Risk factors for postoperative sepsis in laparoscopic gastric bypass

Introduction

Postoperative sepsis is a rare but serious complication following elective surgery. The purpose of this study was to identify the rate of postoperative sepsis following elective laparoscopic gastric bypass (LGBP) and to identify patients’ modifiable, preoperative risk factors.

Methods

The American College of Surgeons National Surgical Quality Improvement Program database was queried from 2005 to 2013 for factors associated with the development of postoperative sepsis following elective LGBP. Patients who developed sepsis were compared to those who did not. Results were analyzed using the Chi-square test for categorical variables and Wilcoxon two-sample test for continuous variables. A multivariate logistic regression analysis was utilized to calculate adjusted odds ratios for factors contributing to sepsis.

Results

During the study period, 66,838 patients underwent LGBP. Of those, 546 patients developed postoperative sepsis (0.82 %). The development of sepsis was associated with increased operative time (161 ± 77.8 vs. 135.10 ± 56.5 min; p < 0.0001) and a greater number of preoperative comorbidities, including diabetes (39.6 vs. 30.6 %; p < 0.0001), hypertension requiring medication (65.2 vs. 54 %; p < 0.0001), current tobacco use (16.7 vs. 11.5 %; p = 0.0002), and increased pack-year history of smoking (8.6 ± 18.3 vs. 5.6 ± 14.2; p = 0.0006), and the Charlson Comorbidity Index (0.51 ± 0.74 vs. 0.35 ± 0.57, p < 0.0001). Sepsis resulted in an increased length of stay (10.1 ± 14.4 vs. 2.4 ± 4.8 days; p < 0.0001) and a 30 times greater chance of 30-day mortality (4.03 vs. 0.11 %, p < 0.0001). Multivariate logistic regression analysis showed that current smokers had a 63 % greater chance of developing sepsis compared to non-smokers, controlling for age, race, gender, BMI, and CCI score (OR 1.63, 95 % CI 1.23–2.14; p = 0.0006).

Conclusions

Laparoscopic gastric bypass is uncommonly associated with postoperative sepsis. When it occurs, it portends a 30 times increased risk of death. A patient history of diabetes, hypertension, and increasing pack-years of smoking portend an increased risk of sepsis. Current smoking status, a preoperative modifiable risk factor, is independently associated with the chance of postoperative sepsis. Preoperative patient optimization and risk reduction should be a priority for elective surgery, and patients should be encouraged to stop smoking prior to gastric bypass.

     

Topical mitomycin-C for recalcitrant esophageal strictures: a novel endoscopic/fluoroscopic technique for safe endoluminal delivery

Background

Nonsurgical treatment of recalcitrant pediatric esophageal strictures is challenging. The chemotherapy drug mitomycin-C, which reduces collagen synthesis and scar formation, shows anecdotal promise in the topical treatment of these strictures. Mitomycin-C is cytotoxic, and a safe endoluminal delivery system that avoids inadvertent application to adjacent mucosa has not yet been described.

Discussion

We have treated 2 patients with a combined endoscopic/fluoroscopic technique that ensures protected delivery of a mitomycin-soaked pledget directly to the targeted site.Following pneumatic balloon dilation of the stricture under fluoroscopy, flexible esophagoscopy is performed to the disrupted stricture. Through the gastrostomy tract, a 12F to 16F semirigid sheath is introduced over a guide wire and passed retrograde up the esophagus to the stricture. A grasping forceps introduced through the instrument channel of the esophagoscope is advanced through the sheath and grasps a mitomycin-C-soaked pledget. The pledget is drawn back through the sheath up to the stricture where timed, serial radial applications to the stricture are performed without any contamination of the rest of the esophagus or stomach.

Conclusion

We describe a novel technique of endoluminal delivery and focused application of mitomycin-C to an esophageal stricture that avoids inadvertent topical application to adjacent mucosa.     

Thyroid-stimulating hormone, thyroid hormones, and bone loss

It has become accepted by virtue of rich anecdotal experience and clinical research that thyrotoxicosis is associated with high-turnover osteoporosis. The bone loss, primarily due to accelerated resorption that is not compensated by a coupled increase in bone formation, has been attributed solely to elevated thyroid hormone levels. Evidence using mice lacking the thyroid hormone receptors α and β establishes a role for thyroid hormones in regulating bone remodeling but does not exclude an independent action of thyroid-stimulating hormone (TSH), levels of which are low in hyperthyroid states, even when thyroid hormones are normal, as after thyroxine supplementation and in subclinical hyperthyroidism. We show that TSH directly suppresses bone remodeling and that TSH receptor null mice have profound bone loss, suggesting that reduced TSH signaling contributes to hyperthyroid osteoporosis. TSH and its receptor could become valuable drug targets in treating bone loss.     

