Carbon dioxide kinetics and capnography during critical care

C T Anderson, P H Breen, C T Anderson, P H Breen

Abstract

Greater understanding of the pathophysiology of carbon dioxide kinetics during steady and nonsteady state should improve, we believe, clinical care during intensive care treatment. Capnography and the measurement of end-tidal partial pressure of carbon dioxide (PETCO2) will gradually be augmented by relatively new measurement methodology, including the volume of carbon dioxide exhaled per breath (VCO2,br) and average alveolar expired PCO2. Future directions include the study of oxygen kinetics.

Figures

Figure 1
Figure 1
(a) Scheme of carbon dioxide stores and transport. PaCO2, arterial PCO2; PACO2, alveolar PCO2; PETCO2, end-tidal PCO2; V̇A, alveolar ventilation; V̇CO2,ti, tissue carbon dioxide production; V̇D, dead space ventilation; V̇E, expired ventilation; V̇I, inspired ventilation. (b) Normal capnogram (tidal PCO2 versus time). Phase I, inspiratory baseline; Phase II, expiratory upstroke; Phase III, alveolar plateau; and Phase IV, inspiratory downstroke. Adapted from Breen [61].
Figure 2
Figure 2
Effect of alveolar dead space (VDalv). The right lung compartment receives no perfusion and contains no carbon dioxide (ignoring interlung unit ventilation). By mass balance for carbon dioxide, VDalv/VTalv = (PaCO2 - PETCO2)/PaCO2. For the sample condition shown, VDalv/VTalv = (40-20)/40= 50%. PaCO2, arterial PCO2; PACO2, alveolar PCO2; PETCO2, end-tidal PCO2; P CO2, mixed venous PCO2;VTalv, alveolar tidal volume.Adapted from Breen [61].
Figure 3
Figure 3
Hydraulic model of carbon dioxide kinetics in the body. Large peripheral tissue carbon dioxide compartment (left) drains through cardiac output ( T) into the smaller central pulmonary carbon dioxide compartment (right). FCO2, fractional carbon dioxide; FRC, functional residual capacity; PaCO2 arterial PCO2; P CO2, mixed venous PCO2; V̇A/ , ventilation : perfusion ratio; VCO2,ti, tissue carbon dioxide production; VDana, anatomical dead space; V̇E, exhaled ventilation (see text). Adapted from Breen and Mazumdar [3].
Figure 4
Figure 4
Initial breath-by-breath effects of adding 11 cmH2O PEEP in mechanically ventilated anesthetized dogs on carbon dioxide volume exhaled per breath (VCO2,br), end-tidal PCO2 (PETCO2), exhaled tidal volume (VT), and cardiac output (QT, aorta flow probe). PaCO2, arterial PCO2; P CO2, mixed venous PCO2. Adapted from Breen and Mazumdar [3].
Figure 5
Figure 5
In five mechanically ventilated dogs, effect of 70 min of RPA occlusion on the following: (a) carbon dioxide volume exhaled per breath (VCO2,br); (b) PCO2; (c) dead space (VD); (d) ascending aortic cardiac output ( T); and (e) mean pulmonary artery pressure (Ppa). RPA occlusion began after time 0 (baseline). Solid symbol denotes significant difference (P < 0.05) from baseline measurement. *All stages during RPA occlusion were significantly different from baseline. PaCO2, arterial PCO2; PETCO2, end-tidal PCO2; P CO2, mixed venous PCO2; VDalv/VTalv, alveolar dead space : tidal volume fraction; VDphy, physiologic dead space. From Breen et al [55].

