Postoperative Infections are Associated with Increased Risk of Cardiac Events in Vascular Patients.

BACKGROUND: Despite advances in perioperative care, the rate of cardiac events in vascular patients remains high. We have previously shown that infections in trauma patients are associated with higher rates of subsequent cardiac complications, likely due to the additive effect of a second hit of an infection following the trauma. The aim of this study was to investigate whether there is an association between postoperative infections and subsequent cardiac events in vascular patients. METHODS: A 5-year retrospective review of demographics, comorbidities, operative interventions, infectious, and cardiac events in all vascular patients who underwent an operative intervention at a single tertiary referral center was performed. In patients with clinical suspicion of myocardial injury, myocardial damage was defined as troponin >0.15 ng/mL and myocardial infarction (MI) as troponin >1 ng/mL. Pneumonia was diagnosed using bronchoalveolar lavage (BAL) and considered positive if BAL fluid culture contained >10,000 colony-forming units (cfu). Urinary tract infection (UTI) was diagnosed if the urine culture contained >100,000 cfu. All other infections were diagnosed by culture data. Regression analysis was performed to assess risk of cardiac events as a function of infections adjusting for age, gender, and comorbidities. RESULTS: We analyzed 1,835 vascular operative interventions with the mean age of the cohort 65.5 years (65.9% male). The overall infection rate was 13.2%, with UTI being the most common (60.3%). The overall rate of myocardial damage was 8.1% and the rate of MI 3.8%. Rates of both myocardial damage (15.5 vs. 7.7%; P = 0.0015) and MI (7.1 vs. 3.4%; P = 0.018) were significantly higher in patients with infections, compared to those without infections. Adjusting for age, gender, medical comorbidities, open versus endovascular cases as well as statin and steroid use, patients with UTI were more likely to subsequently develop either myocardial damage (odds ratio [OR] = 3.57 [95% confidence interval = 1.51-8.45]) or MI (OR = 4.20 [1.23-14.3]). A similar association was noted between any infections and either myocardial damage (OR = 2.97 [1.32-6.65]) or MI (OR = 4.31 [1.44-12.94]). CONCLUSIONS: We herein describe an association between postoperative infections, most commonly UTI, and subsequent cardiac events. Efforts should be made to minimize the risk of developing infections to ensure cardioprotection in vascular patients during perioperative period.

Open revascularization procedures are more likely to influence smoking reduction than percutaneous procedures.

BACKGROUND: Among patients with peripheral arterial disease (PAD), smokers have a higher incidence of life- and limb-threatening complications, including lower extremity ischemic rest pain, myocardial infarction, and cardiac death, highlighting the need for smoking reduction. Several studies have previously investigated the perioperative period as a teachable moment for smoking cessation. The purpose of this study is to determine whether the type of revascularization for PAD (percutaneous versus open) is associated with smoking reduction. METHODS: Study participants included patients seen at a tertiary academic medical center in Providence, RI, between 2005 and 2010 and assigned International Classification of Diseases, Ninth Revision code diagnoses indicative of PAD. This study uses patient-answered surveys and retrospective chart review to assess changes in smoking habits after medical, percutaneous, or open revascularization. Surveys also assessed patient perceptions regarding the influence of intervention on smoking reduction and how strongly patients associate PAD with their smoking habits. RESULTS: Of 54 patients who were active smokers at the time of intervention, 8 (67%) in the medical management group, 12 (50%) in the percutaneous group, and 15 (83%) in the open intervention group reduced smoking by 50% after intervention. After controlling for several confounders, open revascularization was independently associated with smoking reduction when compared with percutaneous intervention (odds ratio, 8.26; 95% confidence interval, 1.18, 76.7; P = 0.043). Surveys revealed that 94% of the patients believed that smoking was a significant contributor to their PAD. CONCLUSIONS: Patients with PAD who undergo open revascularization are more likely to reduce smoking than those who undergo percutaneous revascularization. The perioperative period provides an opportunity to improve rates of smoking reduction.

