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We investigated the predictors of serum albumin and the relationship between serum albumin and urea kinetic indices in continuous peritoneal dialysis (CPD). In a training set (TS) of 143 urea kinetic studies performed in 92 CPD patients, stepwise logistic regression identified high/high-average peritoneal solute transport, diabetes, advanced age and high daily drain volume normalized by body water as predictors of low serum albumin (< 35 g/liter). This analysis was then substantiated in a validation set (VS) of 187 kinetic studies performed in another 102 CPD patients. The calculated area under the receiver operating characteristic (ROC) curve by this logistic regression model was 0.782 (95% CI, 0.745 to 0.819). Logistic regression was repeated in the TS using only the first kinetic study from each patient, and it identified high/high-average peritoneal solute transport, diabetes, and advanced age as predictors of low albumin. Using only the first kinetic study from each patient in the VS, the second logistic regression model calculated an area under the ROC curve equal to 0.850 (95% CI, 0.810 to 0.890). The relative risk (RR) of serum albumin < 35 g/liter was computed for all kinetic studies after combining the TS and the VS and using non-diabetic CPD subjects aged < or = 61 years with low/low average peritoneal solute transport as the reference group. The RR with only one risk factor present ranged from 1.076 (age > 61 years) to 6.792 (high/high-average transport). The RR with two risk factors present ranged from 5.200 to 9.729. The RR with all three risk factors present was 9.100 (95% CI, range 3.923 to 21.111). A subset of 37 CPD patients had a second urea kinetic study 8 +/- 5 months after an increase in the amount of dialysis due to low urea clearance and/or uremic symptoms. The weekly KT/V urea increased from 1.40 +/- 0.24 to 2.10 +/- 0.31 after the increase in the CPD dose. With the increase in dialysis, the protein catabolic rate increased substantially; however, the mean serum albumin remained stable (from 33.9 +/- 4.6 to 33.3 +/- 6.2 g/liter; decrease 18; increase 15; same 4). In comparison to the subjects who had a decrease in serum albumin after the increase in KT/V, those with the increase in serum albumin were younger (44.2 +/- 11.2 vs. 54.3 +/- 16.2 years, P = 0.044) and had a higher serum urea after the increase in the dose of CPD (22.4 +/- 7.8 vs. 17.0 +/- 6.0 mmol/liter, P = 0.037). We conclude that the major predictors of low serum albumin in CPD are advanced age, diabetes, and high/high-average peritoneal solute transport, but not urea kinetic studies. An increase in the dose of dialysis does not cause a consistent rise in serum albumin in underdialyzed CPD subjects. However, a subset of younger patients may be able to increase their serum albumin in response to the increase in KT/V.

