Endotracheal tube cuff pressure assessment maneuver induces drop of expired tidal volume in the postoperative of coronary artery bypass grafting.
BACKGROUND
Previous investigations reported that the cuff pressure (CP) can decrease secondary to the CP evaluation itself. However is not established in literature if this loss of CP is able to generate alterations on expired tidal volume (ETV). Therefore, the aim of this study was to evaluate the potential consequences of the endotracheal CP assessment maneuver on CP levels and ETV in the early postoperative of coronary artery bypass grafting (CABG).


METHODS
A total of 488 patients were analyzed. After the operation, the lungs were ventilated in pressure-assist-control mode and the same ventilatory settings were adjusted for all patients. After intensive care unit arrival, the cuff was fully deflated and then progressively inflated by air injection, to promote a minimal volume to occlude the trachea. To assist the cuff inflation and the air leakage identification, the graphical monitoring of the volume-time curve was adopted. After 20 minutes a first cuff pressure evaluation was performed (P1) and a second measurement (P2) was taken after 20 minutes with an analog manometer. ETV was obtained always pre and post P1 measurement.


RESULTS
The CP assessment maneuver promoted a significant drop of P2 in relation to P1 when the manometer was attached to the pilot balloon (p < 0.0001). When compared the moments, pre-P1 versus post-P1, a significant drop of the ETV was also observed (p < 0.0001).


CONCLUSIONS
The CP assessment maneuver promoted a significant decrease in CP values and occurrence of air leakage with reduction of ETV in the early postoperative of CABG.
Department of Medicine, Cardiology Discipline, Pirajussara and São Paulo Hospitals, Escola Paulista de Medicina, Federal University of Sao Paulo, Napoleao de Barros, 715, Sao Paulo 04024-002, Brazil.
Douglas W
DW
Bolzan
Solange
S
Guizilini
Sonia M
SM
Faresin
Antonio Cc
AC
Carvalho
Angelo Av
AA
De Paola
Walter J
WJ
Gomes
D000368:Aged; D001026:Coronary Artery Bypass / Q000379:methods*; D045853:Exhalation / Q000502:physiology*; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008365:Manometry / Q000009:adverse effects / Q000379:methods*; D008875:Middle Aged; D011312:Pressure; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000295:instrumentation / Q000379:methods; D013990:Tidal Volume / Q000502:physiology*