Norikazu Urabe

Surgery for secondary spontaneous pneumothorax: risk factors for recurrence and morbidity

OBJECTIVES Secondary spontaneous pneumothorax (SSP) is more common in elderly patients; it has high rates of recurrence and mortality, even if surgery is performed. There has been little study on the surgical treatment of SSP. Therefore, we analysed the outcomes of surgical treatment of SSP patients, and investigated the risk factors of recurrence and morbidity. METHODS We studied 97 consecutive surgical treatments on 94 patients with SSP who had emphysematous changes of lung retrospectively. Emphysematous changes on preoperative computed tomography image were evaluated by the Goddard score, which is a visual scoring system. First, video-assisted thoracoscopic surgery was performed, followed by bullectomy for the responsible lesions. RESULTS The rate of morbidity was 20.6% and that of mortality was 4.1%. Recurrence rate was 9.3%. By multivariate analysis, a Goddard score≥7 (odds ratio: 8.93, P=0.033) and treatment of bulla without the use of staplers (odds ratio: 11.57, P=0.019) were significant risk factors for morbidity, while pulmonary fibrosis tended to increase the risk of recurrence (hazard ratio: 4.21, P=0.051), and a Goddard score≥7 (hazard ratio: 7.79, P=0.023) was a significant risk factor for recurrence. CONCLUSIONS Surgical treatment in patients with SSP had favourable results. Treatment in which the base of the bulla cannot be definitely shut off with staplers is associated with increased morbidity. Significant emphysematous change on preoperative computed tomography image and pulmonary fibrosis are predictors of recurrence. Patients with these findings should be investigated in terms of the indications of surgery and additional treatment, not only bullectomy.

Dose study of the immunosuppression of FK 506 in canine lung allo-transplantation

The immunosuppressive effect of FK506 (FK) in comparison to cyclosporine A (CsA) on lung graft rejection was demonstrated using 24 mongrel dogs with left lung allotransplanatation. The cytotoxic activity of peripheral blood mononuclear cells was evaluated using donor skin fibroblasts. In eight dogs not given immunosuppression, the grafted lungs lost aeration 5–10 days postoperatively, and histologic findings revealed grade II rejection and cytotoxic activity elevated to between 10.7 and 60.5%, being an average of 31.2% at an effector/target (E/T) ratio of 50. Of 12 dogs treated with FK, none demonstrated a cytotoxic activity of 10% or more at an E/T ratio of 50. Moreover, histologic examinations of the specimens obtained by open chest biopy revealed no signs of rejection during the first 10 postoperative days of FK administration, except in one dog showing grade I rejection from the FK 0.05 mg/kg group. A dose study of the duration until the onset of graft rejection and the elevation of cytotoxic activity after the termination of FK administration revealed approximately 1–2 weeks in the FK 0.05 mg/kg group, 3–4 weeks in the 0.1 mg/kg group, and later in the 0.4 mg/kg and 2.0 mg/kg groups. However, severe body weight loss was seen in the 0.4 mg/kg and 2.0 mg/kg groups postoperatively, without recovery even after the termination of FK. In fact, two dogs died of pneumonia possibly derived from general emaciation. These results suggest the optimal concentration of FK in canine lung allo-transplantation to be 0.1 mg/kg intramuscularly.

Acute empyema with intractable pneumothorax associated with ruptured lung abscess caused by Mycobacterium avium.

Nontuberculous mycobacterial lung disease rarely features pleural involvement. Therapeutic strategies for this situation have not been well established. We present a case of acute empyema with intractable pneumothorax associated with ruptured lung abscess caused by Mycobacterium avium in an immunocompromised patient. Combined treatment that included multidrug antibiotic therapy and nonresectional surgery resulted in a good outcome.

Secondary spontaneous pneumothorax associated with emphysema and ruptured bullae at the azygoesophageal recess

PurposeWith secondary spontaneous pneumothorax (SSP) associated with emphysema, lesions responsible for pneumothorax can be located anywhere along the lung surface. Among such lesions, ruptured bullae at the azygoesophageal recess (AER) have received little attention thus far.MethodsWe conducted a retrospective study of 38 right SSP patients with emphysema who underwent surgery. Among them, we reviewed the clinical characteristics and technical problems of patients with surgically proven ruptured bullae at the AER.ResultsRuptured bullae at the AER were found in 10 of 38 patients. They accounted for 26.3% of all 38 patients and for 66.7% of 15 patients whose bullae at the AER were identified by preoperative computed tomography (CT). On CT, all the bullae were relatively large and oriented in a predominantly vertical axis. At surgery, they were confirmed as white, thin-walled structures originating from the mediastinal part of the apical segment of the right lower lobe. Surgery typically consisted of stapling bullectomy with video-assisted thoracic surgery. Technical problems in surgical treatment included poor mobilization of the base of the bulla and a restricted working space.ConclusionBullae at the AER are common and possibly lead to rupture. The presence of a bulla at the AER seen by CT can be predictive of rupture. Although the AER is a unique location, video-assisted bullectomy is the method of choice for treating these lesions.

