[The social environment of patients on peritoneal dialysis]. / El entorno social de los pacientes en diálisis peritoneal.

Patients suffering chronic illnesses, such as those on replacement therapy, condition and are conditioned by their family, work, and social environment. A continuous psychophysical impairment occurs and alters the hormonal stress mediators from the central nervous system and the hypothalamic-pituitary-adrenal axis. Such stress situation causes a pathological effect additional to the factors inherent to the disease. Psychological disorders (depression, anxiety, and others) are associated to an increased morbidity, directly acting upon treatment course, subsequent treatment failure, and personal perception of one's own state of health. Individual factors (sex, lifestyles, health and dietary habits, spirituality, financial and family situation, personal skills for coping with disease, cultural level, and social status) condition morbidity in these patients, and the course and complications of peritoneal dialysis. Interactions between healthcare staff and patients on peritoneal dialysis cause these patients to have a more active attitude and a greater involvement in their treatment, which has an impact on the course of disease and clinical status.

Our nine-year experience with the self-locating catheter: comparison of malfunction rate with other Tenckhoff catheter variants.

OBJECTIVE: To evaluate catheter-related complications among self-locating and other variants of Tenckhoff catheters. PATIENTS AND METHODS: We studied all self-locating catheters implanted in our hospitals from May/97 to Dec/05. We extended the follow-up to Jun/05. We collected demographic data, causes of catheter withdrawal and dropping of PD. We studied data about technique and catheter related complications. RESULTS: We included 328 catheters in 285 patients. There were 258 self-locating, 55 straight and 15 curled. There was a higher rate of catheter withdrawal due to malfunction in patients with straight or pig-tail catheters than in self-locating ones (log-rank, p < 0.001). CONCLUSION: In our patients, self-locating catheters have a lower malfunction rate than other variants of Tenckhoff catheters.

Lower malfunction rate with self-locating catheters.

OBJECTIVE: We analyzed malfunction rates (obstruction, omental wrapping, displacement) and catheter survival for self-locating catheters as compared with other Tenckhoff catheter designs. PATIENTS AND METHODS: We conducted our survey at two centers, prospectively studying all self-locating catheters implanted from May 1997 to October 2000 and used for peritoneal dialysis (PD). Tenckhoff catheters of other designs used previously in our units were used as the control group. We analyzed removal causes and catheter survival. RESULTS: We studied 173 catheters (105 self-locating catheters, 53 straight catheters, and 15 coiled catheters) implanted in 139 patients (43% of them women) with a mean age of 53 +/- 14 years. The analysis of catheter removal showed that 3 of 105 self-locating catheters, 3 of 15 coiled catheters, and 17 of 53 straight catheters were removed owing to malfunction (chi2: p = 0.0000). Kaplan-Meier curves showed that the bulk of removals for malfunction occurred within the first 3 months after PD start. The group of self-locating catheters showed better survival (log-rank: p = 0.0009). Other causes for catheter removal included peritonitis (n = 22), exit-site infection alone (n = 4), and end of PD treatment (n = 66). No significant differences were seen in the annual peritonitis rate (straight-tip: 0.955 +/- 2.315 episodes annually; coiled-tip: 0.651 +/- 0.864 episodes annually; self-locating: 0.720 +/- 1.417 episodes annually; t-test: p > 0.400). No gut or bladder perforations were observed. CONCLUSION: In our survey, self-locating catheters were associated with better survival and fewer removals for malfunction than were Tenckhoff catheters of other designs.

Prevention of intraocular pressure elevations during hemodialysis.

Intraocular pressure (IOP) may rise during hemodialysis sessions in predisposed patients because of a rapid drop in osmolality at the blood compartment. A patient with diabetes had painful ocular episodes during hemodialysis that were associated with an IOP increase. We modified the dialysis parameters to prevent a rapid decrease in osmolality by creating conductivity and ultrafiltration profiles and adding a colloid solution at the beginning of the procedure. After instituting these changes, the patient became asymptomatic and did not have variations in IOP during the dialysis sessions.

Ambulatory blood pressure monitoring and diagnostic errors in hypertension: a Bayesian approach.

Random variability of blood pressure complicates the diagnosis and subsequent treatment of hypertension. To evaluate the importance of the number of blood pressure measurements in the correct diagnosis and control of hypertension, the authors used a Bayesian model to estimate the true average blood pressure of a group of newly diagnosed hypertensives, then calculated the diagnostic error that would result from monitoring methods using 24 daytime measurements or from using only three random monitoring measurements. The study population consisted of 129 individuals with newly diagnosed mild hypertension according to standard criteria, who were also evaluated with an ambulatory blood pressure monitor. In true normotensives (daytime diastolic blood pressure <90 mm Hg), the negative predictive value with three measurements was 0.92, and it rose to 0.96 with monitoring methods. In mild hypertensives (90-104 mm Hg), the positive predictive value was 0.64 with three measurements and 0.84 with monitoring methods, thus reducing the rate of false mild hypertensives from 35% to 15%. Finally, in patients with moderate or severe hypertension (>104 mm Hg), the positive predictive value improved from 0.26 with three readings to 0.61 with monitoring methods. Similar results were observed with daytime systolic pressure measurements. As the number of measurements increased, the diagnostic error due to the random variability of blood pressure became progressively smaller. In cases of hypertension, the large improvement in predictive values may justify using monitoring methods to confirm standard diagnosis.

[Tubular changes in renal polycystosis in adults]. / Alteraciones tubulares en la poliquistosis renal del adulto.

Fifteen (15) patients diagnosed of adult renal polycystosis with normal renal function (creatinine clearance) greater than 80 cc(min/1.73 m2 c.s.) were studied in order to assess distal renal tubular functioning. We observed a great variation in the data obtained, 6 patients with disorders in the concentration capacity (40%); 5 patients (33%) with defects in ammoniogenesis and in net excretion of acids; 3 patients (20%) with isolated ammoniogenesis defects and 6 patients (40%) without any functional disorder. Given that there were patients (6) without distal tubular disorders, these studies should not be used as diagnostic method of adult renal polycystosis.