Yeungnam Univ J Med.  2019 Jan;36(1):50-53. 10.12701/yujm.2019.00010.

Awareness during general anesthesia despite simultaneous bispectral index and end-tidal anesthetic gas concentration monitoring

• Lee J
• Park C
• Kim S

• KMID: 2434099
• DOI: http://doi.org/10.12701/yujm.2019.00010

Abstract

Awareness during general anesthesia occurs in approximately 0.1-0.2% of cases; nevertheless, particular attention is required because it can lead to critical complications including insomnia, depression, anxiety, and post-traumatic stress disorder. To prevent these complications, bispectral index (BIS) and end-tidal anesthetic gas (ETAG) concentration monitoring are commonly used to examine patient consciousness during surgery. In the present case, an 80-year-old man was scheduled for total gastrectomy. Anesthesia was maintained using desflurane 4.0-5.0% vol, oxygen, and nitrous oxide. The authors simultaneously monitored BIS, which was maintained between 37 and 43, and ETAG, which was maintained between 0.9 and 1.2 minimum alveolar concentration (MAC). After the operation, however, the authors were surprised to learn that the patient complained of awareness during anesthesia. Although BIS and ETAG concentration monitoring are useful in preventing awareness during anesthesia, they cannot be completely trusted. Even though BIS was maintained at approximately 40 and ETAG at 0.7-1.3 MAC, awareness during anesthesia occurred.

Keyword

Anesthesia; Awareness; Consciousness monitors

MeSH Terms

Aged, 80 and over
Anesthesia
Anesthesia, General*
Anxiety
Consciousness
Consciousness Monitors
Depression
Gastrectomy
Humans
Intraoperative Awareness
Nitrous Oxide
Oxygen
Sleep Initiation and Maintenance Disorders
Stress Disorders, Post-Traumatic
Nitrous Oxide
Oxygen

Reference

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