Brian Warren

Long-term results of stent graft treatment of subclavian artery injuries: management of choice for stable patients?

BACKGROUND The management of penetrating subclavian artery injuries poses a formidable surgical challenge. The feasibility of stent graft repair is already established. General use of this modality is not widely accepted due to concerns regarding the long-term outcome in a generally young patient population. We review our stent graft experience to examine long-term outcomes. METHODS All patients with penetrating subclavian artery injuries were evaluated for stent graft repair. Patients were excluded when hemodynamically unstable or unsuitable on other clinical and angiographic grounds. Patients were followed prospectively for early (<30 days) and late (>30 days) complications. Clinical and telephone evaluation, Doppler pressures, duplex Doppler, and angiography (when indicated), were used to asses patients at follow-up. Outcomes were recorded as technical success of procedure, graft patency, arm claudication, limb loss, the need for open surgical repair, the presence or absence of other complications, and death. RESULTS Fifty-seven patients underwent stent graft treatment during the 10-year period. Mean age was 34, and 91% were men. There were 53 stab wounds and four gunshot injuries. Pathology included false aneurysms (n = 42), arteriovenous fistula (n = 12), and three arterial occlusions. Early complications: One patient (2%) had a femoral puncture site injury which was managed with open surgical repair. One patient died early due to multiple organ failure related to concomitant injuries. Three patients (5%) presented with graft occlusion and nonlimb threatening ischemia in the first week after treatment. All three patients were managed successfully with a second endovascular intervention. Late complications: Twenty-five (44%) of the 57 patients with subclavian artery injuries were followed-up with a mean duration of 48 months. Two patients died as a result of fatal stab wounds months after their first injuries. Five patients (20%) and three patients (12%) presented with angiographically significant stenosis and occlusions, respectively. The stenotic lesions were successfully managed with endovascular intervention, and the occluded lesions were managed conservatively. No patient experienced life or limb loss or any incapacitating symptoms at the end of the study period. There was no need for conversion to open surgery. CONCLUSIONS This study has reaffirmed the feasibility and safety of stent graft repair in treating stable patients with selected penetrating subclavian artery injuries. The results of this study also confirmed acceptable long-term follow-up without any limb or life threatening complications. We conclude that endovascular repair should be considered the first choice of treatment in stable patients with subclavian artery injuries.

Duodenal injuries: surgical management adapted to circumstances

OBJECTIVES To evaluate the results of an evolving policy of primary repair of duodenal injuries, when considered feasible and safe, complemented by pyloric exclusion if any doubt as to the integrity of the repair existed. PATIENTS AND METHODS A prospective analysis of all patients with surgically identified duodenal injuries treated at a single institution over a 3-year period. RESULTS In 30 patients studied, there were four deaths (13%) and an overall complication rate of 47%. There were 68 associated intra-abdominal injuries in 29 patients. Primary duodenorraphy was employed in 18 patients (60%), pyloric exclusion in 11 (37%) and pancreatoduodenectomy in one patient (3%). No failures of duodenal repair were recorded. CONCLUSION Adverse results in patients with duodenal trauma are largely a reflection of frequent associated injuries and their consequences. Selective, liberal employment of pyloric exclusion, based on individualized intra-operative assessment, can minimize duodenum-related morbidity.

Endovascular management of traumatic cervicothoracic arteriovenous fistula

This study evaluated a single‐centre experience with endovascular repair of traumatic arteriovenous fistula in the cervicothoracic region.

Efficacy and safety of ertapenem versus piperacillin-tazobactam for the treatment of intra-abdominal infections requiring surgical intervention

Complicated intra-abdominal infections usually mandate prompt surgical intervention supplemented by appropriate antimicrobial therapy. The aim of this study was to demonstrate that ertapenem was not inferior to piperacillin-tazobactam for the treatment of community-acquired intra-abdominal infections. A randomized open-label active-comparator clinical trial was conducted at 48 medical centers on four continents from December 2001 to February 2003. Adult patients with intra-abdominal infections requiring surgery were randomized to receive either ertapenem 1 g daily or piperacillin/tazobactam 13.5 g daily in 3–4 divided doses. The primary analysis of efficacy was the clinical response rate in clinically and microbiologically evaluable patients at the test-of-cure assessment 2 weeks after completion of therapy. All treated patients were included in the safety analysis. Patient demographics, disease characteristics, and treatment duration in both treatment groups were generally similar. The most commonly isolated pathogens at baseline were E coli (greater than 50% of cases in each group) and B fragilis (~9%). Favorable clinical response rates were 107/119 (90%) for ertapenem recipients and 107/114 (94%) for piperacillin/tazobactam recipients. The frequencies of drug-related adverse events, most commonly diarrhea and elevated serum alanine aminotransferase levels, were similar in both treatment groups. Six of 180 ertapenem recipients (3%) and two of 190 piperacillin/tazobactam recipients (1%) had serious drug-related adverse experiences. In this study, ertapenem and piperacillin/tazobactam were comparably safe and effective treatments for adult patients with complicated intra-abdominal infections.

