End-tidal to arterial carbon dioxide partial pressure difference during craniotomy in anaesthetised patients.
This study to evaluate the relationship between end-tidal carbon dioxide pressure (ETCO2) and arterial partial pressure of carbon dioxide (PaCO2) included 35 patients between the ages of 18 and 65 years, ASA grade 1 and 2, who had elective craniotomies. Measurements of PaCO2 and ETCO2 were taken simultaneously: 1) 10 minutes after induction of general anaesthesia, 2) after cranium opening prior to dural incision, 3) start of dural closure. There was significant correlation between ETCO2 and PaCO2 (correlation coefficient: 0.571, 0.559 and 0.629 respectively). The mean (SD) difference for PaCO2 and ETCO2 were: 3.84 (2.13), 4.85 (5.78) and 3.91 (2.33) mmHg respectively. Although there was agreement, the bias is of significant clinical importance. In conclusion, we find that ETCO2 consistently underestimated the value of PaCO2 during craniotomy.
Department of Anaesthesiology and Intensive Care, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, Cheras, 56000 Kuala Lumpur, Malaysia.
J
J
Husaini
Y C
YC
Choy
D000293:Adolescent; D000328:Adult; D000368:Aged; D000758:Anesthesia / Q000379:methods*; D001158:Arteries / Q000737:chemistry; D001784:Blood Gas Analysis; D019296:Capnography; D002245:Carbon Dioxide / Q000032:analysis / Q000097:blood; D003399:Craniotomy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D010313:Partial Pressure; D011446:Prospective Studies; D055815:Young Adult
D002245:Carbon Dioxide