Yvonne M. Carter

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.

Limb loss following lower extremity arterial trauma: what can be done proactively?

We performed a retrospective review of patients admitted to two Level I trauma centres over a 15-year period with arterial injuries (excluding primary amputations). Preoperative factors analysed included mechanism of injury, site and type of arterial and venous injury and repair, time to operating room, initial blood pressure, evidence of ipsilateral limb fracture and/or extensive tissue damage, status of preoperative pulses and angiographic data. One hundred and fifty-one arterial injuries were treated (80 penetrating). Overall mortality was 10 (6.6%) and limb loss 16 (10.6%). Only two factors that might possibly be modified by specific interventions were noted. The incidence of limb loss was higher in patients who developed compartment syndrome (41% versus 7% without, P=0.003) and in those who did not receive intra- or immediately postoperative anticoagulation (15% without versus 3% with, P=0.02). Unfortunately, no factor was found that reliably predicted the risk of compartment syndrome. In addition, patients who did not receive peri-operative anticoagulation were more severely injured than those that did were. Despite this, there were no bleeding complications associated with anticoagulation. These findings suggest that the primary interventions that may improve limb salvage include liberal use of fasciotomy (recognising that any patient may require this) as well as early use of anticoagulation.

Deep venous thrombosis and ABO blood group are unrelated in trauma patients.

BACKGROUND Although epidemiologic studies of the general population have demonstrated a deficit of blood group O among patients with deep venous thrombosis (DVT), few studies have evaluated the importance of blood group in high-risk patients. The purpose of this study was to evaluate the importance of ABO blood group as a thrombotic risk factor in injured patients. METHODS Injured patients with a discharge diagnosis of DVT were identified from an institutional trauma registry and compared with control patients matched for age and Injury Severity Score. ABO blood types of patients and controls were obtained from the regional blood center database. RESULTS Three hundred forty-three case-control pairs were identified from a total of 401 consecutive cases of DVT. Blunt injury was the predominant mechanism of injury, accounting for 90.4% of cases. Chest (p = 0.01) and extremity (p < 0.001) Abbreviated Injury Scale scores were independent predictors of DVT. However, there was no significant difference in blood group distribution or the A to O ratio between patients with and without DVT. For non-type O patients, the odds ratio for developing DVT was 1.1 (95% confidence interval, 0.8-1.5; p = 0.5) in comparison with type O patients. CONCLUSION These data do not support a clinically relevant association between blood type and DVT in trauma patients. Injury-associated derangements of coagulation may be more important than any hypercoagulability related to blood type in this population.

Choice of venous cannulation for bypass during repair of traumatic rupture of the aorta

BACKGROUND Choices for venous cannulation for left heart bypass, to assist repair of traumatic rupture of the thoracic aorta, are between the left atrial appendage and pulmonary veins. METHODS A retrospective chart review was performed of patients who underwent operative repair of ruptured aorta. RESULTS Over a 15-year period between March 1985 and February 2000, 133 patients were admitted to a level I trauma center with aortic rupture. Of the 50 procedures performed with left heart bypass, the left atrial appendage was cannulated in 19 and pulmonary veins in 31 (four superior, 27 inferior). Complications occurred in 7 of the 19 patients who underwent venous cannulation via the atrial appendage (two ventricular fibrillation, three atrial fibrillation, one pericardial effusion leading to tamponade, and one phrenic nerve injury). Complications occurred in 2 patients who underwent cannulation via pulmonary vein (one atrial fibrillation, one pericardial effusion requiring tapping) (p = 0.02). CONCLUSIONS Cannulation via the pulmonary veins is associated with a decrease in complication rates compared with cannulation of the atrial appendage.

Delayed surgical management of a traumatic aortic arch injury

We report successful management of a blunt traumatic injury to the aortic arch with intentionally delayed surgical repair. The aorta was repaired after the stabilization of other, potentially fatal, traumatic injuries.

Intracoronary E-/L-selectin blockade reduces neutrophil infiltration in heart transplantation

BACKGROUND This study examined the effect of local intracoronary delivery of a unique monoclonal antibody (mAb) to both E- and L-selectin (EL-246) on neutrophil infiltration after global ischemia during cardiac transplantation. METHODS In 12 ovine heart transplants, allograft coronary arteries were locally perfused with EL-246 (n = 6), or isotype-matched control antibodies (n = 2) or saline (n = 4). At 24 hours posttransplant, myocardium was analyzed for neutrophil infiltration and myocardial water content. RESULTS The mean number of intramyocardial neutrophils per area (PMN/hpf) was greatly reduced in the allografts perfused with EL-246 (3.45 +/- 0.4 PMN/hpf), compared with an average 6.5 +/- 0.97 PMN/hpf in control hearts (p = 0.004). Peripheral leukocyte counts were unaffected; myocardial water content was not significantly reduced. CONCLUSIONS Local perfusion of cardiac allografts with blocking antibody EL-246 before reperfusion significantly reduced the neutrophilic infiltration that occurs early after transplantation. Prohibiting neutrophil-endothelial adhesion and transmigration may be useful in decreasing neutrophil-dependent post-reperfusion injury in transplantation and routine cardiac surgery.

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.