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Transesophageal Echocardiography During Lung Transplantation
Transesophageal Echocardiography During Lung Transplantation E. Serra, P. Feltracco, S. Barbieri, A. Forti, and C. Ori ABSTRACT Transesophageal echocardiography (TEE) is a semiinvasive monitoring technique increasingly used in cardiac surgery and in major noncardiac surgery for patients with known or supposed cardiac or coronary problems. During lung transplantation (LTx), the close interrelation between heart and lung function makes TEE an invaluable tool for instantly monitoring the physiopathological situation in the subsequent steps of the intervention. In patients scheduled for LTx, induction of anesthesia could be a dangerous moment with the possibility of cardiogenic shock if pulmonary hypertension (PH) exists; pneumatic tamponade is also possible in patients with emphysema caused by ␣1-antitrypsin deficiency, with subsequent cardiac insufficiency. One-lung ventilation is a critical phase during LTx; hypoxemia resulting from ventilation of a diseased dependent lung could impair heart oxygenation, particularly if tachycardia is present. Clamping of the pulmonary artery before pneumonectomy could exacerbate cardiac afterload, especially in patients with previous PH. High transmural pressure, linked with low systemic pressure, makes right ventricle (RV) perfusion pressure inadequate. Hypoxemia and PH are the most frequent causes of intraoperative RV decompensation. In this special setting, TEE is irreplaceable in informing the anesthesiologist about the correct time for extracorporeal oxygenation. Lung reperfusion brings with it the possibility of coronary gaseous embolism, easily detected with TEE. After LTx, TEE can be used to detect strictures, thrombi, or permeability of pulmonary venous anastomoses. To summarize, intraoperative TEE during LTx contributes to the immediate recognition of critical events and allows for rapid therapeutic interventions.
T
RANSESOPHAGEAL echocardiography (TEE) is a semiinvasive monitoring technique that has been gaining increased acceptance among anesthesiologists for intraoperative evaluation of heart anatomy and function.1 Obviously, cardiac surgery is the main application of TEE, and nearly every cardiac anesthesiologist is skilled enough to perform TEE and interpret TEE findings. Major noncardiac surgery for patients with known or suspected cardiac or coronary diseases is an interesting area of TEE application.2,3 Lung transplantation (LTx), single and bilateral sequential, is a complex and challenging anesthesiological procedure because of rapidly developing and, at times, dramatic hemodynamic and respiratory deteriorations. During LTx, TEE is usually used in combination with other cardiac or hemodynamic monitoring systems, eg, invasive systemic artery pressure measurement, pulmonary artery (PA) catheter, and PiCCO system (Pulsion Medical System, Munich, Germany).4,5
Induction of anesthesia in lung transplant recipients is often a dangerous moment because of alterations of respiratory mechanics, loss of muscular tone, surgical positioning, and mechanical ventilation with impaired gas exchange, namely, reduced arterial blood oxygenation and carbon dioxide retention. At this time, cardiogenic shock is also possible, mainly in hypovolemic patients with pulmonary hypertension (PH).6 In ␣1antitrypsin deficiency, patients with severe emphysema can experience pneumatic tamponade, with subsequent cardiac failure, presenting a very difficult clinical picture to understand and to treat. In these settings, TEE can From the Department of Pharmacology and Anesthesia, University Hospital of Padova, Padova, Italy. Address reprint requests to Eugenio Serra, MD, Department of Pharmacology and Anesthesia, University Hospital of Padova, Via Giustiniani, 2 35128 Padova, Italy. E-mail: eugenioserra@ libero.it
© 2007 by Elsevier Inc. All rights reserved. 360 Park Avenue South, New York, NY 10010-1710
0041-1345/07/$–see front matter doi:10.1016/j.transproceed.2007.05.004
Transplantation Proceedings, 39, 1981–1982 (2007)
1981
1982
easily detect the onset of cardiovascular abnormalities, allowing for rapid and effective therapy.7 PA clamping, performed before pneumonectomy and graft implantation, is one of the most hazardous intraoperative periods during LTx. Almost all patients accepted for LTx have some degree of PH, either idiopathic or as a result of pulmonary disease. In a patient with PH, diversion of cardiac output and pulmonary blood flow to one lung can result in both right ventricle (RV) and tricuspid valve dysfunction. The complex geometry of the RV prevents an easy functional assessment using TEE and requires a skilled observer. However, some echocardiographic methods, ie, planimetry and plane systolic excursion, Doppler echocardiography, RV