[Effect of isoflurane on gas exchange and systemic and pulmonary hemodynamics in man during single lung ventilation].
OBJECTIVE
We studied the effect of 1.5% isoflurane end expiratory fraction on arterial oxygenation and on systemic and pulmonary hemodynamics during nonsurgical single lung ventilation.


METHODS
The study includes 6 patients undergoing surgical thoracotomy. In all cases a double lumen endotracheal tube was inserted and pulmonary ventilation was performed with a FiO2 = 1. Patients were placed on lateral decubitus position. The following variables were measured: mean arterial pressure (MAP), mean pulmonary artery pressure (MPAP), central venous pressure (CVP), capillary pulmonary pressure (CPP), cardiac output (CO), and Qs/Qt. Measurements were taken at three different situations. The first was done under bilateral pulmonary ventilation and intravenous anesthesia with thiopental, fentanyl, and diazepam. The nondependent lung was collapsed by means of a selective ventilation of the dependent lung, and the second series of measurements was done 20 min after intravenous anesthesia. The third block of data was obtained after 15 min of respiratory ventilation with 1.5% isoflurane.


RESULTS
Single lung ventilation induced a significant decrease of Pa O2 (379 +/- 96 mmHg vs 208 +/- 93 mmHg) and a significant increase in Qs/Qt (20 +/- 8% vs 30 +/- 10%). However, during isoflurane ventilation there were no significant changes in PaO2 (208 +/- 93 mmHg vs 204 +/- 94 mmHg) nor in Qs/Qt (30 +/- 10 vs 28 +/- 8). Isoflurane elicited a significant decrease of the CO, whereas MPAP, RVS, and PvO2 did not show significant variations.


CONCLUSIONS
We conclude that 1.5% isoflurane end expiratory concentrations did not significantly affect pulmonary oxygenation during single lung ventilation.
Solares
G
G
Departamento de Anestesia y Reanimación, Hospital Universitario Valdecilla, Santander.
Castro
A
A
Villanueva
M
M
García-Izquierdo
M
M
Buitrago
P M
PM
D000368:Aged; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D007530:Isoflurane / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D011652:Pulmonary Circulation / Q000187:drug effects*; D011659:Pulmonary Gas Exchange / Q000187:drug effects*; D012121:Respiration, Artificial / Q000379:methods
D007530:Isoflurane
Efecto del isoflurano sobre el intercambio gaseoso y la hemodinámica sistémica y pulmonar en el hombre durante la ventilación a un solo pulmón.