Emergent Endoluminal Repair of Delayed Abdominal Aortic Rupture after Blunt Trauma

Purpose:

To report the emergency repair of a traumatic abdominal aortic rupture using endoluminal techniques.

Methods and Results:

A 25-year-old female sustained multiple head, chest, and abdominal injuries in a motorcycle accident. Six days after emergency treatment (including splenectomy and repair of a superficial hepatic rupture and lacerations to the stomach, small bowel, and colon), she became hemodynamically unstable. A massive retroperitoneal hematoma had evolved from a distal aortic rupture. Owing to a hostile abdomen and possibility of bacterial contamination, a self-expanding stent-graft was inserted transfemorally to repair the aortic injury. The patient recovered uneventfully and continues in good health with a patent endograft repair 2 years after treatment.

Conclusions:

This experience would support the efficacy of endograft implantation for emergent repair of trauma aortic injuries; however, proper facilities, an experienced interventional team, and an assortment of endografts and stents must be available.

[Fast track in thoracic surgery]

Patients undergoing thoracic surgery are threatened by pulmonary complications such as pneumonia and atelectasis. Age, preoperative FEV(1), operative time and extent of resection are predictors for adverse outcome. Reported morbidity after lung resection is as high as 42% and mortality up to 7%. Fast track in thoracic surgery aims at reducing morbidity and mortality rates after lung resection by introducing specific measures into the pre-, intra- and postoperative periods. Basic fast track elements in thoracic surgery are smoking cessation, preoperative physiotherapy, micronutrient supplementation, high thoracic epidural anesthesia, fluid restriction, early mobilization and enteral feeding. The effectiveness of these individual measures has been proven of value in perioperative care, however, evidence on multimodal therapy regimens in thoracic surgery is limited. In particular it remains to be elucidated which patients should be fast tracked in order to improve outcomes.

Endovascular Treatment (EVT) of Acute Traumatic Lesions of the Descending Thoracic Aorta – 7 Years' Experience

OBJECTIVES

To present a single centers' 7-year experience in the endovascular treatment of acute traumatic lesions of the descending thoracic aorta (ATL of the DTA).

MATERIALS & METHODS

Between March 1999 and December 2006, 34 consecutive acute traumatic lesions of the descending aorta (23 men, mean age 44 years) were treated endovascularly. Stentgrafts used were TAG Excluder, Zenith TX2 and Talent. In 23 patients the Left Subclavian Artery (LSA) was covered. Mean procedural duration was 20 to 75 minutes.

RESULTS

Exclusion of the rupture site was achieved in all cases with no conversion to open surgery. Overall 30-day mortality was 8.8%. Two patients died on post operative day (pod) 1 and one on pod 22 from cranial injuries. No death or neurological deficit related to the endovascular treatment was reported. Four type I endoleaks required treatment either by balloon reexpansion (n=2) or by additional stentgraft implantation (n=2). In two patients the stentgraft collapsed totally several days postoperatively. Two patients required secondary surgical procedures (iliac access complication and revascularisation of the left subclavian artery n=1). The average follow-up was 43.8 months (1-93 months). No stentgraft related abnormality has been subsequently documented.

CONCLUSIONS

The endovascular treatment of ATL of the DTA may offer the best means of therapy in a polytrauma patient.

[The vascular surgeon's role in intensive care]

The role of vascular surgeons in the intensive care unit includes two major tasks: (1) consultant activity in complications of different operative specialties, for instance postoperative venous thrombosis after Wertheim's operation, mesenteric superior artery embolus, or arterial injury after total prosthetic replacement of the hip, (2) postoperative care following vascular surgery in order to identify and treat specific complications such as limb ischemia after reconstructive surgery, compartment monitoring after reperfusion injury of the aorta or extremities, carotis monitoring after postoperative apoplexy, and subsumed identification and treatment of ischemic and postischemic states in organs and tissues. Keeping vascular reconstructive options open is particularly important for polytrauma patients with blunt or open vascular injuries beginning from the thoracic aorta ending with subtotal amputation of the lower leg. Vascular surgeons in an intensive care setting play the central role in setting diagnostic course and therapy measures, while organ substitute therapy is within the administrative jurisdiction of the intensivist. Considering the complexity of morbidity in vascular patients, consultation by the intensivist, cardiologist, and neurologist is warranted.

[Thorax injuries]

Thorax injuries may be divided etiologically into blunt and penetrating types, depending on the nature of the insult. In European practice, the former predominates by far, and in only about 5% of cases thoracotomy provides the necessary thorax drainage. Morbidity in this type of injury typically involves concomitant lung contusion, sometimes with fatal acute respiratory distress syndrome. In these cases, special ventilation forms, optimal reduction of pain, and organ replacement are the decisive therapeutic methods. In contrast, about 80% of penetrating trauma to the thorax require prompt transpleural or trans-sternal surgery, depending on the type of injury. Emergency first aid must follow the principle of "scoop and run". Each minute elapsed until emergent thoracotomy can be decisive to survival in these cases, and the fastest possible transport from the place of injury takes priority over time-consuming stabilization.

