catheter, and be administered as such during the next HD session. Thirteen patients were evaluated during four HD sessions (Rx 1 through 4; Rx 4 followed a weekend). Prior to the first study HD (Rx 1), the catheter was locked with 10,000 units heparin per lumen, as per our standard practice. Therefore, Rx 1 was considered the standard for the purpose of the study. On study HD (Rx 1 through 4), the catheter was locked with the patients loading dose (half per lumen). The heparin loading dose was given as follows: Rx 1 and 2 = fresh heparin; Rx 3 and 4 = locked heparin. Again, activated clotting time (ACT) was measured periodically and heparin was given according to an ACT-based sliding scale. The first ACT and heparin level (drawn after the loading dose) were compared for Rx 1 vs Rx 2, 3, and 4. The mean (±SEM) values were as follows: Rx 1 —first ACT = 299.2 ± 16.5 sec, heparin level = 1.25 ± 0.15 IU/ml; Rx 2—first ACT = 305 ± 20 sec, heparin level = 1.1 ± 0.09 lU/ml; Rx 3—first ACT = 293 ± 18.5 sec, heparin level = 1.1 ± 0.19 lU/ml; and Rx 4—first ACT = 288 ± 24.1 sec, heparin level = 1.07 ± 0.16 IU/ ml. The mean of the differences between Rx 1 and Rx 2, 3, and 4, were not significantly different for all of the analyzed parameters. No catheter was lost during the study period. The results suggest that locked heparin can be effectively used as the loading dose. Advantages of this method include decreased blood wastage, heparin cost savings corresponding to the cost of concentrated heparin (approximately

Discrepancy in the Epidemiology of Nondiabetic Chronic Renal Insufficiency and End-Stage Renal Disease in Black and White Americans: The Third National Health and Nutrition Examination Survey and United States Renal Data System

156.00 per patient year for HD three time weekly), and at least one less connection per catheter lumen. The latter would possibly reduce the risk of transluminal catheter related infections.

A prospective, randomized, open labeled crossover trial of fosinopril and theophylline in post renal transplant erythrocytosis.

Background: Epidemiologic data regarding the prevalence of chronic renal insufficiency (CRI) [from the third National Health and Nutrition Examination Survey (NHANES III)] and the incidence of end-stage renal disease (ESRD) [from the United States Renal Data System (USRDS)] are available. However, reconciliation of these separate particulars has not been performed objectively. The present work examines the epidemiology of CRI of nondiabetic etiology and ESRD in black and white Americans aged 20 years or greater. Methods: Based on the incidence of ESRD in the study population (USRDS), the numbers of subjects with decreased Modification of Diet in Renal Disease (MDRD) glomerular filtration rate (GFR) <80 ml/min/1.73 m2, <60 ml/min/1.73 m2 and <30 ml/ min/1.73 m2 in 1991 (on December 31 1991) were mathematically obtained based on a linear model of GFR decline. Similarly, the corresponding estimated prevalence figures of CRI were derived based on analyses of NHANES III data and the 1991 census counts of black and white Americans (aged 20 years or more). Unadjusted and adjusted (correcting for calibration differences between the NHANES III and MDRD laboratory) prevalences were calculated. Subsequently, the prevalence of different degrees of CRI based on the incidence of ESRD (USRDS) was compared to the corresponding figures of the estimated prevalence of CRI (NHANES III). Results: By analyses of USRDS data, on December 31 1991, the prevalence of different degrees of reduced GFR in the study population was estimated to be as follows: 396,863 subjects with GFR <80 ml/min/1.73 m2; 272,932 subjects with GFR <60 ml/min/1.73 m2, and 115,065 subjects with GFR <30 ml/min/1.73 m2. Using actual NHANES III creatinine values, the prevalence of different degrees of CRI in the study population was estimated as follows: 92,595,211 people with GFR <80 ml/min/1.73 m2; 20,754,099 people with GFR <60 ml/min/1.73 m2, and 415,082 people with GFR <30 ml/min/1.73 m2. The data suggest that approximately 0.43% of subjects with GFR <80 ml/min/1.73 m2, 1.32% of subjects with GFR <60 ml/min/1.73 m2 and 27.72% of subjects with GFR <30 ml/ min/1.73 m2 reached ESRD (USRDS). Using adjusted NHANES III creatinine values (downwardly correcting the NHANES III creatinine values to account for calibration differences with the MDRD measurements), the prevalence of different degrees of CRI in the study population was estimated as follows: 28,512,939 people with MDRD GFR <80 ml/min/1.73 m2 (17.86%); 5,364,136 people with MDRD GFR <60 ml/min/1.73 m2 (3.36%), and 255,435 people with MDRD GFR <30 ml/min/1.73 m2 (0.16%). Of these, about 1.39% of the people with MDRD GFR <80 ml/min/1.73 m2, 5.09% of the people with MDRD GFR <60 ml/min/1.73 m2 and 45.07% of the people with MDRD GFR <30 ml/min/1.73 m2 in 1991 reached ESRD. Conclusion: There is a major discrepancy in the epidemiology of nondiabetic CRI and ESRD amongst black and white Americans. The reasons for this need further study.