Objectives: To identify the most advantageous formula for estimating creatinine clearance (CCr) and to establish a dose of dialysis that will ensure minimal acceptable levels of creatinine clearance in patients on continuous peritoneal dialysis (CPD)., Design: Analysis of all CCr studies performed in CPD patients over 40 months., Setting: All four dialysis units following CPD patients in one city. One dialysis unit is government-owned, one is university-affiliated, and two are community based., Participants: One hundred and ninety-four patients representing almost the entire CPD population in Albuquerque., Interventions: Creatinine and urea clearance studies were performed in 24-hour urine and drained dialysate samples. Creatinine clearance (peritoneal plus urinary) was normalized to either 1.73 m2 body surface area (CCr) or body water estimated by the Watson formulas (KT/VCr). CCr and KT/VCr were either corrected by averaging urinary creatinine and urea clearances or were not corrected. Two dialysis units were designated as the training set (92 patients, 143 clearance studies) and the other two units as the validation set (102 patients, 181 clearance studies)., Main Outcome Measures: Minimal acceptable creatinine clearance levels were determined in the training set by computing the creatinine clearance value corresponding to 1.70 weekly KT/V urea by linear regression. Logistic regression models predicting low creatinine clearance were developed in the training set and were tested in the validation set., Results: The following weekly creatinine clearance values corresponded to 1.70 KT/V urea: corrected CCr 52.0 L/1.73 m2, uncorrected CCr 54.4 L/1.73 m2, corrected KT/VCr 1.46, uncorrected KT/VCr 1.53. Logistic regression identified as predictors of low creatinine clearance low daily urine volume (UV) and low daily dialysate drain volume/body water (DV/V) for all four creatinine clearance formulas, plus low/low-average peritoneal solute transport (only for uncorrected CCr) and serum creatinine (for both KT/VCr formulas). In the validation set, the predictive models produced an area under the receiver operating characteristic (ROC) curve between 0.835 and 0.919 indicating very good predictive accuracy. For corrected CCr and anuria, the regression model produced a minimal normalized drain volume (DV/V) value consistent with minimal acceptable CCr equal to 0.305 L/L per 24 hours. This DV/V cutoff detected low corrected CCR in validation set anuric subjects (n = 55) with a sensitivity of 85% and a specificity of 71%. For uncorrected CCR and anuria, DV/V cutoffs were 0.273 L/L per 24 hours (high/high-average peritoneal solute transport) and 0.420 L/L per 24 hours (low/low-average transport). Sensitivity and specificity of these cutoffs in validation set anuric subjects were 87% and 85%, plus 86% and 33%, respectively., Conclusions: The uncorrected CCr appears to be the most advantageous creatinine clearance formula in CPD, because it allows the use of peritoneal solute transport type in the calculation of the minimal required normalized drain volume. The minimal acceptable uncorrected CCr is 54.4 L/1.73 m2 weekly. To achieve this uncorrected CCr in anuria, the required minimal normalized drain volume is 0.273 L per liter of body water daily if peritoneal solute transport is high or high-average and around 0.420 L per liter of body water daily if peritoneal solute transport is low or low-average. The required total daily drain volume is computed by multiplying the required normalized drain volume by body water.

This study attempted to define the minimal dose of dialysis needed to produce a target KT/V in continuous peritoneal dialysis (CPD). In a training set of 143 clearance studies performed in 92 CPD patients, logistic regression identified low urine volume (UV) and low dialysate drain volume normalized by body water (DV/V) as predictors of weekly KT/V urea < or = 1.70. Solution of the regression equation with UV fixed at 0.00 1/24 h and at different probabilities of low KT/V provided a series of minimal DV/V values consistent with weekly KT/V > or = 1.70 in anuria. The accuracy of the logistic regression model and of the DV/V cut-offs was tested in a validation set (VS) of 189 urea kinetic studies performed in another 102 CPD patients. In the VS, the area under the Receiver Operating Characteristic curve generated by the regression model was 0.832 (95% Confidence Interval: 0.798-0.866). The DV/V cut-off value of 0.301 per 24 h, calculated by solving the regression model at p = 0.442 and with UV = 0, identified studies with weekly KT/V < 1.70 with a sensitivity of 89.3% and a specificity of 78.1% in anuric VS subjects (n = 60). Use of only the first urea kinetic study from each patient did not modify the predictors of KT/V or the cut-off values derived from solution of the regression model. The DV/V cut-off of 0.324 per 24 h, derived from the logistic regression model predicting KT/V < or = 1.90, identified KT/V < 1.90 in VS anuric subjects with a sensitivity of 94.3% and a specificity of 81.0%. Low UV and DV/V predict low KT/V urea in CPD. Prescribed 24 h exchange volume in anuric CPD subjects should be calculated to produce DV/V values exceeding 0.301 1/24 h per 1 body water for a KT/V of 1.70 and 0.324 1/24 h per 1 body water for a target weekly KT/V of 1.90.

