Abstract
Erythropoietin (rHuEPO) has proven to be effective in the treatment of anemia of chronic renal failure (CRF). Despite improving the quality of life, peak oxygen uptake after rHuEPO therapy is not improved as much as the increase in hemoglobin concentration ([Hb)] would predict. We hypothesized that this discrepancy is due to failure of O2 transport rates to rise in a manner proportional to [Hb]. To test this, eight patients with CRF undergoing regular hemodialysis were studied pre- and post-rHuEPO ([Hb] = 7.5 +/- 1.0 vs. 12.5 +/- 1.0 g x dl-1) using a standard incremental cycle exercise protocol. A group of 12 healthy sedentary subjects of similar age and anthropometric characteristics served as controls. Arterial and femoral venous blood gas data were obtained and coupled with simultaneous measurements of femoral venous blood flow (Qleg) by thermodilution to obtain O2 delivery and oxygen uptake (VO2). Despite a 68% increase in [Hb], peak VO2 increased by only 33%. This could be explained largely by reduced peak leg blood flow, limiting the gain in O2 delivery to 37%. At peak VO2, after rHuEPO, O2 supply limitation of maximal VO2 was found to occur, permitting the calculation of a value for muscle O2 conductance from capillary to mitochondria (DO2). While DO2 was slightly improved after rHuEPO, it was only 67% of that of sedentary control subjects. This kept maximal oxygen extraction at only 70%. Two important conclusions can be reached from this study. First, the increase in [Hb] produced by rHuEPO is accompanied by a significant reduction in peak blood flow to exercising muscle, which limits the gain in oxygen transport. Second, even after restoration of [Hb], O2 conductance from the muscle capillary to the mitochondria remains considerably below normal.
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- Agustí A. G., Roca J., Barberá J. A., Casademont J., Rodriguez-Roisin R., Wagner P. D. Effect of sampling site on femoral venous blood gas values. J Appl Physiol (1985) 1994 Oct;77(4):2018–2022. doi: 10.1152/jappl.1994.77.4.2018. [DOI] [PubMed] [Google Scholar]
- Bebout D. E., Hogan M. C., Hempleman S. C., Wagner P. D. Effects of training and immobilization on VO2 and DO2 in dog gastrocnemius muscle in situ. J Appl Physiol (1985) 1993 Apr;74(4):1697–1703. doi: 10.1152/jappl.1993.74.4.1697. [DOI] [PubMed] [Google Scholar]
- Bradley J. R., Anderson J. R., Evans D. B., Cowley A. J. Impaired nutritive skeletal muscle blood flow in patients with chronic renal failure. Clin Sci (Lond) 1990 Sep;79(3):239–245. doi: 10.1042/cs0790239. [DOI] [PubMed] [Google Scholar]
- Davenport A. The effect of treatment with recombinant human erythropoietin on skeletal muscle function in patients with end-stage renal failure treated with regular hospital hemodialysis. Am J Kidney Dis. 1993 Nov;22(5):685–690. doi: 10.1016/s0272-6386(12)80431-8. [DOI] [PubMed] [Google Scholar]
- Diesel W., Emms M., Knight B. K., Noakes T. D., Swanepoel C. R., van Zyl Smit R., Kaschula R. O., Sinclair-Smith C. C. Morphologic features of the myopathy associated with chronic renal failure. Am J Kidney Dis. 1993 Nov;22(5):677–684. doi: 10.1016/s0272-6386(12)80430-6. [DOI] [PubMed] [Google Scholar]
