John Harlock

Mortality associated with withdrawal of life-sustaining therapy for patients with severe traumatic brain injury: a Canadian multicentre cohort study

Background: Severe traumatic brain injury often leads to death from withdrawal of life-sustaining therapy, although prognosis is difficult to determine. Methods: To evaluate variation in mortality following the withdrawal of life-sustaining therapy and hospital mortality in patients with critical illness and severe traumatic brain injury, we conducted a two-year multicentre retrospective cohort study in six Canadian level-one trauma centres. The effect of centre on hospital mortality and withdrawal of life-sustaining therapy was evaluated using multivariable logistic regression adjusted for baseline patient-level covariates (sex, age, pupillary reactivity and score on the Glasgow coma scale). Results: We randomly selected 720 patients with traumatic brain injury for our study. The overall hospital mortality among these patients was 228/720 (31.7%, 95% confidence interval [CI] 28.4%–35.2%) and ranged from 10.8% to 44.2% across centres (χ2 test for overall difference, p < 0.001). Most deaths (70.2% [160/228], 95% CI 63.9%–75.7%) were associated with withdrawal of life-sustaining therapy, ranging from 45.0% (18/40) to 86.8% (46/53) (χ2 test for overall difference, p < 0.001) across centres. Adjusted odd ratios (ORs) for the effect of centre on hospital mortality ranged from 0.61 to 1.55 (p < 0.001). The incidence of withdrawal of life-sustaining therapy varied by centre, with ORs ranging from 0.42 to 2.40 (p = 0.001). About one half of deaths that occurred following the withdrawal of life-sustaining therapies happened within the first three days of care. Interpretation: We observed significant variation in mortality across centres. This may be explained in part by regional variations in physician, family or community approaches to the withdrawal of life-sustaining therapy. Considering the high proportion of early deaths associated with the withdrawal of life-sustaining therapy and the limited accuracy of current prognostic indicators, caution should be used regarding early withdrawal of life-sustaining therapy following severe traumatic brain injury.

Mortality and reintervention following elective abdominal aortic aneurysm repair.

BACKGROUND The objective of this study is to provide an up-to-date meta-analysis on the short- and long-term mortality rates of elective repair of abdominal aortic aneurysms (AAAs) via the open and endovascular approaches. METHODS MEDLINE, EMBASE, and Cochrane Central Register of Controlled trials, conference proceeding from major vascular meetings were searched for randomized trials comparing open vs elective endovascular aneurysm repair (EVAR) of AAAs. A random-effects model was used for analysis. Risk ratio (RR) and 95% confidence intervals (CIs) of open vs EVAR were calculated for short- and long-term mortality and reintervention rates. RESULTS The analysis encompassed four randomized controlled trials with a total of 2783 patients. The open repair group resulted in significantly increased 30-day postoperative all-cause mortality compared with EVAR repair group (3.2% vs 1.2%; RR, 2.81; 95% CI, 1.60-4.94); however, there is no statistical difference in the long-term all-cause mortality between both groups (RR, 0.97; 95% CI, 0.86-1.10). Interestingly, fewer patients underwent reintervention procedures in the open repair group compared with those who had EVAR repair (9.3% vs 18.9%; RR, 0.49; 95% CI, 0.40-0.60), but this finding is doubtful due to the large heterogeneity. Lastly, no statistical difference in long-term mortality rates attributable to cardiovascular disease (CVD), aneurysm related, or stroke were found between the two types of repair. CONCLUSIONS Results of this meta-analysis demonstrate that the 30-day all-cause mortality rate is higher with open than with EVAR repair; however, there is no statistical difference in the long-term all-cause and cause-specific mortality between both groups. The reintervention rate attributable to procedural complication was higher in the EVAR group. Because of the equivalency of long-term outcomes and the short-term benefits of EVAR, an endovascular-first approach to AAAs can be supported by the meta-analysis.

Myocardial Injury After Noncardiac Surgery (MINS) in Vascular Surgical Patients: A Prospective Observational Cohort Study.

