Association of Optic Nerve Sheath Diameter and Postoperative Delirium

NCT07249047 | Not Yet Recruiting

• 1 other identifier: ONSD & Delirium
• Study Type: interventional
• Target: 300
• Locations: 0 countries
• Sites: N/A

Brief Summary

Postoperative delirium is a sudden and reversible disturbance of mental function, occurring after surgery, characterized by confusion, inattention, and fluctuating mental status, which can manifest as agitation or lethargy. It is a common post-operative complication, especially in older adults, and is associated with longer hospital stays and worse recovery outcomes. Validated delirium screening tools such as the Intensive Care Delirium Screening Checklist (ICDSC) and the Richmond Agitation and Sedation Scale (RASS) are widely used tools to assess delirium. However, the sensitivity of these screening tools can be variable when used in real-world practice and may miss early cases of delirium. The optic nerve sheath is a protective sheath that encloses part of the optic nerve that is located at the back of the eye. Measurement of the optic nerve sheath diameter is usually done using ultrasound to detect increased cranial pressure. Previous studies that have been conducted have shown that increased ONSD may be associated with occurrence of postoperative delirium. The purpose of this study is to determine if there is an association between optic nerve sheath diameter (ONSD) and the occurrence of delirium after surgery. This study will be conducted at the London Health Sciences Centre and will include 300 patients.

Conditions

Postoperative Delirium

Keywords

Post operative delirium; Optic nerve sheath diameter; Anesthesia

Outcome Measures

Primary Outcomes (1)

• Impact of optic nerve sheath diameter on postoperative delirium

  This will be measured by comparing the diameter of the optic nerve sheath to the results of the Intensive Care Delirium Screening Checklist (ICDSC) that will be used to measure delirium in patients. The ICDSC will provide a score of 0-8 for patients. Scores of 4 or higher will be considered to be indicative of postoperative delirium.

  Days 1-3 postoperatively

Secondary Outcomes (4)

• Impact of optic nerve sheath diameter on hospital length of stay

  Days 1-7 postoperatively

• Impact of optic nerve sheath diameter on mortality

  Days 1-7 postoperatively

• Impact of optic nerve sheath diameter on time spent on a ventilator

  Days 1-7 postoperatively

• Impact of optic nerve sheath diameter on the need for re-intubation

  Days 1-7 postoperatively

Study Arms (1)

Optic nerve sheath diameter (ONSD) ultrasound

EXPERIMENTAL

Optic nerve sheath diameter (ONSD) ultrasound to be performed at the following time points: 1. Prior to the start of surgery 2. At the start of cardiopulmonary bypass (CPB) 3. At the end of cardiopulmonary bypass 4. Admission to the ICU 5. 1 hour after ICU admission 6. 6 hours after ICU admission 7. 24 hours after ICU admission 8. Daily until hospital discharge for delirious patients or daily until discharge from the ICU for non-delirious patients. Delirium will be assessed by administering the Intensive Care Delirium Screening Checklist (ICDSC) to patients twice daily until discharge from ICU.

Procedure: Optic nerve sheath diameter (ONSD) ultrasound

Interventions

Optic nerve sheath diameter (ONSD) ultrasound PROCEDURE

Optic nerve sheath diameter (ONSD) ultrasound to be performed to measure diameter of the optic nerve sheath. Administration of the Intensive Care Delirium Screening Checklist (ICDSC) twice daily until discharge from the ICU.

Optic nerve sheath diameter (ONSD) ultrasound

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• A d u l t s ≥ 1 8 y e a r s .
• Scheduled for cardiac surgery requiring cardiopulmonary bypass (CPB) (e.g., Coronary artery bypass graft (CABG), valve, combined procedures, aortic surgery).
• Anticipated postoperative admission to the Cardiac ICU with expected stay \>48 hours.
• Preoperative ability to undergo ocular ultrasound examination (closed-eyelid scanning).
• Provided informed consent to participate in this study.

You may not qualify if:

• Known or suspected open-globe injury, penetrating ocular trauma, or intraocular foreign body.
• Recent ocular surgery or intravitreal intervention within the past 6 weeks (if surgeon advises against periocular pressure).
• Ocular conditions that invalidate ONSD measurement (e.g., severe proptosis, advanced optic neuropathies, orbital tumors) or obstruct ultrasound window (extensive periocular dressings, severe periorbital edema).
• Known intracranial pathology expected to significantly alter baseline ONSD (e.g., large mass lesion with midline shift, obstructive hydrocephalus) or presence of external ventricular drain at baseline.
• Severe facial trauma or unstable cervical spine precluding safe positioning for ocular ultrasound.
• P r e g n a n c y .
• Inability to perform serial ONSD assessments at scheduled timepoints (e.g., continuous prone positioning) despite reasonable accommodations.
• Enrollment in a conflicting interventional trial that mandates deviations from delirium assessment or ONSD protocol.
• Inability to communicate in the English language.

Sponsors & Collaborators

• London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's: lead

Related Publications (17)

• Mattimore D, Fischl A, Christophides A, Cuenca J, Davidson S, Jin Z, Bergese S. Delirium after Cardiac Surgery-A Narrative Review. Brain Sci. 2023 Dec 7;13(12):1682. doi: 10.3390/brainsci13121682.

