Brazilian Journal of Anesthesiology
https://app.periodikos.com.br/journal/rba/article/doi/10.1590/S0034-70942004000500002
Brazilian Journal of Anesthesiology
Scientific Article

Avaliação da correlação entre o dióxido de carbono expirado e o débito cardíaco em pacientes submetidos à cirurgia cardíaca com circulação extracorpórea

Correlation between end-tidal carbon dioxide levels and cardiac output during cardiac surgery with cardiopulmonary bypass

Karina Takesaki Miyaji; Roberto Iara Buscati; Antônio José Arraiz Rodriguez; Luciano Brandão Machado; Luiz Marcelo Sá Malbouisson; Maria José Carvalho Carmona

http://dx.doi.org/10.1590/S0034-70942004000500002 Braz J Anesthesiol, vol.54, n5, p.625-633, 2004
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Resumo

JUSTIFICATIVA E OBJETIVOS: O CO2 expirado (P ET CO2) reflete, além da ventilação pulmonar (eliminação), a produção de dióxido de carbono (metabolismo) e o fluxo sangüíneo pulmonar (circulação). Quando o metabolismo e a ventilação são constantes, o CO2 expirado reflete o fluxo sangüíneo pulmonar e, desta forma, o débito cardíaco (DC). Este estudo tem como objetivo a avaliação da correlação entre o dióxido de carbono expirado (P ET CO2) e o débito cardíaco em pacientes submetidos à cirurgia cardíaca com circulação extracorpórea (CEC). MÉTODO: Foram estudados 25 pacientes submetidos à cirurgia de revascularização miocárdica com CEC. Após a intubação traqueal iniciou-se a monitorização da P ET CO2. A determinação do débito cardíaco (DC) foi feita por método de termodiluição com o uso de cateter de Swan-Ganz e a PaCO2 foi avaliada através de gasometria arterial. Os parâmetros do estudo foram avaliados em quatro momentos: logo após a indução da anestesia geral; antes da circulação extracorpórea, ao término da circulação extracorpórea e ao final da cirurgia. RESULTADOS: O teste estatístico não demonstrou uma correlação entre o CO2 expirado e o DC, assim como o gradiente de dióxido de carbono arterial e expirado (Ga-eCO2) e o DC. Foi encontrada correlação entre a variação dos valores da P ET CO2, Ga-eCO2 e DC em relação ao basal antes da CEC com perda da correlação após a CEC até o final da cirurgia. CONCLUSÕES: Neste estudo, onde se avaliam pacientes submetidos à cirurgia cardíaca com CEC, as alterações de relação ventilação/perfusão ocorridas ao longo do procedimento são, provavelmente, os fatores determinantes da diminuição da correlação entre o débito cardíaco e o valor de dióxido de carbono expirado.

Palavras-chave

CIRURGIA, MONITORIZAÇÃO, MONITORIZAÇÃO

Abstract

BACKGROUND AND OBJECTIVES: End-tidal carbon dioxide (P ET CO2) not only reflects pulmonary ventilation but also carbon dioxide production (metabolism) and pulmonary blood supply (circulation). During constant metabolism and ventilation, P ET CO2 reflects pulmonary blood perfusion, thus cardiac output (CO). This study aimed at evaluating the correlation between P ET CO2 levels and CO during cardiac surgery with cardiopulmonary bypass (CPB). METHODS: Participated in this study 25 patients submitted to coronary artery bypass grafting (CABG) with CPB. End-tidal CO2 monitoring started after tracheal intubation. Cardiac output was determined by thermodilution with pulmonary artery catheter (Swan-Ganz). Carbon dioxide partial blood pressure (PaCO2) was obtained with arterial blood gases analysis. Studied parameters were evaluated in the following moments: immediately after general anesthesia induction, before cardiopulmonary bypass, at cardiopulmonary bypass completion and at surgery completion. RESULTS: Statistical analysis has not shown correlation between P ET CO2 and CO2, or between P ET CO2-PaCO2 gradient (Ga-eCO2) and CO. There has been correlation between P ET CO2, Ga-eCO2 and CO values variation as compared to baseline values before CPB, with loss of correlation after CPB until surgery completion. CONCLUSIONS: In this study, where patients submitted to cardiac surgery with CPB were evaluated, ventilation/perfusion changes throughout the procedure might have been the factors determining decreased correlation between cardiac output and end tidal CO2.

