Respiratory gases of synovial fluids: An approach to synovial tissue circulatory-metabolic imbalance in rheumatoid arthritis

doi:10.1016/S0002-9343(70)80078-X

The American Journal of Medicine

Volume 49, Issue 2, August 1970, Pages 223-231

https://doi.org/10.1016/S0002-9343(70)80078-X Get rights and content

Synovial fluids from thirty patients were analyzed for partial pressure of oxygen (P_o₂) and carbon dioxide (P_co₂), pH, lactate concentration and cell counts. Synovial biopsy specimens from twenty-four of these patients were evaluated for cellular proliferation, microvascular changes and ischemic necrosis.

P_o₂ values ranged from 53 to 9 mm Hg with corresponding ranges for pH of 7.43 to 6.84, for P_co₂ of 35 to 98 mm Hg and for lactate of 0.65 to 6.4 mM/L. Decrements in P_o₂ from 53 to 27 were associated with small decreases in pH, and minimal elevation in P_co₂ and lactate. Decrements in P_o₂ from 27 to 9 were accompanied by large decreases in pH and large increases in P_co₂ and lactate. Severe joint disease led to a fall in P_o₂ and pH and a rise in P_co₂ and lactate concentration. These changes correlated with proliferation of synovial cells, focal necrosis and focal obliterative microangiopathy.

The relationship between in vivo synovial fluid pH and P_co₂ or lactate concentration was also determined. By utilizing the Henderson-Hasselbalch equation we were able to calculate the bicarbonate concentration of each fluid and correlate the changes in bicarbonate with the increases in lactate.

A ratio of regional blood flow to joint oxygen consumption was derived from the Fick equation. By using published in vitro oxygen consumption values for synovial membrane, it was possible to calculate the relative effective blood flows in rheumatoid and nonrheumatoid joints. Regional flow is increased in rheumatoid arthritis but is relatively insufficient to meet the marked increase in metabolic demands imposed by disease. This relative insufficiency is believed to cause the fall in P_o₂ and pH in diseased synovial fluids.

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¹: From the Harvard Medical School, Department of Medicine, Peter Bent Brigham and Robert Breck Brigham Hospitals, Boston, Massachusetts 02115. This work was supported in part by NIH Grants AM-02349 and AM-05577. It was presented in part at the 1968 Interim Session of the American Rheumatism Association, Atlanta, Georgia.

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Respiratory gases of synovial fluids: An approach to synovial tissue circulatory-metabolic imbalance in rheumatoid arthritis

J Biol Chem

J Biol Chem

J Biol Chem

Vascular derangement in rheumatoid arthritis

Radioactive xenon (133Xe) disappearance rates from the synovial cavity of the human knee joint in normal and arthritic subjects

Ann Rheum Dis

Disappearance of radioactive serum albumin from joints in rheumatoid arthritis

Acta Rheum Scand

In vitro studies of rheumatoid synovium. Preliminary metabolic comparison between synovial membrane and villi

Brit J Exper Path

In vitro studies of human synovial membrane. A metabolic comparison of normal and rheumatoid tissues

Brit J Exper Path

Pathways of glucose metabolism in rheumatoid and non-rheumatoid synovial membrane

J Lab Clin Med

The physiology of synovial fluid

Arch Intern Med

The synovial membrane and the synovial fluid (with special reference to arthritis and injuries of the joint)

Radioactive xenon (¹³³Xe) disappearance rates from the synovial cavity of the human knee joint in normal and arthritic subjects