Intraoperative end-tidal carbon dioxide values and derived calculations correlated with outcome: prognosis and capnography.
OBJECTIVE
To determine how much information concerning resuscitation and outcome is provided by the end-tidal CO2 and derived variables obtained during surgery.


METHODS
Retrospective chart review.


METHODS
Emergency hospital operating room.


METHODS
One hundred critically ill or injured patients requiring major surgery and having a mortality rate of 41%.


METHODS
Standard intraoperative monitoring, including continuous capnography, plus arterial blood gas analyses every 1 to 1.5 hrs during surgery.


RESULTS
There was only a fair correlation between the PaCO2 and end-tidal CO2 (r2 = .14). The mortality rates in these patients were highest in those patients who had the lowest end-tidal CO2 values, the highest arterial to end-tidal CO2 differences, and the highest estimated alveolar deadspace fraction. A persistent end-tidal CO2 of < or = 28 torr (< or = 3.8 kPa) was associated with a mortality rate of 55% (vs. 17% in those patients with a higher end-tidal CO2). The mortality rate was also increased in patients with a persistent arterial to end-tidal CO2 difference of > or = 8 torr (> or = 1.1 kPa) (58% vs. 23%).


CONCLUSIONS
End-tidal CO2 and derived values should be monitored closely in critically ill or injured patients. Efforts should be made--by increasing cardiac output and core temperature and by adjusting ventilation as needed--to maintain the end-tidal CO2 at > or = 29 torr (> or = 3.9 kPa) and the arterial to end-tidal CO2 difference at < or = 7 torr (< or = 1.0 kPa).
Domsky
M
M
Department of Surgery, Detroit Receiving Hospital and University Health Center, MI 48201, USA.
Wilson
R F
RF
Heins
J
J
D000328:Adult; D000368:Aged; D001784:Blood Gas Analysis; D001794:Blood Pressure; D001803:Blood Transfusion; D001944:Breath Tests; D002245:Carbon Dioxide / Q000032:analysis* / Q000097:blood / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D017063:Outcome Assessment, Health Care; D011379:Prognosis; D012151:Resuscitation; D012189:Retrospective Studies; D015996:Survival Rate; D013990:Tidal Volume; D014947:Wounds and Injuries / Q000401:mortality / Q000601:surgery*
D002245:Carbon Dioxide