Reproducibility of the peritoneal equilibration test in CAPD patients

Angiotensin converting enzyme inhibitors (ACEI) and theophylline have been reported to decrease the elevated hemoglobin (Hgb) and hematocrit (Hct) levels in the renal transplant recipients with erythrocytosis. We conducted a prospective randomized, open labeled, crossover trial with theophylline, and an ACEI, fosinopril in nine stable renal transplant recipients with erythrocytosis. Aim of the study was to determine and compare the efficacy of these medications in stable renal transplant patients. At three months, compared to baseline, fosinopril significantly reduced the elevated hemoglobin (Hgb 17.2 ± 0.6 vs. 14.9 ± 1.4 gm/dL, p = 0.0023), and hematocrit levels (Hct 51.3 ± 2.4 vs. 43.7 ± 4.6%, p = 0.003). In contrast theophylline therapy was associated with a non-significant rise in hemoglobin (17.4 ± 0.7 vs. 18.1 ± 0.9 gm/dL, p>0.05) and hematocrit (52.4 ± 2.7 vs. 54.7 ± 3.9%, p>0.05). With fosinopril compared to theophylline, there was a significant difference in the change in hemoglobin (baseline to three months 2.8 ± 1.7 vs. −0.7 ± 0.69 gm/dL respectively, p = 0.017), and the change in hematocrit (baseline to three months 9 ± 6 vs. −2.3 ± 2.7% respectively, p = 0.027). Four patients (44.4%) did not tolerate theophylline and did not complete the theophylline arm. To conclude, in our study, fosinopril effectively decreased the elevated hemoglobin and hematocrit in patients with post transplant erythrocytosis, and was superior to theophylline, while theophylline was ineffective and poorly tolerated in this condition.

Predictors of Hospitalization in Patients on Peritoneal Dialysis: The Missouri Experience

A study was undertaken to evaluate the short-term reproducibility of peritoneal equilibration test (PET) results. Nine patients with end-stage renal disease undergoing continuous ambulatory peritoneal dialysis underwent PETs under similar conditions on 2 consecutive days. Dialysate samples were obtained at 0 hours, midcycle, and at the end of exchange. There were no significant differences between the mean ratios at 4 hours for creatine, urea nitrogen, potassium and protein, and glucose between PET 1 and PET 2. A standard PET is highly reproducible when repeated under similar conditions. Reproducibility is better for ratios of creatinine, glucose, urea nitrogen, and potassium than for protein.

Erythropoietin Therapy in Pre-Dialysis Patients with Chronic Renal Failure: Lack of Need for Parenteral Iron

Background: We analyzed a large number of demographic and biochemical variables to identify predictors of hospitalization in subjects on peritoneal dialysis (PD). Methods: All patients initiated on PD at our center from January 1990 through December 1999 were included. The following variables at the initiation of PD were included: demographics, clinical data, nutritional and adequacy parameters, transport characteristics, and various co-morbidities. Co-morbidities were graded for severity using a modified version of the Index of Coexistent Disease. Variables included during the course of PD consisted of weighted time average of a number of laboratory, adequacy, and nutritional parameters along with the number of peritonitis episodes per year. Stepwise linear regression was used following a univariate screening procedure to identify independent predictors of the outcome of hospitalization days per month on PD. Results: The subject population consisted of 191 subjects (105 men, 86 women; 180 Caucasians, 10 African-American, 1 Asian). The mean age was 61 ± 13 (SD) years and mean duration of follow-up was 21 ± 18 months. The baseline variable analysis revealed that the presence of partner to perform PD predicted increased hospitalization (p < 0.0001). Additionally, the presence and severity of peripheral vascular disease and residual renal Kt/V at baseline (negative association) predicted increased hospitalization. In the analyses of ongoing variables, stepwise linear regression solely identified weighted time average albumin as a strong negative predictor of hospitalization (p < 0.0001). Conclusion: A comprehensive analysis of a large number of variables revealed that serum albumin during the course of PD (negative association) and the need for partner to perform PD strongly predicted increased hospitalization in PD subjects.

