Search results for "Tissue hypoxia"
showing 6 items of 6 documents
Metabolic Status and Reaction to Heat of Normal and Tumor Tissue
1995
The occurrence of differential heating and differential thermal sensitivity between malignant tumors and normal tissues is thought to be due to limited heat dissipation and energy depletion in many solid tumors which in turn results from an inadequately functioning tumor microcirculation (Jain and Ward-Hartley 1984; Song 1984, 1991; Vaupel and Kallinowski 1987; Reinhold 1988; Vaupel et al. 1988a; Vaupel 1990). As a consequence of the latter pathophysiological condition, supply and drainage function are restricted in many solid tumors or, at least, in some tumor areas, thus creating a hostile metabolic microenvironment characterized by tissue hypoxia, acidosis, and energy depletion. Thermal …
Therapeutic Angiogenesis in Surgery and Oncology
1994
The aim of this presentation is to demonstrate the pathological importance of microenvironmental tissue hypoxia and to elucidate a general treatment concept for this situation which we have termed therapeutic angiogenesis 1. Hypoxia not only represents an insufficient oxygen supply for the cells of a given tissue area but is also regarded as an indicator for their metabolic deprivation and the concomitant accumulation of waste products. Therapeutic angiogenesis applied either with clinically established methods or using novel ways, which are the objectives of laboratory research and clinical trials at present, or in so far hypothetical forms, should lead to an expansion of the functional mi…
Relationship between hemoglobin levels and tumor oxygenation
2008
Tissue hypoxia is a powerful and independent adverse prognostic factor in solid tumors. As outlined in Chapter 11, one major factor causing tumor hypoxia is a decreased O2 transport capacity of the blood resulting from tumor-associated and/or therapy-induced anemia, which is a frequent complication seen in cancer patients (Ludwig et al. 2004; Birgegard et al. 2005).
Combined Epidural and General Anesthesia Prevents Excessive Oxygen Consumption Postoperatively
1994
In the postoperative period patients are at risk of excessive oxygen consumption (VO2). However, patients suffering from cardiovascular disease may be unable to increase their oxygen transport capacity sufficiently and may be especially vulnerable to tissue hypoxia as part of the reaction to intraoperative stress. During the last 10 years contradictory results concerning the benefits of a combined epidural and light general anesthesia have been published. Some of the results indicate that postoperative catabolism maybe depressed and that the neuroendocrine response to stress may be inhibited by such a combined technique1,2. We studied the effect of a combined epidural and light general anes…
Tumor Blood Flow and O2 Availability during Hemodilution
1984
An insufficient and heterogeneously distributed nutritive blood flow leads to an inadequate and nonuniform supply of O2 and substrates in many solid tumors (Vaupel, 1977, 1979, 1982). This deterioration of the supply conditions, which already occurs in very early growth stages and which is superimposed by a deterioration of diffusive transport during advanced growth stages, is paralleled by a decrease in the therapeutic efficacy of various cancer treatment modalities such as irradiation and chemotherapy with antiproliferative drugs. In the case of anticancer drugs, the efficiency may be reduced by affecting both pharmacokinetics and pharmacodynamics. In the latter case this is due to the de…
Effect of Localized Hyperthermia on Tumor Blood Flow and Oxygenation
1984
Hyperthermia has been shown to have a lethal effect in tumor cell cultures, particularly at temperatures above 42°C.1 Moreover, it has been demonstrated that hyperthermia retards the growth rate of certain types of malignant tumors and can be effective in completely eradicating some tumors without any major damage to normal tissue.2,3,4 The differential response of solid tumors in vivo to heat treatment in comparison to normal tissue probably results from several factors. Among these the in vivo micro-environment seems to play a decisive role. In general, the interstitial milieu of solid tumors is characterized by tissue hypoxia and anoxia5,6 and by severe tissue acidosis.7 These unfavorabl…