肺移植供肺保护进展

肺移植成为终末期肺病的惟一治疗手段。然而其死亡率仍高于其他实质器官移植,供肺保存过程中损伤机制的探讨与保存方法的改进将有利于提高生存率。     

Pulmonary Resection for Lung Trauma

Background. Pulmonary resection is rarely required for trauma, and its mortality is reportedly high.

Methods. A 10-year retrospective review of pulmonary resections for trauma was done.

Results. Of 2,455 patients with chest trauma, 183 (7.4%) underwent thoracotomy and 32 (1.3%) required pulmonary resection. Mean age was 28.4 years and mean injury severity score was 24.5. Mechanism of injury was stab wound in 14 patients, gunshot wound in 6, and blunt trauma in 12. Blunt trauma patients had a higher injury severity score (29.6) than penetrating trauma patients (21.4), but this was not significant (p < 0.07). Indications for thoracotomy were hemorrhage in 24 patients, airway disruption in 4, and other indications in 4. Operations consisted of wedge resection (19 patients), lobectomy (9), and pneumonectomy (4). Four (12.5%) patients (pneumonectomy, 2; lobectomy, 1; wedge, 1) died. Mortality for pneumonectomy was 50%, but this was not significantly higher than for lesser resections. Blunt trauma had a higher mortality (33%) than penetrating trauma (0%) (p < 0.02). Nonsurvivors had higher injury severity scores (44.2) than survivors (21.6) (p < 0.001).

Conclusions. Pulmonary resection is infrequently required for lung injury. Overall mortality is lower than previously reported, but pneumonectomy has a high mortality. Blunt trauma has a higher mortality than penetrating trauma. Injury severity scores are higher for nonsurvivors than survivors; this shows the importance of associated injuries on outcome.     

Effect of Bovine Pericardial Strips on Air Leak After Stapled Pulmonary Resection

Background. Surgical procedures for emphysema have been proposed and in many settings resulted in significant improvement in dyspnea and function. The most prevalent surgical problem in all series is prolonged postoperative air leak.

Methods. One hundred twenty-three patients undergoing stapled thoracoscopic unilateral lung volume reduction operation were prospectively randomized to receive either no buttressing of their staple lines or buttressing of all staple lines with bovine pericardial strips.

Results. The two groups were comparable in preoperative risks and in the severity of their emphysema. Postoperative complications were identical in the two groups with respect to pneumonia, empyema, and wound infection; however, there was a significant difference in the duration of postoperative air leaks. Those having the pericardial strips used to buttress their staple lines had chest tubes removed 2.5 days sooner and were discharged from the hospital 2.8 days sooner as a result. The cost data revealed that because of the cost of the pericardial sleeves, the overall hospital charges were almost identical for the two groups ($22,108 bovine, $22,060 no bovine) in spite of the shortened hospital stay.

Conclusions. The use of bovine pericardial sleeves to buttress the staple lines in thoracoscopic unilateral lung volume reduction operation results in a shorter duration of postoperative air leaks. Total hospital charges were comparable in the two groups as the 2.8 days saved in the hospital were offset by the cost of the pericardial sleeves.     

Heterotopic lung transplant: a feasible approach to compensate for organ shortages

Lung transplants are still limited by the shortage of suitable donor lungs, especially during the coronavirus disease 2019 pandemic. A heterotopic lung transplant (HLTx), as a flexible surgical procedure, can maximize the potential of donor lungs in an emergency, but its widespread use is hindered by difficulties in anastomosis and paucity of outcome data. We performed a retrospective review of 4 patients, each of whom received an HLTxs over 1 year, including 1 left-to-right single HLTx, 2 right-to-left single HLTxs and 1 lobar HLTx (right upper lobe-to-left). The median recipient age was 58.5 years (46–68); 3 patients were male. The postoperative hospital stay was 33 days (30–42). One recipient lived for 10 years and died of bronchiolitis obliterans syndrome; the others were alive with no major morbidity at 12 to 31 months after the operation with a 1-year survival of 100%. The follow-up chest images showed that transplanted lungs could be inflated well and adapted morphologically to fill the thoracic cavity in the short and long term. This study demonstrates that an HLTx is a feasible alternative to a conventional lung transplant in emergency cases and could be considered in selected patients at advanced medical centres.     

