Robert D. Bloch

Natural history of traumatic rupture of the thoracic aorta managed nonoperatively: a longitudinal analysis

BACKGROUND Although traumatic rupture of the thoracic aorta (TRA) has traditionally been considered a surgical emergency, there exists a small patient population for whom nonoperative management may be appropriate. The short- and long-term consequences of patients managed in a nonoperative fashion remain unclear. METHODS A review of patients admitted with TRA over a period of 16 years was performed. Patients who did not undergo operative repair within 24 hours of injury and diagnosis comprised the study group. RESULTS One hundred forty-five patients were admitted with TRA. Of these, 30 underwent a period of nonoperative management. The mean age of the study patients was 44 +/- 21 years, 80% were male, and the mean Injury Severity Score (ISS) was 34 +/- 9. Fifteen patients underwent delayed operation (DELAY group) at more than 24 hours after injury and diagnosis and 15 patients never underwent repair (NON-OP group). The median time to operation in the DELAY group was 3 days (range 2 to 90). Three patients exhibited progression of TRA within 5 days of injury and of these, 2 died. A total of 3 deaths occurred in the DELAY group (1 rupture and 2 intraoperative arrests). The fifteen NON-OP patients were significantly older (mean age 52 +/- 22 versus 36 +/- 18 years; p = 0.03), tended to be more severely injured (mean ISS 36 +/- 9 versus 32 +/- 8; p = 0.2), and had more premorbid risk factors than the DELAY patients. Five NON-OP patients died, all because of severe head injuries. On long-term follow-up of NON-OP patients, all 10 survivors are alive at a median of 2.5 years (range 6 months to 5 years) without progression of injury or the need for operation. Five of the 10 had complete radiographic resolution of their injuries and 5 have asymptomatic and radiographically stable pseudoaneurysms. CONCLUSIONS Selected patients with multiple severe associated injuries or high-risk premorbid conditions may have their operations for TRA delayed temporarily or even indefinitely with acceptable survival rates. The potential for rapid progression of TRA in the same patients, however, mandates serial radiographic examinations during the first week of hospitalization after injury and diagnosis.

Angiographic description of blunt traumatic injuries to the thoracic aorta with specific relevance to endograft repair.

Purpose: To describe the precise anatomical location and extent of injury (based on angiography) in a series of patients with blunt thoracic aortic injury (BTAI) and evaluate the findings relative to the potential for endograft repair. Methods: Thoracic aortograms from 50 trauma patients (37 men; mean age 37 years, range 13–87) with BTAI were retrospectively reviewed. Parameters important for endograft repair were recorded, including the length of the pseudoaneurysm, the distance between the origin of the most distal arch vessel and the pseudoaneurysm, the diameter of the aorta both above and below the pseudoaneurysm, and finally, the curvature of the aorta in the vicinity of the pseudoaneurysm. Results: The mean distance from the left subclavian artery to the superior aspect of the injury measured 5.8 mm along the lesser curve and 14.9 mm along the greater curve. The mean length of the injury was 17.0 mm and 26.0 mm along the lesser and greater curves, respectively. The mean aortic diameter adjacent to the injury measured 19.3 mm. The mean degree of curvature of the aorta over the length of the injury was 27.2°, with a mean radius of curvature of 32.6 mm at the superior aspect of the injury and 39.3 mm inferiorly. Conclusions: In most cases of BTAI, the location of the injury will necessitate covering the origin of the left subclavian artery if endovascular repair is to be performed. The curvature of the aorta in the region predisposed to these injuries requires that the endograft be very flexible and/or precurved.

