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Lean body mass computed from creatinine kinetics (LBM) is an index of somatic nutrition and correlates with other nutrition indices in CAPD. However, LBM exceeding 90% of body weight (LBM/Wor = 0.9) may be an index of non-compliance, rather than nutrition. To test this hypothesis, we analyzed fluid and solute excretion in 40 CAPD patients with LBM/Wor = 0.9 (group A). The comparison group (group B) consisted of 885 CAPD patients with LBM/W0.9. Group A was younger (38.3+/-14.8 vs 54.7+/-14.7 yr) and had a lower percent of women (23.5% vs 41.1%) and diabetic subjects (17.5% vs 42.6%) than group B (at Por = 0.019). Group A also had lower body mass index (22.7+/-2.7 vs 25.8+/-5.1 kg/m2, P0.001) and serum albumin (33.0+/-6.7 vs 35.2+/-5.5 g/L, P = 0.014). Despite similar prescribed daily fill volumes (group A 8.3+/-2.4, group B 8.5+/-2.2 L/24 h) and similar D/P urea and creatinine values, group A had higher daily drain volume (11.0+/-3.6 vs 9.6+/-2.1 L/24 h, P0.001). Renal clearances were similar, while peritoneal and total clearances were apparently higher in group A. Creatinine excretion was higher in group A (27.4+/-5.1 vs 13.6+/-4.1 mg/kg x 24 h, P0.001), with a large part of the excess creatinine excretion in group A being accounted for by peritoneal excretion. The combination of an apparently high daily ultrafiltration volume (2.7 L/24 h on the average), unrealistically high creatinine excretion rate, and relatively poor nutrition (low body mass index and serum albumin) in group A is consistent with non-compliance. We suggest that the finding of LBM/Wor = 0.9 during a clearance study in CAPD should trigger an investigation for non-compliance.

Peritoneal dialysis (PD) patients are classified as underweight, normal weight, or obese by height/weight indices including body mass index (BMI) and the body weight/desired weight (W/DW) ratio. We compared these classifications of degree of obesity in 378 women and 555 men on PD. We used these cut-off values: for underweight, BMIor = 18.5 and W/DWor = 0.9; for obesity, BMIor = 30.0 and W/DWor = 1.2. The W/DW values were calculated assuming first a small frame, then a medium frame, and finally a large frame for all subjects. Regardless of sex or skeletal frame, BMI correlated highly with W/DW (r value between 0.98 and 0.99); however, the range of BMI values corresponding by linear regression to the normal range of W/DW (0.9-1.2) was narrower than the range of "normal" BMI (18.5-30.0). Consequently, regardless of sex or skeletal frame, smaller fractions of the patient population were classified as underweight or obese by BMI standards than by W/DW standards. The degree of agreement of the classifications of subjects as underweight, normal weight, or obese by BMI and W/DW was evaluated by Cohen's kappa ratio. The kappa ratio varied between 0.47 and 0.58, indicating a reasonable--but not high--degree of agreement beyond chance. The highest kappa ratios were obtained assuming a medium skeletal frame for both women and men. Substantial discrepancies are observed in the classification of PD patients as underweight, normal weight, or obese by BMI and W/DW. Further research is needed to identify the height/weight index that has the strongest association both with clinical outcomes and with other, more precise measurements of body fat content.

We analyzed the effect of diabetes on the decline of residual renal function during the course of CAPD in a cross-sectional study including 105 diabetic subjects (41 women) who had 207 clearance studies and 125 non-diabetic subjects (50 women, 265 clearance studies). CAPD duration was 11.5+/-10.5 months in the diabetic group (DG) and 16.8+/-18.6 months in the non-diabetic group (NDG, P0.001). The DG had lower urine volume than the NDG (0.52+/-0.46 vs 0.61+/-0.50 L/24-h, P0.05), while urine-to-plasma concentration ratio was higher in the DG for creatinine (13.5+/-9.4 vs 11.5+/-11.0, P0.05) and did not differ for urea. Weekly renal Kt/V urea (DG 0.51+/-0.57, NDG 0.53+/-0.49) and Ccr (DG 31.0+/-28.7 NDG 29.3+/-26.5 L/1.73 m2) did not differ. The slopes of the regressions of CAPD duration on renal clearances did not differ. These regressions allowed estimates of the time, from the onset of CAPD, at which renal clearances become negligible. These estimates differed for both urea clearance (DG 35.3, NDG 50.5 months) and creatinine clearance (DG 43.2, NDG 57.6 months). The slope of the regression of renal urea clearance on renal creatinine clearance was steeper in the DG, suggesting a higher renal creatinine clearance in the DG than in the NDG when renal urea clearance is the same in the two groups. Subtle differences in the rate of decline of renal function can be detected between diabetic and non-diabetic subjects on CAPD by detailed statistical analysis. These findings are supportive of the studies which have identified diabetes mellitus as a predictor of loss of residual renal function during the course of CAPD. In addition, the relationship between the renal urea and creatinine clearances differs between diabetic and nondiabetic subjects on CAPD. Therefore, the dose of CAPD required for adequate total clearances may differ between diabetic and non-diabetic subjects.

