Halperin M L, Kamel K S, Cheema-Dhadli S
Renal Division, St. Michael's Hospital, University of Toronto, Canada.
Mt Sinai J Med. 1992 Jan;59(1):1-12.
Three cases are presented to illustrate that quantitative analysis based on physiologic principles can help resolve certain controversies in clinical medicine. For example, in case 1, a patient with severe hypoxia, the rate of production of lactic acid is so high that only restoration of delivery of oxygen is rational therapy. If the degree of hypoxia exceeds 5.6% of demand, dichloroacetate will not lessen the degree of acidosis. Further, even when delivery of oxygen is returned to normal, the rate of fall in lactate and rise in bicarbonate in plasma will be relatively slow. In case 2, a patient with diabetic ketoacidosis, our discussion stresses that the rate of production of ketoacids is not that rapid and that the degree of ketoacidosis is influenced to a major degree by decreasing the rate of oxidation of ketoacids in brain and kidneys. Case 3, a patient with severe hyperglycemia, illustrates that insulin will only promote the oxidation of glucose at a rapid rate once the levels of fatty acids and ketoacids decline to low levels. Accelerated transport of glucose by insulin is only a permissive action for the oxidation of glucose.
现列举三个病例以说明基于生理学原理的定量分析有助于解决临床医学中的某些争议。例如，在病例1中，一名患有严重缺氧的患者，乳酸生成速率极高，以至于只有恢复氧气输送才是合理的治疗方法。如果缺氧程度超过需求的5.6%，二氯乙酸并不会减轻酸中毒程度。此外，即使氧气输送恢复正常，血浆中乳酸下降速率和碳酸氢根上升速率也会相对较慢。在病例2中，一名患有糖尿病酮症酸中毒的患者，我们的讨论强调酮酸生成速率并非那么快，且酮症酸中毒程度在很大程度上受脑和肾中酮酸氧化速率降低的影响。病例3，一名患有严重高血糖的患者，表明只有当脂肪酸和酮酸水平降至低水平时，胰岛素才会以快速速率促进葡萄糖氧化。胰岛素加速葡萄糖转运只是葡萄糖氧化的一种允许作用。
