Alan M. Graham

Carotid artery duplex scanning in preoperative assessment for coronary artery revascularization: The association between peripheral vascular disease, carotid artery stenosis, and stroke

PURPOSE The purpose of this study was to identify high-risk populations for severe carotid artery disease (SCD) and neurologic events (NE) after nonemergency isolated coronary artery bypass graft procedures (CABG). METHODS Between February 1989 and July 1992, 387 patients underwent preoperative carotid artery duplex scanning as part of a preoperative assessment for nonemergency cardiac procedures. Of these patients, 376 had isolated CABG, and 11 had combined carotid endarterectomy (CEA) and CABG. Patient demographics, risk factors, and preoperative neurologic symptoms were recorded and analyzed. Severe carotid artery disease was defined as a 80% or greater stenosis of either internal carotid artery by carotid artery duplex scanning. Patients were evaluated for neurologic events (cerebrovascular accident, transient ischemic attack, amaurosis fugax, or reversible ischemic neurologic deficits) during the in-hospital postoperative period. RESULTS The prevalence of SCD was 8.5% (33 patients). The 33 patients with SCD were significantly older (65.6 +/- 6.5 years vs 62.5 +/- 10.4 years, p = 0.02), had previous CEA (27.3% vs 2.0%, p = 0.00001), had preoperative neurologic symptoms (21.2% vs 5.9%, p = 0.002), and had peripheral vascular disease (PVD) (63.6% vs 16.9%, p = 0.00001). The sensitivity of PVD for SCD is 63.6% (n = 21/33) (specificity 83.1%, positive predictive value 25.9%, negative predictive value 96.1%). In patients undergoing CABG alone, those who had postoperative NE were older (69.6 +/- 6.7 years vs 62.5 +/- 10.3 years, p = 0.036) and more likely to have PVD (50% vs 19.7%, p = 0.034), SCD (40% vs 4.9%, p = 0.001) and previous CEA (40% vs 2.7%, p = 0.0002). The incidence of postoperative NE in patients with SCD was 18.2% vs 1.7% in patients without SCD (p = 0.001). The sensitivity of SCD for NE was 40% (n = 4/10) (specificity 95.1%, positive predictive value 18.2%, negative predictive value 98.3%). CONCLUSIONS PVD may be helpful to identify patients at high risk for severe carotid artery stenosis. Postoperative NE in patients with CABG are associated with increasing age, carotid artery stenosis greater than 80%, previous CEA, and PVD.

Postoperative sepsis in the United States

Objectives: To evaluate the incidence of postoperative sepsis after elective procedures, to define surgical procedures with the greatest risk for developing sepsis, and to evaluate patient and hospital confounders. Background Data: The development of sepsis after elective surgical procedures imposes a significant clinical and resource utilization burden in the United States. We evaluated the development of sepsis after elective procedures in a nationally representative patient cohort and assessed the effect of sociodemographic and hospital characteristics on the development of postoperative sepsis. Methods: The Nationwide inpatient sample was queried between 2002 and 2006 and patients developing sepsis after elective procedures were identified using the patient safety indicator “Postoperative Sepsis” (PSI-13). Case-mixa djusted rates were calculated by using a multivariate logistic regression model for sepsis risk and an indirect standardization method. Results: A total of 6,512,921 weighted elective surgical cases met the inclusion criteria and 78,669 cases (1.21%) developed postoperative sepsis. Case-mix adjustment for age, race, gender, hospital bed size, hospital location, hospital teaching status, and patient income demonstrated esophageal, pancreatic, and gastric procedures represented the greatest risk for the development of postoperative sepsis. Thoracic, adrenal, and hepatic operations accounted for the greatest mortality rates if sepsis developed. Increasing age, Blacks, Hispanics, and men were more likely to develop sepsis. Decreased median household income, larger hospital bed size, urban hospital location, and nonteaching status were associated with greater rates of postoperative sepsis. Conclusions: The development of postoperative sepsis is multifactorial and procedures, most likely to develop sepsis, did not demonstrate the greatest mortality after sepsis developed. Factors associated with the development of sepsis included race, age, hospital size, hospital location, and patient income. Further evaluation of high-risk procedures, populations, and environments may assist in reducing this costly complication.

