Common occurrence. Significant risk.

  • In high-risk surgery, such as trauma and cardiac surgery, 36–40% of adult patients develop POD2.
  • Risk increases up to 87% depending on the age of patients and the type of surgery3.
  • POD is independently associated with decreased quality of life4.
  • Patients with postoperative delirium have two to four times greater odds of dying in the hospital and up to five times greater odds of dying within six months4-6.
  • Complications from POD include dementia, loss of independence, and poor cognitive and functional outcomes7.

POD takes more resources. Increases costs.

Postoperative delirium consumes more resources and increases costs.6,8

  • Patients with POD have a 50% higher risk for developing any complication in the hospital.6
  • National healthcare cost burden of POD is estimated at $32.9 billion per year, similar to cardiovascular disease and diabetes.8
  • Additional cost for patients with POD can be as high as $20,327.8

Personalize dosing.
Reduce risk of postoperative delirium.

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

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.

Hip fracture repair patients

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. 

BIS™ guided anesthesia

Monitoring with BIS™ technology provides meaningful insights to help you optimize anesthetic dosing to minimize deep sedation that may lead to burst suppression.

Improve outcomes

  • Improve emergence and recovery times15-18
  • Reduce postoperative delirium up to 29%19

Optimized throughput

  • Faster patient throughput due to using less anesthesia which helps reduce recovery time in the OR and PACU20
  • Faster discharge from the PACU helps minimize OR delays18

Clinical Evidence

BIS™ Index Guided anesthesia reduces risk of POD

“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

BIS™ guided targeted light anesthesia (BIS™ 50) reduced incidence of POD and post op neurocognitive complications

“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

Metanalysis shows reduced incidence of POD with pEEG guided anesthesia

“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

Educational Opportunities

  • 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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    2. Swarbrick CJ, Partridge JSL. Evidence-based strategies to reduce the incidence of postoperative delirium: a narrative review. Anaesthesia. 2022;77;suppl 1:92–101.
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