General anesthesia occurs frequently in elderly patients during propofol-based sedation and spinal anesthesia

Autor: Simon C. Mears, Khwaja J. Zakriya, Hochang Lee, Frederick E. Sieber, Allan Gottshalk
Rok vydání: 2008
Předmět:
Zdroj: Journal of clinical anesthesia. 22(3)
ISSN: 1873-4529
Popis: To test the hypothesis that sedation in elderly patients is often electrophysiologically equivalent to general anesthesia (GA).Prospective, observational study.Operating room of a university medical center.40 elderly patients (or=65 yrs of age) undergoing hip fracture repair with spinal anesthesia and propofol-based sedation.In the routine practice group (RP; n = 15), propofol sedation was administered per the usual routine of the anesthesiologist. In the targeted sedation group (TS; n = 25), sedation was titrated to an observer's assessment of alertness/sedation (OAA/S) score of 4 (ie, lethargic in response to name called) to 5 (ie, awake and alert).Both patient groups underwent processed electroencephalographic monitoring using bispectral index (BIS) intraoperatively. BIS levels were compared between groups to determine amount of surgical time spent in GA (BISor= 60).In the RP group, subjects spent 32.2% of surgical time at BIS levels consistent with GA. Although averaged BIS values during surgery increased from (mean +/- SD) 71 +/- 16 to 88 +/- 9 (P0.001), GA was still observed during 5% of surgical time in the TS group. Overall, 13 of 15 (87%) RP group patients and 11 of 25 (44%) TS group patients (P0.010) experienced some period of GA.BIS levels consistent with GA occur frequently in elderly patients during propofol-based sedation for spinal anesthesia. Altering routine practice such that sedation is titrated to a targeted clinically-determined sedation level reduces - but does not eliminate - this incidence.
Databáze: OpenAIRE