Effects of isoflurane on regional pulmonary blood flow during one-lung ventilation.
Isoflurane has been reported to inhibit hypoxic pulmonary vasoconstriction. However, the effects of one-lung ventilation and isoflurane on regional pulmonary blood flow (Qr) have not been investigated in detail. Therefore, using radionuclide labelled microspheres we measured Qr in rabbits (n = 8) in the left lateral decubitus position during two- and one-lung ventilation under i.v. baseline anaesthesia and during additional administration of 1.5% isoflurane. Macrohaemodynamic variables were recorded continuously. Isoflurane increased non-dependent lung blood flow during two-lung ventilation. One-lung ventilation caused a homogeneous decrease in Qr throughout the hypoxic lung, irrespective of isoflurane administration (P < 0.001). However, isoflurane significantly augmented Qr of the hypoxic lung during one-lung ventilation (P < 0.05). During all phases, Qr of the upper lobe was higher compared with that in the lower lobe in isogravitational slices of both lungs; a ventrodorsal perfusion gradient was found in the left upper lobe. We conclude that 1.5% isoflurane increased perfusion of the non-dependent lung, inhibited hypoxic pulmonary vasoconstriction-induced redistribution of pulmonary blood flow and did not influence isogravitational perfusion gradients.
Groh
J
J
Institute of Anaesthesiology, Ludwig-Maximilians-Universitaet, Klinikum Grosshadern, Munich, Germany.
Kuhnle
G E
GE
Ney
L
L
Sckell
A
A
Goetz
A E
AE
D000771:Anesthesia, Intravenous; D000818:Animals; D006112:Gravitation; D006439:Hemodynamics; D007530:Isoflurane / Q000494:pharmacology*; D008168:Lung / Q000098:blood supply*; D011659:Pulmonary Gas Exchange; D011817:Rabbits; D012039:Regional Blood Flow / Q000187:drug effects; D012121:Respiration, Artificial
D007530:Isoflurane