"Weight-height" indices including percent of ideal weight (%IW) and body mass index (BMI) are used to estimate degree of obesity in populations and are predictors of survival in dialysis patients. Amputation affects the relationship between weight and height independently of the degree of obesity. Corrections of both %IW and BMI for amputation have been published, but a National (U.S.) computer nutrition program used in the authors' institution uses only the correction for %IW. This study had two parts: (1) To test whether the weight-height cut-off values for weight deficit (%IW 90%, BMI 20 kg/m2) and obesity (%IW 120%, BMI 30 kg/m2) are compatible, we performed linear regression of BMI on %IW in peritoneal dialysis (PD) patients without amputations. In 349 men, BMI = 0.834 + 0.226 (%IW), r = 0.979. From this regression, the 95% confidence interval (CI) of BMI is 19.2-23.1 kg/m2 if %IW is 90%, and 26.1-29.9 kg/m2 if %IW is 120%. In 260 women, BMI = 2.194 + 0.184 (%IW), r = 0.974. From this regression, the 95% CI of BMI is 15.7-21.8 kg/m2 if %IW is 90%, and 21.3-27.3 kg/m2 if %IW is 120%. (2) To identify the direction and magnitude of the error of uncorrected BMI (BMIu) in dialysis patients with amputations, we analyzed weight-height indices in two groups of men by the computer nutrition program, which corrects %IW, but not BMI for amputation, and by the corrected BMI (BMIc) formula. In group A (amputation without height loss, n = 11), %IW = 110.2% +/- 16.9%, BMIu = 23.6 +/- 2.7 kg/m2, BMIc = 26.4 +/- 3.8 kg/m2 (p0.001, BMIc vs BMIu), and 5 of the 11 BMIu values fell below the 95% confidence band of the regression of BMI on %IW in patients without amputations. In group B (amputation with loss of height, n = 6), %IW = 92.7% +/- 19.9%, BMIu = 33.9 +/- 10.7 kg/m2, BMIc = 22.1 +/- 4.4 kg/m2 (p0.005, BMIc vs BMIu), and 5 of the 6 BMIu values fell above the 95% confidence band of the regression of BMI on %IW in patients without amputations.(1) The weight deficit cut-offs for %IW and BMI are compatible in non amputated men and women. (2) The obesity cut-offs for %IW and BMI are compatible in non amputated men, but not in non amputated women. (3) Amputation without height loss decreases BMIu, while amputation with height loss increases, in general, BMIu. (4) BMI should be corrected in PD patients with amputations.

To compare body water (V) estimates from the Chertow formula (Vc), which was derived in an end-stage renal disease population, to V estimates from the Watson formulas (Vw) in continuous ambulatory peritoneal dialysis (CAPD) patients. To identify CAPD patients in whom Vc is preferred to Vw for clearance studies.Retrospective analysis of clearance studies.Dialysis units of four academic medical centers.302 subjects on CAPD.613 clearance studies by standard methods.Comparisons between Vc and Vw, and between urea clearance normalized by Vc [(KtVc)ur] and Vw [(Kt/Vw)ur].Vc exceeded Vw by 3.5 +/- 1.6 L (p0.001), or 9.6% on average. This degree of overestimation of Vw is in the range of body water estimates found in CAPD subjects with severe volume overload (5% of body weight) in previous studies. Total (Kt/Nw)ur exceeded total (Kt/Vc)ur by 8.6%. By linear regression, Vc = -0.589 + (1.112 x Vw), r = 0.983. Vw exceeded Vc in only 12 studies. Young age, short height, low body weight, and low prevalence of diabetes characterized the studies with VwVc. Total (Kt/Vw)ur was adequate (or = 2.0 weekly) in 276 studies. Among these, 74 studies had inadequate total (Kt/Vc)ur (2.0 weekly). By logistic regression, the predictors of inadequate (Kt/Vc)ur, when (Kt/Vw)ur was adequate, included the presence of diabetes, great height, and long duration of CAPD.Vc provides estimates of body water exceeding those provided by Vw in a great majority of CAPD patients. Consequently, approximately 25% of the clearance studies that are adequate when Vw is used as the normalizing parameter may be inadequate when Vc is used. Vc may provide a more appropriate estimate of body water than Vw in CAPD patients with volume overload.

Normalized clearances for urea and creatinine were compared between 121 diabetic subjects (256 clearances) and 181 nondiabetic subjects (357 clearances) on continuous ambulatory peritoneal dialysis (CAPD) with four 2-L exchanges daily. Urea clearance was normalized by VWatson (Kt/Vur), while creatinine clearance was normalized by both VWatson (Kt/Vcr) and body surface area (Ccr). Height, weight, body water (V), and body surface area did not differ between the diabetic and the nondiabetic groups. Also, renal Kt/Vur, renal Kt/Vcr, renal Ccr, and peritoneal Kt/Vur did not differ between the groups. Weekly peritoneal Kt/Vcr (diabetic group 1.36 +/- 0.38, nondiabetic group 1.31 +/- 0.31, p = 0.048) and weekly peritoneal Ccr (diabetic group 47.6 +/- 11.0 L/1.73 m2, nondiabetic group 45.4 +/- 9.2 L/1.73 m2, p = 0.012) were both higher in diabetic subjects. The percentage of high/high-average transporters was higher in the diabetic group (64.9% vs 48.6% in nondiabetic group, p = 0.006). The following total (peritoneal + renal) weekly clearances were obtained: Kt/Vur, diabetic group 2.07 +/- 0.63, nondiabetic group 2.02 +/- 0.56, NS; Kt/Vcr, diabetic group 2.06 +/- 0.78, nondiabetic group 1.92 +/- 0.74, p = 0.026; Ccr, diabetic group 72.7 +/- 28.5 L/1.73 m2, nondiabetic group 67.2 +/- 26.4 L/1.73 m2, p = 0.013. Normalized total creatinine clearances are higher in diabetic subjects than nondiabetic subjects on the same CAPD schedule and with the same renal clearances of urea and creatinine and the same total Kt/Vur, because peritoneal creatinine clearances are higher in the diabetic subjects. This finding is caused by higher peritoneal transport in the diabetic subjects and is not an artifact caused by the normalization process.

