Biomedical subjects
Publications and source records attributed to R Adoumie.
The presence of a horseshoe kidney may complicate surgery of the aorta. Abnormal renal anatomy, blood supply, and difficult exposure related to a bulky isthmus are commonly encountered. We describe a case where a left retroperitoneal exposure was successfully used to simplify many of these difficulties.
A temporary increase in pulmonary vascular resistance is observed during the first 24 hr following lung allotransplantation. We hypothesized that such early vascular changes are secondary to endothelial injury by ischemia-reperfusion, and that this may be mediated by an increased pulmonary endothelin-1 production/release. To test this hypothesis, radioimmunoassay was used to analyze endothelin-1 levels in bronchoalveolar lavage and plasma taken before surgery and at 1 hr, 4 hr, 24 hr, and 1 week after transplantation. The study was carried out on 2 groups of mongrel dogs. One group was subjected to left single-lung allotransplantation and the other to autotransplantation. Endothelin-1 levels in the bronchoalveolar lavage samples from the lung allografts were significantly increased at 1 (0.70 +/- 0.18 pg/ml) and 4 (1.84 +/- 0.65 pg/ml) hr after transplantation compared with the preoperative value (0.14 +/- 0.05 pg/ml), and declined at 24 (0.85 +/- 0.84 pg/ml) hr after transplantation. Similarly, plasma endothelin-1 levels in the allografts were significantly increased at 1 (2.0 +/- 0.80 pg/ml) and 4 (2.0 +/- 0.71 pg/ml) hr after transplant when compared with preoperative levels (0.54 +/- 0.09 pg/ml). Plasma endothelin-1 levels, however, remained significantly high after 24 hr (1.4 +/- 0.4 pg/ml; P < 0.007) and decreased after 1 week after transplant (0.89 +/- 0.32 pg/ml). On the other hand, endothelin-1 levels in bronchoalveolar lavage from the autograft group remained relatively unchanged; however, plasma levels showed a significant increase at 4 hr (6.6 +/- 1.8 pg/ml) after transplantation compared with preoperative levels (2.8 +/- 0.38 pg/ml). Elevation of endothelin-1 levels early after lung transplantation may play an important role in early high pulmonary vascular resistance and temporary graft dysfunction.
A period of cold and warm ischemia is obligatory when performing lung transplantation. Subtle ischemia-reperfusion injury induced in the course of transplantation can pass undetected or cause a short phase of reversible lung dysfunction. We hypothesized that ischemia-reperfusion injury may result in the local release of cytokines that have the capability to mediate acute lung injury early following transplantation. To test this hypothesis, 10 mongrel dogs were subjected to left lung allotransplantation. As performed in the clinical setting, donor lungs were preserved with Eurocollins solution and stored at 4 degrees C for 4 hr, which was followed by 1 hr of warm ischemia. Recipients received standard immunosuppression of cyclosporine, azathioprine, and low dose steroids. Bronchoalveolar lavage (BAL) and open lung biopsies were performed before operation and at approximately 1 hr, 4 hr, 24 hr, and 1 week after transplantation. A significant increase in BAL IL-2 levels was observed 4 hr after surgery (0 hr: 349 +/- 138 pg/ml; 4 hr: 757 +/- 284 pg/ml) (mean +/- SEM) (P < 0.05) which subsequently decreased 24 hr (320 +/- 168 pg/ml) after transplantation. BAL TNF-alpha levels were significantly increased 1 hr after transplantation (P < 0.05) (0 hr: 3.4 +/- 0.65 pg/ml; 1 hr: 13.3 +/- 8.0 pg/ml) returning to baseline after 24 hr (5.8 +/- 2.8 pg/ml). BAL IFN-gamma levels also significantly increased 1 and 4 hr after transplantation (0 hr: 7.2 +/- 2.1 pg/ml; 1 hr: 68.2 +/- 49.2 pg/ml; 4 hr: 301 +/- 131 pg/ml) (P < 0.05). This decreased back to baseline after 24 hr and 1 week (5.2 +/- 1.2 pg/ml and 9.7 +/- 7.9 pg/ml, respectively). There were no changes detected in plasma levels of cytokines. Histology showed evidence of grade 1-2 rejection after 1 week. We conclude that subjection of a lung allograft to standard periods of cold-warm ischemia will result in a temporary early elevation of IL-2, TNF-alpha, and IFN-gamma detectable only in the bronchoalveolar compartment. Such local increase in cytokines in the lung allograft may play an important role in the development of early allograft dysfunction.
OBJECTIVE: To determine whether the independently observed increase in the levels of cardiac enzymes in peripheral blood can be accounted for by elevations from postoperative shed-blood reinfusion in patients who have undergone cardiac or thoracic operations. DESIGN: Prospective, case-controlled study. SETTING: A cardiothoracic surgery unit at a university referral centre. PATIENTS: Thirty-four consecutive patients who underwent cardiac or thoracic surgery within a 3-week period. INTERVENTIONS: Coronary artery revascularization (23 patients), cardiac valve replacement or repair (4) and lung resection (7). MAIN OUTCOME MEASURES: Determination of levels of cardiac enzymes and isoenzymes in samples of peripheral and shed blood. Statistical comparison was by paired t-tests within groups and by unpaired t-tests between groups. RESULTS: Serum levels of creatine kinase, lactic dehydrogenase and aspartate aminotransferase were significantly (p < 0.001) elevated in samples of shed blood compared with peripheral blood in all groups. The elevations were found to be related to skeletal muscle injury and were not of cardiac origin. In the absence of myocardial infarction, cardiac isoenzyme levels were significantly (p < 0.001) elevated in the peripheral blood of cardiac surgery patients compared with that of thoracic surgery patients. CONCLUSION: Reinfusion of shed blood will result in elevated levels of cardiac enzymes in peripheral blood but will not increase the percentage of isoenzymes.