ejection fraction, septal curvature, and real-time visual assessment, allow a qualitative but relatively precise evaluation of RV function.7,8 PA clamping can induce an acute RV dilation, sustained by a sudden pulmonary pressure elevation, with tricuspid regurgitation and paradoxical interventricular septal shift. The septal shift occurs in late diastole with RV volume overload and at end-systole and early diastole with RV pressure overload. Septal shifting hampers left ventricular diastolic filling with low cardiac output and systemic low blood pressure. The high right atrial pressure, linked to trans-tricuspid systolic regurgitation, in combination with atrial septal defect or a patent foramen ovale, may induce right-to-left intracardiac shunt and intraoperative arterial hypoxemia. Atrial septal defects previously not recognized, with consistent abnormal shunt flow across the defect, can be detected by pulsed-wave Doppler, color-flow imaging, or contrast (saline agitated to produce microbubbles) TEE. Systemic hypotension and hypoxemia impair myocardial perfusion and oxygenation; in particular, a reduced mean aortic-to-right ventricle pressure gradient represents the main mechanism of worsening RV contractility. Both direct and indirect signs of these negative interactions can be detected and qualitatively measured using TEE. In this circumstance, real-time visual monitoring is the best tool to determine appropriate treatment.7,9 TEE may be extremely useful in LTx in determining the need for cardiopulmonary bypass, based on changes in the maximum acceleration of blood in the PA, along with the classic signs of imminent impending RV decompensation. Graft reperfusion could be the source of trouble in transplant recipients. Gaseous left heart embolism (bubbles from the pulmonary veins of an “irregularly flushed” allograft), left ventricle sectorial stunning (induced by reperfusion phenomena and/or coronary air embolism), and strictures of, or thrombi on, pulmonary-atrial anastomoses are easily detectable with TEE.10 Pulmonary vein diameter, color-flow pattern, and pulsed-wave Doppler profile measurements are useful for this purpose.11–13 In the post-anesthesia period, hypoxemia is a major concern after LTx; among the various causes are the obstruction of normal pulmonary blood flow and intracardiac shunting. PA anastomoses are often well visualized and the transanastomotic pressure gradient measured with
SERRA, FELTRACCO, BARBIERI ET AL
TEE (color-flow, pulsed-wave Doppler). In the same way, pulmonary-atrial venous anastomoses are recognized and blood flow pattern and velocity are measured. TEE confirmation of absence of cardiac tamponade and visualization of myocardial wall motion and preload are extremely important in guiding therapeutic strategies in cases of postoperative circulatory instability.14,15 To summarize, intraoperative TEE during LTx contributes to the immediate recognition of critical events and allows for rapid therapeutic interventions. Although TEE examination requires a relatively prolonged learning process, improved confidence with the technique has an invaluable positive impact on both anesthesiological and surgical management of complicated lung transplant recipients. REFERENCES 1. A report by American Society of Anesthesiologists and the Society of Cardiovascular Anesthesiologists Task Force on Transesophageal Echocardiography: Practical guidelines for perioperative transesophageal echocardiography. Anesthesiology 84:986, 1996 2. Theodoraki K, Tsiapras D, Tsourelis L, et al: Inhaled iloprost in eight heart transplant recipients presenting with post-bypass acute right ventricular dysfunction. Acta Anesthesiol Scand 50: 1213, 2006 3. Guarracino F, Cariello C, Danella A, et al: Right ventricular failure: physiology and assessment. Minerva Anesthesiol 71:307, 2005 4. Meyers BF, Patterson GA: Lung transplantation: current status and future prospects. World J Surg 23:1156, 1999 5. Miranda A, Zink R, McSweeney M: Anesthesia for lung transplantation. Semin Cardiothorac Vasc Anesth 9:205, 2005 6. Höhn L, Schweizer A, Morel D, et al: Circulatory failure after anesthesia induction in a patient with severe primary pulmonary hypertension. Case reports. Anesthesiology 91:1943, 1999 7. Suriani RJ: Transesophageal echocardiography during organ transplantation. J Cardiothorac Vasc Anesth 12:686, 1998 8. Katz WE, Gasior TA, Quinlan JJ, et al: Immediate effects of lung transplantation on right ventricular morphology and function in patients with variable degrees of pulmonary hypertension. J Am Coll Cardiol 27:384, 1996 9. Singh H, Bosard RF: Perioperative anaesthetic considerations for patients undergoing lung transplantation. Can J Anaesth 44: 284, 1997 10. Xie GY, Lin CS, Preston HM, et al: Assessment of left ventricular diastolic function after single lung transplantation in