Differences of cardiac output measurements by open-circuit acetylene uptake in pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension: a cohort study

Respiratory Research

Thomas M Berghaus¹  Wolfgang von Scheidt¹  Christian Faul¹  Martin Schwaiblmair¹ 

[1] 1. Department of Internal Medicine, Klinikum Augsburg, Ludwig-Maximilians-University Munich, Stenglinstrasse 2, D-86156 Augsburg, Germany

关键词: Thermodilution;    Single-breath open-circuit acetylene uptake;    Cardiac output;    Chronic thromboembolic pulmonary hypertension;    Pulmonary arterial hypertension;   

Others  :  796744
DOI  :  10.1186/1465-9921-13-18

 received in 2011-12-07, accepted in 2012-03-12,  发布年份 2012

【 摘 要 】

Background

As differences in gas exchange between pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) have been demonstrated, we asked if cardiac output measurements determined by acetylene (C₂H₂) uptake significantly differed in these diseases when compared to the thermodilution technique.

Method

Single-breath open-circuit C₂H₂ uptake, thermodilution, and cardiopulmonary exercise testing were performed in 72 PAH and 32 CTEPH patients.

Results

In PAH patients the results for cardiac output obtained by the two methods showed an acceptable agreement with a mean difference of -0.16 L/min (95% CI -2.64 to 2.32 L/min). In contrast, the agreement was poorer in the CTEPH group with the difference being -0.56 L/min (95% CI -4.96 to 3.84 L/min). Functional dead space ventilation (44.5 ± 1.6 vs. 32.2 ± 1.4%, p < 0.001) and the mean arterial to end-tidal CO₂ gradient (9.9 ± 0.8 vs. 4.1 ± 0.5 mmHg, p < 0.001) were significantly elevated among CTEPH patients.

Conclusion

Cardiac output evaluation by the C₂H₂ technique should be interpreted with caution in CTEPH, as ventilation to perfusion mismatching might be more relevant than in PAH.

【 授权许可】

   
2012 Schwaiblmair et al; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

【 参考文献 】

• [1]ESC/ERS Guidelines: Guidelines for the diagnosis and treatment of pulmonary hypertension. Eur Heart J 2009, 30:2493-2537.
• [2]Hoeper M, Maier R, Tongers J, Niedermeyer J, Hohlfeld J, Hamm M, Fabel H: Determination of cardiac output by the Fick method, thermodiluation, and acetylene rebreathing in pulmonary hypertension. Am J Respir Crit Care Med 1999, 160:535-541.
• [3]Hsia C, Herazo L, Ramanathan M, Johnson R: Cardiac output during exercise measured by acetylene rebreathing thermodiluation, and Fick techniques. J Appl Physiol 1995, 78:1612-1616.
• [4]Jarvis S, Levine B, Prisk G, Shykoff B, Elliott A, Rosow E, Blomqvist C, Pawelczyk J: Simultaneous determination of the accuracy and precision of closed-circuit cardiac output rebreathing techniques. J Appl Physiol 2007, 103:867-874.
• [5]Barker R, Hopkins S, Kellogg N, Olfert I, Brutsaert T, Gavin T, Entin P, Rice A, Wagner P: Measurement of cardiac output during exercise by open-circuit acetylene uptake. J Appl Physiol 1999, 87:1506-1512.
• [6]Johnson B, Beck K, Proctor D, Miller J, Dietz N, Joyner M: Cardiac output during exercise by the open circuit acetylene washin method: comparison with direct Fick. J Appl Physiol 2000, 88:1650-1658.
• [7]Zhai Z, Murphy K, Tighe H, Wang C, Wilkins MR, Gibbs JS, Howard LS: Differences in ventilatory inefficiency between pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension. Chest 2011, 140(5):1284-1291.
• [8]Wasserman K, Hansen J, Sue D, Stringer W, Whipp B: Principles of Exercise Testing and Interpretation. 4th edition. Baltimore: Lippincott Williams & Wilkens; 2004.
• [9]Bland JM, Altman DG: Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1986, 1(8476):307-310.
• [10]Sherman M, Kosinski R, Paz H, Campbell D: Measuring cardiac output in critically ill patients: disagreement between thermodilution-, calculated, expired gas-, and oxygen consumption-based methods. Cardiology 1997, 88:19-25.
• [11]van Grondelle A, Ditchey RV, Groves BM, Wagner WW Jr, Reeves JT: Thermodilution method overestimates low cardiac output in humans. Am J Physiol 1983, 245(4):690-692.
• [12]Dantzker DR, Bower JS: Mechanisms of gas exchange abnormality in patients with chronic obliterative pulmonary vascular disease. J Clin Invest 1979, 64(4):1050-1055.
• [13]Dantzker DR, D'Alonzo GE, Bower JS, Popat K, Crevey BJ: Pulmonary gas exchange during exercise in patients with chronic obliterative pulmonary hypertension. Am Rev Respir Dis 1984, 130(3):412-416.
• [14]D'Alonzo GE, Bower JS, Dantzker DR: Differentiation of patients with primary and thromboembolic pulmonary hypertension. Chest 1984, 85(4):457-461.
• [15]Kapitan KS, Buchbinder M, Wagner PD, Moser KM: Mechanisms of hypoxemia in chronic thromboembolic pulmonary hypertension. Am Rev Respir Dis 1989, 139(5):1149-1154.
• [16]Kapitan KS, Clausen JL, Moser KM: Gas exchange in chronic thromboembolism after pulmonary thromboendarterectomy. Chest 1990, 98(1):14-19.
• [17]Waurick PE, Kleber XF: Arterial and End-Tidal CO2 Partial Pressures in patients with Acute and Chronic Pulmonary Embolism and Primary Pulmonary Hypertension. In Cardiopulmonary Exercise Testing in Pulmonary Vascular Disease. Cardiopulmonary Exercise Testing and Cardiovascular Health. Edited by Wasserman K. New York: Futura Publishing Company; 2002:173-178.
• [18]Scheidl SJ, Englisch C, Kovacs G, Reichenberger F, Schulz R, Breithecker A, Ghofrani HA, Seeger W, Olschewski H: Diagnosis of CTEPH vs. IPAH using capillary to end-tidal CO2 gradients. Eur Respir J 2012, 39(1):119-124.
• [19]Delcroix M, Mélot C, Vachiéry JL, Lejeune P, Leeman M, Vanderhoeft P, Naeije R: Effects of embolus size on hemodynamics and gas exchange in canine embolic pulmonary hypertension. J Appl Physiol 1990, 69(6):2254-2261.
• [20]Tuder RM, Abman SH, Braun T, Capron F, Stevens T, Thistlethwaite PA, Haworth SG: Development and pathology of pulmonary hypertension. J Am Coll Cardiol 2009, 54(Suppl 1):3-9.
• [21]Heerdt PM, Pond CG, Blessios GA, Rosenbloom M: Inaccuracy of cardiac output by thermodilution during acute tricuspid regurgitation. Ann Thorac Surg 1992, 53(4):706-708.