Bispectral Index Monitoring Can Be an Effective Method to Assess Sedation Levels After Open-Heart Surgery

Document Type : Original Article


Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, IR Iran.


Background: Proper sedation is the main part of patient management in post-cardiac surgery care units. The bispectral index (BIS) monitor is a noninvasive device that can show the sedation level of patients through electroencephalography processing. We aimed to study the role of BIS monitoring to assess sedation levels in patients after cardiac surgery in the post-cardiac surgery care unit.
Methods: This observational prospective cohort study enrolled 110 patients (37 female, mean age: 60 ± 13 y) candidated for open-heart surgery in Rajaie Cardiovascular Medical and Research Center. In the post-cardiac surgery care unit, sedation levels in 55 patients were monitored via BIS monitoring, while in the control group (n = 55), sedation levels were assessed via the Glasgow Coma Scale, the visual analog scale, and hemodynamic parameters. Both groups had the same sedation protocol. The primary endpoint of the study was the frequency of the prescription of analgesics, and the secondary endpoint was the duration of mechanical ventilation, intensive care unit (ICU) stay, and hospital stay. Data were collected and analyzed using SPSS software, version 22.
Results: The results showed a decrease in the consumption of dexmedetomidine, midazolam, and morphine in the BIS group (p < 0.001), but no significant difference was observed in terms of the use of ketorolac and paracetamol (Apotel) (p > 0.05). Also, in the BIS group, the duration of mechanical ventilation (p < 0.001), ICU stay (P < 0.001), and hospital stay (P < 0.001) decreased significantly compared with that in the BIS group.
Conclusions: BIS monitoring decreased the dose of sedative/analgesic drugs in the participants; it can, therefore, be a reliable method to assess sedation levels. (Iranian Heart Journal 2021; 22(1): 49-56)


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