Anesthetic Management for Resection of a Pulmonary Arteriovenous Malformation / 대한마취과학회지

Pulmonary arteriovenous malformation (PAVM) is an uncommon congenital anomaly. As PAVM is a direct communication between branches of the pulmonary artery and vein, severe hypoxemia, paradoxical embolism, and massive hemorrhage can result. We present a 39-year-old woman with severe hypoxemia after the induction of one lung ventilation (OLV) for resection of a PAVM in her right lower lobe. We analyzed the cause of hypoxemia by an arterial blood gas analysis and estimated shunt equation. The preoperative value of an intrapulmonary shunt (Qs/Qt) was 15%. However, after the OLV, the values of Qs/Qt increased to 48% with 92.1% arterial oxygen saturation (SaO2). After the resection of PAVM, the value of Qs/Qt decreased to 36% during the OLV, and postoperative value of Qs/Qt and SaO2 were in the normal range. These findings represent that PAVM patients are prone to severe hypoxemia and an abnormally high Qs/Qt, which might be induced by the increase of pulmonary vascular resistance during OLV.

Aspiration of Blood from the Left Lung to the Right Lung and Hypoxemia during One-lung Ventilation Using Single-Lumen Endotracheal Tube / 대한마취과학회지

The leading cause of death of massive hemoptysis is the aspiration of blood into the contralateral normal lung resulting in asphyxia. The management of massive hemoptysis can be performed by the evacuation of the blood, and the protection and ventilation of the uninvolved lung from aspiration. Double-lumen endotracheal tubes provide lung isolation, the ability to ventilate one or both lungs, and suction in case of acute endobronchial hemorrhage. We report a case of blood aspiration and hypoxemia which occurred during one lung ventilation using single lumen endotracheal tube for left pneumonectomy. The patient was treated with a supplement of 100% oxygen, continual suctioning, and positive-pressure ventilation. If we had used a double-lumen endotrachal tube, it would have enabled us to separate both lungs, to clear the left lung, and to apply ventilatory support on the contralateral lung.

Comparisons between Classic Shunt and Non-Invasive Shunt in One-Lung Ventilated and Hemodiluted Dogs / 대한마취과학회지

BACKGROUND: As the clinical application of non-invasive shunt estimation to operation under one-lung ventilation has not been reported, this study was carried out to evaluate the validity and accuracy of the non-invasive shunt estimations in one-lung ventilation with hemodilution. METHODS: Following general anesthesia with enflurane 0.5 1 vol.% and 100% oxygen in ten Mongrel dogs (B.W. around 16 kg), tracheostomy and insertion of left-side endobronchial tube and one-lung ventilation were performed. Acute normovolemic hemodilution was produced by sequential hemodilution with hydroxyethyl starch. The intrapulmonary shunt (QS/QT) was calculated by the classic shunt equation, by the oxygen contents-based estimated shunt equation, and by oxygen tension-based estimations such as alveolar to arterial oxygen difference (P(A-a)O2), respiratory index (RI, P(A-a)O2/PaO2), arterial oxygen tension to alveolar oxygen ratio (PaO2/PAO2), and PaO2 to FiO2 ratio. To assess the quantitative accuracy of the estimated shunt, the data were divided arbitrarily into two groups on the basis of the mean arteriovenous oxygen content difference (C(a-v)O2) being 3.6 ml/dl or greater (group 1) and less than 3.6 ml/dl (group 2). Relationships to QS/QT were analyzed by simple linear regression. RESULTS: In 104 measurements, the correlation between QS/QT and non-invasive shunt were poor (r = 0.66 - 0.76). However, in group 1 (n = 45), the correlation between QS/QT and the estimated shunt were very good (r = 0.93) and good for P(A-a)O2 (r = 0.83), RI (r = 0.87), PaO2/PAO2 (r = - 0.84), and PaO2/FiO2 (r = - 0.85). In group 2 (n = 58), the correlation between QS/QT and non-invasive shunt were worse than in group 1. Group 2 had lower hematocrit (20.6% vs 26.7 %, P < 0.001), higher cardiac output, and lower pulmonary and systemic vascular resistance than group 1 (P < 0.05). The difference between the estimated shunt and the classic shunt in group 1 remained constant when the classic shunt was increased further. However, the difference in group 2 was enhanced by the increment of the classic shunt. CONCLUSIONS: We conclude that even if the non-invasive shunt estimation might be affected by hemoglobin and cardiac output, it is a viable method in mild hemodiluted patients with good cardiovascular reserve.