Diabetic control in 110 diabetics (39 type I and 71 type II), who had been on continuous ambulatory peritoneal dialysis (CAPD) for at least 3 months, was considered good (group G, n = 63) or poor (group P, n = 47) if > 50% or < or = 50% of glucose measurements, respectively, were within 3.3-11.1 mmol/L. Compared to group P, group G had more type I diabetics and fewer type II diabetics; higher serum cholesterol and lower serum creatinine; higher rates of blindness, autonomic neuropathy, congestive heart failure, myocardial infarction, cerebrovascular accidents and extremity gangrene; higher annual rates of peritonitis (1.47 +/- 1.31 vs 0.98 +/- 1.19 episodes/patient-year), exit-site/tunnel infection (0.83 +/- 1.14 vs 0.39 +/- 0.68 episodes/patient-year), and catheter loss (0.81 +/- 0.59 vs 0.39 +/- 0.52 episodes/patient-year); and longer hospitalization (38 +/- 31 vs 14 +/- 15 days yearly). All differences were significant at p = 0.05 or lower. According to life-table analysis, median patient survival was 25 +/- 3 months in group P and 85 +/- 17 months in group G (p < 0.0001). Technique survival was 14 +/- 2 months for group P and 28 +/- 4 months for group G (p < 0.0001). Good diabetic control in diabetics on CAPD is associated with better outcome and constitutes, therefore, a desirable therapeutic goal.

Eight diabetic men with poor glycemic control, probably worsened by severe congestive heart failure and gastroparesis, were sequentially dialyzed by CAPD and hemodialysis. Mean blood glucose concentration, blood glycosylated hemoglobin, and insulin dose were higher during CAPD than during hemodialysis. Among blood glucose determinations, however, the frequency of hypoglycemia (glucose less than 3.3 mmol/L) was higher during hemodialysis (13.2 +/- 8.9%) than during CAPD (2.8 +/- 2.1% p = 0.012), whereas the frequencies of hyperglycemia (glucose greater than 11.1 mmol/L) and euglycemia (glucose between 3.5 and 11.1 mmol/l) did not differ between the two dialysis modalities. Furthermore, hypoglycemia was severe during hemodialysis and was associated with two deaths. There were no deaths linked to abnormalities in blood glucose concentration during CAPD. When hypoglycemia is frequent in diabetics with poor glycemic control, CAPD is preferable to hemodialysis.

The authors analyzed the outcome of 56 episodes of cardiopulmonary resuscitation (CPR) in dialysis patients. Eleven patients (20%) left the hospital alive. Univariate analysis showed that a functional cause of cardiac arrest, absence of rib fractures, and the occurrence of cardiac arrest in the dialysis or intensive care units were associated with a favorable outcome. Logistic regression showed that the outcome of CPR was related to the presence of rib fractures, cause of arrest, degree of preexisting heart disease, and patient age. Despite the high incidence of rib fractures (77%), the outcome of CPR in dialysis patients is similar to its outcome in the general population.

Urokinase or streptokinase was instilled intraperitoneally as an adjunct to the antibiotic therapy in 16 episodes of relapsing or persistent peritonitis in CAPD patients. In eight patients the combination of antibiotics and intraperitoneal thrombolytic agents resulted in clearing of the infection with no recurrences. The treatment failed in eight other patients, who had their peritoneal catheters removed. Six of the last eight patients had either abdominal wall abscesses or persistence of the bacteria on the wall of the peritoneal catheter. Elevated post-intraperitoneal instillation peritoneal fluid neutrophil counts and positive post-instillation peritoneal fluid cultures predicted failure of the intraperitoneal instillation of thrombolytic agents in most instances. Intraperitoneal instillation of urokinase or streptokinase may help cure approximately 50% of the episodes of relapsing for persistent peritonitis. Post-instillation peritoneal fluid cell counts and cultures should be monitored. Radiologic investigation for abdominal wall or intraabdominal abscesses is indicated if intraperitoneal instillation of urokinase or streptokinase fails to eradicate peritonitis.

Clinical course, complications and outcome were analyzed in 75 patients (14 women, 61 men) who started CAPD at age 55 years or older (55-81). These patients were separated in three groups. Group A patients had high risk for vascular disease (diabetes, hypertension, N = 45), group B patients had a presumed lower risk for vascular disease (primary renal disease, N = 22), and group C patients had miscellaneous conditions (N = 8). Group A was compared to group B. Patient and technique survival was statistically higher for group B than for group A. The rates of peritoneal dialysis related complications (peritonitis, tissue infections, catheter loss, hernias) were comparable between groups A and B. Hernias were seen frequently in all groups and had severe sequellae, including discontinuation of CAPD. Catastrophic vascular events were also seen in all groups, but the frequency of such events, particularly of catastrophic vascular events of the limbs, was statistically higher in group A than in group B. Vascular disease accounted for the majority of deaths in all groups. Four patients died from cardiovascular instability soon after changing from CAPD to hemodialysis. In conclusion, vascular disease is the major factor limiting survival in older CAPD patients. CAPD is superior to hemodialysis for a relatively small fraction of older patients with severe cardiovascular instability.