Management of traumatic rupture of the thoracic aorta in pediatric patients

BACKGROUND Traumatic rupture of the thoracic aorta (TRA) in the pediatric population is uncommon. Management of TRA in general has evolved to include selective nonoperative and endovascular stent graft approaches, although operative repair remains the standard. METHODS We conducted a retrospective chart review of patients younger than 16 years of age admitted to a single institution between March 1985 and February 2002. RESULTS Of 160 patients admitted with TRA, 11 were younger than 16 (11.9 +/- 3.5) years of age. Concomitant injuries included closed head injury (5 patients) and acute lung injury (6 patients). All were started on beta-blockers when the diagnosis was suspected. Laparotomy was required in 3 patients and orthopedic procedures in 5 patients. Six underwent operative repair (two primary repairs), with no mortality. Cross-clamp time was 30.4 +/- 2.6 minutes. One patient (operated on without bypass) was partially paralyzed. Two patients were managed nonoperatively, 1 with an intimal arch injury, who on subsequent follow-up has demonstrated healing, and 1 who died of head injury. Three patients were managed by endovascular stent grafts, 2 who died of closed head injury and 1 who at 1-year follow-up has fully recovered. The endovascular stent grafts were placed through the femoral artery in 2 patients and through an iliac conduit in 1 patient. No patient died of rupture. CONCLUSIONS The approach to pediatric TRA should be identical to the adult, with early institution of beta-blockers. Depending on the clinical setting, a spectrum of options should be considered, including operation, non-operation, and endovascular stent graft, although the choice of the latter must be tempered by the lack of long-term follow-up data.

Stent-Grafts for De Novo TIPS: Technique and Early Results

PURPOSE To evaluate the potential benefits of placing a polytetrafluoroethylene (PTFE)-covered stent-graft during initial creation of a transjugular intrahepatic portosystemic shunt (TIPS) in clinical practice. MATERIALS AND METHODS De novo TIPS were created with a PTFE stent-graft in four male and four female patients with symptomatic portal hypertension awaiting liver transplant. Their ages ranged from 35 to 62 (mean, 47) years. Patients were followed with TIPS ultrasound (US) and/or venography until liver transplantation or death; one remains under active study. Six recovered specimens underwent gross and microscopic evaluation. RESULTS All TIPS placements were successful. Six shunts were primarily patent, with a mean patency of 289 days, through completion of the study. Five were found to be patent at transplant and one was found to be patent at autopsy. Explant evaluation revealed a smooth, thin layer of neointima and exclusion of biliary secretions. Three patients developed a total of four stenoses (one tandem lesion) during follow-up, leading to revision in two patients. Mean primary and total patency in these patients was achieved after 279 and 463 days, respectively. A previously occult moderate stenosis was detected after explant in another patient. Only one (nonsignificant) stenosis clearly developed in an area covered by PTFE. CONCLUSION Placement of a de novo PTFE stent-graft during TIPS creation is feasible and may extend primary shunt patency. Appropriate positioning of the stent-graft is critical.

Management of pulmonary embolism with rheolytic thrombectomy

BACKGROUND Catheter thrombectomy combining thrombus destruction with local thrombolysis has been used in patients with pulmonary embolism (PE) who are unstable or have significant right heart dysfunction, but have contraindications to systemic thrombolytic therapy. OBJECTIVES To assess the outcomes of patients who underwent pulmonary embolectomy using a commercially available thrombectomy device. METHODS A retrospective chart review of patients who underwent pulmonary embolectomy between March 2007 and August 2009 was performed. Patients were classified as having clinical massive or submassive PE, and moderate or severe right ventricular dysfunction. Data collected included pre- and postprocedure shock index (heart rate divided by systolic blood pressure) and mean pulmonary artery pressure. RESULTS Sixteen patients with a mean (± SD) age of 54.4 ± 15.8 years underwent embolectomy. Five had clinical massive PE (two in cardiogenic shock) and three of 11 submassive cases had severe right ventricular dysfunction. All were deemed to have contraindications to systemic lysis. Both shock index (1.02 ± 33 preintervention versus 0.71 ± 0.2 postintervention [P=0.001]) and mean pulmonary artery pressure (34.5 ± 9.9 mmHg preintervention versus 27.1 ± 7.1 postintervention [P=0.01]) improved. In the massive PE group, one patient died and two survivors experienced retroperitoneal bleeding and transient renal failure. At follow-up (17.3 ± 7.8 months), two patients in the massive PE group demonstrated evidence of mild cor pulmonale. CONCLUSION Rheolytic thrombectomy is an effective strategy in managing massive PE, particularly in patients who have well-defined contraindications to systemic lytic therapy. The effectiveness of rheolytic thrombectomy for submassive PE is not as well defined, but warrants a comparison with systemic lytic therapy.