Effects of Acute Normovolemic Hemodilution on Intrapulmonary Shunt and Systemic Oxygen Delivery Balance during One Lung Ventilation in Dogs / 대한마취과학회지

BACKGROUND: The present study was done to elucidate the effects of acute normovolemic hemodilution (ANH) on intrapulmonary shunt (Qs/Qt) and systemic oxygen delivery balance during one lung ventilation (OLV). METHODS: To induce one lung ventilation, an atelectasis of the right lung was produced in anesthetized mongrel dogs. In 6 dogs with OLV, ANH was produced by sequential hemodilution with hydroxyethyl starch. ANH was divided into 3 stages (ANH0: no hemodilition, ANH1: first hemodilution, ANH2: second hemodilution). Qs/Qt was measured by using blood gas analysis. Various hemodynamic parameters, oxygen delivery, and consumption were measured or calculated indirectly. RESULTS: After hemodilution, hemoglobin levels at each stage were 9.9 +/- 1.3 g/dl (ANH0), 7.0 +/- 1.0 g/dl (ANH1), and 5.2 +/- 0.7 g/dl (ANH2). The Qs/Qt of ANH2 stage increased from 25.0 11.4% of ANH0 to 35.4 9.2% (P 0.05). Global oxygen delivery was markedly decreased by hemodilution in OLV (P < 0.05), whereas global oxygen consumption was maintained. CONCLUSIONS: We conclude that global oxygen delivery balance is preserved by ANH in this study. However, extreme ANH has a deleterious effect on pulmonary gas exchange, possibly through the attenuation of hypoxic pulmonary vasoconstriction during one-lung ventilation. On the basis of this study, increased cardiac output generated by ANH might be the cause of inhibition or blunting of hypoxic pulmonary vasoconstriction.

The Effects of Thoracic Epidural Anesthesia on Pulmonary Shunt during One Lung Anesthesia / 대한마취과학회지

BACKGROUND: Hypoxemia during one lung ventilation (OLV) for thoracotomy in patients in the lateral position remains a clinical problem. And thoracic epidural anesthesia (TEA) during one lung ventilation recently has been combined with general anesthesia in our clinical practice for thoracic surgery. Then the effects of TEA combined with general anesthesia on PaO2 remains controversial. The aim of this study to investigate whether thoracic epidural anesthesia (TEA) affect PaO2 and pulmonary shunt during one lung anesthesia. METHODS: Fifteen patients undergoing lobectomy with one lung ventilation were examined. Each group was injected normal saline (control group, n = 7) or 1% lidocaine (TEA group, n = 8) 8 ml through thoracic epidural catheter after induction. We compared pulmonary shunt fraction (Qs/Qt) after OLV 30, 60 minutes and after two lung ventilation (TLV). RESULTS: We found the significant increases of intrapulmonary shunt fraction (%) in the TEA group compared to control group at each event, OLV30, 60 and TLV. And significant increase of intrapulmonary shunt was found after one lung ventilation in the both groups. CONCLUSIONS: These results suggest that TEA may influence hypoxic pulmonary vasoconstriction (HPV) by blockade of sympathetic activity during OLV.

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.

Tracheobronchial Rupture during Double-lumen Endobronchial Tube Insertion for One-lung Ventilation: 2 cases / 대한마취과학회지

A number of complications during the use of double-lumen endobronchial tubes are reported, specifically tracheobronchial rupture, a rare but serious complication. Risk factors associated with tracheobronchial rupture include inexperienced endoscopists, intubating stylets, multiple vigorous attempts at intubation, overdistension of the tracheal or bronchial cuff with high pressure, position change with an inflated cuff, and anatomical abnormality. We report 2 cases of tracheobronchial rupture which occurred during the use of double-lumen endobronchial tubes.

