Reduction of Intraoperative EEG Burst Suppression

Postoperative Delirium Clinical Trial

— BsR  

Official title:

Reduction of Intraoperative EEG Burst Suppression - Test of Efficacy

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03775356
• Other study ID #: BsR
• Status: Completed
• Phase: N/A
• Start date: January 8, 2019
• Est. completion date: December 19, 2020

Study information

• Verified date: September 2020
• Source: Technische Universität München
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Burst suppression (BS) is a not physiological pattern in the electroencephalogram (EEG). BS during general anesthesia is mainly seen as a sign for too deep hypnosis and may increase the risk of postoperative delirium (POD), a disturbance of consciousness arising within 24 hours after surgery. This monocentric, simple masked randomized study aims primarily to investigate, whether particular anesthesiological interventions reduce the occurrence of intraoperative burst suppression. The investigator initiated trial includes 66 patients (male and female) aged ≥ 60 years in two groups (intervention and control group). Secondary aims will be the correlation of burst suppression and mean arterial pressure, concentration of anesthetics and postoperative delirium.

Description:

Intraoperative burst suppression represents a non physiological EEG pattern. According to the literature and scientific knowledge, intraoperative burst suppression patterns might be caused either by hypotension resulting in a reduced cerebral circulation or by an oversedation of anesthetics correlating with a very deep level of hypnosis.

Some publications exist that discuss the occurrence of intraoperative burst suppression especially in elderly people (aged ≥ 60 years) as a predictor of postoperative delirium and postoperative cognitive dysfunction.

None of the studies however was able to prove a causal relationship between burst suppression and postoperative delirium. Contrary it might simply be an epiphenomenon.

Conducting this interventional trail primarily aims to prove whether specific anesthesiological interventions, such as the treatment of intraoperative hypotension in first line and/or the reduction of the concentration of anesthetics in second line, reduce intraoperative burst suppression. Hence it might be possible to investigate a possible casualty between burst suppression and postoperative delirium in a second trial.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 106
• Est. completion date: December 19, 2020
• Est. primary completion date: December 19, 2020
• Accepts healthy volunteers: No
• Gender: All
• Age group: 60 Years and older

Eligibility

Inclusion Criteria:

• Age = 60 years

• Surgical interventions in general anesthesia (volatile or total intravenous anesthesia)

• expected surgery duration = 1h

• American Society of Anesthesiologists (ASA) 1-4

• written informed consent prior to study participation

Exclusion Criteria:

• Neurological or psychiatric disorders

• hearing difficulty

• deafness

• neurosurgical (intra)cranial surgery

• pregnancy

• expected continuous mandatory ventilation after surgery

Related Conditions & MeSH terms

• Burst Suppression
• Delirium
• EEG With Abnormally Slow Frequencies
• Postoperative Delirium
• Vision Disorders

Intervention

Other:
• Treatment of hypotension and/or reduction of anesthetics
The treatment of hypotension can be done by the responsible anesthetist according to the clinical standard operations including any accepted drug typically used in this hospital. The reduction of anesthetics can be done either by reducing the volatile end tidal anesthetics concentration (ETAC) or the infusion rate of propofol.

Locations

Country	Name	City	State
Germany	Klinikum rechts der Isar - Klinik fuer Anaesthesiologie und Intensivmedizin	München	Bayern

Sponsors (1)

Lead Sponsor	Collaborator
Technische Universität München

Country where clinical trial is conducted

Germany, 

References & Publications (4)

Fritz BA, Kalarickal PL, Maybrier HR, Muench MR, Dearth D, Chen Y, Escallier KE, Ben Abdallah A, Lin N, Avidan MS. Intraoperative Electroencephalogram Suppression Predicts Postoperative Delirium. Anesth Analg. 2016 Jan;122(1):234-42. doi: 10.1213/ANE.0000000000000989. — View Citation

Radtke FM, Franck M, Lendner J, Krüger S, Wernecke KD, Spies CD. Monitoring depth of anaesthesia in a randomized trial decreases the rate of postoperative delirium but not postoperative cognitive dysfunction. Br J Anaesth. 2013 Jun;110 Suppl 1:i98-105. doi: 10.1093/bja/aet055. Epub 2013 Mar 28. — View Citation

Sessler DI, Sigl JC, Kelley SD, Chamoun NG, Manberg PJ, Saager L, Kurz A, Greenwald S. Hospital stay and mortality are increased in patients having a "triple low" of low blood pressure, low bispectral index, and low minimum alveolar concentration of volatile anesthesia. Anesthesiology. 2012 Jun;116(6):1195-203. doi: 10.1097/ALN.0b013e31825683dc. — View Citation

Soehle M, Dittmann A, Ellerkmann RK, Baumgarten G, Putensen C, Guenther U. Intraoperative burst suppression is associated with postoperative delirium following cardiac surgery: a prospective, observational study. BMC Anesthesiol. 2015 Apr 28;15:61. doi: 10.1186/s12871-015-0051-7. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Chance of the total, cumulative burst suppression rate.	The total, cumulative burst suppression rate (BSR) corresponds to area under the curve and is defined by the BSR (%) and the absolute duration of BSR (t).	During general anesthesia and within the intervention
Secondary	Burst suppression rate during induction.	Rate of change of the burst suppression rate during induction.	During induction within the intervention
Secondary	Burst suppression rate during maintenance.	Rate of change of the burst suppression ratio during maintenance.	During maintenance within the intervention
Secondary	Mean arterial blood pressure.	Evaluation of the mean arterial blood pressure with positive burst suppression rate.	During burst suppression within general anesthesia
Secondary	Endtidal anesthetic concentration (ETAC) and infusion rate of propofol.	Evaluation of the mean ETAC and infusion rate of propofol.	During burst suppression within the intervention
Secondary	Specific characteristics of the EEG frequency spectrum during burst suppression	Evaluation of specific EEG frequencies differentiating BSR caused by hypotension or oversedation of anesthetics.	During burst suppression within general anesthesia
Secondary	Postoperative delirium.	Screening of the patients regarding a postoperative delirium by a brief confession assessment method (bCAM).	Within the first three postoperative days