Can we improve the assessment of discharge readiness?: A comparative study of observational and objective measures of depth of sedation in children.
BACKGROUND
Current recommended discharge criteria might not be rigorous enough to detect residual sedation. This study evaluated the use of the Bispectral Index (BIS monitor), the University of Michigan Sedation Scale (UMSS; i.e., 0-4 observational scale), and a Modified Maintenance of Wakefulness Test (MMWT; visual observation of the time the child is able to stay awake) in assessing return to baseline status.


METHODS
Twenty-nine children sedated for echocardiographic examination were studied. Nurses administered sedatives and monitored and discharged children according to institutional guidelines. Children were monitored with the BIS(R) throughout the study. Trained observers assigned UMSS scores every 10-15 min until revised discharge criteria were met (i.e., UMSS score of 0 or 1, MMWT duration >/= 20 min). The MMWT value was recorded at each observation following the procedure. Subsequently, blinded observers recorded average BIS values for the 5 min before each UMSS observation.


RESULTS
There were moderate correlations between the BIS, MMWT, and UMSS scores (r = 0.68-0.78; P < 0.01). Revised criteria correctly identified children who were awake and alert (BIS value >/= 90) in 88% of the cases. Only 55% of the children had returned to baseline BIS values when discharged by the nurse, compared with 92% when revised criteria were met (P < 0.05). It took longer to meet revised criteria compared with standard criteria (75.3 +/- 76.2 min vs. 16.4 +/- 13.1 min; P = 0.001).


CONCLUSIONS
The incorporation of specific, objective discharge criteria (i.e., UMSS score of 0 or 1, MMWT duration >/= 20 min) may ensure a status closer to baseline (BIS value >/= 90) compared with nursing judgment using standard criteria. However, such assurance may delay the discharge of sedated children.
Malviya
Shobha
S
Department of Anesthesiology, C.S. Mott Children's Hospital, University of Michigan Health Systems, F3900, Box 0211, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109-0211, USA. smalviya@umich.edu
Voepel-Lewis
Terri
T
Ludomirsky
Achiau
A
Marshall
Janelle
J
Tait
Alan R
AR
D000762:Anesthesia Recovery Period; D002648:Child; D002697:Chloral Hydrate; D016292:Procedural Sedation / Q000145:classification*; D004155:Diphenhydramine; D004452:Echocardiography; D006801:Humans; D008874:Midazolam; D010351:Patient Discharge; D011237:Predictive Value of Tests
D002697:Chloral Hydrate; D004155:Diphenhydramine; D008874:Midazolam