patients with severe pulmonary hypertension. Chest 114:477, 1998 11. Miyaii K, Matsubara H, Nakamura K, et al: Equivalence of flow velocities through bilateral pulmonary vein anastomoses in bilateral living-donor lobar lung transplantation. J Heart Lung Transplant 24:860, 2005 12. Huang Y-C, Cheng Y-J, Lin Y-H, et al: Graft failure caused by pulmonary venous obstruction diagnosed by intraoperative transesophageal echocardiography during lung transplantation. Anesth Analg 91:558, 2000 13. Michel-Cherqui M, Brusset A, Liu N, et al: Intraoperative transesophageal echocardiographic assessment of vascular anastomoses in lung transplantation. A report on 18 cases. Chest 111: 1229, 1999 14. Murtha W, Guenther C: Dynamic left ventricular outflow tract obstruction complicating bilateral lung transplantation. Anaesth Analg 94:558, 2002 15. Sakamaki Y, Minami M, Ohta M, et al: Pulmonary artery dissection complicating lung transplantation for primary pulmonary hypertension. Ann Thorac Surg 81:360, 2006
T
RANSESOPHAGEAL echocardiography (TEE) is a semiinvasive monitoring technique that has been gaining increased acceptance among anesthesiologists for intraoperative evaluation of heart anatomy and function.1 Obviously, cardiac surgery is the main application of TEE, and nearly every cardiac anesthesiologist is skilled enough to perform TEE and interpret TEE findings. Major noncardiac surgery for patients with known or suspected cardiac or coronary diseases is an interesting area of TEE application.2,3 Lung transplantation (LTx), single and bilateral sequential, is a complex and challenging anesthesiological procedure because of rapidly developing and, at times, dramatic hemodynamic and respiratory deteriorations. During LTx, TEE is usually used in combination with other cardiac or hemodynamic monitoring systems, eg, invasive systemic artery pressure measurement, pulmonary artery (PA) catheter, and PiCCO system (Pulsion Medical System, Munich, Germany).4,5
Induction of anesthesia in lung transplant recipients is often a dangerous moment because of alterations of respiratory mechanics, loss of muscular tone, surgical positioning, and mechanical ventilation with impaired gas exchange, namely, reduced arterial blood oxygenation and carbon dioxide retention. At this time, cardiogenic shock is also possible, mainly in hypovolemic patients with pulmonary hypertension (PH).6 In ␣1antitrypsin deficiency, patients with severe emphysema can experience pneumatic tamponade, with subsequent cardiac failure, presenting a very difficult clinical picture to understand and to treat. In these settings, TEE can From the Department of Pharmacology and Anesthesia, University Hospital of Padova, Padova, Italy. Address reprint requests to Eugenio Serra, MD, Department of Pharmacology and Anesthesia, University Hospital of Padova, Via Giustiniani, 2 35128 Padova, Italy. E-mail: eugenioserra@ libero.it
© 2007 by Elsevier Inc. All rights reserved. 360 Park Avenue South, New York, NY 10010-1710
0041-1345/07/$–see front matter doi:10.1016/j.transproceed.2007.05.004
Transplantation Proceedings, 39, 1981–1982 (2007)
1981
1982
easily detect the onset of cardiovascular abnormalities, allowing for rapid and effective therapy.7 PA clamping, performed before pneumonectomy and graft implantation, is one of the most hazardous intraoperative periods during LTx. Almost all patients accepted for LTx have some degree of PH, either idiopathic or as a result of pulmonary disease. In a patient with PH, diversion of cardiac output and pulmonary blood flow to one lung can result in both right ventricle (RV) and tricuspid valve dysfunction. The complex geometry of the RV prevents an easy functional assessment using TEE and requires a skilled observer. However, some echocardiographic methods, ie, planimetry and plane systolic excursion, Doppler echocardiography, RV ejection fraction, septal curvature, and real-time visual assessment, allow a qualitative but relatively precise evaluation of RV function.7,8 PA clamping can induce an acute RV dilation, sustained by a sudden pulmonary pressure elevation, with tricuspid regurgitation and paradoxical interventricular septal shift. The septal shift occurs in late diastole with RV volume overload and at end-systole and early diastole with RV pressure overload. Septal shifting hampers left ventricular diastolic filling with low cardiac output and systemic low blood pressure. The high right atrial pressure, linked to trans-tricuspid systolic regurgitation, in combination with atrial septal defect or a patent foramen ovale, may induce right-to-left intracardiac shunt and intraoperative arterial hypoxemia. Atrial septal defects previously not recognized, with consistent abnormal shunt flow across the defect, can be detected by pulsed-wave Doppler, color-flow imaging, or contrast (saline agitated to produce