Alveolar recruitment in acute lung injury

Alveolar recruitment is one of the primary goals of respiratorycare for acute lung injury. It is aimed at improving pulmonarygas exchange and, even more important, at protecting the lungsfrom ventilator-induced trauma. This review addresses the conceptof alveolar recruitment for lung protection in acute lung injury.It provides reasons for why atelectasis and atelectrauma shouldbe avoided; it analyses current and future approaches on howto achieve and preserve alveolar recruitment; and it discussesthe possibilities of detecting alveolar recruitment and derecruitment.The latter is of particular clinical relevance because interventionsaimed at lung recruitment are often undertaken without simultaneousverification of their effectiveness.     

Cardiovascular responses to high-frequency oscillatory ventilation during acute lung injury in sheep

Purpose The present study was designed to evaluate pulmonary and systemic hemodynamics and blood gas changes on switching from conventional mechanical ventilation (CMV) to high-frequency oscillatory ventilation (HFOV) in a large animal model of acute lung injury. Methods Eleven anesthetised sheep chronically instrumented with vascular monitoring were prepared. Animals received oleic acid (0.08 ml·kg⁻¹) intravenously and were ventilated for 4 h h after the administration of oleic acid. The animals were then randomized into the two following different ventilation modes: CMV (tidal volume [V_T], 6 ml·kg⁻¹; respiratory rate [RR], 25 · min⁻¹) with positive end-expiratory pressure (PEEP) of 12 cmH₂O; or CMV under the same settings without PEEP. HFOV was then switched. The setting of mean airway pressure with a fixed stroke volume was changed between 25, 18, and 12 cmH₂O every 20 min. Mean pulmonary artery pressure, pulmonary artery occlusive pressure (Paop), left atrium pressure, systemic arterial pressure, cardiac output (CO), and blood gas composition under each setting were measured before and after HFOV. Results Switching to HFOV, from without PEEP, resulted in significant increases in Paop and PaO2 and a decrease in CO at higher (25, 18 cmH₂O) mean airway pressure. However, when changed from low V_T and PEEP, HFOV produced further improvements in oxygenation without any deterioration of cardiovascular depression. Thus, switching to HFOV from CMV with low V_T and high PEEP may have little influence on pulmonary or systemic hemodynamics in acute lung injury. Conclusion We conclude that hemodynamic responses are dependent on the predefined setting of PEEP during CMV, and on applied mean airway pressure during HFOV.     

Independent lung ventilation for asymmetrical chest trauma: effect on ventilatory and haemodynamic parameters

Complex thoracic injuries significantly alter the lung mechanics. There appears to be severe ventilation-perfusion inequality that is enhanced by the asymmetrical compliance of the injured areas. In cases of unilateral massive air leaks large tidal volumes are needed to deliver adequate air volume to the injured lung. In such cases, mechanical ventilation via a standard tracheal tube will direct a large fraction of the tidal volume to the less affected areas. An alternative means of ventilating these patients is the application of independent lung ventilation through a double lumen tracheal tube and the use of two separate ventilators. Two such cases are presented with emphasis given on the ventilatory and haemodynamic changes that were recorded.     

Total and prolonged filling of the lungs with Ringer's solution under extracorporeal lung assist (ECLA) in dogs