Integrins are required for the differentiation of visceral endoderm.

Integrins of the β1 subfamily are highly expressed in the early mouse embryo and are essential for the formation of primitive germ layers from the inner cell mass (ICM). We investigated the mechanisms by which αβ1 integrins regulate ICM morphogenesis by using the embryonic-stem-cell-derived embryoid body (EB), a model for peri-implantation development. Ablation of integrin β1 in EBs resulted in endoderm detachment and in maturation defects, which were manifested by the mislocalization of GATA4 in the cytoplasm and the markedly reduced synthesis of basement membrane (BM) components and the lineage marker disabled homolog 2. The mutant endoderm cells failed to spread on BM substrates, but could spread on vitronectin, which induced upregulation of αvβ3 integrin and integrin-dependent GATA4 nuclear translocation. Forced expression of integrin β3 in the mutant EBs completely rescued endoderm morphogenesis, suggesting that integrin β3 can substitute for integrin β1 in the endoderm. Furthermore, the mitogen-activated protein kinases (MAPKs) ERK1 and ERK2 (ERK1/2) and p38 were activated in endoderm in an integrin-dependent fashion. Pharmacological inhibition of ERK1/2 or p38 MAPK blocked vitronectin-induced GATA4 nuclear translocation and endoderm maturation, whereas expression of a constitutively active ERK kinase (MEK1) or p38 MAPK in the mutant cells rescued endoderm maturation in integrin-β1-null endoderm cells. Collectively, these results suggest that integrins are required for both the stable adhesion and maturation of visceral endoderm, the latter being mediated through the activation of ERK1/2 and p38 MAPK.

Infectious complications after elective vascular surgical procedures

OBJECTIVE This study was conducted to evaluate and compare the rates of postoperative infectious complications and death after elective vascular surgery, define vascular procedures with the greatest risk of developing nosocomial infections, and assess the effect of infection on health care resource utilization. METHODS The Nationwide Inpatient Sample (2002-2006) was used to identify major vascular procedures by International Classification of Diseases, 9th Clinical Modification (ICD-9-CM) codes. Infectious complications identified included pneumonia, urinary tract infections (UTI), postoperative sepsis, and surgical site infections (SSI). Case-mix-adjusted rates were calculated using a multivariate logistic regression model for infectious complication or death as an outcome and indirect standardization. RESULTS A total of 870,778 elective vascular surgical procedures were estimated and evaluated with an overall postoperative infection rate of 3.70%. Open abdominal aortic surgery had the greatest rate of postoperative infections, followed by open thoracic procedures and aorta-iliac-femoral bypass. Thoracic endovascular aneurysm repair (TEVAR) infectious complication rates were two times greater than after EVAR (P < .0001). Pneumonia was the most common infectious complication after open aortic surgery (6.63%). UTI was the most common after TEVAR (2.86%) and EVAR (1.31%). Infectious complications were greater in octogenarians (P < .0002), women (P < .0001), and blacks (P < .0001 vs whites and Hispanics). Nosocomial infections after elective vascular surgery significantly increased hospital length of stay (13.8 +/- 15.4 vs 3.5 +/- 4.2 days; P < .001) and reported total hospital cost (

Antibacterial activity, antibiotic retention, and infection resistance of a rifampin-impregnated gelatin-sealed Dacron graft

37,834 +/-

Antiphospholipid antibodies lead to increased risk in cardiovascular surgery

42,905 vs

Endovascular management of ureteroarterial fistula

11,851 +/-

In-hospital and 30-day outcomes after tibioperoneal interventions in the US Medicare population with critical limb ischemia

