Hideyasu Omiya

A new bioabsorbable sleeve for staple-line reinforcement: report of a clinical experience.

AbstractPurpose. The most frequent and troublesome complication after resection of an emphysematous lung is persistent air leakage. This report describes our recent experience of using sleeves made of polyglycolic acid to reinforce staple-lines to reduce air leaks after resection of emphysematous lung. Methods. We used bioabsorbable sleeves made of polyglycolic acid (PGA) for staple-line reinforcement during lung resections in 25 patients with emphysema. Results. Immediately after stapling, no air leaks were detected in 20 patients (80%), although prolonged air leaks lasting for more than 7 days were observed in three patients (12.5%). Conclusion. PGA sleeves do not constitute a foreign body that stays in the host lung, and they require no rinsing at the time of clinical use. Therefore, the PGA sleeve could be a promising new material instead of non-absorbable materials and xenomaterials for staple-line reinforcement.

Fate of fibrin sealant in pericardial space

BACKGROUND Although fibrin sealant (Beriplast, Aventis Behring, Marburg, Germany) has been widely used as a supplementary measure for hemostasis during cardiac surgery in Europe and is becoming popular in the United States, the pharmocokinetics of fibrin sealant applied in pericardial space has not been elucidated. METHODS A small incision was made on the epicardial surface of the left ventricle of a rat, and the incision was sutured. Total 0.2 ml of fibrin sealant containing iodine 125 (125I)-labeled fibrinogen, aprotinin, blood coagulation factor XIII and thrombin was applied to the area around the suture line. RESULTS Distributions of 125I-labeled fibrinogen in the heart on postoperative days 1, 3, 7, and 14 were 48.2% +/- 1.8%, 20.7% +/- 2.2%, 0.15% +/- 0.02%, and 0.01% +/- 0.02%, respectively. The radioactivity was negligible in the blood, liver, spleen, and kidney except for the thyroid in which the radioactivity increased to 7.9% +/- 0.7% and 4.3% +/- 0.4%, respectively, on postoperative days 7 and 14. Iodine 125-labeled fibrinogen concentrations of the heart and other organs showed a similar change in the time course of distribution. Dense and thick fibrin network, observed on postoperative day 1, had dissipated and was thinner with collagen formation by postoperative day 7. CONCLUSIONS Fibrin sealant applied to the pericardial cavity regresses rapidly and plays an important role in wound healing.

Survival Impact of Pulmonary Metastasis as Recurrence of Pancreatic Ductal Adenocarcinoma

Aim: This study aimed at investigating the survival impact of pancreatic ductal adenocarcinoma (PDAC) recurrence as pulmonary metastasis. Methods: We performed a retrospective case-control study of 142 patients who underwent curative resection for PDAC at our institution between 2003 and 2012. Clinicopathological features were compared among patients stratified according to the recurrence pattern and pulmonary metastasis treatment strategy. Results: Patients underwent pancreaticoduodenectomy (n = 96), distal (n = 42), or total pancreatectomy (n = 4). At the last follow-up, 99 patients had developed recurrent post-resection PDAC, including 14 cases of isolated pulmonary recurrence. The median overall survival was significantly longer for patients with isolated pulmonary recurrence (40.3 months) than with other metastases (20.9 months; HR 5.85; p = 0.0156). Two patients underwent resection for isolated pulmonary recurrence, and both survived for ∼70 months after primary resection. Conclusion: Patients with first recurrence of PDAC as pulmonary metastasis had a better prognosis than patients with other types of metastases. Moreover, when isolated pulmonary metastasis is controlled for a certain period, pulmonary resection is likely to improve patient survival.

The pharmacokinetics of a fibrin adhesive agent applied to the rat lung

PURPOSE Although fibrin adhesive agents are frequently applied in the clinical setting, their pharmacokinetics in vivo remain to be clarified. We examined the pharmacokinetics of a fibrin adhesive agent applied to the rat lung. MATERIAL AND METHODS Male Sprague Dawley rats were used. Under general anesthesia, left thoracotomy was performed, and the left lung was incised about 1 cm length and 1 mm depth. This incision was sutured with 9-0 nylon, and a fibrin adhesive agent containing 125I-labeled fibrinogen was applied. On days 1, 3, 7 and 14 after the operation, the left lung, right lung, liver and kidneys were collected. The tissue distribution of radioactivity was examined by determining the 125I levels in each organ as well as calculating the tissue levels of radioactivity. RESULTS The tissue distribution of radioactivity in the left lung was significantly higher than those in other organs on days 1 and 3. The tissue levels of radioactivity in the left lung was significantly higher than those in other organs on days 1, 3 and 7. Each value rapidly decreased after day 7. CONCLUSION A fibrin adhesive agent applied to the lung significantly remained at a high level through the inflammatory and proliferative phases followed by a prompt decrease before the phase of cicatrization. Therefore it is considered that a fibrin adhesive agent applied to the lung is satisfactory for the healing of wounds.