A 14-year experience with blunt thoracic aortic injury.

OBJECTIVE: This study reviewed the natural history of blunt thoracic aortic trauma (BTAT) over a 14-year period at our level 1 trauma center and compared open vs endovascular treatment. METHODS: All patients with BTAT presenting to a level 1 trauma center from 1998 to 2011 were included in a retrospective analysis. Multiple data points and short-term and midterm outcomes were ascertained through a retrospective record review. RESULTS: We identified 129 patients with BTAT. Of these, 32 (25%) were dead on arrival, 38 (29%) underwent a resuscitative thoracotomy and died, 33 (26%) underwent open repair, 14 (11%) underwent endovascular repair, 9 (7%) underwent simultaneous procedures, and 3 (2%) were managed nonoperatively. Mean Injury Severity Scores and Revised Trauma Scores were similar (P = .484, P = .551) between the open repair group (n = 36) and the endovascular repair group (n = 14). In the open repair group, there were 14 deaths (42%) ≤ 30 days of injury, 3 strokes (9%), 2 patients (6%) with paralysis, 2 myocardial infarctions (MIs; 6%), and 3 patients (9%) who required hemodialysis. In the endovascular group, there was 1 death (7%) ≤ 30 days of injury, 1 (7%) stroke, and 1 (7%) stent collapse. No paralysis, MI, or renal failure requiring hemodialysis was noted in the endovascular group. The average length of stay was 15 days for patients treated with endovascular repair vs 24 days for those treated with open repair (P = .003). CONCLUSIONS: The incidence of BTAT is low but the mortality associated with it is significant. During the 14-year period studied, there was a clear change in management preference from open repair to endovascular repair at our level 1 trauma center. Outcomes, including stroke, MI, renal failure, paralysis, length of stay, and death, appear to be reduced in the endovascular group.

Predictors of shunt during carotid endarterectomy with routine electroencephalography monitoring.

BACKGROUND: The routine use of intraoperative electroencephalography (EEG) monitoring with selective shunt placement during carotid endarterectomy (CEA) has been shown to be safe and effective. We attempt to identify the anatomic and clinical factors associated with significant EEG changes requiring shunt placement during CEA. METHODS: Between January 2005 and June 2007, 242 CEAs were performed with selective shunt placement for significant EEG changes. Risk factors assessed include severity of both ipsilateral and contralateral disease, presence of ipsilateral preoperative symptoms, hypertension, coronary artery disease, diabetes, age, gender, and preemptive intraoperative blood pressure manipulation to >or=20% above baseline before cross-clamping. Data were analyzed with the chi(2) test (P < .05 was significant). RESULTS: CEA was performed for asymptomatic disease in 177 of 242 patients (73.1%). The perioperative stroke rate was 0.8% (2 of 242), and the overall morbidity rate was 4.5%. No patients died. Significant EEG changes requiring shunt occurred in 35 patients (14.46%). Factors associated with carotid shunt placement were moderate ipsilateral carotid artery stenosis (50% to 79%) compared with severe (>or=80%) disease (30.6% vs 11.7%, P = .003) and degree of contralateral carotid stenosis (0% to 49%, 10.8%; 50% to 79%, 10.9%; 80% to 99%, 23.2%; occlusion, 50%; P = .0003). Presence of symptoms, gender, age, hypertension, diabetes, or coronary artery disease, and preemptive intraoperative manipulation of blood pressure were not significant predictors of shunt placement. CONCLUSION: CEA performed with routine EEG monitoring and selective shunt placement is associated with a low risk of perioperative stroke. Identified predictors of significant EEG changes were anatomic factors including degree of contralateral carotid artery disease and moderate ipsilateral carotid artery stenosis (50% to 79%). Although contralateral carotid occlusion has been accepted as indication for shunt placement in the absence of cerebral monitoring, this study suggests that high-grade contralateral disease and moderate ipsilateral carotid stenosis are associated with cerebral ischemia resulting in EEG changes and should prompt consideration for nonselective shunting.

