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  • Print publication year: 2011
  • Online publication date: August 2011

16 - End-tidal carbon dioxide monitoring in postoperative ventilator weaning

from 1 - Ventilation

Summary

Anesthesiologists monitor their patients' breathing by listening to the lungs or auscultating over the trachea, counting the respiratory rate, watching chest movement and tidal volume, and employing pulse oximetry and capnography. This chapter focuses on issues related to capnography specific to anesthesia and the operating room. Capnography is the best monitor to identify complete disconnection of the breathing circuit. Exhaled tidal volume is a sensitive indicator of leaks and partial disconnects during mechanical ventilation. Capnography will continue to detect expired CO2 as long as the patient's exhaled tidal volume passes sidestream or mainstream sampling ports. Patients with chronic obstructive pulmonary disease or asthma exhibit typical capnograms with upsloping expired values brought about by the slow emptying of partially obstructed segments of the lungs. Intermittent PaCO2 determination has been used as a routine parameter for acid-base management during cardiopulmonary bypass (CPB).

References

1. SalamA, SminaM, GadaP, et al. The effect of arterial blood gas values on extubation decisions. Respir Care 2003; 48: 1033–7.
2. SemmesBJ, TobinMJ, SnyderV, GrenvikA. Subjective and objective measurement of tidal volume in critically ill patients. Chest 1985; 87: 577–9.
3. VaghadiaH, JenkinsLC, FordRW.Comparison of end-tidal carbon dioxide, oxygen saturation and clinical signs for the detection of oesophageal intubation. Can J Anaesth 1989; 36: 560–4.
4. CoteCJ, RolfN, LiuMN, et al. A single-blind study of combined pulse oximetry and capnography in children. Anesthesiology 1991; 74: 980–7.
5. ZwernemanK. End-tidal carbon dioxide monitoring: a VITAL sign worth watching. Crit Care Nurs Clin N Am 2006; 18: 217–25.
6. BhendeMS, ThompsonAE, HowlandDF.Validity of a disposable end-tidal carbon dioxide detector in verifying endotracheal tube position in piglets. Crit Care Med 1991; 19: 566–8.
7. JohnsonDC, BatoolS, DalbecR.Transcutaneous carbon dioxide pressure monitoring in a specialized weaning unit. Respir Care 2008; 53:1042–7.
8. AdrogueHJ, RashadMN, GorinAB, YacoubJ, MadiasNE. Assessing acid–base status in circulatory failure: differences between arterial and central venous blood. N Engl J Med 1989; 320: 1312–16.
9. MorleyTF, GiaimoJ, MaroszanE, et al. Use of capnography for assessment of the adequacy of alveolar ventilation during weaning from mechanical ventilation. Am Rev Respir Dis 1993; 148: 339–44.
10. Prause, GH, HetzP, LaudaH, et al. A comparison of the end-tidal CO2 documented by capnometry and arterial PCO2 in emergency patients. Resuscitation 1997; 35: 145–8.
11. Ontario Ministry of Health. Technology Subcommittee of the Working Group on Critical Care, Ontario Ministry of Health. Can Med Assoc J 1992; 146: 703–12.
12. CarlonGC, RayC Jr., MiodownikS, KopecI, GroegerJS. Capnography in mechanically ventilated patients. Crit Care Med 1988; 16: 550–6.
13. YangKL, TobinMJ. A prospective study of indexes predicting the outcome of trials of weaning from mechanical ventilation. N Engl J Med 1991; 324: 1445–50.
14. SauraP, BlanchL, LucangeloU, et al. Use of capnography to detect hypercapnic episodes during weaning from mechanical ventilation. Intens Care Med 1996; 22: 374–81.
15. WithingtonDE, RamsayJG, SaoudAT, BilodeauJ. Weaning from ventilation after cardiopulmonary bypass: evaluation of a non-invasive technique. Can J Anaesth 1991; 38: 15–19.
16. TaskarV, JohnJ, LarssonA, WetterbergT, JohnsonB. Dynamics of carbon dioxide elimination following ventilator resetting. Chest 1995; 8: 196–202.
17. MaslowA, StearnsG, BertA, et al. Monitoring end-tidal carbon dioxide during weaning from cardiopulmonary bypass in patients without significant lung disease. Anesth Analg 2001; 92: 306–13.