Anaesthesia for lung volume reduction surgery

Lung volume reduction surgery is a surgical treatment for severe emphysema that is increasing in popularity. The aim is to reverse the hyperexpansion of the lungs that leads to expiratory airflow limitation, compromises the diaphragm and chest wall mechanics, and tamponades the right ventricle. Optimal patient selection has not yet been established, but it has become clear that those patients with the most severe disease have an unacceptably high surgical mortality. The anaesthetic management of patients undergoing lung volume reduction surgery requires a good understanding of both the pathophysiology of the disease and the surgical procedure. It is important for the anaesthetist and the surgeon to work closely, supported by a large multidisciplinary team. Excellent analgesia is essential to a successful outcome; whether this is best provided by thoracic epidural is as yet unclear.     

Anaesthesia for lung volume reduction surgery

To date, only a few published studies have been concerned with the anaesthesiological aspects of lung volume reduction surgery. This review summarizes the different anaesthetic concepts and offers a general strategy to meet specific requirements. Limitation of peak inspiratory pressure, tolerance of hypercapnia and avoidance of hypoxia during one-lung ventilation, and the immediate postoperative tracheal extubation of these patients, are considered to be crucial. However, many aspects of the procedure and of anaesthesiological management remain to be elucidated.     

Anesthesia for lung volume reduction surgery

Background: Lung volume reduction surgery (LVRS) has become a novel palliative procedure for a subgroup of patients with advanced non-bullous emphysema. METHODS: Seventy-six patients with severe emphysema were evaluated: ten patients were considered for lung transplantation and only 24 underwent LVRS. In all patients an epidural catheter was inserted between the T5-T9 space. During one lung ventilation (OLV), ventilatory setting was adjusted to avoid air trapping and/or dynamic hyperinflation and high frequency jet ventilation was used when PaO2/ FiO2 was lower than 60 mmHg in 5 patients. Permissive hypercapnia (PaCO2=53 mmHg) was allowed to avoid hyperinflation and reach hemodynamic stability. RESULTS: During OLV PaO2/FiO2 was 148+/-80 mmHg, PaCO2 53+/-11 mmHg, mPA 27+/-2 mmHg and Qsp/Qt was 38+/-6%. Although the high risk patients, there were no complications due to hypercapnia during surgery. Twenty-three patients were extubated successfully at the end of the surgery (PaO2/FiO2 179+/-34 mmHg and PaCO2 59+/-11 mmHg) and only one patient was not extubated because of air leakage and died for postoperative respiratory failure after 20 days. Another patient died because of sepsis after 15 days. Numeric Ordinal Verbal Scale (by Keele modified) was used for postoperative pain degree at 0, 12th and 24th hours. No patients had pain>2. CONCLUSIONS: In conclusion, a careful anesthesia technique with an accurate intraop monitoring associated with thoracic epidural analgesia even in Video Assisted Thoracic Surgery is suggested in LVRS patients; 12 months postoperative data confirm the validity of the procedure (FEV1 24 AE 36%, FVC 53 AE 70%, RV 265 AE 199% and 6MWT 213 AE 330 m).     

Anesthesia considerations for lung volume reduction surgery

Patient selection is of crucial importance for outcome after lung volume reduction surgery. The anesthesiologist should be involved actively in patient selection, because he or she is in charge of the treatment during the critical perioperative period. Patient history and status and results from chest radiographs, high-resolution CT scans, and catheterization of the right heart should be taken carefully into account in the patient selection process. Promising new results involving functional parameters may predict outcome objectively after lung volume reduction surgery in the future. Careful selection and preoperative preparation of patients also are important to avoid complications and keep the success rate high. The anesthesiologist's understanding of the principles involved is important for the successful conduct of lung volume reduction surgery. It is unclear if lung volume reduction surgery is superior to conventional therapy in the long run because the decline in lung function is progressive after the procedure. A multicenter trial comparing patients undergoing lung volume reduction surgery with patients with emphysema who are treated conventionally hopefully will clarify this important question in the future.     

Operative techniques for lung volume reduction surgery

Recently, LVRS has received renewed public interest. Various surgical approaches and techniques exist, and each has challenges, advantages, and disadvantages. Stapled techniques have been used more commonly than plication techniques or lasers. The choice of staple buttressing material has not been shown to affect outcome. For most patients who are suitable for LVRS, a bilateral procedure is appropriate. Minimally invasive techniques are gaining in popularity and have demonstrated good results. Of the approaches discussed above, bilateral thoracoscopy in the supine position is likely to be the most expeditious with the lowest incision-related morbidity and dysfunction.     