Stentgrafting of the thoracic aorta-complications

Endovascular therapy (EVT) of thoracic aortic pathologies meanwhile is an established procedure with favourable midterm results in high risk patients. Different stent fabrications are available with defined flexibility, radial attachment force, metallic stent components and membrane porosities. Recent approval of the TAG Excluder (Gore) by the Food and Drug Administration (FDA) was an important step. Endoleaks, paraplegia, stroke and retrograde dissections are the main specific complications. Type I endoleak incidence rates are related to morphological case complexity; primary frequency rates of 0-20% are reported in the literature with 0-5% secondary incidence. Creating an appropriate proximal neck -- if necessary by supra-aortic branch remodelling -- and deliberate left subclavian artery overstenting is the key mechanism to avoid proximal endoleaks. Paraplegia rates are reportedly low with EVT in the range of 0-5%. Risk situations are: cases of rupture with compromised blood pressure, cases with a history of abdominal aortic aneurysm (AAA) exclusion, cases who require total overstenting of the descending thoracic aorta. The role of cerebrospinal fluid (CSF) drainage in EVT is not defined. Stroke as consequence of embolizing material from central endoaortic manipulations is almost in the same range as paraplegia, when morphologies in the distal arch are attacked. Retrograde dissection is reported not only after treatment of type B dissection but also after aneurysms. Rigid bare springs and ballooning in cases of type B dissection seem to be involved. In recent reports mortality in elective cases varies between 1.5% and 6.5%. All these data are promising but the proof of longterm durability is still lacking. Further development will show whether or not these preliminary data will translate into longterm success.

[Interdiscplinarity in thorax operations-from the viewpoint of the surgeon]

Occasionally, thoracic interventions may require interdisciplinary teamwork with plastic surgery, heart and vascular surgery, or neurosurgery. Thoracic wall defects following excision of primary wall tumors or recurrent, ulcerating tumors of the breast may require full-thickness myocutaneous flaps, which can best be done with the help of plastic surgeons. In case of infiltration of the heart or thoracic aorta, the en bloc principle of T4 lung tumors occasionally requires the help of heart surgeons, for open atrial resection using the heart-lung machine, or vascular surgeons for aortic graft interposition. Paravertebral dumbbell tumors occasionally may infiltrate to the intraspinal space and therefore need removal by neurosurgeons. When and why other specialists are required for an interdisciplinary approach to diseases of the chest has not been clearly defined. Therefore it is wise to gain informed consent from the patient about the roles of different specialists in interdisciplinary treatment for his disease.

Endovascular exclusion of thoracic aortic aneurysms: mid-term results of elective treatment and in contained rupture

PURPOSE

The purpose is to present results of endovascular exclusion (stent-graft treatment) of aneurysms of the descending thoracic aorta both in elective cases and in emergencies.

METHODS

Indications for stent-graft treatment were dependent on multislice angio-CT evaluation revealing a proximal neck of at least 10 mm between the left common carotid artery and the onset of aneurysm. All stent grafts were inserted in the operating room; 43 transfemoral, 2 transiliac. The stent grafts used were Corvita, Stenford, Vanguard, AneuRx, Talent, and Excluder. Deployment was achieved under fluoroscopic control, endoleaks were checked for with D S A on the operating table and postoperatively by angio-CT. Long-term follow-up consisted of evaluation with angio-CT after 6 and 12 months, and from there on once a year and with plain chest X-rays. Follow-up was achieved in all patients.

RESULTS

Mean follow-up is 21 months (1-66); 30-day mortality is 3/45, no permanent neurologic deficit. Thirty patients were treated electively, 15 with contained rupture. Left subclavian artery overstenting proved to be necessary in 12 patients for proper proximal sealing of the aneurysm, type I endoleaks were observed in 10 patients, one early conversion, 7 proximal extension cuffs, one sealed spontaneously, one still at risk. Among patients where LSA had been overstented only one wanted a transposition, all others did well without left-hand ischemia or subclavian steal syndrome.

CONCLUSION

Endovascular treatment is less invasive and has reasonable mortality and morbidity but is limited to well-defined morphologies. Mid-term results are promising but it has to be observed whether these will translate into long-term durability.

Treatment of thoracoabdominal aortic aneurysms with a combined endovascular and surgical approach

AIM

The conventional approach for the repair of thoracoabdominal aneurysms remains complex and demanding and is associated with substantial morbidity and mortality. Moreover, in cases of reoperation the impact can be dramatic either in survival or in quality of life of the patients, albeit the use of adjuncts. A combined endovascular and surgical approach with retrograde perfusion of visceral and renal vessels has been realized in order to minimize intraoperative and postoperative complications.