A study of the extracorporeal rate of blood flow and blood pressure during hemodialysis

Background: During erythropoietin therapy, scant information exists regarding the optimal target percent saturation of transferrin (TSAT), ferritin and the mode and amount of iron supplementation in pre-dialysis patients with anemia due to chronic kidney disease (CKD). Hypothesis: Pre-dialysis CKD patients may have different needs for iron supplementation than end-stage renal disease subjects during erythropoietin therapy. Methods: Retrospective analysis of pre-dialysis CKD subjects (n = 31) treated with erythropoietin at our institution. Results: In this population our results showed that target hematocrit (33–36%) was achievable with erythropoietin (mean subcutaneous dose 86 ± 17 [SD] units/kg/week) without parenteral iron therapy. The hematocrit increased from a mean baseline value of 28.4 ± 2.7 to 33.6 ± 3.4% at time 1 (4–9 weeks, p < 0.0001), and to 37.7 ± 4.5% at time 2 (10–20 weeks, p < 0.0001). The hemoglobin concentration increased from 9 ± 0.9 g/dl at baseline to 10.7 ± 1.1 g/dl at time 1 (p < 0.0001) and to 12 ± 1.5 g/dl at time 2 (p < 0.0001). Subgroup analyses of patients prescribed <200 mg oral elemental iron per day (n = 10), those with TSAT <20% and/or ferritin <100 ng/ml (n = 19), and those prescribed erythropoietin <80 units/kg/week (n = 12), all showed a significant increase in hematocrit and hemoglobin. Conclusions: Our data show that pre-dialysis CKD subjects respond adequately to erythropoietin at or lower than recommended erythropoietin doses without parenteral iron. This response extends even to subgroups with TSAT and/or ferritin levels deemed to indicate iron deficiency in CKD subjects, and may be due to lack of existence of functional iron deficiency in this group of patients.

Nephrogenic Diabetes insipidus Presenting after Head Trauma

Hemodynamic instability is a common problem during hemodialysis (HD). The effect of blood flow rate (BFR) on blood pressure (BP) during HD has not been previously evaluated. Subjects receiving HD for the treatment of renal failure were enrolled (n=34). For each patient, during the last hour of 2 consecutive HD sessions the BFR was set at 200 mL/min for 30 min and at 400 mL/min for 30 min, during which period the fluid removal rate was kept constant. The order of the BFR alterations was randomized. The study procedure was repeated during the next HD session but with reversal of the order of the altered BFR. During each 30‐min period, BP was recorded at baseline and subsequently every 10 min. During the BFR of 400 mL/min, subjects had a higher systolic BP by an average of 4.1 mmHg compared with the BFR of 200 mL/min (95% confidence interval [CI] 0.22–7.98; p=0.038). Similarly, during the BFR of 400 mL/min, subjects had a higher diastolic BP by an average of 3.04 mmHg compared with the BFR of 200 mL/min (95% CI 0.55–5.53; p=0.017). Likewise, during the BFR of 400 mL/min, subjects had a higher mean arterial pressure by an average of 3.44 mmHg (95% CI 0.77–6.11; p=0.012). The findings suggest that during HD, BPs are maintained higher at higher BFRs as compared with lower BFRs.

Consultants for the American Journal of Nephrology 2003

Water diuresis after head trauma is most often due to central diabetes insipidus (DI). We report a patient with a history of a bipolar disorder and past lithium use who was noted to have polyuria and hypernatremia after head trauma. Inappropriate high sodium and volume replacement resulted in an increase in the polyuria. A lack of response to antidiuretic hormone/antidiuretic-hormone-like preparations led to the diagnosis of nephrogenic DI. The case illustrates the importance of calculating electrolyte-free osmolar clearance in the correction of hypernatremia. Persistence of the DI and mild renal impairment probably due to past lithium use are discussed.