Prediction of Depth of Left-sided Double Lumen Tube Insertion Using Preoperative Chest X-ray / 대한마취과학회지

INTRODUCTION: Accurate placement of double-lumen endobronchial tube (DLT) is essential for optimal gas exchange and collapse of nondependent lung during one-lung anesthesia. The goal of this study was to determine if measurement of tracheal length from the preoperative chest X-ray can be used for the prediction of adequate length of left-sided DLT insertion. METHODS: 25 patients scheduled for elective thoracotomy under one-lung anesthesia were studied. After measurement of tracheal length from preoperative chest X-ray and of length from incisor to vocal cord during intubation, the patient was intubated with left-sided DLT to the depth of predetermined length from incisor to carina. The tube position was evaluated with fiberoptic bronchocsope. RESULTS: In 22 patients (88%) the DLTs were positioned satisfactorily, and in three patients it was required to reposition DLT. CONCLUSIONS: This technique may be useful for accurate placement of DLT for the one-lung anesthesia.

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.

Effects of Inhaled Nitric Oxide on Cardiopulmonary Hemodynamics and Oxygenation during Induced Hypoxemia in Mongrel Dogs / 대한마취과학회지

INTRODUCTION: One-lung ventilation (OLV), as a model for adult respiratory distress syndrome, was performed in 8 mongrel dogs, which were made a little hypoxemic by adjusting inspired fraction of oxygen (FIO2) in order to know the effect of nitric oxide (NO) on cardiopulmonary hemodynamics and oxygenation during OLV in lateral position. METHODS: Double-lumen endobronchial tube was intubated through tracheostomy. OLV was performed in lateral position by turning to the side where Swan-Ganz catheter tip was located. FIO2 was adjusted to set SpO2 around 85~90%. After stabilization, cardiopulmonary hemodynamic variables and various oxygenation-related parameters were measured respectively at 5 steps: 1) OLV, 2) OLV and 20 PPM of NO inhalation, 3) OLV, 4) OLV and 40 PPM of NO inhalation, 5) OLV. NO (titrated in N2 tank at concentration of 800 PPM) was administered through low-pressure inlet of ventilator and diluted by inspiratory fresh gas. FIO2 setting of ventilator was slightly increased during NO administration to compensate for FIO2 decrease due to NO titration gas (N2) mixing. NO and NO2 concentration was monitored at the inspiratory limb of breathing circuit by a electrochemical analyzer. RESULTS: There were no difference about hemodynamic variables such as blood pressure (BP), pulmonary arterial pressure (PAP), heart rate (HR), central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP). Neither were different calculated hemodynamic variables such as systemic vascular resistance (SVR), pulmonary vascular resistance (PVR), pulmonary perfusion pressure (PPP), cardiac index (CI), and right ventricular stroke work index (RVSWI). PaO2/FIO2, AaDO2, and S/T were significantly different between step 3 and step 4. But other oxygenation-related parameters such as O2, O2 flux, and O2 ER extraction ratio were not different. CONCLUSIONS: NO inhalation may have a potential for relieving hypoxemia during OLV of dogs in lateral position.

Anesthetic Management of Lung Lavage in Patient with Pulmonary Alveolar Proteinosis Related to Pneumoconiosis: A case report / 대한마취과학회지

Lung lavage is an accepted modality for treatment of pulmonary alveolar proteinosis. The procedure can be accomplished by the use of double lumen endobronchial tube, with lavaging of one lung while the other is ventilated. As lung lavage is an intentional drowning, particular attention must be paid to potentially serious complications such as severe hypoxemia. We report a case of lung lavage in a patient with secondary pulmonary alveolar proteinosis performed safely by careful monitoring of oxygenation and hemodynamics.