Safety and performance evaluation of a next‐generation antimicrobial dressing in patients with chronic venous leg ulcers

The objective of this study was to investigate the safety and performance of AQUACEL? Ag+ dressing, a wound dressing containing a combination of anti‐biofilm and antimicrobial agents, in the management of chronic wounds. Patients (n = 42) with venous leg ulcers exhibiting signs of clinical infection were treated for 4 weeks with AQUACEL? Ag+ dressing, followed by management with AQUACEL? wound dressings for 4 weeks. Wound progression, wound size, ulcer pain and clinical evolution of the wound were assessed for up to 8 weeks. Adverse events were recorded throughout the study. AQUACEL? Ag+ dressing had an acceptable safety profile, with only one patient discontinuing from the study, because of a non‐treatment‐related adverse event. After 8 weeks, substantial wound improvements were observed: 5 patients (11·9%) had healed ulcers and 32 patients (76·2%) showed improvement in ulcer condition. The mean ulcer size had reduced by 54·5%. Patients reported less pain as the study progressed. Notable improvements were observed in patients with ulcers that were considered to require treatment with systemic antibiotics or topical antimicrobials at baseline (n = 10), with a mean 70·2% reduction in wound area. These data indicate that AQUACEL? Ag+ dressing has an acceptable safety profile in the management of venous leg ulcers that may be impeded by biofilm.     

Alterations in T-Cell Subset Frequency in Peripheral Blood in Obesity

Background: Obesity affects the regulation of immune and inflammatory responses. This study characterizes differences in peripheral blood lymphocyte phenotype in obese humans. Methods: Frequencies of lymphocyte subsets among peripheral blood mononuclear cells were compared between 10 obese (BMI ≥35) and 10 lean subjects, as determined by antibodies directed against cluster differentiation (CD) markers. Results: Obese patients demonstrated an increased frequency of CD3+CD4+ T-cells (mean difference 12%, P=0.004), a decreased frequency of CD3+CD8+ T-cells (mean difference 9.4%, P=0.016) and an increased frequency of CD3+CD8+CD95+ T-cells (mean difference 13.3%, P=0.032). No other differences among T-cell or monocyte subsets were noted. Conclusions: Obesity is associated with alterations in frequencies of peripheral CD4+ and CD8+ T-cells and aberrations in the expression of CD95 among CD8+ T-cells. These data suggest both CD4+ and CD8+ T-cell compartments, as well as the regulation of CD95 expression on CD8+ T-cells, as targets for further study into obesity's effects on the immune system.     

Cannabinoids: is there a potential treatment role in epilepsy?

Cannabinoids have been used medicinally for centuries, and in the last decade, attention has focused on their broad therapeutic potential particularly in seizure management. While some cannabinoids have demonstrated anticonvulsant activity in experimental studies, their efficacy for managing clinical seizures has not been fully established. This commentary will touch on our understanding of the brain endocannabinoid system’s regulation of synaptic transmission in both physiological and pathophysiological conditions, and review the findings from both experimental and clinical studies on the effectiveness of cannabinoids to suppress epileptic seizures. At present, there is preliminary evidence that non-psychoactive cannabinoids may be useful as anticonvulsants, but additional clinical trials are needed to fully evaluate the efficacy and safety of these compounds for the treatment of epilepsy.     

X-linked chronic granulomatous disease: correction of NADPH oxidase defect by retrovirus-mediated expression of gp91-phox

Chronic granulomatous disease (CGD) is an inherited immunodeficiency resulting from the inability of an individual's phagocytes to produce superoxide anions because of defective NADPH oxidase. The disease may be treated by bone marrow transplantation and as such is a candidate for somatic gene therapy. Two thirds of patients have defects in an X- linked gene (X-CGD) encoding gp91-phox, the large subunit of the membrane cytochrome b-245 component of NADPH oxidase. Epstein-Barr virus-transformed B-cell lines from patients with CGD provide a model system for the disease. We have used retrovirus-mediated expression of gp91-phox to reconstitute functionally NADPH oxidase activity in B-cell lines from three unrelated patients with X-CGD. The protein is glycosylated and membrane associated, and the reconstituted oxidase is appropriately activated via protein kinase C. The kinetics of superoxide production by such reconstituted cells is similar to that of normal B-cell lines. These data show the potential of gene therapy for this disease.