Neurologic outcome after penetrating extracranial arterial trauma

PURPOSE We undertook this study to determine factors that adversely affect outcome in patients with penetrating injury to the extracranial cerebral vasculature. Patients and methods Medical records were reviewed for all patients who had undergone surgical intervention to treat penetrating injury to the extracranial cerebral arteries between January 1989 and December 1999. Forensic autopsy findings were also reviewed for all patients who died as a result of their injury. RESULTS One hundred fifty-one patients with injury to the brachiocephalic artery (n = 21), common carotid artery (n = 98), or internal carotid artery (n = 32) were identified. Overall mortality was 21.2%, and stroke rate in surviving patients was 15.1%. Twenty-five of 32 deaths (78.1%) were stroke-related. Brachiocephalic artery injury was associated with the highest mortality (38.1%), and survivor stroke rate was highest in patients with internal carotid injuries (22.7%). Hemodynamic instability at presentation led to both higher mortality (30.7%) and stroke rate (19.2%). Preoperative angiography did not influence mortality or stroke rate in hemodynamically stable patients. Procedural mortality associated with arterial ligation was 45% (9 of 20 patients), and no surviving patient experienced a change in pre-ligation neurologic state. Nine patients remained neurologically intact after ligation, and 2 patients with preoperative localized neurologic deficit were unchanged postoperatively. In 131 patients, mortality after arterial repair was 17.6%, and in 5 surviving patients (5.4%) an ischemic neurologic deficit developed. Twelve of 15 surviving patients (80%) with preoperative neurologic deficit who underwent arterial repair had improved neurologic status. Cerebral infarcts were confirmed at autopsy in 23 patients; 18 infarcts were ischemic (10, repair; 8, ligation), and 5 infarcts were hemorrhagic (all, repair). No factor was identified that was predictive of ischemic versus hemorrhagic infarction in patients undergoing repair. CONCLUSIONS The presence of hypovolemic shock, internal carotid artery injury, complete vessel transection, and arterial ligation are associated with unfavorable outcome. Penetrating injury to the brachiocephalic, common carotid, or internal carotid artery should be repaired rather than ligated when technically possible. Subsequent ischemic or hemorrhagic cerebral infarction is unpredictable, but overall outcome is superior to that with ligation of the injured artery.

Pharmacokinetics of recombinant activated factor VII in trauma patients with severe bleeding

IntroductionRecombinant activated factor VII (rFVIIa) has been used as adjunctive therapy in trauma patients with severe bleeding. However, its pharmacokinetics profile remains unknown.MethodsIn two placebo-controlled studies in patients with blunt and penetrating trauma, the pharmacokinetics of rFVIIa given at an initial dose of 200 μg.kg-1 after transfusion of eight red blood cell units, followed by additional doses of 100 μg.kg-1, one and three hours later, have been studied, based on the FVII coagulant activity assay. Both non-compartment and population pharmacokinetic analyses were performed. A two-compartment, population pharmacokinetic model was used to estimate a population profile for the rFVIIa dosing regimen. Data are population means (percent coefficient of variation (CV)).ResultsBased on the two-compartment population model, the estimated pharmacokinetic parameters were: clearance 40 (30% CV) ml.kg-1.h-1; central volume of distribution 89 (32% CV) ml.kg-1; inter-compartmental clearance 24 ml.kg-1.h-1; and peripheral compartment volume 31 ml.kg-1. Baseline FVII coagulant activity was estimated at 0.29 (39% CV) U.ml-1, initial half-life was 0.6 (34% CV) hours, and terminal half-life 2.4 (50% CV) hours. High intra- and inter-patient variability was noted in volume of distribution and clearance, which was in part correlated with the transfusion requirements as the single significant covariate. The non-compartmental analysis led to almost identical estimates of key parameters.ConclusionA high intra- and inter-patient variability was noted in the volume of distribution and clearance of rFVIIa in trauma patients with severe bleeding, mainly related with the transfusion requirements and thus blood loss and/or bleeding rate.

