The Incidence of Awareness During Anesthesia: A Multicenter United States Study

Duke University, Durham, North Carolina, United States
Anesthesia & Analgesia (Impact Factor: 3.47). 10/2004; 99(3):833-9, table of contents. DOI: 10.1213/01.ANE.0000130261.90896.6C
Source: PubMed


Awareness with recall after general anesthesia is an infrequent, but well described, phenomenon that may result in posttraumatic stress disorder. There are no recent data on the incidence of this complication in the United States. We, therefore, undertook a prospective study to determine the incidence of awareness with recall during general anesthesia in the United States. This is a prospective, nonrandomized descriptive cohort study that was conducted at seven academic medical centers in the United States. Patients scheduled for surgery under general anesthesia were interviewed in the postoperative recovery room and at least a week after anesthesia and surgery by using a structured interview. Data from 19,575 patients are presented. A total of 25 awareness cases were identified (0.13% incidence). These occurred at a rate of 1-2 cases per 1000 patients at each site. Awareness was associated with increased ASA physical status (odds ratio, 2.41; 95% confidence interval, 1.04-5.60 for ASA status III-V compared with ASA status I-II). Age and sex did not influence the incidence of awareness. There were 46 additional cases (0.24%) of possible awareness and 1183 cases (6.04%) of possible intraoperative dreaming. The incidence of awareness during general anesthesia with recall in the United States is comparable to that described in other countries. Assuming that approximately 20 million anesthetics are administered in the United States annually, we can expect approximately 26,000 cases to occur each year.

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Available from: Karen Domino, Apr 08, 2014
    • "There were an additional 46 cases (0.23%) of " possible awareness " and 1,183 cases of " intraoperative dreaming, " which corresponded to 6.04% (Sebel et al., 2004, 836). With respect to the group of 25 patients who had awareness with recall after general anesthesia, almost half described auditory perceptions, and being unable to move or breathe; other descriptions of awareness included anxiety/stress, pain, sensation of the endotracheal tube, and feeling surgery without pain (Sebel et al., 2004, 836). 21. "
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    • "An essential tool for estimating DoA is the analysis of the Electroencephalogram (EEG) signals during surgeries [1]. Existing DoA estimators utilize EEG signal features such as spectrum, complexity and amplitude properties. "
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    • "Molaee-Ardekani et al. showed that phase of modulation related to various delta subbands as very slow, slow, fast, narrow, cumulative slow 1, and cumulative slow 2 deltas with alpha waves had different correlations with depth of anesthesia, and finally they implied that a fast delta subband was the best choice among various delta subbands to correlate with brain activities, and their phase difference changes with DOA [9]. By considering about 0.2% incidence of awareness and its complications in the united states of America (USA) and multiplying this incidence rate by 22 million anesthesia cases annually in the USA [20], we can find out the magnitude of the problem. Finding solution to this problem can be a great motivation to do of this study. "
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