Arterial oxygenation during one lung ventilation

Abstract

Purpose: To compare the effects of isoflurane and sevoflurane on arterial oxygenation and middle cerebral artery blood flow velocity during one lung ventilation. Methods: This was a randomized, crossover study in 20 patients undergoing thoracotomy for oesophageal cancer and scheduled for long term one lung ventilation (OLV). They were randomized to one of two groups: group A, firstly isoflurane was administered followed by sevoflurane, and then isoflurane was resumed; group 13, the order of the administration was reversed, Arterial blood gas samples were drawn at the start of OLV, 30 and 60 min after the initiation of OLV and the end of OLV (the change of volatile anesthetics was done 30 and 60 min after the start of OLV). Middle cerebral artery (MCA) was monitored continuously with the probe positioned over the temporal bone window. This probe transmitted 2 MHZ wave Doppler signals. Time-averaged MCA blood flow velocity was calculated from the signals. Results: The PaO2 values decreased 30 min after the start of OLV (364.4 +_ 33.4 mmHg vs 179.0 +_ 19.5. and 338,7 _+ 24.8 mmHg vs 139.7 ___ 19.9 in groups A and 13 respectively), but there was no difference between the groups, Blood flow velocity of MCA did not change after the start of OLV (53. I ___ 3.2, 55.9 _+ 3.0, 56.4 ___ 2,4, and 54. I _+_ 1.9 vs 50.8 _+ 2, I, 50.7 +--2.4, 53.7 • 1.5, 50.8 -+ 2.2 cm'sec-' in groups A and 13 respectively): there was no difference between the groups. (P < 0.05). Conclusion: In clinical practice, the selection of either isoflurane and sevoflurane for OLV was of no difference in terms of the artenal blood oxygenation. With both agents MCA blood flow velocity was maintained dudng OLV.

Unstable endobronchial intubation in a cat undergoing tracheal laceration repair

“…The principle cardiopulmonary effects of singlelung ventilation in human beings and dogs are decreased PaO 2 and increased shunt fraction (Lü bbe et al 1991;Shimizu et al 1997;Cantwell et al 2000). In this case, arterial blood gas tensions were not measured and changes in arterial oxygenation may have gone unrecognized, despite the use of pulse oximetry.…”

“…The principle cardiopulmonary effects of single‐lung ventilation in human beings and dogs are decreased PaO 2 and increased shunt fraction (Lübbe et al. 1991; Shimizu et al 1997; Cantwell et al. 2000).…”

Accidental Entrapment of an Endo‐Bronchial Blocker Tip by a Surgical Stapler During Selective Ventilation for Lung Lobectomy in a Dog

“…Another disadvantage of one-lung ventilation is hypoxemia caused by ventilation perfusion mismatch as occurred in our dog. 1,4,5,9,10 Total intravenous anesthesia (TIVA) was used in this dog because it limits hypoxemia by better preserving hypoxic pulmonary vasoconstriction [11][12][13] and minimizes hypotension. Despite TIVA, slight hypoxemia occurred in this dog.…”

New Developments in Thoracic Anesthesia

“…1,37 They also cause vasodilatation of the vessels in the ventilated lung, which augments the blood flow redistribution due to hypoxic pulmonary vasoconstriction (HPV) in the nonventilated lung. Increased oxygen concentrations serve to protect against hypoxemia during the procedure and provide a greater margin of safety.…”