The Effect of Two-Lung Ventilation Time on PaO2 during the Sequential One-Lung Ventilation / 대한마취과학회지

BACKGROUND: During bilateral transthoracic endoscopic sympathicotomy (TES), we have noticed a tendency for hypoxemia during deflation of the second lung despite adequate reinflation of the first one. This study was designed to compare PaO2 during TES of the first side with that of TES of the second side and to investigate whether PaO2 during the sequential one-lung ventilation (OLV) was correlated with two-lung ventilation (TLV) time after reinflation of the collapsed first lung. METHODS: Forty patients were randomly allocated into two groups. After TES of the first side, OLV of the second side was immediately performed after reinflation of the collapsed first lung (group A), or after 10 minutes of TLV when switching between the operated sides (group B). Arterial blood gas samples were taken at TLV before surgery, at 2 minute intervals during OLV, and during the period of TLV when switching between the operated sides. RESULTS: In group A, the significantly decreased PaO2 was observed during TES of the second side compared with TES of the first side (P < 0.01). In group B, there was no significant difference in PaO2 except 2 minutes after OLV. PaO2 during TLV and 4 and 6 minutes after OLV of the second side TES in group A significantly decreased compared with those of group B (P < 0.05). The lowest PaO2 during OLV of the second side TES was significantly lower in group A (93.5 +/- 28.7 mmHg) than in group B (154.1+/- 48.3 mmHg). CONCLUSIONS: A significantly decreased PaO2 was observed during TES of the second side, compared with TES of the first side, and time was needed after lung collapse for its full oxygenation function to recover.

The Effect of Two-Lung Ventilation Time on PaO2 during the Sequential One-Lung Ventilation / 대한마취과학회지

BACKGROUND: During bilateral transthoracic endoscopic sympathicotomy (TES), we have noticed a tendency for hypoxemia during deflation of the second lung despite adequate reinflation of the first one. This study was designed to compare PaO2 during TES of the first side with that of TES of the second side and to investigate whether PaO2 during the sequential one-lung ventilation (OLV) was correlated with two-lung ventilation (TLV) time after reinflation of the collapsed first lung. METHODS: Forty patients were randomly allocated into two groups. After TES of the first side, OLV of the second side was immediately performed after reinflation of the collapsed first lung (group A), or after 10 minutes of TLV when switching between the operated sides (group B). Arterial blood gas samples were taken at TLV before surgery, at 2 minute intervals during OLV, and during the period of TLV when switching between the operated sides. RESULTS: In group A, the significantly decreased PaO2 was observed during TES of the second side compared with TES of the first side (P < 0.01). In group B, there was no significant difference in PaO2 except 2 minutes after OLV. PaO2 during TLV and 4 and 6 minutes after OLV of the second side TES in group A significantly decreased compared with those of group B (P < 0.05). The lowest PaO2 during OLV of the second side TES was significantly lower in group A (93.5 +/- 28.7 mmHg) than in group B (154.1+/- 48.3 mmHg). CONCLUSIONS: A significantly decreased PaO2 was observed during TES of the second side, compared with TES of the first side, and time was needed after lung collapse for its full oxygenation function to recover.

The Comparison of Pulmonary Shunt and Arterial Oxygenation between Right and Left One Lung Ventilation in Patients with Normal Lung / 대한마취과학회지

BACKGROUND: The extent of disease in the nonventilated lung is a major determinant of the amount of blood flow to the nonventilated lung during one lung anesthesia. Collapse of a normal lung may be associated with a higher nonventilated lung blood flow and pulmonary shunt. The aim of this study was to compare the difference of pulmonary shunt and arterial oxygenation between right and left one lung ventilation in patients with normal lung in the supine position. METHODS: 50 patients for bilateral thoracic sympathectomy in the supine position were selected. Patient's data (MAP, HR, PaO2, and shunt) were collected and calculated after left lung ventilation (LLV) with 50% and 100% oxygen (20 minutes interval), and after right lung ventilation (RLV) as same method. Patient,s data were compared between left and right lung ventilation. RESULTS: Under 50% oxygen, PaO2 by LLV (78.0 +/- 12.0 mmHg) was lower than PaO2 by RLV (107.7 +/- 27.9 mmHg) and pulmonary shunt by LLV (28.0 +/- 4.8%) was higher than pulmonary shunt by RLV (22.0 +/- 5.7%). Under 100% oxygen, PaO2 by LLV (143.2 +/- 28.5 mmHg) was lower than PaO2 by RLV (201.1 +/- 3.6 mmHg) and pulmonary shunt by LLV (29.7 +/- 2.5%) was higher than pulmonary shunt by RLV (25.8 +/- 2.7%). CONLUSION: Under 50% oxygen, left lung ventilation in patient with normal lung has higher risk of hypoxemia compared to right lung ventilation during one lung anesthesia in the supine position.