Objective: To determine the prognostic relevance, clinical characteristics, and 30-day outcomes associated with myocardial injury after noncardiac surgery (MINS) in vascular surgical patients. Background: MINS has been independently associated with 30-day mortality after noncardiac surgery. The characteristics and prognostic importance of MINS in vascular surgery patients are poorly described. Methods: This was an international prospective cohort study of 15,102 noncardiac surgery patients 45 years or older, of whom 502 patients underwent vascular surgery. All patients had fourth-generation plasma troponin T (TnT) concentrations measured during the first 3 postoperative days. MINS was defined as a TnT of 0.03 ng/mL of higher secondary to ischemia. The objectives of the present study were to determine (i) if MINS is prognostically important in vascular surgical patients, (ii) the clinical characteristics of vascular surgery patients with and without MINS, (iii) the 30-day outcomes for vascular surgery patients with and without MINS, and (iv) the proportion of MINS that probably would have gone undetected without routine troponin monitoring. Results: The incidence of MINS in the vascular surgery patients was 19.1% (95% confidence interval (CI), 15.7%–22.6%). 30-day all-cause mortality in the vascular cohort was 12.5% (95% CI 7.3%–20.6%) in patients with MINS compared with 1.5% (95% CI 0.7%–3.2%) in patients without MINS (P < 0.001). MINS was independently associated with 30-day mortality in vascular patients (odds ratio, 9.48; 95% CI, 3.46–25.96). The 30-day mortality was similar in MINS patients with (15.0%; 95% CI, 7.1–29.1) and without an ischemic feature (12.2%; 95% CI, 5.3–25.5, P = 0.76). The proportion of vascular surgery patients who suffered MINS without overt evidence of myocardial ischemia was 74.1% (95% CI, 63.6–82.4). Conclusions: Approximately 1 in 5 patients experienced MINS after vascular surgery. MINS was independently associated with 30-day mortality. The majority of patients with MINS were asymptomatic and would have gone undetected without routine postoperative troponin measurement.

Hybrid repair of symptomatic aberrant right subclavian artery and Kommerell's diverticulum.

INTRODUCTION An aberrant right subclavian artery (ARSA) with or without an associated Kommerells diverticulum (KOD) is a rare vascular anomaly. Patients with an ARSA may present with a variety of symptoms, including rupture. Options for repair include open, endovascular, and a hybrid approach, with no clear consensus on which is best because of the rarity of the anomaly. We present 2 cases that underwent hybrid repair and a systematic review of the literature. METHODS A systematic review of the literature was performed from 2000-2012 searching for patients with ARSA with or without KOD who underwent endovascular repair. Twenty-four articles were identified, including a few case reports and small case series, for a total of 31 patients. A chart review was also performed on 2 patients at our institution who underwent a hybrid repair for symptomatic ARSA. RESULTS We report the presenting history, management, and follow-up of 2 symptomatic patients with ARSA with associated KOD. Both patients underwent a hybrid approach for repair, with no reported complications. After postoperative imaging and clinical follow-up, both patients remained in good general condition without signs of vascular complications. Our systematic literature review identified 31 reported cases of patients with ARSA who underwent endovascular repair (10 patients without an associated KOD and 21 patients with a KOD). The patients ranged in age from 21-82 years of age (average: 56 years). Of these patients, 17 (55%) were women. The presenting symptoms varied, and some patients had multiple symptoms noted on presentation, including dysphagia, dyspnea, or asymptomatic patients. In those patients with an associated KOD, the average size of the diverticulum was 3.3 cm (range: 2.3-7 cm). A number of operative strategies were used in the reported cases, depending on the presence of absence of an associated KOD. The average reported duration of hospital stay was 5.4 days (range: 1-60 days). Seven patients had postoperative complications (22%). There were 3 mortalities reported (10%). Only 1 of these could be directly related to the surgical procedure. Reported decrease in aneurysm size was between 25-50%, although this was not reported for most patients. Four of 31 patients (13%) had an endoleak (1 type I endoleak, 2 type II endoleaks, and 1 type IV endoleak). The range of reported follow-up varied between 6 weeks and 92 months, with 9 patients having no follow-up reported. CONCLUSION Hybrid approach to repair of an ARSA with associated KOD appears to be feasible, safe, and effective. Despite the poor quality and heterogeneity of the evidence available in the literature for this rare condition, we believe that this could be the preferred treatment option for an ARSA either with or without KOD.

Infected Aortic Stent Graft With Propionibacterium acnes

An infected aortic endograft is an uncommon event, and when it happens it can be of significant morbidity and mortality to the patient. We present here a case of a patient with an infected aortic endograft following percutaneous translumbar sac embolization for a type II endoleak leading to sac expansion. The cultured pathogen was Propionibacterium acnes, a commonly occurring skin bacterium that leads to the clinical condition “acne vulgaris.” The patient underwent graft explantation and reconstruction with autogenous femoral vein. To our knowledge, there are no previously published reports of aortic graft infections with P acnes.