METHODS

Within an experience of 231 aortic stent-grafts between 1995-2000, 4 of the patients with thoracoabdominal aneurysms were treated with a combined endovascular and surgical approach. Three procedures were electively conducted and 1 on emergency basis. Two women, 59 and 68 years old, and 2 men, 68 and 73 years old (maximum aneurysm's diameter was 10, 6, 8 and 9 cm, respectively) were operated with the combined method (the first 2 patients had a previous open repair of a thoracoabdominal aneurysm). The surgical approach was executed in all patients without thoracotomy or re-do retroperitoneal exposure. Revascularization of renal, superior mesenteric (and celiac in 2 cases) arteries was accomplished via transperitoneal bypass grafting. Aneurysmal exclusion was performed by stent-graft deployment.

RESULTS

The entire procedure was technically successful in all patients. The 1(st) patient was discharged 6 weeks after the operation, while the postoperative studies revealed the patency of the vessels and no evidence of leak or secondary rupture of the aneurysm; the patient died 3 months after the repair, due to rupture of an aneurysm of the ascending aorta. In the 2(nd) patient, 30 months after the operation, spiral-CT scanning revealed distinct shrinkage of the aneurysm, no graft migration or endoleak and patency of all revascularized vessels. The 3(rd) patient died on the 6th postoperative day due to multiorgan failure after having developed ischemic-related pancreatitis, albeit the successful combined repair. The 4(th) patient followed an uneventful course. No patient experienced any temporary or permanent neurological deficit.

CONCLUSION

The combined endovascular and surgical approach is feasible, without cross-clamping of the aorta and with minimized ischemia time for renal and visceral arteries, and seems the appropriate strategy for high risk and previously operated, with a thoracoabdominal trans-diaphragmatic approach, patients.

Endovascular treatment in diseases of the descending thoracic aorta: 6-year results of a single center

OBJECTIVE

The purpose of this study was to evaluate endovascular treatment in diseases of the descending thoracic aorta.

MATERIAL AND METHODS

This study was designed as a single center's (university hospital) experience. Over a 6-year period (1995 to 2001), thoracic endografts were placed in 74 patients with a diseased descending thoracic aorta who were at high risk for conventional open surgical repair: 34 had atherosclerotic aneurysms, six had posttraumatic aneurysms, 14 had type B dissection with aneurysmal dilatation of the false lumen, 12 had isthmic transections from blunt trauma, five had thoracoabdominal aneurysms (treated with a combined procedure), two had aortic coarctation, and one had an aortobronchial fistula. Twenty-six procedures (35.1%) were conducted as emergencies, and 48 (64.9%) were elective. The feasibility of endovascular treatment and sizing of stent grafts were determined with preoperative spiral computed tomography and intraoperative angiography.

RESULTS

Endovascular operations were completed successfully in all 74 patients; postprocedural conversion to open repair was necessary in three cases. The overall 30-day mortality rate was 9.5% (seven deaths). Temporary neurologic deficits developed in two patients; not one patient had permanent paraplegia. The primary endoleak rate was 20.3% (15 patients). The mean follow-up period was 22 months (range, 3 to 72 months). Five deaths occurred in the follow-up period, and three patients needed secondary conversion to open repair 2, 3, and 14 months after initial endografting.

CONCLUSION

Endoluminal treatment in diseases of the thoracic descending aorta is feasible and may offer results as good as the open method.

[Endoluminal stent-assisted management of acute traumatic aortic rupture]

INTRODUCTION

Open repair of traumatic descending aortic rupture in trauma patients is associated with a mortality rate of 15-20% and a risk of paraplegia of 5-10%. Stent grafts may decrease the morbidity and mortality of these procedures by reducing blood loss and aortic occlusion time.

MATERIAL AND METHODS

Within an experience of 52 thoracic stent grafts between 1995 and 2000, eight men with acute traumatic descending aortic rupture were conducted as emergencies without delay. All patients had severe coinjuries and presented with acute onset of mediastinal hematoma due to periaortic bleeding. Successful stent deployment was performed in all eight patients, seven of them required one single stent and one required two stents; within the aortic arch all stents covered the origin of the left subclavian artery.

RESULTS

All acute aortic ruptures were sealed successfully. One death occurred in hospital from multiorgan failure. There was no conversion to open repair. Not one patient's condition resulted in temporary or permanent paraplegia. One endoleak required treatment by overstenting. Two patients required secondary surgical procedures (iliac access complication and revascularisation of left subclavian artery). Mean follow-up was 11 months (1-21 months). Mid-term freedom from endoleak was monitored in all patients.