References

    1. Breen PH. Carbon dioxide kinetics during anesthesia: pathophysiology and monitoring. Respiration in Anesthesia: Pathophysiology and Clinical Update. Edited by Breen PH. Philadelphia: WB Saunders, Anesthesiology Clinics of North America. 1998;16:259–293.
    1. Breen PH, Mazumdar B, Skinner SC. Comparison of end-tidal PCO2 and average alveolar expired PCO2 during positive end-expiratory pressure. Anesth Analg. 1996;82:368–373.
    1. Breen PH, Mazumdar B. How does positive end-expiratory pressure decrease CO2 elimination from the lung? Respir Physiol. 1996;103:233–242.
    1. Breen PH, Isserles SA, Harrison BA, Roizen MF. Simple, computer measurement of pulmonary VCO2 per breath. J Appl Physiol. 1992;72:2029–2035.
    1. Breen PH, Serina ER. Bymixer provides on-line calibration of measurement of CO2 volume exhaled per breath. Ann Biomed Eng. 1997;25:164–171.
    1. Breen PH, Serina ER, Barker SJ. Measurement of pulmonary CO2 elimination must exclude inspired CO2 measured at the capnometer sampling site. J Clin Monit. 1996;12:231–236.
    1. Cherniack NS, Longobardo GS. Oxygen and carbon dioxide gas stores of the body. Physiol Rev. 1970;50:196–243.
    1. Dang K, Breen PH. Ambulatory capnography. J Respir Care Pract. 1998;Jun/Jul:25–30.
    1. Stock MC. Capnography for adults. Crit Care Clin. 1995;11:219–232.
    1. Rozycki HJ, Sysyn GD, Marshall MK, et al. Mainstream end tidal carbon dioxide monitoring in the neonatal intensive care unit. . Pediatrics. 1998;101:648–653.
    1. McEvedy BA, McLeod ME, Kirpalani H, Volgyesi GA, Lerman J. End tidal carbon dioxide measurements in critically ill neonates: a comparison of side-stream and mainstream capnometers. Can J Anaesth. 1990;37:322–326.
    1. Breen PH, Mazumdar B, Skinner SC. Capnometer transport delay: measurement and clinical implications. Anesth Analg. 1994;78:584–586.
    1. Pascucci RC, Schena JA, Thompson JE. Comparison of a side-stream and mainstream capnometer in infants. Crit Care Med. 1989;17:560–562.
    1. Doyle DJ. Time constant-related capnograph distortion: a theoretical analysis. J Biomed Eng. 1991;13:500–502.
    1. Cardoso MM, Banner MJ, Melker RJ, Bjoraker DG. Portable devices used to detect endotracheal intubation during emergency situations: a review. Crit Care Med. 1998;26:957–964.
    1. Kelly JS, Wilhoit RD, Brown RE, James R. Efficacy of the FEF colorimetric end-tidal carbon dioxide detector in children. Anesth Analg. 1992;75:45–50.
    1. Nakatani K, Yukioka H, Fujimori M, et al. Utility of colorimetric end-tidal carbon dioxide detector for monitoring during prehospital cardiopulmonary resuscitation. Am J Emerg Med. 1999;17:203–206.
    1. Birmingham PK, Cheney FW, Ward RJ. Esophageal intubation: a review of detection techniques. Anesth Analg. 1986;65:886–891.
    1. Vukmir RB, Heller MB, Stein KL. Confirmation of endotracheal tube placement: a miniaturized infrared qualitative CO2 detector. Ann Emerg Med. 1991;20:726–729.
    1. Asplin BR, White RD. Prognostic value of end-tidal carbon dioxide pressures during out-of-hospital cardiac arrest. Ann Emerg Med. 1995;25:756–761.
    1. Liu S-Y, Lee T-S, Bongard F. Accuracy of capnography in nonintubated surgical patients. Chest. 1992;102:1512–1515.
    1. Sanders AB. Capnometry in emergency medicine. Ann Emerg Med. 1989;18:1287–1290.
    1. Falk JL, Rackow EC, Weil MH. End-tidal carbon dioxide concentration during cardiopulmonary resuscitation. N Eng J Med . 1988;318:607–611.
    1. Garnett AR, Ornato JP, Gonzalez ER, Johnson EB. End-tidal carbon dioxide monitoring during cardiopulmonary resuscitation. JAMA. 1987;257:512–515.
    1. Isserles SA, Breen PH. Can changes in end-tidal PCO2 measure changes in cardiac output? Anesth Analg . 1991;73:808–814.
    1. Garnett AR, Gervin CA, Gervin AS. Capnographic waveforms in esophageal intubation: effect of carbonated beverages. Ann Emerg Med. 1989;18:387–390.
    1. Ping STS, Mehta MP, Symreng T. Reliability of capnography in identifying esophageal intubation with carbonated beverage or antacid in the stomach. Anesth Analg. 1991;73:333–337.
    1. Roberts WA, Maniscalco WM. A novel cause of error in capographic confirmation of intubation in the neonatal intensive care unit. . Pediatrics. 1995;95:140–142.
    1. Werman HA, Talcone RE. Glottic positioning of the endotracheal tube tip: a diagnostic dilemna. Ann Emerg Med. 1998;31:643–646.
    1. Mickelson KS, Sterner SP, Ruiz E. Exhaled PCO2 as a predictor of endotracheal tube placement [abstract]. Ann Emerg Med. 1986;15:208–657.
    1. Knapp S, Kofler J, Stoiser B, et al. The assessment of four different methods to verify tracheal tube placement in the critical care setting. Anesth Analg. 1999;88:766–770.
    1. Roberts WA, Maniscalco WM, Cohen AR, Litman RS, Chhibber A. The use of capnography for recognition of esophageal intubation in the neonatal intensive care unit. Pediatr Pulmonol. 1995;19:262–268.
    1. Linko K, Paloheimo M. Capnography facilitates blind nasotracheal intubation. Acta Anesthesiol Belg. 1983;34:117–122.