The effects of vasoactive agents on flow through saphenous vein grafts during lower-extremity peripheral vascular surgery.

PURPOSE: The purpose of this study was to assess the effects of hemodynamic alterations on vein graft flow during peripheral vascular surgery. It was hypothesized that vasopressors can be administered without compromising flow through the vein grafts. SETTING: Tertiary care center, university medical center. STUDY DESIGN: Randomized placebo-controlled double-blinded study. METHODS: The effects of phenylephrine, epinephrine, milrinone, intravenous fluid, and placebo on newly constructed peripheral vein grafts were assessed in 60 patients (12 patients in each of 5 groups). Systemic and central hemodynamics were measured by using intra-arterial and pulmonary artery catheters. Vein graft flow was measured by using a transultrasonic flow probe (Transultrasonic Inc, Ithaca, NY). RESULTS: Phenylephrine increased systemic mean blood pressure (mBP) (68.2-94.0 mmHg, p < 0.01), systemic vascular resistance (SVR) (1,091-1,696 dynes x sec x cm(-5), p < 0.001), and vein graft flow (39.5-58.9 mL/min, p < 0.01), whereas cardiac output remained unchanged. Epinephrine resulted in increased cardiac output (4.4-6.9 L/min, p < 0.01) and mBP (72.7-89.1 mmHg, p < 0.01), whereas vein graft flow was reduced in 6 of 12 patients. Intravenous fluid administration resulted in a relatively smaller increase in graft flow (37.6-46.0 mL/min, p < 0.05), an increase in cardiac output, and an insignificant decrease in SVR. Other treatments had either little or no effect on vein graft flow. CONCLUSION: The study hypothesis was partly supported. Although both phenylephrine and epinephrine increased blood pressure, only the former increased vein graft flow in all patients. In conjunction with increases in graft flow after fluid administration, these data suggest that factors affecting vein graft flow are not just simply related to systemic hemodynamics.

Aortoiliac insufficiency: long-term experience with stent placement for treatment.

PURPOSE: To establish and report the authors' experience with the long-term outcomes of aortoiliac stent placement for treatment of chronic lower-extremity ischemia. MATERIALS AND METHODS: Stents were placed in 505 arterial segment lesions in 365 patients who presented with symptoms of chronic leg ischemia between February 1992 and March 2001. The 505 treated lesions were 88 occlusions and 417 stenoses. Indications for stent placement were claudication in 312 (62%), rest pain in 107 (21%), ulcer in 67 (13%), and gangrene in 19 (4%) arterial segments. Patients were followed up for up to 105 months (mean, 33 months +/- 27 [SD]). RESULTS: Hemodynamic success was achieved in 484 (98%) of the 496 limbs for which postprocedural translesion pressure gradients were available. Mean ankle-brachial indexes improved from 0.53 +/- 0.25 to 0.79 +/- 0.23 (P <.001). Major complications were seen in 24 (7%) patients. Two patients (0.5%) died within 30 days after stent placement. Twenty (6%) of 355 patients underwent aortic or iliac bypass surgery during the follow-up period. Eight years after stent placement, primary patency was 74%; primary assisted patency, 81%; and secondary patency, 84%. Variables associated with better patency included stenosis (rather than occlusion), shorter lesion length, older age, and limb-threatening ischemia. At the last follow-up examination, 74% of the 466 limbs for which follow-up clinical status data were available were asymptomatic, 22% were associated with claudication, 3% were associated with rest pain, and 1% were associated with ischemic tissue loss. Five patients underwent amputation on the ipsilateral side after stent placement. CONCLUSION: Findings from long-term experience with aortoiliac stent placement for treatment of chronic lower-extremity ischemia confirmed the procedure to be a durable, low-risk revascularization option.