CONCLUSION

The treatment of acute traumatic descending aortic rupture with an endovascular approach is feasible and safe and may offer the best means of therapy. The mortality rate and risk of paraplegia are low compared with the risks associated with open operations. Continued surveillance is essential.

Endovascular repair of aortic rupture due to trauma and aneurysm

OBJECTIVES

to report a single centre experience with endovascular repair of the ruptured descending thoracic and abdominal aorta.

DESIGN

prospective non-randomised study in a university hospital.

MATERIAL AND METHODS

between 1995 and 2000, endovascular treatment was utilised for 231 aortic repairs; in 37 cases (16%) endografting was conducted on an emergency basis for 21 ruptured infrarenal aortic aneurysms, 15 ruptured descending thoracic aortic lesions, and 1 ruptured thoracoabdominal aortic aneurysm. The feasibility of endovascular treatment and the prostheses' size were determined, based on preoperative spiral CT and intraoperative angiography, both obtained in each patient.

RESULTS

endografting was successfully completed in 35 patients (95%). Primary conversion to open repair was necessary in 2 patients (5%). Postoperative 30-day mortality rate was 11% (4 deaths). No patient developed postoperative temporary or permanent paraplegia. In 2 patients (5%) primary endoleaks required overstenting and in 6 patients (16%) secondary surgical interventions were required. Mean follow-up was 19 months (1-70 months); three deaths occurred within three months postoperatively (1-year survival rate 81+/-6%). In one case, secondary conversion to open repair was necessary 14 months postoperatively.

CONCLUSION

the feasibility of endoluminal repair of the ruptured aorta has been demonstrated. Endoluminal treatment may reduce morbidity and mortality, and may in time become the procedure of choice in certain centres. However, further follow-up is required to determine the long-term efficacy.

[Repeat rupture of covered rupture of non-anastomotic false aneurysm after femoropopliteal bypass]

For arterial reconstructions veins or alloplastic vascular prostheses are used. Nonanastomotic pseudoaneurysms of vascular protheses are a rare event. Breaks of the suture material, structural defects of the transplant fabric or degenerative modifications in the recipient vessel can cause nonanastomotic or anastomotic pseudoaneurysms. Such pseudoaneurysms are known from early clinical application of ePTFE grafts. In the case presented a nonanastomotic rupture of a ePTFE graft is described with partial repair of the rupture site by fibroblasts and connective tissue, which prevented bleeding.

Leakages after endovascular repair of aortic aneurysms: classification based on findings at CT, angiography, and radiography

PURPOSE

To ascertain whether the configuration and location of leakages identified at computed tomography (CT) could provide evidence of their angiographically and fluoroscopically confirmed causes.

MATERIALS AND METHODS

Fifty patients aged 26-79 years underwent endovascular repair of traumatic (n = 4) or arteriosclerotic (n = 46) aortic aneurysms (four thoracic, 46 infrarenal). Radiographic examinations in three planes and helical CT were performed 1 week after implantation and every 3 months thereafter. Angiography was performed when there was evidence of a leakage at CT.

RESULTS

CT demonstrated evidence of leakages in 13 patients. Broad-based leakages immediately adjacent to the prosthesis were termed "perigraft leakages." If the area most affected by the leakage lay along the border of the aneurysm, then retrograde leakages were apparent at angiography. If the leakage was ventral to the prosthesis, then its source was the inferior mesenteric artery; if it was dorsolateral, then it was supplied by either the lumbar arteries or the median sacral artery through the hypogastric artery. One circumferential leakage could not be evaluated adequately at CT or angiography. Radiography depicted a rupture of the stent mesh in the middle of the prosthesis. Selective angiography demonstrated all types of leakages and permitted CT classification.

CONCLUSION

The cause of a leakage can be determined with CT on the basis of its configuration and location in the majority of cases.

Endovascular repair of aortic aneurysms: treatment of complications

PURPOSE

To evaluate the use of interventional procedures for treating complications following endovascular repair of aortic aneurysms.

METHODS

Fifty-five patients (49 men; mean age 67.5 years) underwent endoluminal stent-graft repair of traumatic (n = 4) or arteriosclerotic (n = 51) aortic aneurysms in the thoracic (n = 3) or infrarenal (n = 52) aorta. Follow-up of therapeutic success included periodic clinical examination, angiography, and spiral computed tomography.

RESULTS

Discounting the 25 (45%) cases of postimplantation syndrome that did not require treatment, there were 22 complications observed in 20 (36%) patients over a mean 10-month follow-up (range 1 to 27). There were 2 transrenal endograft maldeployments, 1 case of twisted graft limbs, 2 access site problems (1 patient), 12 endoleaks (11 patients), 1 late graft limb thrombosis, 1 symptomatic internal iliac artery occlusion, 2 myocardial infarctions, and 1 transient psychosis. Seven (13%) patients did not undergo specific therapy, while 4 (7%) required operation (2 crossover bypass grafts, 1 suture revision, and 1 graft replacement). Among 9 (16%) patients treated with interventional techniques, 7 underwent percutaneous coil embolization for 8 endoleaks (7 successfully resolved). One late stent-graft disconnection required an additional stent-graft, and 1 of the 2 malpositioned endografts was repositioned. All patients remain alive with no increase in the diameter of the aneurysm in any patient.

