Anest. intenziv. Med. 2006;17(4):208-212

Impact of the opening manoeuvre on gas exchange, haemodynamics and the splanchnic circulation in ARDS patientsIntensive Care Medicine - Original Paper

V. Zvoníček, V. Šrámek

Anesteziologicko-resuscitační klinika, Lékařská fakulta Masarykovy univerzity a Fakultní nemocnice u sv. Anny v Brně

Objective:
To perform the recruitment manoeuvre (RM) in ARDS patients according to transalveolar pressure (Ptrans = airway pressure minus oesophageal pressure) and to evaluate its impact on gas exchange and the global and splanchnic haemodynamics.

Design:
Prospective, interventional study.


Setting:
Department of Anaesthesia & Intensive Care, St. Anna University Hospital, Brno, Czech Republic.

Methods:
Patients in the early phase of ARDS were enrolled in the study. RM was performed in the CPAP mode for 40 seconds; the aim was to reach transalveolar pressure (Ptrans) of 30 cm H₂O measured by a special bedside respiratory monitoring system.The haemodynamics and blood gases from the pulmonary, radial and hepatic arteries were measured 2 minutes before (preOM), and 2 and 30 minutes after the RM (OM2, OM30). Friedman ANOVA was used for statistical analysis. The data are presented as median and interquartile range.

Results:
Nine ARDS patients were included. During the RM, CPAP of 50 (49-53) and 24 (20-25) cm H₂O was used. Ptrans was reached. MAP decreased by 33% (7-61%) during the RM (P < 0.001). Other haemodynamic parameters were not statistically significantly different except for an increase in the cardiac index (CI) from 3.8 (3-4.3) preOM to 4.4 (3.2-5.1). Oxygenation did not improve during the RM. The PaO₂/FiO₂ index was 193 (163-199), 195 (166-195) and 165 (154-199) preOM, OM2 and OM30 respectively, P = 0.54. A significant increase in PaCO₂ to 4.8 (4.0-5.2) and 4.9 (4.5-5.5) kPa was observed after the RM (P = 0.02, P = 0.05). The difference in oxygen saturation between the pulmonary and hepatic arteries (SvO₂-ShO₂) also did not change: 15.3 (8.7-24.1), 18.8 (12.6-23.3), 22.9 (14.0-30.6) at preOM, OM2 and OM30 respectively (P = 0.23).

Conclusion:
During the RM the transalveolar pressure of 30 cm H₂O was not reached in any patient. The RM caused a temporary but significant MAP decrease and did not change oxygenation or the splanchnic circulation.

Keywords: ARDS; recruitment manoeuvre; haemodynamics; splanchnic circulation

Published: August 1, 2006  Show citation