- Eschbach J. W., Adamson J. W. Recombinant human erythropoietin: implications for nephrology. Am J Kidney Dis. 1988 Mar;11(3):203–209. doi: 10.1016/s0272-6386(88)80150-1. [DOI] [PubMed] [Google Scholar]
- Eschbach J. W., Egrie J. C., Downing M. R., Browne J. K., Adamson J. W. Correction of the anemia of end-stage renal disease with recombinant human erythropoietin. Results of a combined phase I and II clinical trial. N Engl J Med. 1987 Jan 8;316(2):73–78. doi: 10.1056/NEJM198701083160203. [DOI] [PubMed] [Google Scholar]
- Eschbach J. W., Mladenovic J., Garcia J. F., Wahl P. W., Adamson J. W. The anemia of chronic renal failure in sheep. Response to erythropoietin-rich plasma in vivo. J Clin Invest. 1984 Aug;74(2):434–441. doi: 10.1172/JCI111439. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fan F. C., Chen R. Y., Schuessler G. B., Chien S. Effects of hematocrit variations on regional hemodynamics and oxygen transport in the dog. Am J Physiol. 1980 Apr;238(4):H545–H522. doi: 10.1152/ajpheart.1980.238.4.H545. [DOI] [PubMed] [Google Scholar]
- Hogan M. C., Bebout D. E., Wagner P. D. Effect of hemoglobin concentration on maximal O2 uptake in canine gastrocnemius muscle in situ. J Appl Physiol (1985) 1991 Mar;70(3):1105–1112. doi: 10.1152/jappl.1991.70.3.1105. [DOI] [PubMed] [Google Scholar]
- Keller M. W., Damon D. N., Duling B. R. Determination of capillary tube hematocrit during arteriolar microperfusion. Am J Physiol. 1994 Jun;266(6 Pt 2):H2229–H2238. doi: 10.1152/ajpheart.1994.266.6.H2229. [DOI] [PubMed] [Google Scholar]
- Lundin A. P., Akerman M. J., Chesler R. M., Delano B. G., Goldberg N., Stein R. A., Friedman E. A. Exercise in hemodialysis patients after treatment with recombinant human erythropoietin. Nephron. 1991;58(3):315–319. doi: 10.1159/000186443. [DOI] [PubMed] [Google Scholar]
- Macdougall I. C., Lewis N. P., Saunders M. J., Cochlin D. L., Davies M. E., Hutton R. D., Fox K. A., Coles G. A., Williams J. D. Long-term cardiorespiratory effects of amelioration of renal anaemia by erythropoietin. Lancet. 1990 Mar 3;335(8688):489–493. doi: 10.1016/0140-6736(90)90733-l. [DOI] [PubMed] [Google Scholar]
- Mayer G., Thum J., Graf H. Anaemia and reduced exercise capacity in patients on chronic haemodialysis. Clin Sci (Lond) 1989 Mar;76(3):265–268. doi: 10.1042/cs0760265. [DOI] [PubMed] [Google Scholar]
- McMahon L. P., Johns J. A., McKenzie A., Austin M., Fowler R., Dawborn J. K. Haemodynamic changes and physical performance at comparative levels of haemoglobin after long-term treatment with recombinant erythropoietin. Nephrol Dial Transplant. 1992;7(12):1199–1206. doi: 10.1093/ndt/7.12.1199. [DOI] [PubMed] [Google Scholar]
- Metra M., Cannella G., La Canna G., Guaini T., Sandrini M., Gaggiotti M., Movilli E., Dei Cas L. Improvement in exercise capacity after correction of anemia in patients with end-stage renal failure. Am J Cardiol. 1991 Oct 15;68(10):1060–1066. doi: 10.1016/0002-9149(91)90496-8. [DOI] [PubMed] [Google Scholar]
- Moore G. E., Bertocci L. A., Painter P. L. 31P-magnetic resonance spectroscopy assessment of subnormal oxidative metabolism in skeletal muscle of renal failure patients. J Clin Invest. 1993 Feb;91(2):420–424. doi: 10.1172/JCI116217. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Moore G. E., Parsons D. B., Stray-Gundersen J., Painter P. L., Brinker K. R., Mitchell J. H. Uremic myopathy limits aerobic capacity in hemodialysis patients. Am J Kidney Dis. 1993 Aug;22(2):277–287. doi: 10.1016/s0272-6386(12)70319-0. [DOI] [PubMed] [Google Scholar]