BACKGROUND: Massive alveolar lavage has been used clinically to remove materials accumulated in the alveoli. Recently, filling the lungs with oxygenated perfluorochemical (total liquid ventilation) has been investigated. However, effects of complete and prolonged filling of bilateral lungs with aqueous fluid, such as saline or Ringer's solution, has not been evaluated, although it is possible to sustain gas exchange without the natural lung by using extracorporeal circulation and an artificial lung (extracorporeal lung assist: ECLA). It is also not known whether the lung can recover gas exchange ability after prolonged fluid filling. METHODS: Normal mongrel dogs were endotracheally intubated under general anesthesia and mechanically ventilated. After initiation of venoarterial ECLA, warmed lactated Ringer's solution was instilled into the lungs through the endotracheal tube, and the lungs were completely filled at a hydrostatic pressure of 15 cmH2O (fluid-filled group: group F). After the lungs were filled for 4 h, the fluid was drained and ventilation was re-instituted. ECLA, then mechanical ventilation was gradually weaned within 24 h after fluid drainage. In control group (group C), dogs were kept apneic for 4 h with their lungs inflated at an airway pressure of 15 cmH2O with air. RESULTS: Transient hypoxemia occurred during fluid filling but every dog could be weaned from ECLA and mechanical ventilation to spontaneous respiration. The average rate of fluid absorption from the lung during fluid filling was 4.2+/-1.8 ml kg(-1) h(-1). After fluid drainage and restart of mechanical ventilation, bilateral lungs were expanded and well aerated. Total static respiratory system compliance (static compliance) remained unchanged even after fluid filling, and the weight of the lung water did not increase significantly compared to that in group C. Total urine volume was significantly increased in group E Histologically, alveolar structures were preserved and no interstitial edema or bleeding was seen in either group. CONCLUSION: Complete filling of the bilateral lungs for 4 h with lactated Ringer's solution under ECLA causes no deterioration in gas exchange or static compliance in normal dogs, although transient hypoxemia occurs during fluid filling.     

Artificial lungs––Where are we going with the lung replacement therapy?

Lung transplantation may be a final destination therapy in lung failure, but limited donor organ availability creates a need for alternative management, including artificial lung technology. This invited review discusses ongoing developments and future research pathways for respiratory assist devices and tissue engineering to treat advanced and refractory lung disease. An overview is also given on the aftermath of the coronavirus disease 2019 pandemic and lessons learned as the world comes out of this situation. The first order of business in the future of lung support is solving the problems with existing mechanical devices. Interestingly, challenges identified during the early days of development persist today. These challenges include device-related infection, bleeding, thrombosis, cost, and patient quality of life. The main approaches of the future directions are to repair, restore, replace, or regenerate the lungs. Engineering improvements to hollow fiber membrane gas exchangers are enabling longer term wearable systems and can be used to bridge lung failure patients to transplantation. Progress in the development of microchannel-based devices has provided the concept of biomimetic devices that may even enable intracorporeal implantation. Tissue engineering and cell-based technologies have provided the concept of bioartificial lungs with properties similar to the native organ. Recent progress in artificial lung technologies includes continued advances in both engineering and biology. The final goal is to achieve a truly implantable and durable artificial lung that is applicable to destination therapy.     

Coexistence of lung cancer and hamartoma

We present a rare case of a synchronous primary lung cancer adjacent to a hamartoma. A 71-year-old woman was admitted with congestive heart failure due to acute myocardial infarction. A chest radiogram on admission showed pulmonary edema with a tumor shadow in the right upper lung field. Because histological diagnosis was not obtained preoperatively, a wedge resection of the lung was conducted using video-assisted thoracoscopic surgery. The histopathological examination confirmed the coexistence of an adenocarcinoma with a chondromatous hamartoma. Right upper lobectomy was performed followed by excision of the mediastinal lymph nodes. Although hamartoma is generally considered to be a benign neoplasm, there have been several reports of increased risk to lung cancer in patients with a chondromatous hamartoma. Therefore, we recommend that patients with a hamartoma should be submitted to a complete evaluation and to regular follow-up, considering the risk to associated synchronous malignancy.     

Early treatment with arteriovenous extracorporeal lung assist and high-frequency oscillatory ventilation in a case of severe acute respiratory distress syndrome

BACKGROUND: Lung protective ventilation can reduce mortality in acute respiratory distress syndrome (ARDS). However, many patients with severe ARDS remain hypoxemic and more aggressive ventilation is necessary to maintain sufficient gas exchange. Pumpless arteriovenous extracorporeal lung assist (av-ECLA) has been shown to remove up to 95% of the systemic CO(2) production, thereby allowing ventilator settings and modes prioritizing oxygenation and lung protection. High-frequency oscillatory ventilation (HFOV) is an alternative form of ventilation that may improve oxygenation while limiting the risk of further lung injury by using extremely small tidal volumes (VT). METHODS: We discuss the management of a patient suffering from severe ARDS as a result of severe bilateral lung contusions and pulmonary aspiration. RESULTS: Severe ARDS developed within 4 h after intensive care unit admission. Conventional mechanical ventilation (CV) with high-airway pressures and low VT failed to improve gas exchange. Av-ECLA was initiated to achieve a less aggressive ventilation strategy. VT was reduced to 2-3 ml/kg, but oxygenation did not improve and airway pressures remained high. HFOV (8-10 Hz) was started using a recruitment strategy and oxygenation improved within 2 h. After 5 days, the patient was switched back to CV uneventfully and av-ECLA was removed after 8 days. CONCLUSION: The combination of two innovative treatment modalities resulted in rapid stabilization and improvement of gas exchange during severe ARDS refractory to conventional lung protective ventilation. During av-ECLA, extremely high oscillatory frequencies were used minimizing the risk of baro- and volutrauma.     

