Per Örtenwall

Endothelial cell seeding reduces thrombogenicity of Dacron grafts in humans

Vascular prostheses in humans do not endothelialize spontaneously. In the present study we explored the feasibility of seeding autologous endothelial cells into prostheses implanted in patients undergoing reconstruction of the infrarenal aorta. In 22 patients one limb of an aortic Dacron bifurcation prosthesis was seeded with autologous endothelial cells harvested from the distal portion of the saphenous vein. The other limb was sham-seeded with culture medium only. The effect of seeding was studied by use of indium 111 radiolabeled platelets and external gamma camera scanning at 1, 4, and 12 months after surgery. No complications ascribable to the seeding procedure were seen. During the first year after surgery a gradual decrease in platelet accumulation occurred over the whole vascular prosthesis. At all time points studied the seeded graft limbs exhibited significantly less deposition of radiolabeled platelets than did control limbs. The observed difference in platelet accumulation on autologous endothelial seeding-treated graft segments merits further investigation of this technique in humans.

Reduction in deposition of indium 111-labeled platelets after autologous endothelial cell seeding of Dacron aortic bifurcation grafts in humans: a preliminary report.

Autologous endothelial seeding (AES) of vascular prostheses in dogs increases thrombus-free surface and improves prosthetic prostacyclin production, patency, and the ability to withstand hematogenous challenge with bacteria. No such information is available in human subjects. In the present study one limb of an aortic Dacron bifurcation prosthesis was seeded with autologous endothelial cells (ECs) harvested from the distal portion of the saphenous vein by enzymatic treatment. The deposition of indium 111-labeled platelets on the vascular prostheses was studied 1 and 4 months after operation. In seven of nine patients seeding resulted in decreased accumulation of radiolabeled platelets compared with sham-seeded control limbs (p less than 0.04), when studied 1 month after surgery. A decrease in platelet accumulation occurred over the whole prosthesis between 1 and 4 months, and no significant difference was noted at 4 months between seeded and nonseeded graft limbs. Although the seeding density was very low (440 ECs/cm2), the observed difference in platelet accumulation for AES-treated graft limbs in the early postoperative course merits further investigation of this technique in human beings.

Reduced platelet deposition on seeded versus unseeded segments of expanded polytetrafluoroethylene grafts: Clinical observations after a 6-month follow-up * ** ***

The concept of autologous endothelial cell seeding has proved successful in animal models with respect to decrease of graft thrombogenicity and increase in patency. In the present study, application of this method in humans was explored. In 23 patients, random halves of expanded polytetrafluoroethylene grafts, used for lower limb arterial reconstructions, were seeded with endothelial cells at a seeding density of 3500 cells/cm2. These cells were derived from the saphenous vein by enzymatic harvesting. The other half was sham seeded with culture medium. Graft thrombogenicity was estimated by measuring platelet deposition on graft surface 1 and 6 months after surgery, with indium 111-labeled platelets and external gamma-camera imaging. Seeded graft segments accumulated significantly (p less than 0.03) fewer platelets at all imaging times. It is concluded that seeding of expanded polytetrafluoroethylene vascular grafts in humans reduces graft surface thrombogenicity. The clinical implications of this remain to be demonstrated.

Nomenclature, Classification, and Significance of Traumatic Extrapleural Hematoma

BACKGROUND Extrapleural hematoma has been found mostly in single case reports as diagnoses with different names. Although huge extrapleural hematoma can cause ventilatory and circulatory disturbances and even death, it has received almost no attention in the literature. Certain basic and modern facts need to be clarified regarding the definition, classification, and significance of extrapleural hematoma in the practice of chest trauma. METHODS A 10-year retrospective study was undertaken to analyze the incidence, diagnosis, management, morbidity, and mortality of patients with chest trauma and a documented extrapleural hematoma. RESULTS The incidence of traumatic extrapleural hematoma was 34 of 477, 7.1%. The incidence of thoracic lesions was 86 of 34 = 2.5 lesions per patient, whereas the incidence of extrathoracic lesions was 30 of 34 = 0.9 lesions per patient. Associated rib fractures were found in 30 of 34, 88.2%. More than half of the patients had an associated hemothorax. A thoracotomy was used successfully to remove a huge hematoma in one patient. CONCLUSION Extrapleural hematoma has been found to be more common than previously reported. Nomenclature and classification are suggested. One of the common injuries to the chest, particularly rib fracture, hemothorax, lung contusion, or pneumothorax might provide the surgeon with a reliable clinical clue that the patient is at inordinate risk to have associated extrapleural hematoma. A formal or mini-thoracotomy is the recommended procedure in cases of huge hematomas.