    1. Bund M, Walz R, Lobbes W, Seitz W. A tube in the pharynx for emergency ventilation. Acta Anaesthesiol Scand. 1997;41:529–530.
    1. Croswell RJ, Dilley DC, Lucas WJ, Van WF. A comparison of conventional versus electronic monitoring of sedated dental patients. . Pediatr Dent. 1995;17:332–339.
    1. Abramo TJ, Wiebe RA, Scott S, Goto CS, McIntire DD. Noninvasive capnometry monitoring for respiratory status during pediatric seizures. . Crit Care Med. 1997;25:1242–1246.
    1. Wright SW. Conscious sedation in the emergency department: the value of capnography and pulse oximetry. Ann Emerg Med. 1992;21:551–555.
    1. Palmon SC, Liu M, Moore LE, Kirsch JR. Capnography facilitates tight control of ventilation during transport. Crit Care Med. 1996;24:608–611.
    1. Link J, Krause H, Wagner W, Papadopoulos G. Intrahospital transport of critically ill patients. Crit Care Med. 1990;18:1427–1429.
    1. Carlon GC, Cole R, Miodownik S, Kopec I, Groeger JS. Capnography in mechanically ventilated patients. Crit Care Med. 1988;16:550–556.
    1. Technology Subcommittee of the Working Group on Critical Care, Ontario Ministry of Health Noninvasive blood gas monitoring: a review for use in the adult critical care unit. Can Med Assoc J. 1992;146:703–712.
    1. Healey CJ, Fedullo AJ, Swinburne AJ, Wahl GW. Comparison of noninvasive measurements of carbon dioxide tension during withdrawal from mechanical ventilation. Crit Care Med. 1987;15:764–768.
    1. Saura P, Blanch L, Lucangelo U, Fernandez R, Mestre J, Artigas A. Use of capnography to detect hypercapnic episodes during weaning from mechanical ventilation. Intensive Care Med. 1996;22:374–381.
    1. Withington DE, Ramsay JG, Saoud AT, Bilodeau J. Weaning from ventilation after cardiopulmonary bypass: evaluation of a non-invasive technique. Can J Anaesth. 1991;38:15–19.
    1. Morley TF, Giaimo J, Maroszan E, et al. Use of capnography for assessment of the adequacy of alveolar ventilation during weaning from mechanical ventilation. Am Rev Respir Dis. 1993;148:339–344.
    1. Prause G, Hetz H, Lauda P, Pojer H, Smolle-Juettner F, Smolle J. A comparison of the end-tidal CO2 documented by capnometry and the arterial pCO2 in emergency patients. . Resuscitation. 1997;35:145–148. doi: 10.1016/S0300-9572(97)00043-9.
    1. White RD, Asplin BR. Out-of-Hospital quantitative monitoring of end-tidal carbon dioxide pressure during CPR. Ann Emerg Med. 1994;23:25–30.
    1. Szaflarski NL, Cohen NH. Use of capnography in critically ill adults. Heart Lung. 1991;20:363–372.
    1. Ward KR, Menegazzi JJ, Zelenak RR, Sullivan RJ, McSwain NE. A comparison of chest compressions between mechanical and manual CPR by monitoring end-tidal PCO2 during human cardiac arrest. Ann Emerg Med. 1993;22:669–674.
    1. Koetter K, Maleck WH. Effectiveness of mechanical versus manual chest compressions in out-of-hospital cardiac resuscitation [letter]. . Am J Emerg Med. 1999;17:210.
    1. Domsky M, Wilson RF, Heins J. Intraoperative end-tidal carbon dioxide values and derived calculations correlated with outcome: prognosis and capnography. Crit Care Med. 1995;23:1497–1503.
    1. Johnson JL, Breen PH. How does positive end-expiratory pressure decrease pulmonary CO2 elimination in anesthetized patients? . Respir Physiol. 1999;118:227–236.
    1. Jardin F, Genevray B, Pazin M, Margairaz A. Inability to titrate PEEP in patient with acute respiratory failure using end-tidal carbon dioxide measurements. Anesthesiology. 1985;62:530–533.
    1. Blanch L, Fernandez R, Benito S, Mancebo J, Net A. Effect of PEEP on the arterial minus end-tidal carbon dioxide gradient. . Chest. 1987;92:451–454.
    1. Breen PH, Mazumdar B, Skinner SC. How does experimental pulmonary embolism decrease CO2 elimination? Respir Physiol. 1996;105:217–224.
    1. Breen PH, Mazumdar B, Skinner SC. Carbon dioxide elimination measures resolution of experimental pulmonary embolus in dogs. . Anesth Analg. 1996;83:247–253.
    1. Chopin C, Fesard P, Mangalaboyi J, et al. Use of capnography in diagnosis of pulmonary embolism during acute respiratory failure of chronic obstructive pulmonary disease. Crit Care Med . 1990;18:353–357.
    1. Stenz RI, Grenier B, Thompson JE, Arnold JH. Single-breath CO2 analysis as a predictor of lung volume in a healthy animal model during controlled ventilation. Crit Care Med. 1998;26:1409–1413.
    1. Arnold JH, Thompson JE, Arnold LW. Single breath CO2 analysis: description and validation of a method. Crit Care Med . 1996;24:96–102.
    1. Blanch L, Fernandez R, Benito S, Mancebo J, Calaf N, Net A. Accuracy of an indirect carbon dioxide Fick method in determination of the cardiac output in critically ill mechanically ventilated patients. . Intensive Care Med. 1988;14:131–135.
    1. Breen PH. Capnography: the science behind the lines. . A.S.A. Annual Refresher Course Lectures. Park Ridge, IL: American Society of Anesthesiologists. 1994;126:1–7.

Source: PubMed

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