Patient selection for lung volume reduction surgery

LVRS represents a valid surgical option for a limited number of patients who have symptomatic emphysema. The results of recent controlled studies have provided a realistic view of LVRS outcomes and yielded a validated algorithm for selection of optimal candidates for surgery. Furthermore, the NETT has provided simultaneously collected cost data that have provided a unique view of the costs and benefits of LVRS in patients who have advanced emphysema. Additional data collection will better define the long-term benefits of such surgical intervention in patients who have COPD.     

Thoracoscopic lung volume reduction surgery for emphysema

Thoracoscopic lung volume reduction surgery was conducted in 28 consecutive patients (bilateral 21, unilateral 7). The bilateral procedure was conducted simultaneously in 16 and as a planned staged approach in 5, using stapler resection with Nd: YAG laser ablation. Perfusion and ventilation scintigraphy were used to evaluate status before and after surgery. One operative death (3.6%) due to pneumonia occurred after a simultaneous bilateral procedure. Three to 6 months after surgery, the forced expiratory volume in 1 second (FEV_1.0) had improved an average of 44% after the bilateral procedure and 17% after unilateral. Improved ventilation and perfusion distribution in the lower lung field correlated significantly with improved dyspnea scale (p < 0.01). Mean transit time was shortened significantly in each lung field (p < 0.01). Improved mean transit time correlated significantly with improved FEV_1.0 and maximum oxygen consumption ( $\dot Vo_2 \max$ ) (p < 0.05). In conclusion, we found that bilateral thoracoscopic lung volume reduction surgery produces short-term functional outcomes superior to those of the unilateral procedure, and should be considered the procedure of choice for most patients. Ventilation and perfusion scintigraphy are useful both in determining target areas for resection and in evaluating lung volume reduction surgery effects.     

Anesthetic considerations for lung volume reduction surgery and lung transplantation

Anesthetic considerations for lung transplantation and LVRS have been reviewed, with an emphasis on critical intraoperative junctures and decision points. Cognizance of these issues promotes coordinated and optimal care and provides the potential to improve outcome in this particularly high-risk population.     

Results of lung volume reduction surgery for emphysema

LVRS provides an exciting opportunity for palliation of symptoms and improvement in quality of life for patients who have severe end-stage emphysema. Because no medical therapy has been able to improve pulmonary function or reverse the inexorable decline of breathless patients who have emphysema, this opportunity to improve lung function and quality of life is one of the most innovative additions to thoracic surgery since the first successful lung transplant procedure 20 years ago. Although initial short-term, case-controlled surgeries were criticized because of incomplete and short follow-up care, substantial long-term data now exist to support the use of LVRS for select patients who have severe emphysema. Patients who have upper lobe predominant disease or low exercise capacity are more likely to have a benefit in exercise capacity and quality of life after LVRS. Selected patients who have upper lobe emphysema and poor exercise capacity are also more likely to have improved survival after LVRS. The individual contributions by the large number of investigators pioneering LVRS development, along with the collective contributions of the NETT investigators, have propelled the knowledge surrounding LVRS far beyond that of any similar new technology or procedure in its adolescence.     

Complications after lung volume reduction surgery

LVRS has greater morbidity than most general thoracic surgical procedures. Proper care of patients after LVRS is a labor-intensive activity, but it is worthwhile because LVRS can be performed with acceptable risk. Patient selection, postoperative care, and an understanding of the potential complications are the keys to successful LVRS.     

Complications of lung volume reduction surgery

Lung volume reduction surgery (LVRS) continues to stimulate controversy and spirited discussion. The purpose of the operation is to palliate dyspnea and improve functional status and quality of life for highly selected patients with emphysema. The value of LVRS as a palliative procedure is clearly dependent on the surgeon's ability to minimize the frequency and severity of postoperative complications. This article investigates the sources of morbidity and mortality after LVRS and reports techniques to avoid and manage such complications.     