Performance Indicators for Major Incident Medical Management – A Possible Tool for Quality Control?

Objective: The objective was to determine the outcome when applying a set of proposed performance indicators on previously published reports from major incidents. Methods: A set of 20 different performance indicators were proposed. These indicators were applied to 13 reports from major incidents issued by the KAMEDO organization. Results: The most frequently reported problems were command and control at the scene (11/13) followed by communication and command and control at the strategic level. In 25% of the published reports there was enough information available to apply the performance indicators, and in these the goal and/or objective was met in 67%. Conclusion: Performance indicators for the medical management of major incidents and disaster can to a limited extent be applicable to retrospective studies. Performance indicators might be a tool for evaluating the medical response if reports are made with a different template. Further studies are needed in order to validate which indicators to use.

Cardiac injuries: a ten‐year experience

OBJECTIVE To present our experience of cardiac injuries treated at one Swedish emergency department in the 10 years 1988-97. DESIGN Retrospective study. SETTING Teaching hospital. SUBJECTS 11 patients (9 men and 2 women, mean age 33 years, range 19-54); in 7 they were penetrating injuries and in 4 blunt. MAIN OUTCOME MEASURES Morbidity and mortality. RESULTS The mechanisms of injury were stab wound (n = 7), and car crash, fall, boat crash, and abuse (n = 1 each); drug or alcohol misuse played a part in all those with penetrating injuries. The penetrating wounds involved the left ventricle (n = 3), the right ventricle (n = 2), and the pericardium (n = 2). All 5 patients with ventricular wounds presented with cardiac tamponade, in 1 of whom it was fatal (he bled to death during emergency thoracotomy). The main complications were anoxic brain damage and postpericardiotomy syndrome (1 each). There was no case of myocardial concussion. CONCLUSION Our data reflect the Swedish experience of heart trauma: there are few cases, alcohol and drug misuse is the principal risk factor, and there were no gunshot wounds.

Cardiovascular Injuries associated with Sternal Fractures

OBJECTIVE To find out if the presence of a sternal fracture indicates cardiac and aortic injuries and to clarify the difference between a retrosternal haematoma and widened mediastinum. DESIGN Retrospective study. SETTING Teaching hospital, Sweden. SUBJECTS 418 patients with blunt chest trauma of whom 29 had a fractured sternum (11 with retrosternal haematoma and 18 without) and 389 did not (7 with widened mediastinum and 382 without). MAIN OUTCOME MEASURES Definitions, risk factors, morbidity, and mortality. RESULTS Retrosternal haematomas were found adjacent to many fractures and ranged in size from a few mm to 2 cm. They were more common in fractures of the body of sternum. There was no significant difference in the number of associated lesions between patients with sternal fractures with or without a retrosternal haematoma. Conversely, patients with a widened mediastinum had a higher injury severity score, longer hospital stay (p < 0.0001), and more associated lesions (p < 0.05) than those with retrosternal haematomas. Six patients still had pain 1 month after injury of whom two had injury-related long-term disability because of pain. No serious cardiac or aortic injuries were detected in this series. The early mortality in our study was 2/29 in patients with sternal fractures and 1/7 in patients with widened mediastinum. CONCLUSIONS Sternal fractures are more common than previously reported. An aggressive approach including early operative reduction is recommended even for a stable fracture to reduce the overhelming pain. Sternal fracture with or without retrosternal heamatoma is not a reliable indicator of cardiac and aortic injuries, while mediastinal widening is still a fairly reliable clue that should indicate further investigation.

Outcome of lung trauma.