microbubbles) TEE. Systemic hypotension and hypoxemia impair myocardial perfusion and oxygenation; in particular, a reduced mean aortic-to-right ventricle pressure gradient represents the main mechanism of worsening RV contractility. Both direct and indirect signs of these negative interactions can be detected and qualitatively measured using TEE. In this circumstance, real-time visual monitoring is the best tool to determine appropriate treatment.7,9 TEE may be extremely useful in LTx in determining the need for cardiopulmonary bypass, based on changes in the maximum acceleration of blood in the PA, along with the classic signs of imminent impending RV decompensation. Graft reperfusion could be the source of trouble in transplant recipients. Gaseous left heart embolism (bubbles from the pulmonary veins of an “irregularly flushed” allograft), left ventricle sectorial stunning (induced by reperfusion phenomena and/or coronary air embolism), and strictures of, or thrombi on, pulmonary-atrial anastomoses are easily detectable with TEE.10 Pulmonary vein diameter, color-flow pattern, and pulsed-wave Doppler profile measurements are useful for this purpose.11–13 In the post-anesthesia period, hypoxemia is a major concern after LTx; among the various causes are the obstruction of normal pulmonary blood flow and intracardiac shunting. PA anastomoses are often well visualized and the transanastomotic pressure gradient measured with
SERRA, FELTRACCO, BARBIERI ET AL
TEE (color-flow, pulsed-wave Doppler). In the same way, pulmonary-atrial venous anastomoses are recognized and blood flow pattern and velocity are measured. TEE confirmation of absence of cardiac tamponade and visualization of myocardial wall motion and preload are extremely important in guiding therapeutic strategies in cases of postoperative circulatory instability.14,15 To summarize, intraoperative TEE during LTx contributes to the immediate recognition of critical events and allows for rapid therapeutic interventions. Although TEE examination requires a relatively prolonged learning process, improved confidence with the technique has an invaluable positive impact on both anesthesiological and surgical management of complicated lung transplant recipients. REFERENCES 1. A report by American Society of Anesthesiologists and the Society of Cardiovascular Anesthesiologists Task Force on Transesophageal Echocardiography: Practical guidelines for perioperative transesophageal echocardiography. Anesthesiology 84:986, 1996 2. Theodoraki K, Tsiapras D, Tsourelis L, et al: Inhaled iloprost in eight heart transplant recipients presenting with post-bypass acute right ventricular dysfunction. Acta Anesthesiol Scand 50: 1213, 2006 3. Guarracino F, Cariello C, Danella A, et al: Right ventricular failure: physiology and assessment. Minerva Anesthesiol 71:307, 2005 4. Meyers BF, Patterson GA: Lung transplantation: current status and future prospects. World J Surg 23:1156, 1999 5. Miranda A, Zink R, McSweeney M: Anesthesia for lung transplantation. Semin Cardiothorac Vasc Anesth 9:205, 2005 6. Höhn L, Schweizer A, Morel D, et al: Circulatory failure after anesthesia induction in a patient with severe primary pulmonary hypertension. Case reports. Anesthesiology 91:1943, 1999 7. Suriani RJ: Transesophageal echocardiography during organ transplantation. J Cardiothorac Vasc Anesth 12:686, 1998 8. Katz WE, Gasior TA, Quinlan JJ, et al: Immediate effects of lung transplantation on right ventricular morphology and function in patients with variable degrees of pulmonary hypertension. J Am Coll Cardiol 27:384, 1996 9. Singh H, Bosard RF: Perioperative anaesthetic considerations for patients undergoing lung transplantation. Can J Anaesth 44: 284, 1997 10. Xie GY, Lin CS, Preston HM, et al: Assessment of left ventricular diastolic function after single lung transplantation in patients with severe pulmonary hypertension. Chest 114:477, 1998 11. Miyaii K, Matsubara H, Nakamura K, et al: Equivalence of flow velocities through bilateral pulmonary vein anastomoses in bilateral living-donor lobar lung transplantation. J Heart Lung Transplant 24:860, 2005 12. Huang Y-C, Cheng Y-J, Lin Y-H, et al: Graft failure caused by pulmonary venous obstruction diagnosed by intraoperative transesophageal echocardiography during lung transplantation. Anesth Analg 91:558, 2000 13. Michel-Cherqui M, Brusset A, Liu N, et al: Intraoperative transesophageal echocardiographic assessment of vascular anastomoses in lung transplantation. A report on 18 cases. Chest 111: 1229, 1999 14. Murtha W, Guenther C: Dynamic left ventricular outflow tract obstruction complicating bilateral lung transplantation. Anaesth Analg 94:558, 2002 15. Sakamaki Y, Minami M, Ohta M, et al: Pulmonary artery dissection complicating lung transplantation for primary pulmonary hypertension. Ann Thorac Surg 81:360, 2006