CLINICAL EXPERIENCE WITH CONTINUOUS MUSCLE pH MONITORING AS AN INDEX OF TISSUE PERFUSIONAND OXYGENATION AND ACID-BASE STATUS

Tissue surface pH monitoring during reduced blood flow: Metabolic implications and sources of error

“…4). Thus, tissue surface pH may bear a specific relationship to peripheral oxygen requirements under the conditions of this study (but not to blood pH) äs previously suggested in similar work [6,10]. On the other hand, tissue surface pH has also been shown to vary directly with arterial blood pH when peripheral perfusiori is presumed normal [18].…”

“…This cannot be said for pH terminology in regard to other organs since it has received various labels from several authors. For example, FILLER, et al [5,6] have implanted electrodes subfascially and originally coined the phrase "muscle surface pH" for their measurement. More recently, this pH measurement has been referred to äs tissue pH [11] or similarly tissue surface pH.…”

“…Low tissue surface pH in the absence of low blood pH has been observed in both adults and children suffering from occult blood loss [4,5,6,9,14,15] or peripheral vascular disease [11,12,13]. For this reason, it has been suggested that continuous measurement of tissue surface pH may be useful for monitoring metabolic acidosis resulting from reduced blood flow [13].…”

Effects of Acute Bleeding on Oxygen Supply to the Skeletal Muscle in Dogs

“…The technique of p,Û2 measurements by means of a muiliwire polarographic elec trode which allows p,02 histogram construc tion has been introduced to describe tissue oxygenation in a variety of pathophysiologi cal situations [11, 15-18, 21, 23], This tech nique permits the direct measurement of p,C>2 and should give more accurate reflec tion of tissue oxygenation than muscle pH, which is an indirect measurement depending upon lactic acid production as a result of anaerobic metabolism [4,6]. Although mea surements are limited to the surface, and therefore probably open to criticism, the noninvasive nature of the technique with re spect to the tissue in question avoids tissue damage and the resulting hyperemia and hemorrhage which are easily associated with invasive kinds of p,02 measurements using needle electrodes, Silastic tube tonometers, or mass spectrometer techniques [3,7,10,19,24], Our data show that under normal condi tions the pt02 histogram, composed of 104 p,02 values obtained from a surface area 0.5 cm in diameter, shows a characteristic distri bution pattern.…”