ABSTRACT
Carotid bodies are monitors of oxygen and glucose delivery to the brain. Faced with the threat of hypoxia or hypoglycemia carotid bodies initiate responses to counter the threat. General corrective action is to improve the perfusion by increasing the arterial blood pressure. Specific corrective actions are to stimulate ventilation to improve oxygen availability or to induce insulin resistance to raise blood glucose levels. Inappropriateness of response caused by misreading of hypoxia as hypoglycemia and hypoglycemia as hypoxia is observed experimentally and clinically. The response to all four types of hypoxia, namely, hypoxic, anemic, histotoxic and ischemic (or stagnant) hypoxia, is stimulation of ventilation and elevation of blood pressure. Ischemia produced by narrowing of the artery to the carotid body activates the carotid bodies. The activation produces hypertension, stimulation of ventilation and insulin resistance that manifests as non-insulin dependent diabetes mellitus. There is epidemiologic and necropsy evidence for the onset of atherosclerotic changes in childhood. Early atherosclerotic changes occurring in the region of carotid arteries and their bifurcation narrows the lumen of the arteries to the carotid bodies and produce hypo-perfusion of the carotid bodies. This ischemic hypoxia is a causative, or at least a permissive factor for hypertension and/or non-insulin dependent diabetes mellitus. It is suggested that neither non-insulin dependent diabetes mellitus causes hypertension nor hypertension causes diabetes mellitus, but both are caused by dysfunctional carotid bodies.
Subject(s)
Arteriosclerosis/epidemiology , Arteriosclerosis/physiopathology , Carotid Body/physiopathology , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/physiopathology , Hypertension/epidemiology , Hypertension/physiopathology , Animals , Causality , Diabetes Mellitus, Type 2/etiology , Evidence-Based Medicine , Humans , Hypertension/etiology , Models, Cardiovascular , Risk Assessment/methods , Risk FactorsABSTRACT
BACKGROUND: Interplay between wound resistance factors and bacterial innoculum determines the risk of surgical infection. Since cautery causes more damage than the scalpel, our hypothesis is that lower numbers of bacteria are required to infect wounds made by electric cautery than to infect wounds made with a scalpel. METHODS: Abdominal fascia was incised in 375 rats by cold knife, cutting current, or coagulation current. Wounds were innoculated with increasing numbers of bacteria and histologically scored at 7 days for necrosis, inflammation, and abscess. RESULTS: Coagulation current causes more inflammation, necrosis, and abscesses than the scalpel at all bacterial levels. Electric cutting current is intermediate, causing more damage than the scalpel only after contamination reached 10(5). Above this threshold most wounds were infected in all groups. CONCLUSIONS: Electric coagulation current should be used only when the need for meticulous hemostasis outweighs the considerably increased risk of infection. Electric cutting current is less destructive but also less hemostatic; indications for its use are difficult to identify.
Subject(s)
Bacterial Infections/etiology , Electrocoagulation/adverse effects , Surgical Wound Infection/etiology , Animals , General Surgery/history , History, 16th Century , History, 19th Century , History, 20th Century , History, Ancient , Inflammation/etiology , Necrosis , Rats , Rats, Sprague-DawleyABSTRACT
A patient presented with an unusual case of a breast mass. History and meticulous physical examination led to the diagnosis of metastatic melanoma, which was confirmed by biopsy. The differential diagnosis of metastasis to breast is discussed.