[An experimental study of local chemotherapy for metastatic lung tumor--isolated lung perfusion and pulmonary artery infusion].

PURPOSE We evaluated the efficacy of local chemotherapy using isolated lung perfusion (ILP) and pulmonary artery infusion (PAI) in vivo to improve prognosis for patients with metastatic lung diseases. MATERIAL AND METHODS Male F344 rats were used. The left lung was isolated and chemotherapeutic agents were administrated to the isolated lung by the ILP or PAI technique. Agents used were cisplatin (CDDP) and fluorouracil (5-FU), and their levels in the perfused lung and serum were measured (renal levels were also measured in CDDP groups). The results were compared with those obtained following intravenous administration (i.v.). In the ILP group, the left pulmonary artery and vein were clamped during perfusion. The agents were infused from the pulmonary artery, and the perfusate was collected from the pulmonary venotomy site following flushing with saline before declamping. In the PAI group, the left pulmonary artery was clamped and perfused with 0.2 ml of the agents, pulmonary arterial flow was occluded for 20 minutes, and perfusate was not collected. Rats were sacrificed 5 minutes after declamping in both groups, and the perfused lung and blood (and also kidneys in the CDDP group) were collected for pharmacokinetic examination. Histological examination of the perfused lung was also performed. RESULTS In the ILP group treated with 1 mg of CDDP and PAI group treated with 0.1 mg of CDDP administration, the lung CDDP levels were significantly higher and the serum and renal CDDP levels were significantly lower than those in the IV group. In the ILP group treated with 150 mg of 5-FU and PAI group treated with 10 mg of 5-FU, the lung 5-FU levels were significantly higher than those in all IV groups and the serum 5-FU levels were lower than those in the IV group treated with 10 mg and 15 mg of 5-FU. The bronchopulmonary construction was histologically maintained in the perfused lung in each group. CONCLUSION We concluded that local chemotherapy using ILP or PAI could be a safe and effective choice of therapy, and this method may be clinically applicable.

Results of surgery for bronchogenic carcinoma located in the aortic window

Because of its critical location, lung cancer located in the aortic window can cause complications affecting the pulmonary artery trunk, aortic arch and esophagus. The results of surgical treatment are poor; however, there are few long-term survivors. In an attempt to define the indications for extended surgery, we evaluated eleven patients with non-small cell lung cancer. The tumors were classified according to their clinical extent of invasion as Type A (invading the anterior mediastinum including the central part of the pulmonary artery), Type B (invading upwardly to the mediastinum through the aortic window) or Type C (invading the posterior mediastinum including the thoracic aorta or esophagus). In the five patients with type A invasion, no metastases to the upper mediastinal lymph nodes other than the subaortic lymph nodes were found. The three patients with type B invasion had many metastases to the upper mediastinal lymph nodes. There were no metastases in the upper mediastinum in any of these patients with type C invasion, but metastases were found in a lower mediastinal lymph node #9, and a carinal lymph node. Each group clearly demonstrated a different site of mediastinal lymph nodes metastasis. The long term result was good in Type A invasion, in contrast to Type B or C invasion. Our classification may be useful for planning ones surgical approach to advanced lung cancer of the aortic window.

Experimental study of pulmonary artery infusion with cisplatin in a solitary pulmonary tumor model using a rat colorectal adenocarcinoma cell line

OBJECTIVES We assessed a tumor model prepared by open lung injection to study metastatic lung tumors, and evaluated the efficacy of pulmonary artery infusion. METHODS Subjects were 30 male F344 rats. In experiment 1, we evaluated chemosensitivity of a rat colorectal adenocarcinoma cell line (RCN-9) using a colorimetric [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. In experiment 2, we injected RCN-9 cells into the left lung on day 0; on day 10, we measured tumor tissue blood flow before and after pulmonary arterial occlusion. In experiment 3, we injected RCN-9 cells into the left lung and conducted no further procedures in controls. The pulmonary artery infusion group underwent pulmonary artery infusion with 0.1 mg of cisplatin on day 3 and the sham group injection with saline solution alone. On day 10, rats were sacrificed and maximum tumor cross-section measured. RESULTS In experiment 1, the drug concentration required to inhibit cell growth 50% was 2.45 x 10(-6) M. In experiment 2, tumor tissue blood flow decreased significantly after arterial occlusion (p = 0.003). In experiment 3, the maximum tumor cross-section in the pulmonary artery infusion group was significantly smaller than in shams (p = 0.0027) and controls (p = 0.0019). CONCLUSIONS The pulmonary artery supplies tumors with blood, so this model appears useful in studying metastatic lung tumors, whose size was reduced significantly by pulmonary artery infusion with cisplatin. Pulmonary artery infusion is thus a promising modality in metastatic lung tumor treatment.