Pharmacological Stimulation of the Cholinergic Antiinflammatory Pathway

Efferent activity in the vagus nerve can prevent endotoxin-induced shock by attenuating tumor necrosis factor (TNF) synthesis. Termed the “cholinergic antiinflammatory pathway,” inhibition of TNF synthesis is dependent on nicotinic α-bungarotoxin-sensitive acetylcholine receptors on macrophages. Vagus nerve firing is also stimulated by CNI-1493, a tetravalent guanylhydrazone molecule that inhibits systemic inflammation. Here, we studied the effects of pharmacological and electrical stimulation of the intact vagus nerve in adult male Lewis rats subjected to endotoxin-induced shock to determine whether intact vagus nerve signaling is required for the antiinflammatory action of CNI-1493. CNI-1493 administered via the intracerebroventricular route was 100,000-fold more effective in suppressing endotoxin-induced TNF release and shock as compared with intravenous dosing. Surgical or chemical vagotomy rendered animals sensitive to TNF release and shock, despite treatment with CNI-1493, indicating that an intact cholinergic antiinflammatory pathway is required for antiinflammatory efficacy in vivo. Electrical stimulation of either the right or left intact vagus nerve conferred significant protection against endotoxin-induced shock, and specifically attenuated serum and myocardial TNF, but not pulmonary TNF synthesis, as compared with sham-operated animals. Together, these results indicate that stimulation of the cholinergic antiinflammatory pathway by either pharmacological or electrical methods can attenuate the systemic inflammatory response to endotoxin-induced shock

Endovascular rescue of long-term vascular graft implants and need for continuous surveillance

We present two cases of vascular graft degradation after long-term implantation. In both patients, endovascular techniques were employed to effect continued graft patency and function. Furthermore, these cases lend further credence to the doctrine of lifelong surveillance of all vascular interventions regardless of graft material. Postoperative surveillance of vascular interventions is generally recommended to avoid failures by identifying “the failing graft”1 at the earliest possible time to facilitate corrective procedures. There is a tendency that with continued function, over time, surveillance methods are spread farther apart and in fact often discontinued. Recent experiences with two cases illustrate the vital importance of lifelong continuous surveillance regardless of the site, graft material, or absence of symptoms. Clearly, the patient's compliance is essential. Both patients consented to the publication of their cases

Thoracoscopy in acquired immunodeficiency syndrome

AbstractObjective: The role of thoracic surgery in patients with acquired immunodeficiency syndrome (AIDS) continues to evolve. This review seeks to evaluate the outcome, morbidity, and mortality associated with videoassisted thoracoscopic surgery for empyema and pneumothorax in patients with AIDS. Methods: A retrospective review was conducted of patients with AIDS in whom video-assisted thoracoscopic surgery was performed for empyema (group 1) or intractable pneumothorax (group 2). Results: Twenty patients with AIDS (95% male, mean age 37.4 years, mean CD4 count 76 cells/ml3) underwent thoracoscopy. Surgery was performed for empyema (group 1) in 11 (55%) and intractable pneumothorax (group 2) in nine (45%). Three patients (15%) died within 30 days of the operation. At mean follow-up (29 months), overall survival was 55%. For those who survived the hospitalization and died within the follow-up period (35.3%), mean survival time was 8.2 months (range 1 month to 27 months). In group 1, surgical procedures were performed after 8 days of chest tube drainage and included pleural debridement and mechanical pleurodesis (n = 11) along with lung biopsy (n = 6). Survivals at 30 days and 29 months' follow-up were 90.9% and 45.4%, respectively. In group 2, significantly depressed CD4 counts (average 33.2 cells/ml3) were noted along with a more prolonged preoperative hospitalization (18.5 days) with 14.2 days spent with a chest tube before the operation. In this group, operative procedures included mechanical pleurodesis and talc poudrage (n = 9), bleb resection (n = 7), and lung biopsy (n = 1). Two deaths (22%) occurred within 30 days of the operation and survival at 29 months' follow-up was 66% Conclusion: Video-assisted thoracoscopic surgery performed in patients with AIDS for the treatment of empyema and intractable pneumothorax is effective, can be performed with little operative morbidity and mortality, and is associated with acceptable long-term survival. Video-assisted thoracoscopic surgery is best performed soon after the diagnosis of intractable pneumothorax or empyema has been established. (J Thorac Cardiovasc Surg 1997;114:361-6