CONCLUSIONS

Technical problems resulting from the endovascular repair of aortic aneurysms often respond to interventional treatment.

Endoluminal grafting of infrarenal aortic aneurysms

BACKGROUND

The department policy regarding therapy fo infrarenal aortic aneurysms is reviewed, based on the treatment results of a 12-months period.

METHODS

From October 1996 to August 1997, 60 patients with infrarenal aortic aneurysms were admitted to our department. Of these 31 (52%) were found to be anatomically or pathomorphologically suitable for endovascular treatment, based on the premises that: 1. Whenever the anatomy is suitable and confirmed with CT or angiography, repair is by means of stent placement. 2. In emergencies and in cases where the anatomical relationships are unfavourable, patients undergo conventional open surgery.

RESULTS

In all 31 patients treated endovascularly, stent placement was technically successful. Procedure-associated mortality was zero. The following stenting complications occurred: seven endoleaks, one thrombotic iliac occlusion, one femoral arterial dissection, two puncture-related inguinal hematomas. Elective open surgery was performed in the other 29 patients. One of these died from the effects of renal failure.

CONCLUSIONS

This comparison shows that endovascular treatment of infrarenal aortic aneuryms is possible in a large proportion of patients and is not associated with an unfavourable rate of complications. Endovascular treatment can significantly reduce patients' postoperative hospitalization (three days) and time spent in intensive care.

[Value of stent-assisted aneurysm treatment]

The aim of this study was to compare the outcome of consecutive patients with abdominal aortic aneurysms treated by open operation and endoluminal procedure. Between October 1996 and April 1998 consecutive patients with abdominal aortic aneurysms underwent surgical repair. Of these, 50 patients had conventional open repair, and 48 patients were treated endoluminally. Follow-up was made by clinical examination in the operation group; the stent group was controlled by spiral CT and angiography 1, 3, 6, and 12 months after operation. No significant difference was found in the perioperative mortality rate between the open repair group and the stent group. This study suggests that the endovascular procedure is safe and results in a shorter length of hospital stay and a shorter length of intensive care unit stay. As there are no long-term results, the endoluminal method requires a careful follow-up.

Comparison of virtual and fiberoptic bronchoscopy

Preoperative diagnostic procedures in the treatment of non-small-cell lung carcinoma (NSCLC) include fiberbronchoscopy (FBS) and CT scanning of the thorax and abdomen. The introduction of double-detector helical computed tomography has led to improved image resolution which allows three-dimensional reconstruction of the bronchial tree. A special computer simulation provides a virtual endoscopic view into the inner surface of the bronchial system. In order to determine whether the so-called virtual bronchoscopy (VBS) accurately reflects the anatomic situation of the bronchial tree, neoplastic lesion, and postoperative control of sleeve resections, we performed a virtual bronchoscopy in 24 patients with NSCLC and in 6 patients following sleeve resections and compared the results with the findings of fiberoptic bronchoscopy. An anatomic computer simulation of the bronchial tree was created in 100% of the investigated patients. Central tumor stenosis or occlusion was visualized by VBS as well as by FBS. In peripheral tumorous lesions VBS revealed the correct diagnosis in only 75%. VBS, however, enables viewing beyond the stenosis. FBS remains the gold standard in the endoscopic diagnostic procedures, showing not only airway patency but also mucosal changes in the vicinity of the tumorous lesion. VBS, however, gives further information about the poststenotic area in occlusive main bronchus stenosis. Furthermore, adequate control investigation of airway patency in patients following sleeve resections or stent implantation can be performed by VBS.

Vasopressor hormone response following mesenteric traction during major abdominal surgery

BACKGROUND

We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI2) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia.

METHODS

In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGF1 alpha (stabile metabolite of PGI2), TXB2 (stabile metabolite of thromboxane A2) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection.

RESULTS

Following MT, arterial hypotension occurred along with a substantial PGI2 release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF1 alpha (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P = 0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB2 (164 (87) vs. 58 (1) ng/L, P = 0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P = 0.001), AVP (41 +/- (18) vs. 12 (7) ng/L, P = 0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients.

CONCLUSION

Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI2 release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A2, presumably contributing to hemodynamic stability within 30 min after MT.

