Depth of Anaesthesia and Postoperative Cognitive Decline in Patients Undergoing Heart Surgery

NCT01743456 | Completed DMC

• 1 other identifier: KHC11-001
• Study Type: interventional
• Target: 88
• Locations: 1 country
• Sites: 1

Brief Summary

Post-Operative Cognitive Decline (POCD) is common after cardiac surgery and associated with increased morbidity and mortality. The pathophysiology of POCD is only poorly understood. Causes include hypoperfusion, microemboli and the systemic inflammatory response, which result in a reduction of cerebral oxygen delivery. Cerebral oxygenation can be monitored non-invasively by measuring frontal lobe oxygen saturation (rSO2). The bispectral index (BIS) of the electroencephalogram is widely known to measure depth of anaesthesia, and there is a high correlation between BIS, a dimensionless calculated number between 0 and 100, and clinical criteria of sedation. With BIS below 60 recall is extremely low. The investigators demonstrated recently that inappropriately high levels of anaesthesia may be associated with poorer long-term outcomes in cognition after non-cardiac surgery (Ballard et al. 2012). Whether optimisation of the depth of anaesthesia and cerebral oxygenation has an effect on postoperative cognitive function in patients undergoing cardiac surgery is unknown. The investigators hypothesize that the incidence of POCD in elderly patients (\> 65 years old) at 6 weeks is less with mildly deep anaesthesia (BIS 50 +- 10) and optimised rSO2 (interventions when rSO2 drops below 15% of baseline reading) when compared with current practice (BIS blinded anaesthesia, reflecting moderately to highly deep anaesthesia and blinded rSO2 measurements).

Conditions

Cardiac Bypass Surgery in Adult Patients 65 Years and Older; Postoperative Cognitive Dysfunction; Postoperative Delirium

Keywords

Postoperative cognitive dysfunction; Coronary artery bypass graft surgery; Postoperative cognitive improvement; Postoperative delirium

Outcome Measures

Primary Outcomes (1)

• Incidence of postoperative cognitive decline after bypass surgery

  Six weeks after bypass surgery

Secondary Outcomes (4)

• Incidence of postoperative cognitive decline 5 days and 1 year after bypass surgery

  Five days and one year postoperatively

• Difference in degree of postoperative cognitive decline at 5 days, 6 weeks or 1 year after bypass surgery

  5days, 6 weeks or 1 year postoperatively

• Postoperative Delirium

  3-5 days postoperatively

• Postoperative central nervous system and myocardial biochemical markers

  up to 48 hours postoperatively

Study Arms (2)

Current practice (BIS and rSO2 blinded)

NO INTERVENTION

Targeted intra-operative depth of anaesthesia

EXPERIMENTAL

Other: Targeted intra-operative depth of anaesthesia

Interventions

Targeted intra-operative depth of anaesthesia OTHER

The intervention group receives isoflurane at a concentration that results in a BIS value between 40-60 intra-operatively.

Targeted intra-operative depth of anaesthesia

Eligibility Criteria

• Age: 65 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Older Adult (65+)

You may qualify if:

• patients undergoing elective coronary artery bypass graft surgery
• patients at 65 years of age and older

You may not qualify if:

• diseases of the central nervous system including dementia
• inadequate knowledge of English
• a current or past psychiatric illness
• current use of tranquilizers or antidepressants
• severe visual, auditory, or motor handicap

Sponsors & Collaborators

• King's College Hospital NHS Trust: lead

Study Sites (1)

King's College Hospital NHS Foundation Trust

London, Denmark Hill, SE5 9RS, United Kingdom

Location

Related Publications (1)

• Ballard C, Jones E, Gauge N, Aarsland D, Nilsen OB, Saxby BK, Lowery D, Corbett A, Wesnes K, Katsaiti E, Arden J, Amoako D, Prophet N, Purushothaman B, Green D. Optimised anaesthesia to reduce post operative cognitive decline (POCD) in older patients undergoing elective surgery, a randomised controlled trial. PLoS One. 2012;7(6):e37410. doi: 10.1371/journal.pone.0037410. Epub 2012 Jun 15.

  PMID: 22719840 BACKGROUND

MeSH Terms

Conditions

Postoperative Cognitive Complications; Emergence Delirium

Condition Hierarchy (Ancestors)

Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Cognitive Dysfunction; Cognition Disorders; Neurocognitive Disorders; Mental Disorders; Delirium; Confusion; Neurobehavioral Manifestations; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms

Study Officials

• David Green, FRCA, MBA

  King's College Hospital NHS Trust

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 4, 2012
• First Posted: December 6, 2012
• Study Start: January 1, 2014
• Primary Completion: January 1, 2016
• Study Completion: January 1, 2017
• Last Updated: October 22, 2019

Record last verified: 2013-01

Locations

GB (1)