The Endovascular Management of Penetrating Carotid Artery Injuries: Long-term Follow-up

OBJECTIVES To review a single-centre experience with stent-graft treatment of penetrating carotid artery injuries and long-term follow-up. METHODS All stable patients with carotid artery injuries presenting between August 1998 and February 2009 were considered for endovascular treatment. Patients were selected based on clinical and radiological criteria and data were prospectively collected. Follow-up was conducted clinically, angiographically and by telephonic contact. Endpoints were stroke, death and any other stent-graft-related complications. RESULTS A total of 128 patients were treated, of whom only 19 were selected for endovascular management. The recorded technical success rate was 100%, with one early stroke and one non-stent-graft-related procedural death. A further four patients were lost to follow-up. The remaining 14 patients had a mean follow-up of nearly 4 years. No stent-graft-related late deaths, strokes or other complications were reported, although one instance of late stent-graft occlusion was documented. CONCLUSION Endovascular management of penetrating carotid artery injuries is safe and the long-term outcomes justify a more liberal application of this technique in selected patients.

Surgical and Endovascular Management of Penetrating Innominate Artery Injuries

OBJECTIVE To review our management of penetrating innominate artery injuries by open and endovascular techniques. METHODS Data regarding patient demography, clinical presentation, investigations, associated injuries, pathology, management, complications and mortality, were collected on patients treated at a single centre over 18 years. RESULTS 39 innominate artery injuries were treated. There were 36 men and three women, with a mean age of 27 years (range 18-49). Thirty-eight injuries were due to stabwounds and one was the result of a gunshot wound. The most common clinical presentations were shock (47%) and haematoma(42%). Twenty-three patients had associated injuries. The most common pathology was false aneurysm in 21 patients followed by 13 actively bleeding injuries, 4 arteriovenous fistulas and 1 arterial occlusion. Thirty-four patients underwent surgical and five endovascular repair. Overall survival was 79%. The stroke rate for surviving patients was 6%. Patients treated with endovascular stenting had shorter hospital and intensive care unit stays than those treated with surgery. CONCLUSIONS Innominate artery injuries have high rates of morbidity and mortality. A vascular surgical approach with pre-operative angiography, when possible and careful surgical planning by a dedicated team promotes better surgical results. Endovascular and hybrid procedures can become the method of choice when treating stable patients.

Endovascular Repair of Occluded Subclavian Arteries following Penetrating Trauma

Purpose: To describe the endovascular repair of 2 subclavian arteries occluded due to penetrating trauma. Case Reports: Two male patients were admitted with zone-I neck stab wounds. Both were hemodynamically stable and had absent pulses in the ipsilateral upper limb with decreased Doppler pressures. There were no signs of critical ischemia or active bleeding. On arteriography, complete occlusion of the second segment of the left subclavian arteries in both patients was demonstrated. Stent-graft repair and embolectomy under local anesthesia were successfully performed. No procedure-related complications occurred, and both patients were discharged after 2 days. At 1-year follow-up, stent-graft patency was demonstrated in both patients. Conclusions: Endovascular repair is a feasible and safe option in the management of occluded subclavian arteries due to penetrating trauma. This may represent another indication for stent-grafting in the expanding role of this technique.

Prolonged Prothrombin Time After Recombinant Activated Factor VII Therapy in Critically Bleeding Trauma Patients Is Associated With Adverse Outcomes

BACKGROUND In trauma patients with significant hemorrhage, it is hypothesized that failure to normalize prothrombin time (PT) after recombinant activated factor VII (rFVIIa) treatment predicts poor clinical outcomes and potentially indicates a need for additional therapeutic interventions. METHODS To assess the value of PT to predict outcomes after rFVIIa or placebo therapy, we performed a post hoc analysis of data from 169 severely injured, critically bleeding trauma patients who had 1-hour postdose PT measurements from two randomized clinical trials. Baseline characteristics and outcome parameters were compared between subjects with 1-hour postdose PT >or=18 seconds and PT <18 seconds. RESULTS In rFVIIa-treated subjects, prolonged postdose PT values >or=18 seconds were associated with significantly higher 24-hour mortality (60% vs. 3%; p < 0.001) and 30-day mortality, increased incidence of massive transfusion, and fewer intensive care unit-free days compared with postdose PT values <18 seconds. Recombinant rFVIIa-treated subjects with postdose PT >or=18 seconds had significantly lower baseline hemoglobin levels, fibrinogen levels, and platelet counts than subjects with postdose PT values <18 seconds even though they received similar amounts of blood products before rFVIIa dosing. Placebo-treated subjects with postdose PT >or=18 seconds had significantly increased incidence of massive transfusion, significantly decreased intensive care unit-free days, and significantly lower levels of fibrinogen and platelets at baseline compared with subjects with postdose PT values <18 seconds. CONCLUSIONS The presence of prolonged PT after rFVIIa or placebo therapy was associated with poor clinical outcomes. Because subjects with postdosing PT >or=18 seconds had low levels of hemoglobin, fibrinogen, and platelets, this group may benefit from additional blood component therapy.