To compare raw (not normalized) and normalized urea and creatinine clearances between women and men on continuous ambulatory peritoneal dialysis (CAPD). To study whether potential gender differences are due to the normalization process.Retrospective analysis of clearance studies.Dialysis units of four academic medical centers.The study included 302 subjects (135 women and 167 men) on CAPD with four daily exchanges and a 2-L exchange volume.Measurement of urea and creatinine clearances (261 in women, 352 in men) by standard methods. Body water (the volume of distribution, V, for both urea and creatinine) was estimated by the Watson anthropometric formulas.Comparison of raw and normalized clearances between women and men. Urea clearance was normalized by V (Kt/Vur), while creatinine clearances was normalized by both V (Kt/Vcr) and body surface area (BSA) (Ccr).Mean values of weekly total (peritoneal plus renal) raw clearances were higher in men (urea clearance: women 67.1 L, men 77.4 L; Ccr: women 61.7 L, men 78.3 L). Raw renal clearances were higher in men, while raw peritoneal clearances were comparable. Mean weekly total Kt/Vur was higher in women (2.19 vs 1.94 in men), mean weekly total Kt/Vcr did not differ between the genders (women 2.01, men 1.95), while mean weekly Ccr was higher in men (73.0 vs 64.7 L/1.73 m2 in women). When clearances differed, the differences were significant at p0.001. Men had greater height and weight, while women had greater body mass index. On the average, V in men exceeded V in women by 31%, while BSA in men exceeded BSA in women by only 12%.Normalization of clearances by V creates relatively higher clearance values in women, while normalization by BSA creates relatively higher clearance values in men. Thus the normalization process may create artificial differences in the normalized clearances between genders.

The authors developed formulae calculating the daily drain volume (DV) required for a target normalized peritoneal clearance of urea (Kt/V(ur)) or creatinine (Ccr, Kt/Vcr) in peritoneal dialysis (PD). DV depends on the target clearance, the peritoneal solute transport type, and the size of the person as expressed by body surface area (BSA) or body water (V). To illustrate the formulae, we constructed nomograms for the following weekly target clearances: Ccr = 60 L/1.73 m2, Kt/V(ur) = 2.0, Kt/Vcr = 1.8 (the value corresponding to a Ccr of 60 L/1.73 m2 in a linear regression of the two parameters in 476 clearance studies in continuous ambulatory PD [CAPD] patients). The PD schedules studied included CAPD, continuous cycling PD (CCPD) with one 2 L daytime dwell, and a combination of daytime CAPD and nighttime automated PD (APD) with 2 hr dwell times. Peritoneal transport was characterized as low, low-average, high-average, or high by the dialysate-to-plasma (D/P) creatinine concentration ratio in a peritoneal equilibration test (PET). The D/P value entered for each transport type was the appropriate 95% lower confidence limit of the mean D/P in actual studies (2 hr and 4 hr D/P from 102 PET studies and 5.5 hr D/P from 476 clearance studies in CAPD patients). For high transport, the required DV values were similar in all three PD schedules studied. For low transport, the required DV was much larger, comparatively, for CCPD and CAPD-APD than for CAPD. Furthermore, the DV values required for a weekly Kt/V(ur) of 2.0 were comparatively less than the DV values required for a weekly Kt/Vcr of 1.8 (Ccr of 60 L/1.73 M2). Calculation of the DV required for different PD schedules, a target peritoneal clearance, and the patients's size is feasible when the patient's peritoneal transport characteristics are known. This calculation also allows the selection of the least costly PD schedule. Current target values for urea and creatinine clearance are incompatible in anuric PD patients.

The purpose of this study was to determine if Kt/V urea in continuous ambulatory peritoneal dialysis (CAPD) could be estimated by a multivariate model based upon simple clinical observations. The study included 439 clearance studies in 301 CAPD patients followed in 8 dialysis centers. Weekly urea clearance, 24 h urine volume and 24 h drain volume were normalized to body water by the formulae of Watson (Kt/V, UV/V and DV/V respectively). Adequate dialysis was defined as Kt/Vor = 2.0 weekly. Subjects at 2 units were used to derive the models, while others were used for model validation. Stepwise multiple linear regression was performed on the derivation set (DS) to identify the clinical variables that correlated with Kt/V. The model was then used to estimate Kt/V for the validation set (VS). In the DS, 110 clearance studies were performed in subjects with residual renal function. Multiple linear regression showed that weekly Kt/V was defined by the expression: Kt/V=1.48 + 24.1 (UV/V) + 2.92(DV/V) - 0.049 (serum creatinine) (r=0.750, p0.001). In 204 VS studies, the correlation between estimated and measured Kt/V was 0.633. There were marked differences in the proportion of adequately dialyzed patients when Kt/V estimated from the formula shown was2.0, between 2.0 and 2.3, and2.3 weekly (7.9%, 54.7% and 79.7%, respectively; pO.001). In the 33 studies done in DS anuric patients, regression analysis showed the following: Kt/V=0.46 + 2.59 (DV/V) + O.009(age) (r=0.562; p=0.003). In 92 VS studies in anuric subjects, there was strong correlation between estimated and measured Kt/V (r=0.740). Again, there were marked differences in the frequency of adequate dialysis in anuric patients with estimated Kt/V2.0, between 2.0 and 2.3, and2.3 weekly (8.1%, 68.8%, and 100%, respectively; p0.001). The risk of low Kt/V can be estimated by multivariate linear models requiring only simple clinical measurements.

To characterize the factors affecting the decision to withdraw from dialysis, the authors compared patients withdrawing from dialysis (n=62) with patients dying from all other causes (n=242) over 21 years (1976-1996) in a single dialysis unit. Compared with those who died from other causes, patients who withdrew were older (67+/-11 vs 61+/-11 years); were more likely to have severe physical impairment (87% vs 62%) and severe restriction of activities of daily living (77% vs 46%); and had higher frequencies of congestive heart failure (81 % vs 62%), myocardial infarction (60% vs 42%), peripheral vascular disease (71 % vs 40%), and diabetes mellitus (66% vs 36%) (por = 0.014). Dialysis modality; duration of dialysis; the degree of family support; index of disease severity; the use of tobacco, alcohol, or illicit drugs; and the frequency of ischemic heart disease, dysrhythmia, pericarditis, cardiac arrest, cerebrovascular accident, hypertension, obstructive lung disease, cancer, and human immunodeficiency virus did not differ between the two groups. Stepwise logistic regression showed that dialysis during 1990-1996, severe limitation of activities of daily living, and diabetes mellitus were independent risk factors for withdrawal. During 1990-1996, 44% of the deaths were caused by withdrawal from treatment. In addition to other factors, dialysis in the 1990s is a strong predictor of withdrawal from dialysis. The reasons for the increased rate of withdrawal from dialysis in recent years, and the effect of this increased rate of withdrawal on mortality, need further evaluation.