Factors influencing survival after endoscopic Nd:YAG laser surgery for unresectable advanced malignancies of the trachea

The effects of endoscopic Nd:YAG laser surgery were studied in 36 patients with unresectable advanced primary and metastatic malignancies in the trachea with special reference to the factors influencing long-term survival. Overall effectiveness of YAG laser treatment was demonstrated in 34 of the 36 patients (94 per cent), while the overall 1, 3 and 5 year survival rates after the first laser treatment were 25 per cent, 13 per cent and 13 per cent, respectively. Neither histologic type nor the severity of clinical symptoms before laser treatment showed any significant influence on the survival curves, however, endoscopic findings of stenosis, the effect of laser treatment and irradiated longitudinal length were all significantly correlated with the survival curves. In other words, endoscopically protruding type tumors with a longitudinal length of irradiation of 3.0 cm or less, and good responses not only to laser treatment but also to other combined modalities are favorable factors for achieving long-term survival in patients with tracheobronchial malignancies undergoing endoscopic Nd:YAG laser treatment. Endoscopic Nd:YAG laser surgery is considered to be a promising part of the multi-modality treatment for unresectable advanced primary and metastatic malignancies of the trachea.

Morphological rejection phases and cytotoxic activity in peripheral blood lymphocytes in canine lung allo-transplantation

The relationship between the morphological changes in allografted lungs and the cytotoxicity of recipient peripheral blood lymphocytes was studied. Left lung allotransplantations were performed in 14 adult mongrel dogs. Four dogs were treated with cyclosporin A (20 mg/kg/day po.) and four were treated with FK-506 (0.1 mg/kg/day im.) for 10 days. Six dogs were not given any immunosuppressive drugs. Cytotoxicity was measured with the51Cr release assay in which the donor skin fibroblasts were used as target cells. The histological changes of the grafted lungs were classified into three grades: grade 0; no abnormal findings, grade I; perivascular and peribronchial mononuclear cell infiltration, and grade II; edema, hemorrhage and a fibrin-like substance in the alveolar space in addition to the findings of grade I. The grafted lungs of the dogs with elevated cytotoxicity showed the histological findings of grade II (8 of the 14 dogs) and significantly higher cytotoxicity (44.1±25.7 per cent) were seen in these dogs than in those with grade 0 (2.0±3.9 per cent) or grade I (2.6±1.9 per cent). It is therefore considered that the cytotoxicity against donor skin fibroblasts in recipient peripheral blood lymphocytes is associated with morphological rejection phases in allografted lungs.

Utilization of the Walking Oximetry Test to Allow Safe Ambulation After Pulmonary Resection

Abstract Supplemental oxygen therapy after pulmonary resection can generally be tapered according to arterial blood gases at rest or pulse oximetry (SpO2). However, detecting exercise-induced oxygen desaturation can be difficult. We developed the walking oximetry test (WOT) so that thoracotomy patients could be rehabilitated without the risk of undetected ambulatory hypoxemia. The subjects were 58 patients who had undergone pulmonary resection and could walk at the bedside, with oxygen at 3 l/min via a nasal cannula. Patients with a value of more than 100 torr were allowed to walk with assistance for 6 min in the corridor. The oxygen flow rate was kept at 3 l/min and the walking pace was less than 50 m/min. SpO2 was determined using a wristwatch pulse oximeter. The test was stopped if the SpO2 fell below 90% or there was a score of 5 or more on the Borg scale (range 1–10). Oxygen desaturation occurred in six patients (10%) during the WOT. These patients underwent ambulatory training with sufficient oxygen supplementation and were then tested again. Patients whose SpO2 values remained higher than 90% and who showed no more than 5% desaturation were permitted to walk in the corridor with oxygen at 3 l/min via a nasal cannula. All these patients had a Borg score of 4 or lower. The WOT is a reliable, nonvasive method for detecting exercise-induced oxygen desaturation during ambulation after pulmonary resection.

Donor-specific cytotoxic lymphocyte activity from bronchoalveolar lavage during acute canine lung allograft rejection

OBJECTIVE We investigated the relationship between acute lung rejection and donor-specific cytotoxic activity (DSCA) in recipients lymphocytes obtained from bronchoalveolar lavage (BAL). METHODS A total of 26 mongrel dogs underwent left lung allotransplantation. Dogs received either no immunosuppressive treatment (group I), cyclosporine (group II), or cyclosporine and methylprednisolone for evidence of acute rejection (group III). DSCA was measured by a 51Cr release assay, using lymphocytes from BAL samples as effector cells and 51Cr-labeled donor skin fibroblasts as target cells. The pathologic findings of the transplanted lungs were classified according to the working formulation for classification and grading of pulmonary rejection. In addition, the degree of cellular infiltration in the perivascular, peribronchial, interstitial, and intraalveolar areas was determined based on an infiltration score. RESULTS DSCA in BAL samples was elevated during mild, moderate and severe acute rejection. The accuracy of the diagnosis of mild or moderate rejection was 92.3% at effector:target (E:T) ratios of 100:1 and 50:1. The DSCA in the BAL fluid and the total infiltration score were correlated closely with correlation coefficients of 0.859 and 0.828 at E:T ratios of 100:1 in group I and group II dogs, respectively. Lung aeration improved and DSCA decreased with methylprednisolone therapy in three of four dogs with grade 2 rejection. CONCLUSION There is a direct relationship between the DSCA in BAL fluid and the degree of tissue damage caused by acute rejection. The DSCA can be detected by a 51Cr release assay which may hold promise for future clinical applications.