Nm. Siafakas et al., RESPIRATORY MUSCLE STRENGTH DURING CONTINUOUS AMBULATORY PERITONEAL-DIALYSIS (CAPD), The European respiratory journal, 8(1), 1995, pp. 109-113
The purpose of this study was to investigate the effect of chronic ren
al failure (CRF) and continuous ambulatory peritoneal dialysis (CAPD)
on respiratory muscle function. Global respiratory muscle strength was
assessed by measuring mouth pressures during maximum static inspirati
on (PImax) near residual volume (RV) and expiration (PEmax) near total
lung capacity (TLC), in 26 patients. Maximum pressures, spirometry an
d lung volumes were measured before dialysis, 4 h after the administra
tion of 2 l of dialysate into the peritoneal cavity, and just after th
e next drainage. In addition, biochemical indices (urea, creatinine, s
odium, potassium, calcium and phosphorus) and haematological indices (
haemoglobin (Hb) and haematocrit (Hct)) were measured once before the
treatment. The results showed that mean PImax and PEmax were normal, w
ith a very wide range between patients, before CAPD. However, seven pa
tients (27%) showed a PImax of <75% predicted (pred) and eight (31%) a
PEmax <75% pred. Maximal pressures decreased significantly during CAP
D and increased again after the drainage of fluid. Similarly, lung vol
umes were within the normal range before and decreased significantly d
uring CAPD. The forced expiratory volume in one second to forced vital
capacity (FEV(1)/FVC) ratio did not change. We conclude that respirat
ory muscle strength was preserved in the majority of the patients with
chronic renal failure treated with CAPD. During CAPD, lung volumes an
d respiratory muscle function were decreased, demonstrating an effect
of the abdominal cavity on the mechanics of the respiratory system. Ho
wever, the decrease in the maximum pressures was less that 20%, indica
ting that CAPD is a safe procedure in patients without pre-existing pu
lmonary disease or uraemic pulmonary complications. Respiratory muscle
strength increased immediately after the drainage of fluid.