Factors shown to affect serum albumin concentration in continuous peritoneal dialysis (CPD) were compared between two CPD populations residing in Greece (patient n = 108) and the United States (patient n = 194). Compared to the U.S. group, the Greek CPD population had higher serum albumin levels (35.1 +/- 4.6 vs 33.9 +/- 5.0 g/L, p = 0.031), was older (61.2 +/- 12.0 vs 52.7 +/- 16.5 years, p0.001), and had a greater number of high or high-average peritoneal solute transport types (69.4% vs 52.1%, p = 0.003). The American CPD population had a higher number of diabetics (53.1% vs 27.8%, p0.001), higher total Kt/Vurea (2.06 +/- 0.57 vs 1.93 +/- 0.46 weekly, p = 0.046), and higher total creatinine clearance (76.3 +/- 38.7 vs 63.4 +/- 23.5 L/1.73 m2 weekly, p0.001), while normalized protein nitrogen appearance values were comparable (0.95 +/- 0.21 in the Greeks vs 0.94 +/- 0.22 g/(kg x 24 hr) in the Americans, NS). A logistic regression model developed in the United States identified advanced age, diabetes, and high/high-average peritoneal solute transport as the predictors of hypoalbuminemia (serum albumin35 g/L). This model generated the following areas with 95% confidence intervals (CI) under the receiver operating characteristic (ROC) curve: in the Greek CPD population, ROC area 0.594 (95% CI 0.486-0.702); in the American CPD population, ROC area 0.850 (95% CI 0.810-0.890). In Greek CPD patients serum albumin appears to be affected by factors other than those identified in North America. This complicates comparisons of serum albumin, and probably morbidity and mortality, between CPD populations residing in different parts of the world.

The relative contribution of urinary volume (UV) and urine-to-plasma concentration ratios for urea (U/PUr) and creatinine (U/PCr) to urinary Kt/V urea (Kt/VU) and urinary uncorrected creatinine clearance (CCrU), respectively, was studied by simple and multiple linear regression analysis in 236 urea kinetic studies and 233 creatinine kinetic studies performed in 135 patients on continuous peritoneal dialysis (CPD). The following simple regressions were obtained: Kt/VU = 0.09 + 0.72 (UV), r = 0.75; Kt/VU = -0.01 + 0.11 (U/PUr), r = 0.55; CCrU = 12.06 + 56.46 + 46.46 (UV), r = 0.62; CCrU = 3.51 + 3.40 (U/PCr), r = 0.58. All r values were significant (p0.001). According to these regressions, a loss of 0.2 L/24 hours in UV leads to a loss of 0.15 weekly in Kt/VU and 11.3 L/1.73 m2 weekly in corrected CCrU (approximately 8 L/1.73 m2 weekly in corrected CCrU). By multiple linear regression, (1) Kt/VU = -0.38 + 0.70 (UV) + 0.10 (U/PUr). Standardized coefficients were 0.72 for UV and 0.51 for U/PUr (2) CCrU = -33.36 + 59.83 (UV) + 3.63 (U/PCr). Standardized coefficients were 0.65 for UV and 0.61 for U/PCr. UV is the most important determinant of both urea and creatinine urinary clearances in CPD patients. The contribution of the U/P ratios to the urinary clearances is important, but less than that of UV. The primary dependence of urinary clearances on UV allows the use of UV, which can be easily monitored by patients, as a first approximation index of changing residual renal function in CPD.

To study whether or not continuous peritoneal dialysis (CPD) can provide acceptable levels of normalized urea and creatinine clearance in heavyweight individuals.Retrospective analysis of urea and creatinine clearance studies.CPD patients followed in four dialysis units in Albuquerque, two dialysis units in Thessaloniki, and two dialysis units in Athens.One hundred and ninety-nine patients on CPD with 266 clearance determinations between 1991 and 1995.The heavyweight group consisted of 22 patients (24 clearance studies) weighing 100 kg or more (109 +/- 8.7 kg) at the time of the clearance study. All subjects were obese. The reference group consisted of 177 CPD subjects (242 clearance studies) of normal weight (68.7 +/- 12.2 kg). Urea fractional clearance (KT/V) and normalized creatinine clearance (Ccr) were compared between the heavyweight and the reference groups.The lowest acceptable weekly levels were set at 1.70 for KT/V and 54.4 L/1.73 m2 for Ccr.Weekly KT/V was 1.75 +/- 0.41 in the heavyweight group and 1.94 +/- 0.52 in the reference group (p = 0.047). Corresponding weekly Ccr levels were 64.0 +/- 24.3 and 77.6 +/- 40.3 L/1.73 m2, respectively (p = 0.021). In the heavyweight group, 13 studies (54.2%) had acceptable KT/V values compared to 160 studies (66.1%) in the reference group (NS). Corresponding values for acceptable Ccr were 17 (70.8%) and 165 (68.2%), respectively (NS). Drain volume was 12.96 +/- 4.40 L/24 hours in the heavyweight group and 9.63 +/- 2.58 L/24 hours in the reference group (p = 0.001). High daily exchange volume was delivered by a combination of daily continuous ambulatory peritoneal dialysis (CAPD) and nocturnal automated peritoneal dialysis (APD) in 13/16 heavyweight studies. This combination was tolerated better than any other method of delivering a large daily exchange volume.Although normalized urea and creatinine clearances are lower in obese, heavyweight individuals than in lean CPD subjects with lower weight, approximately equal percentages of these two groups achieve acceptable clearance levels. However, heavyweight individuals require larger-than-usual daily exchange volumes. The preferred way to deliver these large dialysate volumes is a combination of daily CAPD and nocturnal APD.

