ISSN:
1432-1238
Keywords:
Monitoring
;
Gas exchange
;
Intensive care
;
CO2 ductances
;
Dead space
;
CO2 arterioalveolar gradient
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract A cardiorespiratory monitoring system allows the measurement of $$F\overline {AE_{CO_2 } } $$ and $$F\overline E _{CO_2 } $$ in the expired air of the patient at the mouth (endtidal CO2) and in a mixing box. From these parameters, combined with the measured $$Pa_{CO_2 } $$ , the alveoloexpired $$(DuA = P\bar E_{CO_2 } /P\overline {AE} _{CO_2 } ) $$ and alveolararterial $$(DuA = P\overline {AE} _{CO_2 } /Pa_{CO_2 } )$$ ductances which assimilate the respiratory system to a two-stage exchanger have brought about a lot of valuable information: 1. DuA improves by 20% in 20 patients after removal of bronchial obstruction (p〈0.001) and by 9% in 7 intubated patients after tracheotomy (p〈0.02). DuA falls by 15% (p〈0.001) in 10 patients with hypocapnia ( $$Pa_{CO_2 } $$ = 28 mmHg) after a dead space adjunction with the aim of normalizing $$Pa_{CO_2 } $$ ( $$Pa_{CO_2 } $$ = 35 mmHg). 2. Dua falls by 33% in six patients after pulmonary embolism, proved by angiography (p〈0.001) and by 9% in 34 patients after 30 min of pure oxygen breathing (p〈0.001). On the other hand, in the absence of clinical or radiological pulmonary edema, it increases by 19% in 38 patients with hypervolemia after diuresis (furosemide) (p〈0.001). Thus since $$DuA_{CO_2 } $$ varies with anatomical dead space and the air distribution disorder, $$DuA_{CO_2 } $$ evolves according to the disorders of the blood distribution and arterial-alveolar diffusion. The determination of these coefficients, in the absence of significant changes in the arterial blood gases, helps the diagnosis, guides the early treatment and allows for the monitoring of its efficiency.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01687162
Permalink