Double gloving may blunt perception of excessively warm instruments. We describe a case where this might have contributed to a cutaneous burn in a patient undergoing laparoscopic cholecystectomy. To test the role of two gloves in blunting temperature perception, we performed two experiments. In the first, 250 ml of water at 70 degrees C were placed in one glove or two gloves, and the rate of change of temperature after submersion in a bath at 18 degrees C was measured. The use of two gloves was associated with a marked decrease in rate of change in temperature (temperature at 5 min 37 +/- 2.3 degrees C [double gloves] versus 24 +/- 2.6 degrees C [single glove]; p < 0.001). In the second experiment, a thermometer covered with no gloves, one glove, or two gloves (group 5; n = 5) was submerged in a water bath at 90 degrees C. After 5 s, the temperature without gloves was 85.2 +/- 2.2 degrees C compared with 61.3 +/- 0.8 degrees C with one glove and 45.6 +/- 1.1 degree C with two gloves (p < 0.001). After 15 s, the temperature without gloves was 90.2 +/- 1.6 degrees C compared with 76.5 +/- 0.5 degrees C with one glove, and 64.4 +/- 0.8 degrees C with two gloves (p < 0.001). We conclude that the use of two gloves significantly decreases heat transmission, thus altering temperature perception.
Mechanical ventilatory support in the setting of unilateral lung disease offers unique problems in management. When the difference in airway resistance or lung compliance between the two lungs is exaggerated, conventional mechanical ventilation might lead to preferential ventilation with hyperexpansion of one lung and gradual collapse of the other. Differential ventilation has been advocated to avert this problem. We illustrate the use of this technique in the management of two patients with different underlying pathologic conditions.
We hypothesized that ischemic insult to the lung allograft may render it more susceptible to rejection. Left canine single-lung allografts were subjected to usual periods of cold and warm ischemia (4 hours and 1 hour, respectively). Bronchoalveolar lavage and open lung biopsies were performed at 0, 1, 4, and 24 hours and 1 week after transplantation. Bronchoalveolar lavage fluid was examined for cellular phenotypes, lymphocyte lectin-mediated cytotoxicity, and natural killer cell cytotoxicity. Open lung biopsy specimens were examined for severity of injury/rejection and MHC class II expression. Within 1 to 4 hours of reimplantation, we observed marked influx of polymorphonuclear leukocytes and lymphocytes and an increase in lectin-mediated cytotoxicity (25.6% +/- 14.8% and 50.6% +/- 20.1% versus 5.4% +/- 7.5% preoperatively; p < 0.05). In addition, natural killer cell cytotoxicity increased from 10.2% +/- 13.5% before transplantation to 20.5% +/- 8.6% 4 hours after transplantation (p < 0.03). By 24 hours MHC class II expression became evident and continued to increase while subtle histologic evidence of rejection appeared by 1 week. We conclude that ischemia-reperfusion injury can alter the local bronchopulmonary milieu, thus rendering it more susceptible to the development of rejection.
Lung transplantation has emerged as an acceptable option for the management of cystic fibrosis patients with endstage lung disease. Heart-lung transplantation and, more recently, double lung transplantation have been successfully performed in this group of patients. The choice of operation, so far, has been based on the surgeon's preference and experience as well as the cardiac function of the patient. Each of the procedures has advantages and disadvantages. This article reviews the current worldwide experience in lung transplantation for patients with cystic fibrosis and highlights the controversies involved in the selection of patients and procedure.
Donor availability remains the limiting factor to heart and lung transplantation. Donor selection criteria need to be continuously reassessed to expand the donor pool. The feasibility of organ donation from victims of carbon monoxide poisoning is unclear. We present a case of successful single lung transplantation from a carbon monoxide-poisoning victim.
Transplantation of a large lung allograft into a small chest could lead to atelectasis and hemodynamic instability. We developed a technique by which larger-sized lungs could be reduced to fit into smaller recipients. This entails multiple applications of a stapler device to progressively remove excessive lung tissue until the lung fits adequately into the recipient's chest cavity. An experimental animal model was used to test the applicability and safety of this technique. Because air leak from the resected margins was anticipated, we further examined the feasibility of reducing the latter by application of fibrin glue. Eight small mongrel dogs (20 to 25 kg) received left lung allotransplants from eight larger-sized dogs (35 to 40 kg) with the staple pneumoreduction technique. This group was further stratified to receive (group 1A; n = 4) or not receive application of fibrin sealant (group 1B; n = 4) to the stapled resection margins. Group 2 received lungs from similar-sized animals (20 to 25 kg; n = 4 each). Group 3 consisted of size-mismatched animals without pneumoreduction (n = 2). Recipient dogs were compared for facility of chest closure, gas exchange, and hemodynamic stability. The ability of the newly implanted lung to support respiratory function was also assessed by ligation of the opposite pulmonary artery at 4 hours. No difference was noted between groups 1 and 2 in terms of these variables. In sharp contrast, group 3 animals showed a rapid and profound drop in blood pressure after chest closure.(ABSTRACT TRUNCATED AT 250 WORDS)