The expression (Estimated-Predicted)/Predicted creatinine generation ¿(E-P)/P¿ has been proposed as an index of compliance in continuous peritoneal dialysis (CPD). We attempted to define an (E-P)/P value that can be used as a cut-off for non-compliance and to characterize the relation of (E-P)/P to serum albumin. In 324 clearance studies, (E-P)/P had a normal distribution with a mean of +0.094 and an SD of 0.357. In these studies, there was a weak correlation between (E-P)/P and serum albumin (r = 0.12, P0.05), but (E-P)/P was not a predictor of serum albumin by logistic regression. In 34 CPD patients, who had an increase in the dose of CPD resulting in an increase in measured creatinine clearance from 43.8 +/- 14.0 to 66.1 +/- 17.6 L/1.73 m2 weekly (P0.001), (E-P)/P increased correspondingly from +0.018 +/- 0.284 to +0.153 +/- 0.369 (P = 0.018), although all subjects should be in a steady state of creatinine excretion in the second study. The rise in (E-P)/P was statistically significant in the subgroup of 17 subjects who had a decrease in serum albumin, but not in the subgroup of 14 subjects who had an increase in serum albumin from the first to the second clearance study. The (E-P)/P cut-off for a definitive diagnosis of CPD non-compliance may be around +0.400 or +0.500. The findings of this study suggest that non-compliance, as indicated by (E-P)/P, has an adverse effect on serum albumin and that non-compliance increases after a prescribed increase in the dose of CPD.

To compare estimates of urea volume (V) and KT/V obtained by the Watson and Hume anthropometric formulas, and to identify the similarities and differences between these estimates.Theoretical analysis applying wide variations in the determinants of anthropometric V (age, height, weight) in hypothetical women and men. Analysis of urea kinetic studies performed in patients on continuous peritoneal dialysis (CPD).Four dialysis units in Albuquerque, two in Athens, and two in Thessaloniki.Three hundred and two CPD patients who had 440 urea kinetic studies.Standard urea clearance was performed by 24-hour collections of urine and drained dialysate followed by blood sampling. V was estimated by both the Watson and Hume formulas.Estimates of V and KT/V were compared separately in women and men by Student's t-test, linear regression, and limits of agreement (mean difference +/- 2 SD). The agreement of the KT/V estimates was also tested by the kappa ratio using a value of 1.70 weekly as the lowest acceptable K/TV.The theoretical analysis indicated important disagreement only in extreme variations from the ordinary in height and, to a lesser extent, weight. Differences due to height variation were pronounced only in hypothetical women. CPD patient findings were as follows: in women, Watson V and weekly KT/V were 30.4 +/- 4.4 L and 2.10 +/- 0.61, respectively. Corresponding Hume estimates were 30.3 +/- 5.4 Land 2.1 2 +/- 0.66, respectively. Corresponding estimates for men were 40.5 +/- 5.7 L and 1 .92 +/- 0.57 (Watson) plus 41.4 +/- 5.6 L and 1.88 +/- 0.57 (Hume), respectively. By linear regression, KT/V(Hume) = -0.083 + 1.052 (KT/V(Watson)), r = 0.961 (women); and KT/V(Hume) = -0.026 +/- 0.992 (KT/V(Watson)), r = 0.985 (men). Limits of agreement were -1.41 L and 2.10 L for V, and -0.15 and 0.14 weekly for KT/V. In 94.3% of the cases, KT/V(Watson) and KT/V(Hume) agreed (both1 .70 or both1 .70 weekly). Kappa ratio was 0.875 (excellent agreement). The concordant and discordant groups differed in height and degree of obesity, in agreement with the theoretical analysis.The Watson and Hume formulas provide similar estimates of V and KT/V in CPD patients. Differences may be noted only if women's height or, to a lesser extent, both sexes' weight is at a great variance with the ordinary values.

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).Analysis of all CCr studies performed in CPD patients over 40 months.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.One hundred and ninety-four patients representing almost the entire CPD population in Albuquerque.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).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.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.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.

Body composition determines body water content (the fraction body water/body weight). With developing obesity, body weight and body water increase, but body water content decreases. The anthropometric formulas for urea volume (body water) for Kt/V computations in nonamputated peritoneal dialysis subjects reflect this fundamental rule of body composition. However, the use of uncorrected anthropometric formulas in amputees provides body water content estimates inconsistent with the estimates of body composition obtained from nutritional assessment. Corrected estimates of urea volume can be obtained in three steps: (1) The non-amputated weight at the same body composition is computed by dividing the weight at the urea kinetic study (postamputation) by (1-the fractional weight loss from the amputation); (2) body water and body water content at this nonamputated weight are obtained from the appropriate anthropometric formula; (3) at the time of the urea kinetic study, post-amputation, body water is equal to the estimate of body water content obtained from step 2 times the body weight at the urea kinetic study. The corrected estimates of urea volume provide body water content values agreeing with the estimates from nutritional assessment.

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 ureaor = 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/Vor = 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/V1.70 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/Vor = 1.90, identified KT/V1.90 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.