Native lung complications after single lung transplantation for emphysema

We reviewed the impact of the presence of the native diseased contralateral lung on the outcome after single lung transplantation for emphysema. Twenty consecutive recipients of single lung transplants for emphysema were reviewed for complications related to the native lung. Five patients (25 %) suffered major complications arising in the native lung and resulting in serious morbidity and mortality. The timing of onset varied from 1 day to 43 months after transplantation. We conclude that the susceptibility of the native lung to complications such as those described in this report is an additional fact to be considered in choosing the ideal transplant procedure for patients with obstructive lung disease. Received: 2 July 1996 Received after revision: 15 October 1996 Accepted: 28 October 1996     

门诊-居家康复运动对肺叶切除术患者身体活动量的影响

目的探讨门诊-居家康复运动对肺癌行肺叶切除术患者身体活动量的影响。方法将行肺叶切除术的肺癌患者52例按随机数字表法分为对照组和观察组各26例,对照组按常规进行出院健康指导及电话随访,观察组出院时行常规出院健康指导及实施为期8周的门诊-居家康复运动。比较两组术前及出院后8周的身体活动量、肺功能。结果对照组出院后8周身体活动量级和每日身体活动时间显著低于术前(均P0.05);出院后8周观察组身体活动量级和每日身体活动时间显著高于对照组(均P0.01);对照组出院后8周FVC、FEV1和MVV值显著低于术前(均P0.05);观察组出院后8周的FVC、FEV1和MVV值高于对照组,但差异无统计学意义(均P0.05)。结论对肺癌行肺叶切除术患者行门诊-居家康复运动,可提高患者身体活动量,促进肺功能康复,有利于加快患者机体康复进程。     

One and One-Half Year Experience with Unilateral and Bilateral Lung Transplantation

Lung transplantation has now become an established form of treatment for end-stage pulmonary parenchymal and vascular diseases. Despite its wide acceptance, technical aspects are still in discussion. We report on the initiation of our own lung transplant program and the technical changes we have performed during our first 1 1/2-year experience. During that period of time, we have performed 26 lung transplantations (16 single lung [SLTX] and 10 bilateral lung transplantations [BLTX]). Three-month survival for the whole group was 74% (69% for the SLTX group and 77% for the BLTX group). No instance of bronchial dehiscence was observed; however, there were eight cases of bronchial stenosis: six were managed by silicone stent insertion, one by bronchoplastic correction, and one by retransplantation. Changes in the technique of the bronchial anastomosis together with the addition of prednisone to the immediate postoperative immunosuppressive regime resulted in almost complete avoidance of these problems.     

Other conditions of the lung (abscesses,inhaled foreign bodies,bullous lung disease,hydatid)

Lung abscess remains a common complication of pneumonia and aspiration, particularly in immunosuppressed patients and must be differentiated from a cavitary form of lung cancer. The conservative treatment with antibiotics is still the main therapeutic approach; however, percutaneous drainage may be employed in selected cases. Inhaled foreign bodies require a prompt diagnosis with rigid or a combination of rigid and flexible bronchoscopies to remove the foreign body avoiding complications and the need for a thoracotomy. Bullous lung disease is a common pathology mainly developing as a result of emphysema. Occasionally congenital or acquired lung cysts are diagnosed. Surgical bullectomy is the treatment of choice but external drainage may be indicated in patients with a limited functional reserve. Hydatid lung disease is caused by Echinococcus affecting most commonly the liver and lung. Resection of the cystic lesions may be necessary to eliminate the symptoms and to prevent further complications.