We analyzed routine serum potassium concentration measurements and conditions temporally associated with abnormalities in potassium concentration in outpatients on chronic hemodialysis (136 nondiabetics, 36 diabetics) and continuous ambulatory peritoneal dialysis (16 nondiabetics, 10 diabetics). The following potassium concentration frequencies were found: prehemodialysis, nondiabetics: normal 51.3%, severe hyperkalemia (greater than 6.0 mmol/l) 10%, severe hypokalemia (less than 3.0 mmol/l) 0.3%; diabetics: normal 57.8%, severe hyperkalemia 8.7%, severe hypokalemia 0.5%. Peritoneal dialysis, nondiabetics: normal 73.7%, severe hyperkalemia 0.6%, severe hypokalemia 4.9%; diabetics: normal 72.5%, severe hyperkalemia 0.9%, severe hypokalemia 2.9%. Normokalemia and severe hypokalemia were significantly (chi 2 test) more frequent in peritoneal dialysis than in prehemodialysis, whereas severe hyperkalemia was more frequent in prehemodialysis serum samples. No difference was found between nondiabetics and diabetics for either form of dialysis. 50% of prehemodialysis episodes of hyperkalemia were diet-induced. Hyperkalemic drugs and anuria were not associated with a higher risk of prehemodialysis hyperkalemia, but each one of 3 abnormalities, very high BUN (greater than 40 mmol/l), metabolic acidosis (TCO2 less than 15 mmol/l) and, in diabetics, severe hyperglycemia (serum glucose greater than 30 mmol/l), was associated with a statistically higher risk of hyperkalemia.

We analyzed causes and clinical associations of hemodialysis performed during the course of CAPD in 71 patients (34 diabetic) on CAPD between 1978 and 1988. Thirty seven patients had at least one hemodialysis during CAPD. Causes (multiple for some patients) included poor compliance with CAPD (20 patients), peritoneal catheter loss from infection (16 patients), and miscellaneous other conditions (18 patients). Hemodialysis rates were similar between diabetic and non-diabetic CAPD patients. Compared to non-hemodialyzed patients, CAPD patients hemodialyzed for poor compliance had higher rates of peritonitis (one episode per 8.3 patient months vs one episode per 23.4 patient months, p less than 0.001) and catheter loss (one loss per 27.7 patient months vs one loss per 112.0 patient months, p less than 0.001), and exhibited a trend towards more deaths (annual mortality 30.9% vs 14.3%, p = 0.067). Hemodialysis performed in CAPD patients because of poor compliance is associated with higher rates of peritonitis and catheter loss, and, probably, with increased mortality.

We measured by affinity chromatography glycosylated hemoglobin levels in the blood of 43 diabetic and nondiabetic patients (139 measurements) on long-term dialysis therapy (continuous ambulatory peritoneal dialysis and hemodialysis) to determine the usefulness of this method of estimating glycemic control in diabetic persons on dialysis therapy. In nondiabetic patients, glycosylated hemoglobin levels were within the normal range (4.0% to 6.8% of total blood hemoglobin levels) for both continuous ambulatory peritoneal dialysis and hemodialysis. Glycosylated hemoglobin values correlated significantly with fasting blood glucose levels, serum urea levels, and serum total carbon dioxide content. By stepwise regression, fasting blood glucose values accounted statistically for .54 of the variability (R2) in glycosylated hemoglobin. The contribution of the other variables to this variability was minimal. In 9 diabetic patients (3 on hemodialysis), glycosylated hemoglobin levels correlated significantly with average daily blood glucose levels. Regression of the fasting blood glucose value on glycosylated hemoglobin was similar between continuous ambulatory peritoneal dialysis and hemodialysis. Measuring glycosylated hemoglobin levels by affinity chromatography is a suitable method for assessing glycemia in dialysis patients.