The association between azotemic index dialyzer clearances and hematocrit was investigated in a 63-year-old dialysis-dependent man with acquired renal cysts. During 43 months of hemodialysis, hematocrit rose from 27.3 to 65.0 vol%, as a consequence of high serum erythropoietin levels. Concomitantly, dry weight also increased from 116.8 to 140.8 kg. Both hematocrit and dry weight correlated with: (a) urea reduction ratio, (b) creatinine reduction ratio (CRR), and (c) KT/V urea. All correlations were negative. Stepwise regression showed that only hematocrit was an independent correlate of the CRR (CRR = 0.662 - 007* Hct, R2 = 0.770); whereas, both hematocrit (Hct) and weight (W) were independent correlates of KT/V urea (KT/V = 2.070 - 0.005*Hct - 0.009*W,R2 = 0.721). In addition to creatinine clearance, urea clearance through the dialyzer is reduced by a rising hematocrit. The effect of hematocrit on urea clearance is relatively small. Therefore, it requires large changes in hematocrit in order to be detected.

COPD is a common and treatable disease. The prevention of COPD is as least as important as its treatment. It is the physician's responsibility to detect the presence of airways disease and to stabilize or reverse any acute pulmonary event. Through patient education, drug treatment, and rehabilitation, the physician can halt the progression of disease, restore the patient's functional capacity, and attain the highest quality of life.

To demonstrate the effects of amputation on the estimates of urea volume of distribution (V) and KT/V urea in continuous ambulatory peritoneal dialysis (CAPD) patients and to present a method for correcting the errors created by the uncorrected anthropometric formulas estimating V.(1) A mathematical analysis of the error and the correction proposed was performed. (2) Urea kinetic modeling with uncorrected and corrected estimates utilizing both the Watson and the Hume anthropometric formulas was performed in amputees on CAPD.Subjects were recruited from four dialysis units in one city: one Veterans Affairs unit, one university-affiliated unit, and two community units.Fourteen amputees on CAPD:12 with unilateral leg amputation and 2 with bilateral leg amputation, at the same length of the leg, were studied.Urea kinetic studies were performed in 24-hour drained dialysate and urine specimens.Uncorrected and corrected estimates of V and KT/V urea were compared to each other and to the predictions of the mathematical model. Body weights corresponding to uncorrected and corrected V estimates were compared to the actual body weights.(1) The mathematical model predicts that uncorrected estimates by the anthropometric formulas will falsely characterize unilateral amputees as leaner than they are and bilateral amputees as more obese than they are. (2) In unilateral amputees studied with the Watson formulas, uncorrected V was 0.546 +/- 0.023 L/kg and corrected V was 0.520 +/- 0.023 L/kg (p0.001). Corresponding weekly KT/V urea values were 1.97 +/- 0.14 and 2.07 +/- 0.14, respectively (p0.001). Similar results were obtained with the Hume formulas. In bilateral leg amputees studied with the Watson formulas, uncorrected V was 0.479 +/- 0.022 L/kg and corrected V was 0.514 +/- 0.023 L/kg. Corresponding KT/V estimates were 2.11 +/- 0.45 and 1.96 +/- 0.14, respectively. The differences were even greater with the Hume formulas. Estimates of body weight calculated from corrected V values were equal to actual weight measurements, whereas those calculated from uncorrected V values were lower than actual body weight measurements in unilateral amputees, and much higher than actual body weight measurements in bilateral amputees.Uncorrected anthropometric estimates falsely characterize unilateral amputees as leaner than they actually are and bilateral amputees, amputated at the same leg length, as more obese than they actually are. Uncorrected KT/V estimates are, therefore, falsely low in unilateral amputees, and falsely high in bilateral amputees. The proposed correction of the anthropometric formulas provides estimates agreeing closely with dietary estimates of body composition. Further studies are needed to define the accuracy of the corrected formulas.

Peritonitis is a common problem for patients receiving continuous ambulatory peritoneal dialysis. Episodes that do not respond to antibiotics within 96 hours are associated with substantial morbidity and mortality. The purpose of this study was to develop a method for identifying these patients at the time of hospital admission.We reviewed all cases of peritonitis associated with continuous ambulatory peritoneal dialysis that occurred at the Albuquerque (NM) Veterans Affairs Medical Center during a 10-year period. Episodes of peritonitis were randomly assigned to a training set or a validation set. Persistent infections were those lasting more than 96 hours. For training cases, stepwise logistic regression was used to develop a predictive model for persistent infection using information available at the time of hospital admission. The model was then used to assign validation cases to "high-" and "low-risk" categories. The group difference in the proportion of persistent cases was tested by chi 2 analysis.Sixty patients had 120 episodes of peritonitis during the study period. Of 63 episodes assigned to the training set, 26 (41.3%) lasted more than 96 hours (persistent cases) and 37 were cured in 96 hours or less (usual cases). Compared with usual cases, persistent episodes were characterized by a higher age at presentation and a greater decline from preinfection values for hemoglobin and serum potassium, serum urea nitrogen, creatinine, albumin, and calcium. Advanced age and marked declines in serum potassium and albumin levels were identified by logistic regression as independent risk factors for persistent infection. The model identified 28 of 57 validation cases as high risk. Compared with low-risk cases, these episodes were much more likely to be persistent (64.3% vs 24.1%; P = .002) and result in death (32.1% vs 3.4%; P = .005).Advanced age and marked declines in serum albumin and potassium levels are poor prognostic signs in peritonitis associated with continuous ambulatory peritoneal dialysis. Patients with these findings should be treated aggressively.

