Postoperative delirium consumes more resources and increases costs.6,8
In high-risk surgery,
36–40% OF ADULT PATIENTS DEVELOP POD.2
Patients with POD have
2–4×GREATER ODDS OF DYING in the hospital.4,6
Patients with POD can have
ADDITIONAL COSTS AS HIGH AS $20,327.8
POD IS PREVENTABLE IN UP TO 40% OF CASES.2
Fortunately, postoperative delirium is preventable in up to 40% of cases with a proper screening program, the identification of risk factors, and the implementation of evidence-based monitoring methods within the OR.2
One of the tools that may help minimize risk of postoperative delirium is a direct measurement of the anesthetic effect on your patient’s brain.9 Using pEEG guidance has been shown to be highly sensitive with reduced incidence of POD.10
With its validated algorithm, BIS™ technology accurately reflects the anesthetic effect on your patient’s brain, so you can personalize dosing throughout a procedure to help avoid going too deep, which may lead to burst suppression.
Cardiovascular surgery patients may be at increased risk for postoperative delirium.11
Reducing the risk of postoperative delirium via BIS™-guided anesthesia in cardiac surgery patients
Soehle 2015 - Soehle et al.12 prospectively recorded pre-, intra, and postoperative EEG variables (BIS™ brain monitoring, EEG asymmetry, and burst suppression) via a bilateral BIS™ monitor in 81 cardiac surgery patients. Postoperatively, patients were screened for delirium via the CAM-ICU. Patients who were identified with delirium had a significantly longer duration of burst suppression.
Increased risk for postoperative delirium has been documented in elderly patients undergoing hip fracture repair.13
A study by Sieber et al showed that BIS-guided anesthesia may reduce the risk of postoperative delirium in hip fracture repair surgical patients
Sieber 2010 - Sieber et al.14 Elderly patients undergoing hip fracture repair (n=114) under propofol sedation with spinal anesthesia were randomized to receive either deep (BIS™ index values≈50) or light (BIS™ index values ≥80) sedation. Postoperative delirium was assessed after the second day postoperatively. The light sedation group had a 50% reduction in delirium compared to the deep sedation group.
Monitoring with BIS™ technology provides meaningful insights to help you optimize anesthetic dosing to minimize deep sedation that may lead to burst suppression.
“We found that BIS™ monitoring of the depth of anesthesia prevented POD, whereas EEG monitoring was not effective. BIS™ quantifies the depth of anesthesia based on EEGs, which enables a more accurate control of anesthetic concentration and increases patient safely.”21
- Xia Li et al, Effects of perioperative interventions for preventing postoperative delirium
“Targeting BIS™ 50 resulted in a 34% relative reduction in patients suffering an episode of POD, an absolute reduction of 9% when compared with targeting BIS™ 35. Patients with an episode of POD had more unplanned ICU admissions, stayed 2 days longer in hospital, had a higher incidence of myocardial infarction, were more likely to have impaired cognitive function on the MMSE at discharge and the AMTS score at 30 days and one yr.”22
- Liz Evered et al, Anaesthetic depth and delirium after major surgery: a randomized clinical trial
“Our primary analysis demonstrated a highly sensitive result with a pooled analysis of trials in which the intervention group adhered to manufacturer’s recommended guidelines showing reduced incidence of POD with pEEG guidance.”10
- Matthew Sumner et al, Processed electroencephalography-guided general anaesthesia to reduce postoperative delirium: a systematic review and meta-analysis
The BIS™ monitoring system should not be used as the sole basis for diagnosis or therapy and is intended only as an adjunct in patient assessment. Reliance on the BIS™ monitoring system alone for intraoperative anesthetic management is not recommended.
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