Am. J. Respir. Crit. Care Med., Vol 153, No. 1, 01 1996, 458-461.
Effects of laparoscopic cholecystectomy on global respiratory muscle strength
N Rovina, D Bouros, N Tzanakis, M Velegrakis, S Kandilakis, F Vlasserou and NM Siafakas
Department of Thoracic Medicine, University General Hospital of Crete, University of Crete Medical School, Greece.
Laparoscopic cholecystectomy has a better postoperative outcome than the
traditional open technique, which has been shown to significantly affect
respiratory muscle function. The aim of this study was to investigate the
effects of laparoscopic surgery on respiratory function, and particularly
that of the respiratory muscles. Respiratory muscle strength was assessed
in 26 patients who underwent laparoscopic cholecystectomy and in 25 who
underwent open cholecystectomy by measuring mouth pressure during maximum
static inspiratory (PImax) and expiratory (PEmax) efforts. PImax, PEmax,
and blood gases were measured 24 h preoperatively (-24 h) as well as 24 h
(+24 h) and 48 h (+48 h) postoperatively. FEV1 and FVC were measured at -24
h and +48 hr, and the ratio of FEV1 to FVC (FEV1/FVC) was calculated. PImax
decreased at +24 h and +48 h in both groups, but this decrease was
significantly greater in the patients who had open surgery, (p < 0.01,
and p < 0.005, respectively). Similarly, PEmax was significantly smaller
in the open- than in the laparoscopic-surgery group (p < 0.0001) at +48
h. Spirometric indices showed a more severe restrictive defect at +48 h
after open surgery than after laparoscopy (p = 0.01). The arterial oxygen
tension (PaO2) was significantly greater in the laparoscopic- than in the
open-surgery group at +24 h (p < 0.007). Laparoscopic cholecystectomy
caused smaller decreases in respiratory muscle strength than did open
surgery. This accords with the hypothesis of phrenic nerve inhibition
during open surgery. The results are of clinical importance, since they may
explain the different outcomes with the two techniques.