11,816; P < .001). CONCLUSIONS Elective vascular surgical procedures vary widely in the estimated risk of postoperative infection. Open aortic surgery and endarterectomy of the head and neck vessels have, respectively, the greatest and the lowest reported incidence for postoperative infectious complications. Women, octogenarians, and blacks have the highest risk of infectious complications after elective vascular surgery. Disparities in the development of infectious complications on a systems level were also found in larger hospitals and teaching hospitals. Hospital infectious complications were found to significantly increase health care resource utilization. Strategies that reduce nosocomial complications and target high-risk procedures may offer significant future cost savings.

Endovascular versus open repair of popliteal artery aneurysms: outcomes in the US Medicare population.

PURPOSE A gelatin-sealed porous Dacron graft impregnated with rifampin was evaluated in a two-part study of its use in preventing prosthetic infection. METHODS The graft was impregnated by soaking it for 15 minutes in rifampin (1 mg/ml). In part 1 its antibacterial activity and rifampin retention over time were determined. Infrarenal aortic replacement was performed in pigs, and the rifampin concentration of the graft, serum, and perigraft space was assayed up to 96 hours after surgery. In part 2, infection resistance was tested in pigs in which the retroperitoneum was contaminated with Staphylococcus aureus after graft replacement. The postoperative infection rate was compared in three groups: pigs given gelatin-sealed grafts without rifampin (controls), pigs receiving nonimpregnated grafts and intravenous rifampin (15 mg/kg) for 3 days after surgery, and those given the rifampin grafts. RESULTS Rifampin was present in the grafts for up to 72 hours after surgery and in the perigraft fluid for 24 hours but was never detected in the serum. The grafts had inhibitory activity in vitro against S. aureus and the biofilm phase of Staphylococcus epidermidis for up to 3 days and against Escherichia coli for 2 days. Pigs given intravenous rifampin had a significantly lower infection rate than had control pigs (7/12 vs 13/13; p = 0.02); those receiving the rifampin graft had a lower rate (2/13) than had either the control pigs (p < 0.001) or those given intravenous rifampin (p < 0.04). CONCLUSIONS This simple method of graft impregnation resulted in antibiotic retention for 3 days and appeared to be superior to intravenous antibiotic administration in preventing perioperative graft infection.

CREG promotes a mature smooth muscle cell phenotype and reduces neointimal formation in balloon-injured rat carotid artery

BACKGROUND Antiphospholipid (APL) antibodies are a heterogenous group of antibodies that have been associated with an increase in bleeding complications and a marked increase in thrombotic events, both of which result in significant patient morbidity and mortality. PATIENTS AND METHODS A retrospective analysis of patients identified to be positive for APL via a university thrombosis registry who had cardiovascular surgery between 1989 and 1994. RESULTS Seventy-one patients positive for APL antibodies were identified. Of those patients, 19 had cardiovascular surgical procedures (11 women and 8 men, mean age 58.4 years, range 38 to 78). A total of 48 cardiovascular surgical procedures (mean 2.5 procedures/patient) were performed in the 19 patients. These procedures included 13 lower-extremity reconstructions, 11 upper-extremity reconstructions/fistulas, 8 cardiac valve replacements, 5 coronary artery bypass procedures, 5 major amputations, 4 infrarenal aortic reconstructions, and 2 carotid endarterectomies. Sixteen of the 19 patients (84.2%) suffered major postoperative complications. These included 16 thrombosed grafts, 5 strokes, 5 major bleeding events, 2 pulmonary emboli, and 2 myocardial infarctions. Ultimately, 12 of the 19 patients (63.2%) died of complications related to surgery. CONCLUSIONS This series of patients confirms that patients with circulating APL antibodies are prone to excessive postoperative morbidity and mortality after cardiovascular surgical procedures. The presence of APL antibodies may be a maker of increased risk of complications after cardiovascular surgery.