This study was conducted to determine the association between glycemic control and clinical outcomes of diabetic patients maintained on chronic dialysis. The study group consisted of 226 diabetics (60 Type I and 166 Type II) classified as having either good glycemic control (50% of blood glucose determinations within 3.3-11.1 mmol/L) or poor glycemic control (50% of blood glucose measurements3.3 and11.1 mmol/L). The following variables were analyzed in each group: demographics; vascular and diabetic complications; laboratory values; and patient survival. In comparison to diabetics with poor control (Type I, n = 44; Type II, n = 57), those with good control, either Type I (n = 16), or Type II (n = 109), were dialyzed for longer periods and had shorter hospitalizations, lower prevalence rates of myocardial infarctions, congestive heart failure, orthostatic hypotension, gastroparesis and enteropathy, and higher mean serum albumin. Mean patient survival by life-table analysis was as follows: Type I diabetics, good control 128.9 + 8.1 months, poor control 29.5 + 5.0 months, p = 0.0014. Type II diabetics, good control 56.9 + 6.8 months, poor control 22.8 + 4.6 months, p0.0001. Good glycemic control during the first 6 months of dialysis predicted long-term survival for Type II but not for Type I diabetics. Poor glycemic control is associated with increased morbidity from vascular and diabetic complications, malnutrition, and shortened survival in diabetics on chronic dialysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adequacy of continuous ambulatory peritoneal dialysis (CAPD) and its variants is assessed by clinical outcomes, biochemical parameters and clearance parameters. Clinical outcomes lack specificity and probably sensitivity. Nevertheless, they constitute the "gold standard" to which any other method assessing dialysis adequacy must be compared. Biochemical parameters are both non-sensitive and non-specific and cannot be used to assess dialysis adequacy. Clearance of small molecular weight azotemic substances (urea, creatinine) presents considerable computational problems and interpretative difficulties. In preliminary studies, clearance studies have been able to differentiate between peritoneal dialysis patients having symptoms of inadequate dialysis and those clinically adequately dialyzed. Among population outcomes (morbidity, maintenance of peritoneal dialysis for long periods, hospitalization rate, mortality), only mortality seems to be associated with low clearances in retrospective studies. Prospective multicenter studies comparing clearance values to clinical outcomes are needed to evaluate clearance studies as methods of assessing peritoneal dialysis adequacy.

Clinical features, diagnosis and outcomes of persistently positive dialysate culture (PPDC) after apparent cure of continuous ambulatory peritoneal dialysis (CAPD) peritonitis were investigated in 16 PPDC episodes observed in 16 elderly (age 62 +/- 8 years) men who had been on CAPD for 14 +/- 9 months. Seven patients (46.7%) were diabetic. Peritonitis was caused by S. aureus in 14 cases and S. epidermidis in 2 cases. Preexisting or simultaneous infectious foci were present in 15 cases, exit-site infection in 5, tunnel infection in 13, and intra-abdominal abscess in 2 cases. Indium scans were positive in 6/9 cases (67%). Two patients died with the peritoneal catheter in situ, one from intercurrent myocardial infarction and one from S. aureus sepsis with pneumonia. In another 14 cases the peritoneal catheters were removed because of either tunnel abscess (8 cases) or peritonitis recurrence (6 cases). PPDC following apparent cure of CAPD peritonitis is almost always associated with exit-site, tunnel, or intra-abdominal abscess and leads invariably to catheter loss. Associated mortality is substantial.

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) if50% oror = 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 (p0.0001). Technique survival was 14 +/- 2 months for group P and 28 +/- 4 months for group G (p0.0001). Good diabetic control in diabetics on CAPD is associated with better outcome and constitutes, therefore, a desirable therapeutic goal.

Features helpful in diagnosis and associated with death were evaluated in 26 episodes of peritonitis associated with intra-abdominal pathology (IAP) in continuous ambulatory peritoneal dialysis (CAPD) patients. Culture of multiple enteric pathogens, or of a single unusual enteric pathogen, from the dialysate was useful for diagnosis in 22/26 instances. Other diagnostic features (fecal material in dialysate, diarrhea containing dialysate, increasing free air in the abdominal cavity) were infrequently found. A comparison of patients who died (n = 11, 42%) and those who survived revealed that death was associated with bowel gangrene (5/6 died), recovery of bacteroides from the dialysate, more frequent and severe comorbid conditions (bacteremia, pneumonia, intra-abdominal and intracerebral bleeding, septic shock, hepatic failure), the development of severe malnutrition and thrombocytopenia during infection, and multiple surgical procedures until the diagnosis was established. Peritonitis associated with intra-abdominal pathology in CAPD patients is a severe infection with considerable diagnostic difficulty and high mortality. Early exploratory laparotomy upon suspicion of the nature of the peritonitis, usually raised by the recovery of enteric pathogens from the dialysate, may improve mortality.

Clinical and biochemical parameters associated with the removal of the peritoneal catheter and death following continuous ambulatory peritoneal dialysis (CAPD) peritonitis were analyzed in 120 episodes of peritonitis. Episodes resulting in catheter removal (n = 24, 20%) and those ending in patient death (n = 12, 10%) were respectively compared with episodes in which peritoneal catheters were saved and from which the patients survived. Variables associated with catheter removal included advanced age, long duration of peritonitis, coexisting exit-site/tunnel infection, infection caused by pseudomonas or fungi, elevated aspartate aminotransferase (AST) and malnutrition at presentation with peritonitis (serum albumin 29.5 +/- 7.6 g/L vs 33.8 +/- 4.8 g/L in episodes in which the catheters were saved, p = 0.014), and worsening malnutrition during peritonitis. Variables associated with death from peritonitis included diabetes mellitus, persistence of the infection, removal of the peritoneal catheter, infection with pseudomonas, malnutrition prior to the infection (serum albumin 29.5 +/- 3.2 g/L vs 34.7 +/- 4.2 g/L in survivors, p0.001), presentation with elevated AST and worsening malnutrition, and the development of pronounced malnutrition during infection (serum albumin 18.1 +/- 4.1 g/L vs 28.9 +/- 5.8 g/L in survivors, p0.001). Deaths were caused primarily by cardiovascular events. Both removal of the peritoneal catheter and death as consequences of CAPD peritonitis are associated with malnutrition and pseudomonas infection. In addition, death is more frequent in diabetic patients.

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.