- Painter P., Moore G. E. The impact of recombinant human erythropoietin on exercise capacity in hemodialysis patients. Adv Ren Replace Ther. 1994 Apr;1(1):55–65. doi: 10.1016/s1073-4449(12)80022-7. [DOI] [PubMed] [Google Scholar]
- Piiper J., Scheid P. Model for capillary-alveolar equilibration with special reference to O2 uptake in hypoxia. Respir Physiol. 1981 Dec;46(3):193–208. doi: 10.1016/0034-5687(81)90121-3. [DOI] [PubMed] [Google Scholar]
- Robertson H. T., Haley N. R., Guthrie M., Cardenas D., Eschbach J. W., Adamson J. W. Recombinant erythropoietin improves exercise capacity in anemic hemodialysis patients. Am J Kidney Dis. 1990 Apr;15(4):325–332. doi: 10.1016/s0272-6386(12)80079-5. [DOI] [PubMed] [Google Scholar]
- Roca J., Agusti A. G., Alonso A., Poole D. C., Viegas C., Barbera J. A., Rodriguez-Roisin R., Ferrer A., Wagner P. D. Effects of training on muscle O2 transport at VO2max. J Appl Physiol (1985) 1992 Sep;73(3):1067–1076. doi: 10.1152/jappl.1992.73.3.1067. [DOI] [PubMed] [Google Scholar]
- Roca J., Hogan M. C., Story D., Bebout D. E., Haab P., Gonzalez R., Ueno O., Wagner P. D. Evidence for tissue diffusion limitation of VO2max in normal humans. J Appl Physiol (1985) 1989 Jul;67(1):291–299. doi: 10.1152/jappl.1989.67.1.291. [DOI] [PubMed] [Google Scholar]
- Roca J., Sanchis J., Agusti-Vidal A., Segarra F., Navajas D., Rodriguez-Roisin R., Casan P., Sans S. Spirometric reference values from a Mediterranean population. Bull Eur Physiopathol Respir. 1986 May-Jun;22(3):217–224. [PubMed] [Google Scholar]
- Rosberg B., Wulff K. Regional blood flow in normovolaemic and hypovolaemic haemodilution. An experimental study. Br J Anaesth. 1979 May;51(5):423–430. doi: 10.1093/bja/51.5.423. [DOI] [PubMed] [Google Scholar]
- Satoh K., Masuda T., Ikeda Y., Kurokawa S., Kamata K., Kikawada R., Takamoto T., Marumo F. Hemodynamic changes by recombinant erythropoietin therapy in hemodialyzed patients. Hypertension. 1990 Mar;15(3):262–266. doi: 10.1161/01.hyp.15.3.262. [DOI] [PubMed] [Google Scholar]
- Wagner P. D. Algebraic analysis of the determinants of VO2,max. Respir Physiol. 1993 Aug;93(2):221–237. doi: 10.1016/0034-5687(93)90007-w. [DOI] [PubMed] [Google Scholar]
- Wagner P. D. Diffusion and chemical reaction in pulmonary gas exchange. Physiol Rev. 1977 Apr;57(2):257–312. doi: 10.1152/physrev.1977.57.2.257. [DOI] [PubMed] [Google Scholar]
- Wagner P. D., Roca J., Hogan M. C., Poole D. C., Bebout D. C., Haab P. Experimental support for the theory of diffusion limitation of maximum oxygen uptake. Adv Exp Med Biol. 1990;277:825–833. doi: 10.1007/978-1-4684-8181-5_94. [DOI] [PubMed] [Google Scholar]
- Winearls C. G., Oliver D. O., Pippard M. J., Reid C., Downing M. R., Cotes P. M. Effect of human erythropoietin derived from recombinant DNA on the anaemia of patients maintained by chronic haemodialysis. Lancet. 1986 Nov 22;2(8517):1175–1178. doi: 10.1016/s0140-6736(86)92192-6. [DOI] [PubMed] [Google Scholar]
- Wittenberg B. A., Wittenberg J. B. Effects of carbon monoxide on isolated heart muscle cells. Res Rep Health Eff Inst. 1993 Dec;(62):1–21. [PubMed] [Google Scholar]