Preoperative respiratory assessment should include pulmonary function tests, ventilation/perfusion (V/Q) scans, and an arterial blood gas. The patient's ability to tolerate one-lung ventilation can be determined by V/Q scan, and if both lungs are being transplanted the lung with less perfusion should be transplanted first.
Cardiac function should be assessed with particular attention paid to evaluation of right ventricular (RV) function. Elevated pulmonary arterial pressures can precipitate RV failure, and may greatly influence the decision to attempt transplantation with or without CPB.
The newly transplanted lung should be ventilated with as low a FiO2 as possible, ideally room air, to minimize damage by oxygen free radicals. Barotrauma to the new lung can be avoided by keeping inspiratory pressures less than 25 cm H2O and PEEP less than 10 cm H2O.
Hemodynamic instability or refractory hypoxemia may deem cardiopulmonary bypass necessary and typically occurs at one of three critical phases of the operation: (a) after pulmonary artery clamping during the first transplant; (b) after perfusing the first allograft but before starting the second lung; and, (c) after pulmonary artery clamping during the second transplant.
The patient is a 45-year-old man who is listed for bilateral sequential lung transplantation due to idiopathic pulmonary fibrosis. He has undergone pulmonary rehabilitation and now continuously uses oxygen at the rate of 4 L/min. His PA pressures are 68/25. Recently his respiratory symptoms have worsened significantly and he has thus been moved to the active transplant list.
He has mild esophageal reflux disease and is otherwise well.
He takes famotidine and albuterol by mouth and is on an epoprostenol (Flolan) infusion.
Vital signs: 105/60, HR 95, SpO2 on 4 L/min oxygen 91%.
Laboratory values are normal.
Providing anesthesia for lung transplantation (LT) is considered by many to be the coup de maître of cardiothoracic anesthesia. Some say it involves the most complex manipulation of cardiothoracic physiology, particularly when cardiopulmonary bypass (CPB) is not used. Many anesthetic considerations for LT are in fact similar to those for other thoracic and cardiovascular procedures; however, this chapter highlights the unique clinical elements involved in perioperative management of LT recipients and the implications for their future anesthetic care. Because LT is performed infrequently in clinical practice, typically with little opportunity for preoperative preparation and consultation, a thorough understanding of end-stage lung disease pathophysiology and its specific pharmacological and technical implications is required to minimize associated major morbidity and mortality.
Indications for LT include 4 primary diagnostic groupings of end-stage pulmonary disease: (1) obstructive lung disease (chronic obstructive pulmonary disease [COPD], with or without alpha-1-antitrypsin deficiency, due to chronic bronchitis and/or emphysema, and bronchiectasis); (2) restrictive lung disease (idiopathic pulmonary fibrosis [IPF], sarcoidosis, obliterative bronchiolitis); (3) cystic fibrosis or immunodeficiency disorders (hypogammaglobulinemia); and (4) pulmonary vascular disease (idiopathic pulmonary arterial hypertension, Eisenmenger syndrome). In 2007, patients with IPF comprised the single ...