Diagnostic value of spiral-CT angiography in comparison with digital subtraction angiography before and after peripheral vascular intervention

To evaluate spiral-computed tomography (CT) angiography in primary diagnosis and/or in noninvasive follow-up after vascular intervention, we compared spiral-CT angiography and conventional angiography before and after vascular intervention. Helical-CT examinations before and after percutaneous transluminal angioplasty (PTA) or stent implantation were performed in 10 patients (mean age 63 years) with symptomatic peripheral arteriosclerotic disease. Stenoses were located in the iliac, femoral, or popliteal artery. CT examinations were done with a spiral-CT in double detector technique (CT Twin, Elscint). The parameters were as follows: slice thickness: 5.5 mm, increment: 2.7 mm, pitch: 1.5, contrast medium: 150 mL, flow rate: 2.5 mL/second, delay: 30 seconds. For evaluation, transverse planes as well as maximum intensity projections and 3-D reconstructions were used. The possible scan length reached from the aortic bifurcation down to about 10 cm below the ankle trifurcation. Preinterventional digital subtraction angiography (DSA) was superior to CT angiography (CTA: 94%, maximum intensity projection [MIP] alone: 65%), although high-grade stenoses were detected by both methods. After intervention, a resolved stenosis and improved peripheral flow could be detected by helical-CT as well as by intraarterial angiography in every patient (100%). In the primary diagnosis of vascular changes, intraarterial DSA remains the method of choice. Nevertheless, spiral-CT angiography shows comparable results after percutaneous intervention and becomes a noninvasive alternative in the postinterventional follow-up.

[Paraganglioma of the carotid bifurcation. Diagnostic and therapeutic strategy]

The carotid body tumors are semimalignant tumors. According to our results, the best diagnostic procedure is a combination of Doppler color flow imaging ultrasound, computed tomography and selective angiography. In our opinion, the treatment of choice is radical resection of the tumor with the carotid bifurcation, especially to reduce recurrence of the tumor. Considering the problems in recurrent tumors, consequent monitoring of the patients is necessary.

Emergent endoluminal repair of delayed abdominal aortic rupture after blunt trauma

PURPOSE

To report the emergency repair of a traumatic abdominal aortic rupture using endoluminal techniques.

METHODS AND RESULTS

A 25-year-old female sustained multiple head, chest, and abdominal injuries in a motorcycle accident. Six days after emergency treatment (including splenectomy and repair of a superficial hepatic rupture and lacerations to the stomach, small bowel, and colon), she became hemodynamically unstable. A massive retroperitoneal hematoma had evolved from a distal aortic rupture. Owing to a hostile abdomen and possibility of bacterial contamination, a self-expanding stent-graft was inserted transfemorally to repair the aortic injury. The patient recovered uneventfully and continues in good health with a patent endograft repair 2 years after treatment.

CONCLUSIONS

This experience would support the efficacy of endograft implantation for emergent repair of trauma aortic injuries; however, proper facilities, an experienced interventional team, and an assortment of endografts and stents must be available.

Ibuprofen does not impair renal function in patients undergoing infrarenal aortic surgery with epidural anaesthesia

OBJECTIVE

To investigate the effect of preoperative ibuprofen administration on renal function during and after infrarenal aortic surgery under thoracolumbar epidural anaesthesia (EPA).

DESIGN

A prospective randomised, double-blinded clinical study.

SETTING

Operation room and intensive care unit in a university hospital.

PATIENTS

Twenty-six consecutive patients scheduled for elective infrarenal aortic surgery.

INTERVENTIONS

The patients were prospectively randomised to receive 400 mg ibuprofen intravenously (i.v.) or a placebo aliquot before surgery.

MEASUREMENTS AND RESULTS

We assessed renal function by calculating creatinine clearance, and fractional sodium excretion before surgery (baseline), 1 h after cross-clamping (intraoperative), 6 h after cross-clamping (postoperative) and 24 h after cross-clamping (on the 1 st postoperative day). At each point in time, we additionally registered haemodynamics and determined the plasma concentration of 6-keto-PGF1alpha (stable metabolite of prostacyclin, PGI2), bicyclic PGE2 (stable metabolite of PGE1 E2), active renin, aldosterone and vasopressin by radioimmunoassays. Throughout the observation period the renal function parameters mostly remained within the normal range without a significant difference between ibuprofen- and placebo-treated patients (creatinine clearance: baseline 41 +/- 3 vs 38 +/- 6, intraoperative 57 +/- 8 vs 64 +/- 11, postoperative 64 +/- 9 vs 56 +/- 9, first postoperative day 43 +/- 5 vs 47 +/- 6 ml x min x m(-2), means +/- SEM). The plasma levels of 6-keto-PGF1alpha (68 +/- 8 vs 380 +/- 71* ng x l(-1)), bicyclic PGE2 (57 +/- 5 vs 88 +/- 9* ng x l(-1)) and vasopressin (14 +/- 7 vs 45 +/- 10* ng x l(-1), p < 0.0125), however, were significantly higher during the intraoperative period in the placebo-treated patients.