Keywords

MONITORIZATION, MONITORIZATION, SURGERY

References

MC Hardy GJ. The relationship between the differences in pressure and content of carbon. Clin Sci. 1967;32:299-309.

Teboul JL, Mercat A, Lenique F. Value of the venous-arterial PCO2 gradient to reflect the oxygen supply to demand in humans: effects of dobutamine. Crit Care Med. 1998;26:1007-1010.

Osterlund A, Gideon P, Krill G. A new method of using gas exchange measurements for the non-invasive determination of cardiac output: clinical experiences in adults following cardiac surgery. Acta Anaesthesiol Scand. 1995;39:727-732.

Arnold JH, Stenz RI, Thompson JE. Noninvasive determination of cardiac output using single breath CO2 analysis. Crit Care Med. 1996;24:1701-1705.

Arnold JH, Thompson JE, Arnold LW. Single breath CO2 analysis: description and validation of a method. Crit Care Med. 1996;24:96-102.

Higgins TL, Estafanous FG, Loop FD. Stratification of morbidity and mortality outcome by preoperative risk factors in coronary artery bypass patients: A clinical severity score. JAMA. 1992;267:2344-2348.

Crespo A, Carvalho AF. Capnografia. Monitorização Respiratória em UTI. 1998:283-298.

Opper SE, Fibuch EE, Nelson RE. Effect of oxygenator type and bypass flow pattern on the P(a-ET)CO2 gradient. J Cardiothorac Vasc Anesth. 1992;6:46-50.

Myles PS, Story DA, Higgs MA. Continuous measurement of arterial and end-tidal carbon dioxide during cardiac surgery: Pa-ET CO2 gradient. Anaesth Intensive Care. 1997;25:459-463.

Zia M, Davies FW, Alston RP. Oxygenator exhaust capnography: a method of estimating arterial carbon dioxide tension during cardiopulmonary bypass. J Cardiothorac Vasc Anesth. 1992;6:42-45.

Callaham M, Barton C. Prediction of outcome of cardiopulmonary resuscitation from end-tidal carbon dioxide concentration. Crit Care Med. 1990;18:358-362.

Garnett AR, Ornato JP, Gonzalez ER. End-tidal carbon dioxide monitoring during cardiopulmonary resuscitation. JAMA. 1987;257:512-515.

Falk JL, Rackow EC, Weil MH. End-tidal carbon dioxide concentration during cardiopulmonary resuscitation. N Engl J Med. 1988;318:607-611.

Sanders AB, Kern KB, Otto CW. End-tidal carbon dioxide monitoring during cardiopulmonary resuscitation: A prognostic indicator for survival. JAMA. 1989;262:1347-1351.

Asplin BR, White RD. Out-of-hospital quantitative monitoring of end-tidal carbon dioxide pressure during CPR. Ann Emerg Med. 1994;23:25-30.

Maslow A, Stearns G, Bert A. Monitoring end-tidal carbon dioxide during weaning from cardiopulmonary bypass in patients without significant lung disease. Anesth Analg. 2001;92:306-313.

Isserles AS, Breen PH. Can changes in end-tidal PCO2 measure changes in cardiac output?. Anesth Analg. 1991;73:808-814.

Feng WC, Singh AK. Intraoperative use of end-tidal carbon dioxide tension to assess cardiac output. J Thorac Cardiovasc Surg. 1994;108:991-992.

Hachenberg T, Tenling A, Nystrom SO. Ventilation-perfusion inequality in patients undergoing cardiac surgery. Anesthesiology. 1994;80:509-519.

Chiara O, Giomarelli PP, Biagioli B. Hypermetabolic response after hypothermic cardiopulmonary bypass. Crit Care Med. 1987;15:995-1000.

Wahba RW, Tessler MJ. Misleading end-tidal CO2 tensions. Can J Anaesth. 1996;43:862-866.

Auler Jr JOC, Távora JCF, Miyaji KT. Avaliação não invasiva do débito cardíaco no pós-operatório de cirurgia cardíaca. Rev Bras Anestesiol. 1999;49(^s96).

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