Laminar flow reduces cases of surgical site infections in vascular patients

Introduction

Numerous strategies are employed routinely in an effort to lower rates of surgical site infections (SSIs). A laminar flow theatre environment is generally used during orthopaedic surgery to reduce rates of SSIs. Its role in vascular surgery, especially when arterial bypass grafts are used, is unknown.

Methods

A retrospective review of a prospectively maintained database was undertaken for all vascular procedures performed by a single consultant over a one-year period. Cases were performed, via random allocation, in either a laminar or non-laminar flow theatre environment. Demographic data, operative data and evidence of postoperative SSIs were noted. A separate subgroup analysis was undertaken for patients requiring an arterial bypass graft. Univariate and multivariate logistical regression was undertaken to identify significant factors associated with SSIs.

Results

Overall, 170 procedures were analysed. Presence of a groin incision, insertion of an arterial graft and a non-laminar flow theatre were shown to be predictive of SSIs in this cohort. In the subgroup receiving arterial grafts, only a non-laminar flow theatre environment was shown to be predictive of an SSI.

Conclusions

This study suggests that laminar flow may reduce incidences of SSI, especially in the subgroup of patients receiving arterial grafts.     

Nucleotide metabolic mismatches in mammalian hearts: implications for transplantation

Introduction

Human donor organ shortages have led surgeons and scientists to explore the use of animals as alternative organ sources. Acute thrombovascular rejection (AVR) is the main hurdle in xenotransplantation. Disparities in nucleotide metabolism in the vessels of different species may contribute significantly to the microvascular component of AVR.

Methods

We evaluated the extent of nucleotide metabolism mismatch in selected organs and endothelial cells of different mammals with particular focus on the changes in activity of ecto-5’-nucleotidase (E5’N) elicited by exposure of porcine hearts or endothelial cells to human blood (ex vivo) or human plasma (in vitro).

Results

E5’N activity in the rat heart was significantly higher than in other species. We noted a significant difference (p<0.001) in E5’N activity between human and pig endothelial cell lines. Initial pig aortic endothelial E5’N activity decreased in vitro after a three-hour exposure to human and porcine plasma while remaining constant in controls. Ex vivo perfusion with fresh human blood for four hours resulted in a significant decrease of E5’N activity in both wild type and transgenic pig hearts overexpressing human decay accelerating factor (p<0.001).

Conclusions

This study provides evidence that mismatches in basal mammalian metabolic pathways and humoral immunity interact in a xenogeneic environment. Understanding the role of nucleotide metabolism and signalling in xenotransplantation may identify new targets for genetic modifications and may lead to the development of new therapies extending graft survival.     

Trachea-innominate artery fistula: retrospective comparison of treatment methods

A fistula between the trachea and the innominate artery, a potentially fatal complication of tracheostomy, can be managed successfully. We have derived several guidelines from our experience with one such case and from a review of the 36 cases reported in the literature over the last decade. Diagnosis must be established before exsanguination occurs. Bronchoscopy and angiography are often nondiagnostic. Control of hemorrhage and a patent airway are the initial goals of treatment. Interruption of the innominate artery is the definitive treatment, with a low rebleeding rate (7%, 1/14 cases) and good long-term survival (64%, 9/14 cases). Maintenance of continuity of the innominate artery is contraindicated, because of a high rebleeding rate (60%, 6/10 cases) and poor long-term survival (10%, 1/10 cases). There is no convincing evidence that interruption of the innominate artery causes significant neurologic or vascular compromise.     

Vesicoureteral reflux: current trends in diagnosis, screening, and treatment

Context

Vesicoureteral reflux (VUR) is present in approximately 1% of children in North America and Europe and is associated with an increased risk of pyelonephritis and renal scarring. Despite its prevalence and potential morbidity, however, many aspects of VUR management are controversial.

Objective

Review the evidence surrounding current controversies in VUR diagnosis, screening, and treatment.