CONCLUSION

The inhibition of endogenous prostaglandin release by ibuprofen does not substantially impair renal function during infrarenal aortic surgery under EPA.

Inferior pancreaticoduodenal artery aneurysm as a consequence of traumatic acute pancreatitis. A case report and review of the literature

Inferior pancreaticoduodenal artery (PDA) aneurysms are rare: To date, only 88 cases have been reported in the English literature. Although atherosclerosis represents the most common histological finding (60%), the pathogenetic mechanism consists usually of vessel erosion owing to acute or chronic pancreatitis. Most of these lesions are undetectable until symptoms of rupture occur. Rupture occurs typically in association with an episode of pancreatitis (60%) and caries a high mortality rate (50%), making diagnosis and early treatment essential. Angiography and computed tomography (CT) readily confirm the diagnosis. Ligation or resection of the aneurysm represents the definitive and radical therapy, but in an emergency, entails a high mortality rate (50%). Transcatheter embolization is a valid alternative to control bleeding (80%) in order to stabilize the patient; in some cases, it represents a definitive treatment. We present a case of an aneurysm that developed in a patient who had had posttraumatic acute pancreatitis. A surgical procedure with proximal and distal ligation of the aneurysm was performed successfully.

Histomorphological examination of endoluminal stent grafting in the descending aorta in a sheep model

Experiments were designed to examine the wound healing characteristics at the aorta-endograft interface. Thoracic aneurysms were induced in sheep and excluded by endovascular placement of a selfexpanding stent graft (Corvita Endovascular Graft). After a follow-up of 1, 4, or 12 weeks sheep were sacrificed and the corresponding segments of the aorta were subjected to histological examinations. Histomorphological evaluation of all groups underlined sufficient exclusion of lesions of the aortic wall by endovascular grafting. There was no evidence of proximal or distal leakage, graft dislocation or migration. The results appeared to be evidence that the endoluminal stent graft may be incorporated by the host aortic tissue.

[Cervical sympathetic paraganglioma]

A 24-year-old man presented with a long-standing history of Horner's complex and a slowly growing cervical mass. Duplex-sonography, angiography, and computed tomography revealed a hypervascularized tumor with well defined borders displacing the left carotid bifurcation medially. Operative and histological findings confirmed the preoperative diagnosis of cervical sympathetic paraganglioma.

Traumatic rupture of the descending thoracic aorta

Timing and tactics in the repair of the traumatic ruptured thoracic aorta are matter of controversy ever since. The unmeasurable risk of a consecutive rupture favours a primary repair, concomitant injuries, however, a delayed repair. In single injuries of the thoracic aorta the clamp/repair procedure within 24 hours generates acceptable results with an overall mortality of 4 to 8% and a risk of ischemic myelopathy of 8 to 10%. Delayed repair reduces these figures not at all. Extracorporal circulation produces rather worse results in contrast to clamp/repair procedures. In cases of severe concomitant injuries, e.g. brain damage, hemorrhage and open fractures a delayed repair after cardiopulmonary reconstitution is required. In cases with posttraumatic pulmonary insufficiency the risk of surgical procedure itself is much higher than the risk of a second rupture of the traumatized thoracic aorta. We demonstrate our tactics in the repair of traumatic rupture of the descending aorta displaying clinical operated 1992/93.

[Prophylactic indications in thoracic aortic aneurysm]

Prophylactic operations of aneurysms of the descending thoracic aorta have to take into consideration the expansion rate, probability of rupture and individual life expectancy of patients > 70 years of age as well as the individual risk of operation. Candidates for elective surgery are those with large aneurysms and low operative risk from low comorbidity who are expected to experience death from acute rupture unless operated on in a prophylactic way. Endoluminal stent grafts--though very attractive in this aortic segment--are still in statu nascendi and not recommended for general use.

Management of descending aortic dissection

The optimal timing of surgery with Stanford type B aortic dissection remains controversal. In acute-phase cases, surgical mortality is so high that medical treatment is preferable unless there are major complications. To guide the choice of medical versus surgical therapy we use survival analysis in patients with acute uncomplicated/complicated and chronic uncomplicated/complicated descending aortic dissection. Between 1992 and 1993 49 patients were diagnosed with Stanford type B aortic dissection. Emergent surgery was performed in 4 patients for rupture or impending rupture, elective surgery was done in 12 patients. The remaining 33 patients were treated medically. Our results support the continued use of medical management as the primary treatment for uncomplicated acute aortic dissection, with surgical therapy being reserved for those patients with complications such as rupture, expansion, continuing pain or ischemia of distal vascular beds.