Incidence of Malposition and it's Affecting Factors of Left-Sided Double-Lumen Endotracheal Tube / 대한마취과학회지

Backgroud: In one-lung ventilation using the left-sided double-lumen tube (LDLT), it is important to place the LDLT in correct position to maintain adequate ventilation. We investigated the frequency of and the factors affecting the LDLT malposition in endotracheal intubation. Methods: Ninety one (55 male and 36 female) patients were observed. After endotracheal intubation, using 35 and 37 Fr. sized Robertshaw type LDLT, auscultation and fiberoptic bronchoscope were performed to make sure the correct position of LDLT. The heights, weights, age, and sex were noted. The lengths and diameters of trachea, and the angles and diameters of both bronchi on chest x-ray were measured for comparison. Results: Normal in auscultation and gross malposition were 87.9% and 12.1%. Among those normal in auscultation, normal in bronchoscope, advancing and removing fine malposition were 66.2%, 18.8% and 15.0%, respectively. The angle of left bronchus is 37.71+/-4.60degrees in normal in ausculation and 37.71+/-4.60degrees in gross malposition. The length of trachea is 13.41+/-0.90 cm in normal in bronchoscope, 14.49+/-0.78 cm in advancing fine malposition and 11.86+/-0.35 cm in removing fine malposition. The patient's height is 167.27+/-7.12 cm in normal in brochoscope, 172.45+/-6.67 cm in advancing fine malposition and 163.12+/-6.54 cm in removing fine malposition. Conclusions: The angle of left bronchus is a factor affecting gross malposition. And the length of trachea and the patient's height are factors affecting fine malposition. Thus it is necessary to obtain in advance information on patient's height, length of trachea and angle of left bronchus on chest x-ray, to reduce the occurrence of the LDLT malposition.

The Degree of Bronchial Mucosal Damages Related to the Bronchial Blocker Cuff Pressure of Univent(R) Tube / 대한마취과학회지

Background: Univent(R) tube was designed to overcome the disadvantages of double lumen endotracheal tube for one lung anesthesia. But overinflation of the blocker cuff of an endobronchial tube can cause pressure damage to the bronchus. The purpose of this study was to evaluate whether the blocker cuff pressure and the duration of ballooning using the Univent(R) tube is correlated with the degree of bronchial mucosal damage (BMD). Methods: A total of 13 men and 7 women intubated with the Univent(R) tube were enrolled for the study. The BMD were evaluated by direct visualization using fiberoptic bronchoscopy prior to intubation and following extubation and the degree of the BMD were scored from 0 to 4 as follows; 0: normal, 1: erythema, 2: swelling, 3: hemorrhage, 4: mucosal wall tearing. Results: No change in bronchial mucosa (score 0) were observed in 11 patients (55%), erythema (score 1) in 5 patients (25%), swelling (score 2) in 3 patients (15%), hemorrhage (score 3) in 1 patient (5%) and mucosal wall tearing (score 4) is none in 20 patients. The bronchial blocker cuff pressure required to "just sealing" the bronchus was 178.1+/-37.4 mmHg with corresponding cuff volume of 6.7+/-1.0 cc. The duration of ballooning was 115.5+/-26.4 min. The correlation coefficient between the blocker cuff pressure and duration of ballooning to the degree of bronchial mucosal damage were 0.125 and 0.137, respectively, which was not statistically significant. Conclusions: The bronchial blocker of Univent(R) tube doesn't cause any severe BMD and the degree of BMD are correlated with neither the bronchial blocker cuff pressure nor duration of ballooning of Univent(R) tube.

