Trigger points in painful muscle are a characteristic sign in patients with primary fibromyalgia. The MDO oxygen electrode was used to evaluate oxygenation in the subcutaneous tissue and in trigger points in the trapezius and brachioradial muscles. Ten patients and 8 normal controls were studied. The results in the patients were abnormal, with scattered or slalom-slope histograms, indicating low tissue oxygenation. The controls were normal, except in one case. The conclusion is that in patients with primary fibromyalgia, the muscle oxygenation is abnormal or low, at least in the trigger point area of the muscles.

Muscle Tissue Oxygen Pressure in Primary Fibromyalgia

The major problem in volume replacement therapy using erythrocyte free solutions is the maintenance of adequate oxygen supply to the tissues. Inspite of the wide spread use of dextran solutions the effects on oxygen transport and oxygen supply to the tissues are still not fully understood. The aim of this paper is therefore to present conclusive evidence about the effects of dextran on tissue oxygenation, discussing not only its effects on the macrohemodynamics and microcirculatory flow but discussing as well its influence on the respiratory function of the blood.

Oxygen Transport and Tissue Oxygenation During Hemodilution with Dextran

The effect of a stepwise decrease in PaCO2 from 3.9-1.6 kPa on rCBF, rCMRO2, tissue PO2 and concentrations of glucose, lactate, pyruvate, ATP, ADP, AMP and phosphocreatine in the brain cortex was studied in cats lightly anaesthetized with sodium pentobarbital. 1. Moderate lowering of PaCO2 to 2.5 kPa induced in all animals a homogeneous decrease of rCBF in corresponding areas of the right and left hemisphere. Mean rCBF fell from 129.2 to 103.1 ml X 100 g-1 X min-1, while rCMRO2 remained unchanged (12.7-12.9 ml X 100 g-1 X min-1). The tissue PO2 frequency histograms showed a shift to lower values without indicating the presence of brain tissue hypoxia. 2. Severe arterial hypocapnia (PaCO2 = 1.6 kPa) caused an inhomogeneous blood flow reaction. Both further decreased as well as increased rCBF values were measured simultaneously in the brain cortex of individual animals (mean rCBF = 97.6 ml X 100 g-1 X min-1). At the same time tissue PO2 measurements and metabolite assays indicated the presence of pronounced brain tissue hypoxia. The tissue concentrations of lactate and pyruvate and the lactate/pyruvate ratio were significantly increased, while the phosphocreatine concentration was significantly reduced. In addition, rCMRO2 decreased to 11.3 ml X 100 g-1 X min-1. The results provide conclusive evidence that severe arterial hypocapnia leads to an insufficient O2 supply of the brain cortex, which in turn seems to counteract the influence of hypocapnia on cortical blood flow regulation.

Effects of severe arterial hypocapnia on regional blood flow regulation, tissue PO2 and metabolism in the brain cortex of cats.

Effects of diaspirin-cross-linked hemoglobin (dclhbtm) on local tissue oxygen tension in striated skin muscle: An efficacy study in the hamster

The MDO (Mehrdraht Dortmund Oberflache) oxygen electrode was used for studies of tissue oxygen pressure fields (presented as histograms) in healthy human volunteers breathing room air and gas mixtures with different oxygen concentrations. Forearm blood flow measurements were performed with strain gauge plethysmography, and local blood flow and permeability-surface area product (PS) were studied by the clearances of 133xenon and 51Cr-EDTA. At ordinary arterial oxygen pressure levels the histograms were normal, i.e. their distribution type was approximately Gaussian. Higher arterial oxygen pressures caused changes in tissue oxygenation. However, at arterial oxygen pressure levels above 31 kPa two types of abnormal histogram distribution types were distinguished: scattered multi-population histograms (type a) and a type with predominantly low values (type b). Mean forearm blood flow showed only minor variations, whereas the clearances of 133xenonand and 51Cr-EDTA were higher with higher PaO2. A parallel increase was also seen in PS.

W. Grunewald

Papers

Possibilities of Measuring Oxygen Pressure Fields in Tissue by Multiwire Platinum Electrodes