Awake nonresectional lung volume reduction surgery

OBJECTIVE: To assess the feasibility, safety, and early results of awake lung volume reduction surgery (LVRS) performed under thoracic epidural anesthesia by a new nonresectional technique. SUMMARY BACKGROUND DATA: So far, resectional LVRS under general anesthesia and one-lung ventilation is the more frequently used technique, but procedure-related morbidity has been considerable. METHODS: The study cohort included 12 patients undergoing unilateral awake LVRS. Evaluated parameters included technical feasibility and anesthesia satisfaction scored into 4 grades (from 1 = poor to 4 = excellent), global operating room time, and arterial carbon dioxide tension (PaCO2). In addition, 6-month changes in outcome measures, including forced expiratory volume in 1 second (FEV1), residual volume (RV), 6-minute walking test (SMWT), and dyspnea index were recorded. Perioperative and 6-month results were comparable with those of a control group undergoing unilateral resectional LVRS. RESULTS: Technical feasibility was excellent to satisfactory in 11 patients. One patient required conversion to one-lung ventilation. Differences between the awake and control group included global operating room time (90 +/- 17 minutes versus 145 +/- 19 minutes, P < 0.00001); PaCO2 24 hours after surgery (45 +/- 6 mm Hg versus 49 +/- 6 mm Hg, P = 0.02); and hospital stay (7.8 +/- 5 days versus 11.7 +/- 4 days, P = 0.02). Significant (P < 0.002) improvements occurred at 6 months in FEV1 (0.31 +/- 0.17 L), RV (-1.41 +/- 0.7 L), SMWT (73 +/- 25 m), and dyspnea index (-1.3 +/- 0.5) and were comparable with those of the control group. CONCLUSIONS: In this study, awake nonresectional LVRS proved feasible and safe. This new modality was associated with a faster recovery and satisfactory 6-month outcome, which did not differ from that of resectional LVRS.     

Radiologic assessment of emphysema for lung volume reduction surgery

Radiologic imaging is vital to determining whether lung volume reduction surgery (LVRS) is a potential therapeutic option for patients with severe chronic obstructive pulmonary disease. The importance of imaging in patient selection for LVRS has been emphasized by numerous studies relating preoperative imaging features to postoperative outcomes. This article reviews the radiologic features assessed in the LVRS evaluation, summarizes the relationships between preoperative radiologic features and postoperative outcomes, and addresses the limitations of imaging in guiding patient selection.     

Cost effectiveness of lung volume reduction surgery

Lung volume reduction surgery (LVRS) is a costly new procedure that could influence quality of life and survival for persons who have severe emphysema. This article reviews the history of LVRS from an economic and policy perspective and provides estimates of the cost effectiveness of LVRS derived from the National Emphysema Treatment Trial, a recently completed multicenter evaluation of LVRS, compared with medical care. Estimates of the potential impact of LVRS on the national health care budget are provided. The high cost and uncertainty regarding the long-term cost effectiveness of LVRS warrant further evaluation after public and private health insurers make coverage decisions for this procedure, particularly if it is adopted as part of the standard of care.     

肺减容手术治疗重度肺气肿的临床研究

目的评价肺减容手术对重度肺气肿患者的疗效。方法36例重度肺气肿患者行肺减容手术,双侧8例,单侧28例。术前、术后3、6个月分别测量动脉血气(PaO2,PaCO2)、肺功能(FEV1、RV、TLC)、6分钟运动试验(6-MWD),并对其结果进行比较分析。结果本组无手术死亡,均痊愈出院;术后动脉血氧分压比术前明显提高(P<0.05),二氧化碳分压比术前明显降低(P<0.05);术后3、6个月的FEV1、6-MWD较术前有明显提高(P<0.05),RV、TLC较术前有明显降低(P<0.05);呼吸困难指数再分级,26例术前Ⅲ级中10例转为Ⅰ级,16例转为Ⅱ级;10例Ⅳ级中3例转为Ⅰ级,5例转为Ⅱ级,2例转为Ⅲ级。结论重度肺气肿患者选择性手术,能改善患者肺功能,提高生活质量。     

Limitations of randomized clinical trials for evaluating emerging operations: the case of lung volume reduction surgery

Although unanswered questions remain, scores of observational studies and several small randomized clinical trials (RCTs) indicate that lung volume reduction surgery (LVRS) offers safe and effective palliation for a relatively well defined subset of patients with advanced emphysema. Nonetheless, Medicare and other insurers stopped reimbursement for the procedure. Subsequently, two multicenter RCTs on LVRS, the National Emphysema Treatment Trial (NETT) and the Overholt-BlueCross Emphysema Surgery Trial (OBEST), were launched with the stipulation that the procedure would not be paid for outside these trials. Thus access to LVRS has been denied to patients who could benefit but do not wish to participate in an RCT. Emerging operations, unlike new drugs or devices, pass through evolutionary changes and frequently fail to produce data that meet the scientific rigor required by randomized studies. In such a setting, the observational approach is more appropriate. Indeed, almost all operations in the present surgical armamentarium have been evaluated and have evolved through observational studies without the use of RCTs. By the time new operations are standardized and qualify for RCTs, benefits for certain patients may be demonstrated and randomization could involve unacceptable health hazards. Patients from this population should be offered the choice between participating in RCTs and having the operation outside the study. Imposition of financial restrictions that bars access to a therapy with known benefit is a questionable practice.