Laser Therapy for an Obstructing Primary Tracheal Lymphoma in a Patient With AIDS

A patient with AIDS presented with progressive dyspnea leading to respiratory failure with near complete airway obstruction due to primary tracheal lymphoma. Laser therapy was used locally to debulk the tumour, which facilitated extubation and led to definitive treatment with chemotherapy. Alternatives for local airway control are discussed.

A new and forgotten indication for aortic fenestration.

Surgical aortic fenestration for acute aortic dissection was first described by Shaw in 1955. Since then, it has rapidly been surpassed in use by percutaneous fenestration. Williams et al. first reported this technique and described two indications: to treat malperfusion syndromes and to provide a re-entry tear for a ‘‘dead-end’’ false lumen. The latter indication was stated as hypothetical in order to prevent thrombosis (and subsequent branch vessel compromise) or extension of the false lumen (and presumably risk of rupture). In this issue of JEVT, Tolenaar et al. report a case of aortic dissection following endovascular infrarenal aortic aneurysm repair. Thus far, in the literature, this remains an uncommon event. The authors describe percutaneous aortic fenestration to treat persistent pain, without evidence of organ malperfusion. The main indication was to prevent progression of the false lumen and subsequent stent-graft collapse, as previously described by Iyer et al. Most reports of aortic fenestration are for the treatment of malperfusion. Equilibration of pressures between the true and false lumens has clinically been demonstrated; however, the false lumen pressure was not decreased, according to a study by Williams et al., so, theoretically, the long-term risk of expansion and rupture remains. Experimental models have suggested that the location of fenestrations, as well as their size, may play a role in determining relative pressures in the true and false lumens. For example, proximal fenestrations may serve as additional entry tears, whereas distal fenestrations act more like re-entry tears that will decompress the false lumen. Of course, proximal and distal remain relative and rather vague in a classical dissection. However, in the case described by Tolenaar and colleagues, the initial entry tear was presumably at the bare stent of the abdominal aortic stent-graft, although we cannot be certain of this. The subsequent re-entry into the true lumen occurred in proximity to the left subclavian artery (via retrograde dissection), which then served as the new antegrade entry tear into the false lumen. The original entry tear must not have been sufficient to allow decompression of the false lumen, essentially creating a ‘‘dead-end’’ false lumen. (This is, of course, only a hypothesis, which could be studied in the laboratory). Concern over myelum ischemia prohibited coverage of the proximal tear with an endograft, which could have also been an option. The authors do well in reminding us of the almost forgotten indication for aortic fenestration, that of preventing false lumen progression. A heightened concern for associated stent-graft collapse may further be prudent when an endograft is present. This technique could prove useful in cases not suitable for proximal aortic tear coverage. There remains, however, the concern of aneurysm development with a patent false lumen.

Optimization of rifampin coating on covered Dacron endovascular stent grafts for infected aortic aneurysms

Objective: In the treatment of an infected aorta, open repair and replacement with a rifampin‐impregnated Dacron vascular graft decrease the risk of prosthetic graft infections, with several protocols available in the literature. We hypothesize that the same holds true for endovascular aneurysm repair, and after studying and optimizing rifampin solution concentration and incubation period to maximize the coating process of rifampin on Dacron endovascular stent grafts (ESGs), we propose a rapid real‐time perioperative protocol. Methods: Several prepared rifampin solutions, including a negative control solution, were used to coat multiple triplicate sets of Dacron endovascular aortic stent grafts at different but set incubation periods. Rifampin elution from the grafts was studied by spectroscopic analysis. Once an optimized solution concentration and incubation time were determined, the elution of rifampin over time from the graft and the grafts surface characteristics were studied by ultraviolet‐visible spectroscopy and atomic force microscopy. Results: All coated ESGs with any concentration of prepared rifampin solution, regardless of incubation time, immediately demonstrated a visible bright orange discoloration and subsequently after elution procedures returned to the original noncolored state. At the 25‐minute incubation time (standard flush), there was no statistical difference in the amount of rifampin coated to the ESGs with 10‐mg/mL, 30‐mg/mL, and 60‐mg/mL solutions (0.06 ± 0.01, 0.07 ± 0.05, and 0.044 ± 0.01, respectively; P > .05). This was also true for a 10‐minute incubation time (express flush) of 10‐mg/mL and 60‐mg/mL rifampin solution concentrations (0.04 ± 0.007 and 0.066 ± 0.014, respectively; P = .22). The elution‐over‐time of coated rifampin ESG, although not statistically significant, did seem to plateau and to reach a steady state by 50 hours and was confirmed by surface characteristics using atomic force microscopy. Conclusions: Having studied two variables of rifampin coating techniques to Dacron ESGs, the authors propose a rapid real‐time perioperative coating protocol by using a 10‐mg/mL rifampin solution for a 10‐minute incubation period. As rifampin loosely binds to Dacron ESGs by weak intermolecular forces, a rifampin‐coated ESG would need to be inserted in a timely fashion to treat the diseased aorta and to deliver its antibiotic affect. A rapid perioperative coating protocol followed by immediate deployment makes our proposed technique especially useful in an urgent and unstable clinical scenario. Clinical Relevance: In the treatment of an infected aorta, open repair with rifampin‐impregnated vascular grafts has been described to minimize the risk of prosthetic graft infections, with several protocols available in the literature. We hypothesize that the same holds true for endovascular aneurysm repair. After studying and optimizing several variables to maximize the coating process of rifampin on Dacron endovascular stent grafts (ESGs), we propose a standardized rapid real‐time perioperative protocol especially useful in an urgent and unstable clinical scenario. To further provide greater personalized patient care, future directions to ESG coating may include coating with a broader spectrum antibiotic (eg, piperacillin and tazobactam) as well as testing of antibiotic‐coated ESG elution properties in vivo with animal models.