Evidence acquisition

A systematic review was performed of Medline, Embase, Prospero, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, clinicaltrials.gov, and the most recent guidelines of relevant medical specialty organizations.

Evidence synthesis

We objectively assessed and summarized the published data, focusing on recent areas of controversy relating to VUR screening, diagnosis, and treatment.

Conclusions

The evidence base for many current management patterns in VUR is limited. Areas that could significantly benefit from additional future research include improved identification of children who are at risk for VUR-related renal morbidity, improved stratification tools for determining which children would benefit most from which VUR treatment option, and improved reporting of long-term outcomes of VUR treatments.     

Effect of octreotide on refractory AIDS-associated diarrhea. A prospective, multicenter clinical trial

OBJECTIVE: To determine the efficacy and safety of octreotide for treatment of refractory, profuse diarrhea in patients with the acquired immunodeficiency syndrome (AIDS). DESIGN: A prospective, open-label study. SETTING: Inpatient metabolic units of four university medical centers. PATIENTS: Fifty-one patients infected with human immunodeficiency virus (HIV) who had uncontrolled diarrhea (greater than or equal to 500-mL liquid stool per day) despite treatment with maximally tolerable doses of antidiarrheal medications. INTERVENTION: After initial baseline studies, patients received octreotide, 50 micrograms every 8 hours for 48 hours. If stool volume was not reduced to less than 250 mL/d, the dose of octreotide was increased stepwise to 100, 250, and 500 micrograms. MAIN RESULTS: Fifty men and one woman (mean age, 36.3 +/- 1.1 years) entered and completed the 28-day protocol (14 days of inpatient therapy and 14 days of outpatient therapy). Stool frequency and volume decreased significantly (6.5 +/- 0.5 stools per day on day 0 compared with 3.8 +/- 0.3 stools per day on day 21 [P less than 0.001] and 1604 +/- 180 mL/d on day 0 compared with 1084 +/- 162 mL/d on day 14 [P less than 0.001], respectively). Twenty-one patients (41.2%) were considered to be partial or complete responders (reduction in daily stool volume by greater than or equal to 50% of initial collections or reduction to less than or equal to 250 mL/d). Of the 21 responders, 14 (67%) had no identifiable pathogens at initial screening compared with 9 of 30 (30%) nonresponders (P less than 0.01). CONCLUSION: Patients with AIDS-associated refractory watery diarrhea, especially those without identifiable pathogens, may respond favorably to subcutaneously administered octreotide. This drug deserves further study in a randomized, placebo-controlled trial.     

The Faith,Activity, and Nutrition (FAN) Program: Design of a participatory research intervention to increase physical activity and improve dietary habits in African American churches

BackgroundAfrican Americans are at increased risk for cardiovascular disease and cancer morbidity and mortality. Physical activity and healthy dietary practices can reduce this risk. The church is a promising setting to address health disparities, and community-based participatory research is a preferred approach.ObjectivesUsing a community-based participatory approach and the social ecologic model, the FAN trial aims to increase self-reported moderate-intensity physical activity and fruit and vegetable consumption and reduce blood pressure in African American church members. Secondary aims are to increase objectively measured moderate-intensity physical activity and fiber/whole grain consumption and reduce fat consumption.DesignFAN is a group randomized trial (GRT) with two levels of clustering: participants (N = 1279; n = 316 accelerometer subgroup) within church and church within church cluster. In the first wave, seven clusters including 23 churches were randomized to an immediate intervention or delayed intervention. In subsequent waves, 51 churches were randomized to an immediate or delayed intervention.MethodsChurch committee members, pastors, and cooks participate in full-day trainings to learn how to implement physical activity and dietary changes in the church. Monthly mailings and technical assistance calls are delivered over the 15-month intervention. Members complete measurements at baseline and 15 months. A detailed process evaluation is included.SummaryFAN focuses on modifying the social, cultural, and policy environment in a faith-based setting. The use of a community-based participatory research approach, engagement of church leaders, inclusion of a detailed process evaluation, and a formal plan for sustainability and dissemination make FAN unique.