An evaluation of commonly employed central venous catheter kits and their potential risk for complications of excess guidewire introduction.

STUDY OBJECTIVE To evaluate the components of commonly used central venous catheter kits with respect to the potential for guidewire-mediated complications during catheter placement.Prospective, nonrandomized, observational study. SETTING Six academic hospitals across the United States. PATIENTS None. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS 30 commercially manufactured catheter kits (15 tunneled, 15 nontunneled) were opened and evaluated. The catheter or sheath to be introduced was measured and a corresponding ideal guidewire length was calculated. The ideal length was then compared to the actual length, and differences were tabulated. Wire tip configuration and the presence and pattern of distance markings were recorded and, in conjunction with the catheter and wire length discrepancies, were used to grade the relative risk of introducing excess guidewire during catheter placement. Of 30 kits evaluated, 14 (46.7%) had guidewires more than 20 cm longer than necessary. The mean excess wire length was 15 cm (range: 8 to 55 cm) and did not differ significantly between tunneled and nontunneled catheter kits. Only 10 kits (33.3%) had distance markings of any type, and there was no standardization among them; none corresponded to previously published recommendations. There was potential risk of excess wire introduction in 18 catheter kits, of which seven were nontunneled devices designed for bedside placement. CONCLUSIONS The design of commonly employed central venous access catheter kits is such that there is a mismatch between guidewire and catheter length and a general lack of guidewire markings. We believe that these designs may predispose to the introduction of excess guidewire and result in guidewire-mediated complications during catheter placement. This risk can likely be reduced by matching the guidewires to the devices placed over them and by standardizing guidewire distance markings.

CT-guided transfemoral portocaval shunt creation.

A patient with superior vena cava (SVC) occlusion presented with severe ascites and urgent transjugular intrahepatic portosystemic shunt (TIPS) was requested. The patient had a chronically occluded SVC. An alternative to classic TIPS was employed using CT guidance to traverse the left portal vein to the inferior vena cava with a small gauge needle. Fluoroscopic guidance was then used to snare a wire placed through the needle and then work from the femoral vein to create a portocaval shunt that passed through the caudate lobe. This procedure was a technical success and improved the patient’s ascites.

Ehlers-Danlos Syndrome Mimicking Mesenteric Vasculitis: Therapy, then Diagnosis

The etiology of acute intraabdominal bleeding is often unclear at the time emergent arteriography is performed. During localization and embolization, the arteriogram may suggest the diagnosis of vasculitis. However, controlling the bleeding remains the priority. Connective tissue diseases such as Ehlers-Danlos syndrome (EDS) may also cause bleeding and mimic vasculitis and must be included in the differential diagnosis. We present such a case in which the initial findings were misleading.

Endovascular approach to acute aortic trauma

Traumatic thoracic aortic injury remains a major cause of death following motor vehicle accidents. Endovascular approaches have begun to supersede open repair, offering the hope of reduced morbidity and mortality. The available endovascular technology is associated with specific anatomic considerations and complications. This paper will review the current status of endovascular management of traumatic thoracic aortic injuries.

Massive Pulmonary Embolus

Pulmonary embolus is usually a complication iliofemoral venous thrombosis (≥ 90%). However, the incidence of upper extremity deep venous thrombosis (DVT) has recently increased, and is attributed to the use of central monitoring catheters. Regardless of the source, a DVT was documented in only 34% of patients suffering pulmonary emboli in the National Cooperative Study. In addition, pulmonary embolism is often a subclinical event, with a higher incidence at autopsy than suspected during any given patients clinical course. Although the majority of these patients have identifiable risk factors, the mortality from pulmonary embolism remains significant.