Περίληψη:
The purpose of the present study was to assess the mechanical behavior
of the respiratory system separately during inspiration and expiration
in adult respiratory distress syndrome (ARDS) and the influence of PEEP
on any phasic variations of the mechanical respiratory parameters.
Airways pressure (P), flow (V), and volume (V) signals were recorded in
nine patients with ARDS and 10 patients without known respiratory
disorder (control group). All patients were artificially ventilated at
three levels of positive end-expiratory pressure (PEEP): 0, 5, and 10
hPa. Data were analyzed separately for inspiratory and expiratory
records using multiple linear regression analysis (MLRA) according to
the equation: P=Ers V + Rrs V’ + P-0, where Ers and Rrs represent,
respectively, the intubated respiratory system elastance and resistance,
and P-0 the end-expiratory pressure. In the ARDS group expiratory Ers
(Ers(EXP)=45.58 +/- 4.24 hPa/L) was substantially higher (p < 0.01) than
inspiratory Ers (Ers(INSP)=36.76 +/- 2.55) with a marked effect of
applied PEEP in diminishing the difference between Ers(EXP) and
Ers(INSP) (P < 0.01). For the ARDS group inspiratory Rrs (Rrs(INSP))
decreased significantly with increasing PEEP (PEEP=0: Rrs(INSP)=1643,
PEEP=10: Rrs(INSP)=13.28, p < 0.01). The found differences between
Ers(EXP) and Ers(INSP) could be attributable to an influence of
mechanical ventilation by positive airway pressure on pulmonary edema
and interstitial fluid during the inspiratory phase of the respiratory
cycle. (C) 2002 Elsevier Science Ltd, All rights reserved.
Συγγραφείς:
Frantzeskaki, F
Amygdalou, A
Rasmussen, TR
Vassiliou, MP and
Behrakis, PK
