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Approximately 60% of locally advanced carcinomas of the uterine cervix exhibit hypoxic and/or anoxic tissue areas which are heterogeneously distributed within the tumor mass. Hypoxia is caused by structural and functional abnormalities of the newly formed tumor vessels arising from neovascularization, by a disturbed microcirculation, enlarged diffusion distances and by tumor- or therapy-associated anemia. The extent of pretherapeutically measured hypoxic tissue areas is independent of clinical size, FIGO stage and histopathological grade of squamous cell carcinomas of the uterine cervix. Anemia can intensify tumor hypoxia. O2-tensions in local recurrences are even lower than those in the primary tumors. About 78% of recurrent tumors exhibit hypoxic tissue areas. Hypoxia is known to directly or indirectly (e.g., via cell cycle effects) affect the therapeutic efficacy of sparsely ionizing radiation and some forms of chemotherapy. Sustained tissue hypoxia may also cause molecular changes that can result in a more malignant phenotype, a process termed malignant progression. Based on this association between tumor hypoxia and malignant progression, tumor oxygenation has proven to be an independent, powerful prognostic factor of local control, overall and disease-free survival. In addition, the routine evaluation of the pretherapeutic oxygenation status may enable individual therapeutic strategies, independent of other oncologic parameters.

Water-filtered infrared-A-radiation (IR/A-HT) can be used to heat superficial malignant tumors. A prospective multicenter phase I-II study was conducted to evaluate toxicity and efficacy of IR/A-HT combined with external beam radiotherapy (RT).From December 1991 to June 1994, a total of 53 patients with 58 malignant lesions were entered in the study. There were 14 primary, 36 recurrent and 8 metastatic tumors which were located in the head and neck region (14), chest wall (31), abdominal wall (2) and the extremities (11). The mean tumor volume was 100 cm3. IR/A-HT was applied 1 to 2 times per week with up to 3 IR/A-HT-radiators directly before or after external RT for 1 hour at 40.5 to 44 degrees C. Temperatures were controlled at various locations at the skin surface and invasively at depth.IR/A-HT was well tolerated: in 31 (53%) lesions acute (pain, pulse or blood pressure changes, increased skin reaction etc.) and in 25 (43%) chronic side-effects (atrophy, telangiectasis, fibrosis etc.) were noted; usually the toxicity was minor and temporary. At 3 months FU, 32 (55%) lesions achieved a local CR and 19 (35%) a PR; at 12 months FU, 25 (43%) had persistent CR; 16 patients (18 lesions) were deceased and 3 (4 lesions) not yet in FU. In univariate analysis the following prognostic factors for CR at 3 or 12 months FU were found: Karnofsky, metastatic status, tumor size, total RT-dose, thermal parameters T min(av) and T mean. For acute toxicity maximum temperature Tmax(av) was prognostically decisive. Significant differences were also found when considering the "quality of the HT-application". The microwave technique was superior to the infrared-A-HT-technique with regard to the penetration depth of energy deposition.Water-filtered infrared-A-radiation can be safely and effectively applied to heat localized superficial tumors (up to 1 cm depth). To increase the area of HT application multiple infrared-A-radiators have to be combined. A multi-element-system is in progress.

In Sprague-Dawley rats anaesthetized with pentobarbital-Na and breathing spontaneously, regional hepatic blood flow (rHBF) is measured in the liver in situ and during application of peloid paraffin packs on the abdominal wall. Blood flow measurements are performed by means of the 85Kr(beta)-clearance technique after slug injection of the dissolved indicator into the thoracic aorta. Mean arterial blood pressure is monitored continuously. After exposing the liver surface by an incision at the right costal margin, rHBF is measured, 5, 15, 35 and 45 min later. The results of a control series clearly show that there exists a time-dependent decrease of rHBF at comparable M ABP values and normal respiratory gas parameters. If peloid paraffin packs are applied on the abdominal wall 25 min after the surgery, this time-dependent decrease of rHBF ceases and rHBF then increases to initial values. In comparison to the control series the application of peloid paraffin packs on the abdominal wall causes a significant increase in rHBF of about 20--39%. Experiments on bile flow of rats show that under normal conditions and after insertion of a cannula into the common hepatic duct, a time-independent mean flow of 0.053 ml bile/kg body weight/min occurs. The application of peloid paraffin packs 45 min after the suture of the abdominal wall yields a significant increase in bile flow of 18% within 15 min.

In order to determine the interdependence of the parameters of the respiratory gas transport in rat blood (Sprague-Dawley) CO-2-equilibration curves in fully oxygenated and deoxygenated blood are measured. The results are presented in the form of pH-log P-CO-2-diagrams. O-2-dissociation curves of rat blood are registered at different CO-2 partial pressures. The P-02 at S-02 equals 50% ranged between 27.7 mm Hg for P-C0-2 equals 20 mm Hg. 35.1 mm Hg for P-C0-2 equals 40 mm Hg and 42.2 for P-C0-2 equals 60 mm Hg. Cartesian and alignment nomograms are constructed using CO-2 equilibration curves and O-2 dissociation curves. These nomograms give the interrelations between P-O-2, P-CO-2, pH and S-0-2 of rat blood. Separate nomograms are presented for Hb-concentrations of 10-13 g-% and 13.1-16 g-% because of great variations of Hb concentration in rat blood. If two of these values are known the nomograms permit the reading of the remaining paramters.

Results obtained with the classical Westergen method for measuring erythrocyte sedimentation rate was compared with a method in which the tubes were angled at 60 degree. Blood was obtained from 31 healthy controls and 30 hospitalised patients. Blood from the controls gave similar results with both methods. On the other hand, in patients with a raised ESR by Westergren, the two methods agreed in only 10% of cases. In most instances the angled-tube method gave values below those by Westergren, although elevated under clinical aspects. In some Instances the angled-tube method gave such low readings in clearly pathological samples that the ESR was falsely interpreted as normal. It is concluded that the angled-tube method is not valid for ESR measurement after Westergren, because it measures something different than the classical Westergren method.

Blood samples were taken from the splenic artery, vein and pulp of 16 patients suffering from lymphoproliferative diseases, essential thrombocytopenia or hereditary spherocytosis and undergoing early splenectomy. The relevant parameters of the respiratory gas exchange as well as glucose and lactate concentrations were determined in these samples. In no case did the thorough examination of the splenic tissue reveal any histopathologic aspects. Taking into account a mean splenic blood flow of 100 ml/100 g/min during anaesthesia, the mean oxygen consumption of the splenic tissue attains 1.1 ml/100 g/min. The glucose uptake and the lactate release show to be 9 mg/100 g/min and 5.2 mg/100 g/min, respectively. Despite high glucose uptake rates and pronounced glycolytic activities there is no evidence of the existence of low pH values, a glucose depletion or hypoxia in the normal spleen. In the normal spleen, therefore, the intrasplenic sequestration of red blood cells cannot be explained by unfavourable metabolic conditions.