[Percutaneous aspiration thromboembolectomy in the treatment of acute occlusion of the lower leg arteries]

Percutaneous aspiration thrombembolectomy (PAT) is a very suitable method for the recanalization of the popliteal and lower limb arteries after embolic occlusion. In thrombotic occlusion in patients with arteriosclerotic disease, PAT can easily be combined with other interventional procedures, yielding good results. With the use of PAT the dose of regionally effective fibrinolytic drugs, which may be additionally administered, can be significantly reduced.

[Carotid angiography by magnetic resonance]

Using magnetic resonance imaging, arteriosclerotic lesions of the supra-aortic vessels may be well demonstrated. The comparison between 3 magnetic resonance angiography (MRA) techniques (Spin Echo, Gradient Echo 2D FLASH, Gradient Echo 3D FISP) and Digital Subtraction Angiography (DSA) as reference in 50 patients suspicious of stenotic lesions proved the high reliability of these methods. Specially in determining the degree of stenosis, a good correlation between DSA and SE in 87%, between DSA and 2D FLASH in 78% and between DSA and 3D FISP in 83% could be assessed. Since 3D technique may exaggerate the degree of stenosis, we didn't observe any false negative result in severe stenosis. Therefore we think that the 3D technique is a safe technique which enables a good overview of the supra-aortic vessels and could therefore be suitable for screening.

Prognostic value of deoxyribonucleic acid aneuploidy in primary non-small-cell lung carcinomas and their metastases

The ploidy status of the deoxyribonucleic acid of a malignant lung tumor provides additional information besides histologic grading and tumor staging according to lymph node infiltration and tumor metastasis. Ninety-nine surgical specimens from patients with non-small-cell lung carcinoma were investigated by flow cytometry. Deoxyribonucleic acid aneuploidy was found in 48% of the primary tumors. Patients with deoxyribonucleic acid-euploid tumors showed better survival (p < 0.01) than those with deoxyribonucleic acid-aneuploid carcinomas independent of tumor stage. Deoxyribonucleic acid ploidy status of the primary tumor was compared with that of N2 lymph node metastases in 29 cases. Seven samples showed a change from deoxyribonucleic acid aneuploidy in the primary tumor to deoxyribonucleic acid euploidy in the lymph node metastases. Survival was significantly better for patients with euploid primary tumors and lymph node metastases, followed by patients with deoxyribonucleic acid-aneuploid primary tumors and euploid lymph node metastases. Survival was poorest in patients with deoxyribonucleic acid-aneuploid primary tumors and lymph node metastases. It was observed that only the simultaneous determination of deoxyribonucleic acid ploidy of primary tumors and lymph node metastases permits accurate prognostic evaluation in case of lymph node infiltration.

Crural arterial reconstruction with an adjunct arteriovenous fistula for limb salvage

Twenty-one femoro-crural bypass procedures with a distal arteriovenous fistula (dAVF) were constructed in 20 patients with severe leg ischemia (Fontaine stage III, IV). They were followed-up for 3 to 22 months, with a mean of 8 months. The 15 patients with patent grafts and fistulas no longer had pain at rest; ischemic necroses healed. Telethermography showed a considerable augmentation of the distal limb perfusion. The mean increase of the transcutaneous oxygen pressure was 30 mmHg. One early postoperative amputation was necessary due to graft infection. Another patient lost her leg because of bypass occlusion 9 months after arterial reconstruction. Four patients with late graft occlusion kept their regained mobility and alleviation. Our data confirm experimental results suggesting that femoro-crural bypass with a dAVF improves distal leg perfusion by reversal venous blood flow and stimulation of a collateral network. Femoro-crural bypass with a dAVF may be of benefit in selected cases when only one crural artery is patent and pedal arch vessels are absent.

Prenatal diagnosis of beta-thalassemia using selective hemolysis of maternal cells contaminating fetal blood sample

The prenatal diagnosis of the severe, hereditary anemias may be impossible when a placental blood sample which contains a high percentage of maternal rather than fetal cells is obtained. An incubation system described by Boyer et al. [3] with minor modifications, was applied to mixtures of blood from prematures and adults in order to increase the proportion of premature cells. After 40 min incubation, 95% or more of adult red cells were destroyed, whereas 30-60% of premature red cells were recovered, as determined by several independent methods. In a pregnancy at risk for beta-thalassemia, a placental blood sample which was purely fetal was obtained. Complete lack of in vitro beta-globin synthesis showed the fetus to have homozygous beta-thalassemia. When fetal blood was mixed with maternal blood in a ratio of 1:15, beta-globin synthesis in the mixture was comparable to that of normal fetuses. In contrast, when the cell mixture was subjected to selective hemolysis prior to separation of globins, beta-globin synthesis again was not detectable. Thus, using selective hemolysis, the correct diagnosis could be established from a blood sample containing only about 6% of fetal cells.