Nephrology S., Pneumology S.*.General Yagüe Hospital. Burgos. Spain.

INTRODUCTION: Patients with chronic renal failure can present muscular weakness of uncertain etiology, involving proximal muscles and so respiratory muscles. To evaluate respiratory muscle force, maximal respiratory pressures (P.max.), both inspiratory (MIP) and expiratory (MEP), were measured and we try to investigate the influence of hemodialysis (Hd.) sessions and find a relations between diverses dialysis parameters and respiratory muscular weakness.

PATIENTS AND METHODS: 24 patients in chronic Hd. program were admitted to the study. Patients with more than 70 years old, chronic obstructive pulmonary disease (COPD), cardiorepiratory disease, neuromuscular patology and diabetes mellitus were excluded. The mean was 51.00± 13.36 and the median duration of Hd. was 70 months. Hemoglobin (Hb), hematocrit (Htº), ferritin, albumin, calcium, phosphorus, parathiroid hormone (PTH), body mass index (BMI),ultrafiltration rate and arterial pressures during Hd. sessions and parameters derivated of Urea Kinetic Modeling (UKM): protein catabolism rate (PCR) and Kt/V were determinated. SIBELMED 163 gauge was utilized for MIP and MEP measuring before and after Hd. sessions. Peack expiratory flow (PEF) was also determinated by a standard peack-flow meter. Stadistical analysis was performed using Student's t test and Pearson's coefficient correlation. p value less than 0.05 was considered significant.

RESULTS: There were no significant differences in MIP and MEP meassures before and after Hd. sessions. When P.max obtenied values were compared with their theoretical values for age and sex were decreased: MEP 42.5± 37 (p<0.001; C.I. 95% 58;26), MIP: -26± 25 (P<0.001;C.I. 95%:37;15). A SIGNIFICANT DIFFERENCE WAS FOUND BETWEEN PEF MEASURES PRE AND POST HD.14.58± 24.95 (P=0.009; C.I.95%: 4.03;25.12). THERE WAS A DIRECT AND SIGNIFICANT DIFFERENCE BETWEEN PEF MEASURES BEFORE AND AFTER HD. AND ULTRAFILTRATION RATE DURING HD. SESSIONS; VARIATIONS IN ARTERIAL PRESSURE WERE NOT IMPLICATED IN THIS ISSUE. SIGNIFICANT AND DIRECT CORRELATION BETWEEN HB AND MIP AND MEP EXISTED. THERE WAS NO CORRELATION WITH KT/V, PCR, PTH, AND RESTING ANALYZED VARIABLES.

CONCLUSSIONS:

1. With respect to their theoretical meassures, Hd patients presented a low values of MIP and MEP, without influence by Hd sessions.
2.We found a significant and direct correlation between Hb concentration and decreased MIP and MEP measures.
3.There was a PEF improvement after Hd. sessions and this improvement was correlated with ultrafiltration rate.