OBJECTIVE To find out whether we could manage critical pulmonary haemorrhages in penetrating injuries, and to report our experience with blunt trauma of the lung. DESIGN Retrospective study. SETTING Teaching hospital, Sweden. SUBJECTS 81 patients who presented with pulmonary injuries during the period January 1988-December 1997; 6 were penetrating and 75 blunt. RESULTS There was only one patient with an isolated lung contusion. The remaining was divided into 2 groups: those with pulmonary contusion and thoracic lesions (n = 32), and those with pulmonary contusion and extrathoracic lesions (n = 42). Four patients in the penetrating group were shocked and required urgent operations; emergency room thoracotomy (n = 1), urgent thoracotomy (n = 2), and urgent thoracoabdominal exploration (n = 1) were done successfully. We correlated grade of lung injury [American Association for the Surgery of Trauma-Abbreviated Injury Scale (AIS)] with mortality. All patients with penetrating injuries survived without serious consequences. There were a mean (SD), of 6 (2) injuries/patient in those with extrathoracic injuries compared with 3 (1) injuries/patient in the group with thoracic lesions (p < 0.001). The corresponding hospital mortality was 6/42 (19%) mainly as a result of the central nervous system lesions (4/6) compared with 0/32. The mean (SD) Injury Severity Score (ISS) was 9.3 (4.8) in patients with thoracic lesions compared with 24.1 (14.7) in patients with extrathoracic lesions (p < 0.0001), and 14.9 (9.5) in all survivors compared with 49.9 (13.6) among those who died (p < 0.0001). CONCLUSIONS An excellent outcome can be achieved managing penetrating injuries of the lung by an aggressive approach and urgent surgical intervention even when emergency room thoracotomy is essential. Pulmonary contusion is considered to be a relatively benign lesion that does not add to the morbidity or mortality in patients with blunt chest trauma. These data may help to decrease the obsession with pulmonary contusion in patients with chest trauma, with or without extrathoracic lesions, and avoid many unnecessary computed tomograms of the chest.

Performance indicators for prehospital command and control in training of medical first responders

The objective of this study was to determine if a set of performance indicators could indicate what part of medical command and control needs to be improved in a training concept designed for medical officers at major incidents. A set of 11 different performance indicators previously proposed was used as a template when examining ambulance staff in medical command and control. The results were graded 0 to 2 where 0 = not acceptable, 1 = partially correct and 2 = correct. A total of 46 examinations comprising more than 200 students was included. Performing a correct second report (score 1.15), the ability to establish general guidelines for medical response (score 1.20), setting level of medical ambition (score 1.24) and informing media (score 1.33) had significantly lower scores than the other performance indicators. Performance indicators for medical management in a major incident can be used in a training setting for identifying areas that need improvement.

Thoracic vascular injuries: a major problem in trauma.

Objective - We present a review of our experience in the management of thoracic vascular injuries during the past 10 years in one of Swedens busiest emergency departments, with morbidity and mortality as the main outcome measures. Design - Of eight patients who sustained chest trauma with thoracic vascular injuries, six presented with shock. Angiography was the gold standard in diagnosing aortic and subclavian injuries. Results - Lesions of the inferior vena cava, left internal mammary artery, and intercostal vessels were detected only at surgery. Two patients died of exsanguination. Managing thoracic vascular injuries is still difficult and challenging for thoracic and trauma surgeons. Conclusion - Early thoracotomy is important for salvage of patients with chest-wall vascular injury. Despite our limited experience, which is characteristic for Scandinavian and European countries, our results were satisfactory.OBJECTIVE We present a review of our experience in the management of thoracic vascular injuries during the past 10 years in one of Swedens busiest emergency departments, with morbidity and mortality as the main outcome measures. DESIGN Of eight patients who sustained chest trauma with thoracic vascular injuries, six presented with shock. Angiography was the gold standard in diagnosing aortic and subclavian injuries. RESULTS Lesions of the inferior vena cava, left internal mammary artery, and intercostal vessels were detected only at surgery. Two patients died of exsanguination. Managing thoracic vascular injuries is still difficult and challenging for thoracic and trauma surgeons. CONCLUSION Early thoracotomy is important for salvage of patients with chest-wall vascular injury. Despite our limited experience, which is characteristic for Scandinavian and European countries, our results were satisfactory.