Lung recruitment maneuver depresses central hemodynamics in patients following cardiac surgery.
OBJECTIVE
To assess the impact of the lung recruitment maneuver on circulation following cardiac surgery.


METHODS
Prospective randomized cross-over study at the Departments of Anesthesia and Thoracic Surgery, Copenhagen University Hospital.


METHODS
Ten adult undergoing coronary artery bypass surgery.


METHODS
Patients were randomized to two durations of lung recruitment maneuvers (40 cmH2O airway pressure for 10 s and 20 s or vice versa after 5 min) administered immediately after surgery.


RESULTS
Transesophageal echocardiography (left ventricular short axis view), pulse contour cardiac output, and arterial blood pressure were monitored continuously. Systemic and pulmonary arterial blood gases were sampled before and after each lung recruitment maneuver to calculate the intrapulmonary shunt. Left ventricular end-diastolic areas decreased significantly during both the 10-s and the 20-s lung recruitment maneuvers. Cardiac output was 5.6+/-0.8 l/min at baseline, decreasing by 3.0+/-1.1 l/min and 3.6+/-1.2 l/min during lung recruitment maneuvers of 10 and 20 s, respectively. Shunt decreased from 20+/-5% to 15+/-6% after the first lung recruitment maneuver and from 15+/-6% to 12+/-5% after the second.


CONCLUSIONS
Lung recruitment maneuvers markedly reduced cardiac output and left ventricular end-diastolic areas in hemodynamically stable patients following cardiac surgery.
Nielsen
Jonas
J
Department of Anesthesia and Intensive Care Medicine, Copenhagen University Hospital Gentofte, Niels Andersens Vej 64, 2900 Hellerup, Denmark. Jonie@gentoftehosp.kbhamt.dk
Østergaard
Morten
M
Kjaergaard
Jesper
J
Tingleff
Jens
J
Berthelsen
Preben G
PG
Nygård
Eigil
E
Larsson
Anders
A
D000368:Aged; D002302:Cardiac Output; D001026:Coronary Artery Bypass; D017548:Echocardiography, Transesophageal; D005260:Female; D006339:Heart Rate; D006801:Humans; D008170:Lung Compliance / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period