Venous velocity of the right femoral vein decreases in the right lateral decubitus position compared to the supine position: a cause of postoperative pulmonary embolism?

The right lateral decubitus position is a risk factor for postoperative pulmonary embolism. We examined postural changes of femoral vein velocity in order to elucidate the mechanism. Thirty patients scheduled for general thoracic surgery were enrolled in this study. The common femoral veins on both sides were examined by color-duplex ultrasound for venous caliber and velocity when the patients were in the right lateral, left lateral, and supine positions. The maximum diameters of the right femoral vein in the right lateral decubitus position and the left femoral vein in the left decubitus position were significantly larger than those in the other positions. The venous velocity of the right femoral vein in the right lateral decubitus position was significantly smaller than that in the supine position, while the velocity of the left femoral vein in the left lateral decubitus position was not significantly decreased. We speculate that the decreased venous velocity of the right femoral vein in the right lateral decubitus position could result in a deep venous thromboembolism in the right leg, making this position a possible risk factor for postoperative pulmonary embolism.</p

Optimal Temperature of Graft Preservation after ex Vivo Gene Transfer in Lung Isografts

The aim of this study was to determine the optimal temperature of graft preservation after ex vivo gene transfer to rat lung isografts. Left lungs were harvested and infused with cationic lipid/LacZ-DNA complex via the pulmonary artery, and the grafts were stored for 4h. The grafts (n＝7) were allocated into groups IﾝIV according to the storage temperature:4℃, 10℃, 16℃, and 23℃, respectively. Forty-eight h after orthotopic transplantation, the arterial blood gas was analyzed and the peak airway pressure (PAP) and the level of LacZ protein production in the grafts were measured by reverse transcription polymerase chain reaction. After reperfusion, the grafts were stained with hematoxylin and eosin. The grafts in groups III and IV showed more deterioration as evidenced by decreased arterial oxygen tension, increased PAP, and predominant infiltration of inflammatory cells compared with groups I and II. The level of LacZ production was significantly lower in group I than in groups IIﾝIV. The optimal temperature of lung graft preservation after ex vivo gene transfer was determined to be 10℃, balancing considerations of lung injury and efficiency of transgene expression.</p

Experimental study on size matching in a canine living-donor lobar lung transplant model

AbstractObjective: In an effort to address the donor-shortage issue, living-donor lobar lung transplants have been performed with satisfactory results. The use of small grafts is potentially problematic because it could cause high pulmonary artery pressure, resulting in lung edema. The purpose of this study was to evaluate the effect of small grafts on early pulmonary function and to identify the predictor for acceptable size discrepancy. Methods: Seventeen pairs of mongrel dogs with various donor-recipient sizes were used. Body weight, height, chest circumference, and lung weight were measured as size parameters. Right middle, lower, and cardiac lobes were implanted as a right lung of the recipient and the left lower lobe was implanted as a left lung without use of cardiopulmonary bypass. Pulmonary function of the recipient was measured for 6 hours after reperfusion. Results: A significant negative correlation was found between donor/recipient body-weight ratio and mean pulmonary artery pressure at 1 hour (r = –0.594, P =.025). A significant correlation was found between donor/recipient body-weight ratio and PaO2 at 6 hours (r = 0.704; P =.007). There was no significant correlation between the other 3 size parameters and postoperative pulmonary function. All 8 recipients with a donor/recipient body-weight ratio of 1.2 or greater survived the 6-hour assessment period, and their PaO2 exceeded 500 mm Hg at 6 hours. Conclusions: Donor/recipient weight ratio is an important predictor of early pulmonary function in a canine living-donor lobar lung transplant model

Tracheal Stenosis Caused by Unnoticed Foreign Bodies

We describe an extremely rare case of tracheal stenosis caused by unnoticed microscopic fiber-like foreign bodies. A 66-year-old woman complained of dyspnea with inspiratory stridor. Magnifying electroendoscopy and computed tomography revealed stenosis involving the entire circumference of the tracheal lumen. Tracheotomy and biopsy were performed. Histologically, the lesion showed chronic inflammation with a deposition of fiber-like foreign bodies. The patient had no history of trauma or inhalation injury, but had undergone intratracheal intubation on 4 occasions. The lesion was incised using semiconductor laser photoresection, and the postoperative course was good. To the best of our knowledge, this represents the first report in the English literature of tracheal stenosis caused by unnoticed foreign bodies. The origin of these fiber-like foreign bodies remains unclear but might be related to chronic inflammation resulting from intratracheal intubations

Improved survival after living-donor lobar lung transplantation

ObjectiveSurvival after living-donor lobar lung transplantation has been reported to be similar to that after cadaveric lung transplantation. The purpose of this study was to summarize our 5-year experience of living-donor lobar lung transplantation for critically ill patients.MethodsBetween October 1998 and April 2004, we performed living-donor lobar lung transplantation in 30 critically ill patients with various lung diseases, including 5 (17%) patients on a ventilator. Mean age was 30.4 years (range, 8-55 years). Postoperative management included slow weaning from a ventilator, relatively low-dose immunosuppressants, and careful rejection monitoring on the basis of radiographic and clinical findings without transbronchial lung biopsy.ResultsThe average duration of mechanical ventilation was 15.4 days, intensive care unit stay was 23.5 days, and hospital stay was 64.6 days. Clinically judged acute rejection occurred at an average rate of 1.5 episodes per patient, but infection occurred in only one patient during the first month. In spite of the complicated postoperative course, all patients were discharged without oxygen inhalation. Four patients had unilateral bronchiolitis obliterans syndrome, but the decrease in their forced expiratory volume in 1 second values stopped within 9 months. All 30 recipients are currently alive, with a follow-up period of 1 to 66 months. All donors have returned to their previous lifestyles.ConclusionsLiving-donor lobar lung transplantation can be applied to both pediatric and adult patients with very limited life expectancies. It might provide better survival than conventional cadaveric lung transplantation