Effect of High Frequency Jet Ventilation alone or with Positive End Expiratory Pressure on the Arterial Oxygenation during One Lung Ventilation / 대한마취과학회지

BACKGROUND: Hypoxemia during one lung ventilation (OLV) may occur in spite of high inspired oxygen concentration. The purpose of this study was to evaluate the effect of highfrequency jet ventilation (HFJV) alone to the non-ventilated lung or in combination with 5 cmH2O of positive end expiratory pressure (PEEP) to the ventilated lung on arterial oxygenation (PaO2) during OLV for thoracic surgery. METHODS: After endotracheal intubation with double lumen tube, arterial blood gases were measured 20 minutes after stabilization had occurred following onset of OLV, HFJV, and HFJV with 5 cmH2O of PEEP. RESULT: The mean PaO2 during OLV was 257.5+/-81.7 mmHg, and application of HFJV alone or with PEEP resulted in a significant increase in PaO2 to 356.6+/-79.1 mmHg and 354.9+/-66.6 mmHg, respectively (p<0.001). Alveolar-arterial oxygen differences were significantly decreased as compared to OLV. CONCLUSION: Both HFJV alone or in combination with 5cmH2O of PEEP are effective to improve oxygenation during OLV.

The Effects of CO2 Insufflation on Jugular Bulb Venous Blood Oxygen Saturation during Thoracoscopy / 대한마취과학회지

BACKGROUNDS: Carbon Dioxide (CO2) insufflation during thoracoscopy may result in adverse hemodynamic consequences such as increase in central venous pressure, decrease in cardiac output and increase in arterial carbon dioxide pressure. But the cerebral effects of CO2 insufflation during thoracoscopy are not known yet. To evaluate the cerebral effect of CO2 insufflation during thoracoscopy, jugular bulb venous blood oxygen saturation and pressure were measured. METHODS: Nine patients were underwent thoracic surgery by thoracoscopy and one lung ventilation. After operation, CO2 was insufflated and hemodynamic parameters, arterial blood pressure, heart rate, central venous pressure, jugular bulb pressure, arterial blood gases and jugular bulb venous blood gases were measured at intrathoracic pressure 5 mmHg, 10 mmHg and 15 mmHg respectively. RESULTS: Central venous pressure was increased with insufflation of CO2 of 10 mmHg and 15 mmHg. Jugular bulb pressure was increased with insufflationof of CO2 of 5mmHg, 10 mmHg and 15 mmHg. Arterial PCO2, jugular bulb venous PO2 and jugular bulb venous blood oxygen saturation were increased with insufflation of CO2 of 5 mmHg, 10 mmHg and 15 mmHg. CONCLUSION: CO2 insufflation pressure of 5 mmHg or greater resulted in significant increase in jugular bulb venous blood oxygen saturation and pressure.

The Comparison of the Effect of Enflurane and Propofol on Arterial Oxygenation during One-Lung Ventilation / 대한마취과학회지

BACKGROUND: Controversy exists as to whether or not inhalation anesthetics and intravenous anesthetics impair arterial oxygenation (PaO2) during one lung ventilation (OLV). Accordingly, we examined the effect of enflurane and propofol on PaO2 and pulmonary vascular resistance (PVR) during OLV. METHODS: Forty patients, who had prolonged periods of OLV anesthesia with minimal trauma to the nonventilated lung were studied in a cross over design. Patients were randomized to four groups; Group 1 received 1 MAC of enflurane and oxygen from induction until the first 20 min after complete lung collapse, then were switched to propofol 100 g/kg/min (P100). In group 2, the order of the anesthetics was reversed. Group 3, Group 4 received the same order of the anesthetics as Group 1, Group 2, respectively but received propofol 200 g/kg/min (P200). RESULTS: During OLV, the PaO2 values were lower than those with two lung ventilation (TLV), there were no significant differences among each groups and between propofol and enflurane in PaO2, but in the selected patients (n=10, PaO2<120 mmHg during OLV), PaO2 in propofol group was higher than that of enflurane group (p<0.05). Conversion from TLV to OLV caused a significant increase in PVR, but there were no difference in PVR between propofol and enflurane group. CONCLUSIONS: These results suggest that the usual clinical dose of propofol affords no advantage over 1 MAC of enflurane anesthesia except low PaO2 patients during OLV. Propofol might be of value in risk patients of hypoxemia during thoracic surgery when OLV is planned.