Nontumescent-Based Versus Tumescent-Based Endovenous Therapies for Patients with Saphenofemoral Reflux and Varicose Veins: A Meta-Analysis

However, its use in obliterating perforating veins has not yet been examined. Here we report our series of ultrasound-guided direct cyanoacrylate injection into perforator veins for the management of chronic varicose veins. The objective of this study was to assess the clinical outcomes and complications after direct injection of cyanoacrylate-based adhesives into venous perforators. Methods: A retrospective analysis of patients undergoing varicose vein treatment with VenaSeal (Medtronic of Canada Ltd, Vancouver, BC) at Vancouver General Hospital between 2015 and 2018 was conducted. Patients were included if perforator veins were treated with direct injection of cyanoacrylate glue. Patients’ demographics, class of venous disease, and location of perforator veins were collected (Table I). Outcomes at short-term and midterm follow-up appointments were also analyzed (Table II). Results: A total of 18 patients with 19 legs and 22 perforator vein injections were included. The amount of cyanoacrylate injected per perforator was 0.2 mL. The average age of patients was 63 6 3 years, with 61% being female and a body mass index of 25 6 2 kg/m. Clinical, Etiology, Anatomy, and Pathophysiology classification and the location of perforators treated are shown in Table I. Immediate treatment success was noted in all 22 instances. Treatment success was 100% at short-term follow-up. There were three cases of superficial phlebitis noted that had resolved by midterm follow-up. There were no deep venous thromboses or other procedure-related complications noted at midterm follow-up. Conclusions: Ultrasound-guided direct perforator injection of cyanoacrylate glue is a safe and effective treatment for patients undergoing concurrent superficial vein ablation.

Distal Placement of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) to Restore Hemodynamic Stability in a Patient With Proximal Aortic Rupture

Purpose: To report unconventional use of the resuscitative endovascular balloon occlusion of the aorta (REBOA) technique to restore hemodynamic stability in a patient who was hemorrhaging from aortic injury proximal to the target zone of occlusion. Case Report: A 72-year-old woman underwent urgent thoracic stent-graft repair of a ruptured 8×8-cm mycotic pseudoaneurysm. Two months later, follow-up imaging revealed that the proximal aortic stent seal zone had degenerated, so a percutaneous procedure was performed 2 months later to preemptively reinforce the segment of stented aorta. Shortly after obtaining femoral access, the patient’s condition abruptly deteriorated with profound hypotension, presumably a result of an access complication. REBOA was established in the supraceliac aorta, which sustained the mean arterial pressure while the anesthesiologist resuscitated the patient. Unexpectedly, angiography showed a rupture of the descending thoracic aorta immediately proximal to the upper stent-graft. Balloon inflation distal to the rupture site was maintained while the patient’s hypotension was treated. Another stent-graft was quickly placed over the area of concern, overlapping proximal to the prior grafts. Once the aortic perforation was sealed, the patient stabilized hemodynamically. Inotropic support was weaned, and the REBOA occlusion catheter was deflated. Final angiograms of the arch and thoracic aorta confirmed no extravasation; angiograms of the infrarenal aorta and iliac arteries showed no evidence of injury. Conclusion: This case illustrates that applying REBOA distal to the injury site in certain clinical scenarios may sufficiently increase peripheral resistance to compensate temporarily for cardiovascular collapse secondary to aortic injury.