Changes in 10 metabolic parameters (body weight, blood hemoglobin, and serum albumin, urea, creatinine, cholesterol, triglycerides, potassium, calcium and phosphorus) were compared in 28 episodes of routine peritonitis and 27 episodes of persistent peritonitis. These infections occurred in 20 CAPD patients, all of whom acquired both types of peritonitis on separate occasions. Coagulase-negative staphylococci predominated in the routine infections, while Staphylococcus aureus and Gram-negative bacilli, especially Pseudomonas, were associated with persistent peritonitis. Decreases during infection were significantly larger in persistent as compared with routine peritonitis episodes for all 10 nutritional parameters. Time required for recovery of all nutritional variables except serum potassium and urea was significantly longer in the persistent episodes. Persistent peritonitis led to peritoneal catheter loss in 13 of the 27 episodes and was associated with 4 deaths, while routine peritonitis was associated with neither catheter loss nor death. In contrast to routine peritonitis, persistent CAPD peritonitis is associated with severe malnutrition, considerable morbidity, and mortality.

To develop a method for predicting hospital admissions for patients with decompensated chronic obstructive pulmonary disease treated in an emergency department.A 4-year survey including training and validation periods was conducted. Stepwise logistic regression was used to develop a multivariate model using information from the patient's previous visits and results of baseline pulmonary function tests.During the first 2 years, there were 693 visits to the emergency department for decompensated chronic obstructive pulmonary disease. The patient was admitted to the hospital on 210 occasions (30.3%). Logistic regression showed that the probability of admission was related to the following: the admission and relapse rates for previous visits, the proportion of previous discharges from the emergency department in which "conservative therapy" was given, the highest baseline post-bronchodilator forced expiratory volume in 1 second within 3 years of entry, and the highest baseline pre-bronchodilator forced expiratory volume in 1 second-vital capacity ratio. A relapse was defined as an unscheduled return to the emergency department within 48 hours. "Conservative therapy" was any treatment regimen that did not include parenteral medications. During the next 2 years, the model was validated with patients not previously treated at this medical center. Seventy-six (28.3%) of 269 episodes resulted in hospital admission. The logistic model was used to categorize each visit during the validation phase. "High-risk" visits had calculated probabilities of admission greater than .208, while "low-risk" visits had values that were less. The admission rate for 98 low-risk visits (8.2%) was much lower than the rate for 171 high-risk visits (39.8%).A multivariate model can be used to identify patients with decompensated chronic obstructive pulmonary disease who are unlikely to need hospitalization. This model could be used to select episodes of decompensated chronic obstructive pulmonary disease for treatment at home.

To develop and validate a multivariate model for predicting relapses after treatment of decompensated chronic obstructive pulmonary disease in an emergency department.A 5-year survey was conducted, including training and validation periods. Stepwise logistic regression was used to develop a multivariate predictive model using clinical data obtained at the time of each visit. A relapse was defined as an unscheduled return to the emergency department within 48 hours. SITE: The study was conducted in the emergency department of the Albuquerque (New Mexico) Veterans Affairs Medical Center.The subjects were 289 patients with documented chronic obstructive pulmonary disease.During the first 3 years, there were 705 visits in which the patient was treated and released from the emergency department. Relapse occurred 82 times (11.6%). Logistic regression showed that the following variables had an effect on the risk of relapse: the relapse rate for previous visits, a previous visit within 7 days, long-term home oxygen therapy, the number of doses of nebulized bronchodilators, the administration of aminophylline, and the use of antibiotics and prednisone at the time of discharge from the emergency department. During the next 2 years, the 48-hour relapse rate was 9.9% (47 of 476 discharges). When the model was fitted to these data, all of the original variables contributed to the prediction of relapse except antibiotic use and long-term home oxygen therapy. The logistic model was used to categorize each visit during the validation phase. The relapse rate for "high-risk" visits was significantly higher than that for "low-risk" visits (18.4% vs 6.1%). The method identified 57.4% of visits that ended in relapse at 48 hours.A multivariate model can be used to identify patients with a poor prognosis after the outpatient treatment of decompensated chronic obstructive pulmonary disease.

To determine whether any potentially reversible variables are related to the development of hand gangrene in diabetic patients on dialysis, the authors compared 15 patients with hand gangrene (group A) to three control groups of diabetics on dialysis: 20 patients with foot gangrene (group B); 31 patients without gangrene of the extremities (group C); and 20 patients without hand arterial calcifications (group D). All patients in groups A-C had medial arterial calcifications of the hands. Group A patients started dialysis at an earlier age (p less than 0.05), were treated for end-stage renal disease (ESRD) for a longer time period (p less than 0.05), and had a lower mean serum albumin concentration during the dialysis period (p less than 0.05) than the patients in the control groups. Hand gangrene also appeared to be associated with the presence of a functioning arterio-venous fistula in the extremity with the gangrene, with loss of function of renal transplant, and with hyperaluminemia. Other variables, including serum parathormone, were not different for the four groups. Logistic regression showed that the following were risk factors for hand gangrene: hypoalbuminemia, long duration of ESRD treatment, hyperphosphatemia, high insulin dose, hypercholesterolemia, and hypoglycemia. In diabetics on dialysis, gangrene develops in hands with medial arterial calcifications, but does not correlate with measures of calcium or phosphorous metabolism. Predictors of hand gangrene include certain potentially reversible clinical and biochemical variables.

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.

A total of 146 patients, 91 on chronic hemodialysis and 55 on chronic peritoneal dialysis, were asked to declare their choice of cardiopulmonary resuscitation (CPR) in cases of cardiopulmonary arrest. Fifty-four patients (37%) declined CPR. The severity of medical disability and the presence of diabetes were independent predictors of refusal of CPR. The pattern of patient reaction to CPR gave valuable information about patients' comprehension of this issue and about patients' ability to cope emotionally with CPR. On the basis of the reaction pattern, approximately 95% of the patients interviewed understood CPR and reacted to it appropriately. Questioning dialysis patients about their CPR preference is feasible and fruitful.