Clinical Evaluation of Univent Tube for One Lung Ventilation / 대한마취과학회지

BACKGROUND: Univent tube(endotracheal tube with a movable blocker), introduced by Inoue et al in 1982, has properties to overcome the disadvantages of double lumen endotracheal tube for one lung anesthesia. This study was performed to evaluate the effectiveness of Univent tube for one lung ventilation. METHODS: Univent tube was inserted to the patients for open thoracic surgery and positioned to the side of bronchus under the guidance of fiberoptic bronchoscope that was scheduled to lung collapse. One lung anesthesia was performed with the inflation of cuff of blocker. Each case was anaylzed with respect to ease or difficulty of positioning of blocker, tube displacement, efficacy of lung collapse and adequacy of single lung ventilation. RESULTS: In the 69 patients out of 80 patients, adequate positioning was performed by first trial. In the two patients, insertion of bronchial blocker was failed that resulted in replacement with a double lumen tube. Observed disadvantages were delayed deflation(10 patients) of affected lung and displacement of bronchial cuff into the main tracheal lumen during position change or surgical manipulation(7 patients). CONCLUSIONS: Univent tube is useful for one lung anesthesia but there are several distinct limitaitons in the safe use.

Bronchial Cuff Volume of Univent Tube for One Lung Ventilation / 대한마취과학회지

BACKGROUND: The univent tube is an endotracheal tube with a movable bronchial blocker for one lung ventilation. The purpose of this study was to measure the appropriate cuff volume sealing the mainstem bronchus by three different techniques. METHODS: This study was performed in 60 adult patients undergoing thoracotomy. 1) The negative pressure was applied to the end of blocker causing loss of volume in the breathing system. The blocker cuff volume was measured at the point of the bag ceased to deflate. 2) The blocker cuff volume was measured when breathing sound is not heard on blocked lung. 3) Then the capnometer was applied to the blocker and the cuff volume was measured at the point of the CO2 wave ceased abruptly. The bronchial blocker volumes from these three methods were compared with the volume which was measured when the lung was completely collapsed in operation field. RESULTS: Left bronchial sealing volume was 2.7+/-?0.8 ml with negative pressure technique, 3.5+/-0.8 ml with auscultation, 3.2?1.2 ml with CO2 technique and 3.0+/-0.7 ml with complete lung collapse at operation field. Right bronchial sealing volume ranged 3.5+/-0.9 ml with negative pressure technique, 4.6+/-1.0 ml with auscultation, 3.9+/-0.6 ml with CO2 technique and 4.2+/-0.9 ml with complete lung collapse at operation field. CONCLUSIONS: We concluded that right bronchial blocker volume was 4.2+/-0.9 ml and left bronchial blocker volume was 3.0+/-0.7 ml. The right bronchial blocker volume was larger than the left.

Is There Any Difference in Arterial Oxygenation between the Right and Left Thoracic Surgery under the Different One Lung Ventilation Mode? / 대한마취과학회지

BACKGROUND: Use of one lung anesthesia for thoracic surgery may compromize PaO2. The aim of this study was to compare the shunt and oxygenation effects of the application of CPAP and CPAP/PEEP between right and left thoracic surgery under one lung anesthesia. METHODS: 10 patients for right thoracic surgery were selected as group 1, and 10 patients for left thoracic surgery were selected as group 2. Measurements in each group, were made during each of the following stage. First 30 minutes, One lung anesthesia alone with 50% oxygen (control value), next 30 minutes, CPAP 10 cmH2O to upper lung with 50% oxygen (CPAP), and then CPAP 10 cmH2O to upper lung and PEEP 10 cmH2O to down lung with 50% oxygen for 30 minutes (CPAP/PEEP). RESULTS: PaO2 in CPAP and CPAP/PEEP were significantly increased as compare to control value at both group (P<0.05). Shunt percentage in CPAP and CPAP/PEEP were significantly decreased as compare to control value at both group (P<0.05). But, no statistically significant differences were observed between right and left thoracic surgery group in the PaO2 and shunt percentage. CONCLUSIONS: We confirmed that CPAP and CPAP/PEEP during one lung ventilation is thought to be effective method in preventing hypoxemia, but no differences were observed between right and left thoracic surgery group.