  PMID: 38137130 BACKGROUND

• Koster S, Hensens AG, Schuurmans MJ, van der Palen J. Consequences of delirium after cardiac operations. Ann Thorac Surg. 2012 Mar;93(3):705-11. doi: 10.1016/j.athoracsur.2011.07.006. Epub 2011 Oct 10.

  PMID: 21992939 BACKGROUND

• Mangusan RF, Hooper V, Denslow SA, Travis L. Outcomes associated with postoperative delirium after cardiac surgery. Am J Crit Care. 2015 Mar;24(2):156-63. doi: 10.4037/ajcc2015137.

  PMID: 25727276 BACKGROUND

• Chen H, Mo L, Hu H, Ou Y, Luo J. Risk factors of postoperative delirium after cardiac surgery: a meta-analysis. J Cardiothorac Surg. 2021 Apr 26;16(1):113. doi: 10.1186/s13019-021-01496-w.

  PMID: 33902644 BACKGROUND

• van Eijk MM, van den Boogaard M, van Marum RJ, Benner P, Eikelenboom P, Honing ML, van der Hoven B, Horn J, Izaks GJ, Kalf A, Karakus A, Klijn IA, Kuiper MA, de Leeuw FE, de Man T, van der Mast RC, Osse RJ, de Rooij SE, Spronk PE, van der Voort PH, van Gool WA, Slooter AJ. Routine use of the confusion assessment method for the intensive care unit: a multicenter study. Am J Respir Crit Care Med. 2011 Aug 1;184(3):340-4. doi: 10.1164/rccm.201101-0065OC. Epub 2011 May 11.

  PMID: 21562131 BACKGROUND

• Devlin JW, Skrobik Y, Gelinas C, Needham DM, Slooter AJC, Pandharipande PP, Watson PL, Weinhouse GL, Nunnally ME, Rochwerg B, Balas MC, van den Boogaard M, Bosma KJ, Brummel NE, Chanques G, Denehy L, Drouot X, Fraser GL, Harris JE, Joffe AM, Kho ME, Kress JP, Lanphere JA, McKinley S, Neufeld KJ, Pisani MA, Payen JF, Pun BT, Puntillo KA, Riker RR, Robinson BRH, Shehabi Y, Szumita PM, Winkelman C, Centofanti JE, Price C, Nikayin S, Misak CJ, Flood PD, Kiedrowski K, Alhazzani W. Clinical Practice Guidelines for the Prevention and Management of Pain, Agitation/Sedation, Delirium, Immobility, and Sleep Disruption in Adult Patients in the ICU. Crit Care Med. 2018 Sep;46(9):e825-e873. doi: 10.1097/CCM.0000000000003299.

  PMID: 30113379 BACKGROUND

• Robba C, Santori G, Czosnyka M, Corradi F, Bragazzi N, Padayachy L, Taccone FS, Citerio G. Optic nerve sheath diameter measured sonographically as non-invasive estimator of intracranial pressure: a systematic review and meta-analysis. Intensive Care Med. 2018 Aug;44(8):1284-1294. doi: 10.1007/s00134-018-5305-7. Epub 2018 Jul 17.

  PMID: 30019201 BACKGROUND

• Dubourg J, Javouhey E, Geeraerts T, Messerer M, Kassai B. Ultrasonography of optic nerve sheath diameter for detection of raised intracranial pressure: a systematic review and meta-analysis. Intensive Care Med. 2011 Jul;37(7):1059-68. doi: 10.1007/s00134-011-2224-2. Epub 2011 Apr 20.

  PMID: 21505900 BACKGROUND

• Shirodkar CG, Munta K, Rao SM, Mahesh MU. Correlation of measurement of optic nerve sheath diameter using ultrasound with magnetic resonance imaging. Indian J Crit Care Med. 2015 Aug;19(8):466-70. doi: 10.4103/0972-5229.162465.

  PMID: 26321806 BACKGROUND

• Steinborn M, Fiegler J, Ruedisser K, Hapfelmeier A, Denne C, Macdonald E, Hahn H. Measurement of the Optic Nerve Sheath Diameter in Children: Comparison Between Transbulbar Sonography and Magnetic Resonance Imaging. Ultraschall Med. 2012 Dec;33(6):569-573. doi: 10.1055/s-0031-1273491. Epub 2011 Aug 25.

  PMID: 21870318 BACKGROUND

• Zhi H, Cui X, Zhang F, Wang S, Liang X, Wang B, Cui J, Li Y. [Bedside ultrasound monitoring of optic nerve sheath diameter is a predictive factor for 28-day coma, delirium and death in etiologically diverse critically ill patients]. Zhonghua Wei Zhong Bing Ji Jiu Yi Xue. 2024 Oct;36(10):1088-1094. doi: 10.3760/cma.j.cn121430-20230511-00362. Chinese.

  PMID: 39586729 BACKGROUND

• Kaynar A, Komurcu O, Bahsi E, Aydin AO, Karal IH, Akyurt D, Tulgar S, Suren M. Optic nerve sheath diameter is associated with postoperative delirium in patients undergoing open heart surgery. BMC Anesthesiol. 2025 Jul 1;25(1):309. doi: 10.1186/s12871-025-03194-9.

  PMID: 40596877 BACKGROUND

• Mount CA, Das JM. Cerebral Perfusion Pressure. 2023 Apr 3. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Available from http://www.ncbi.nlm.nih.gov/books/NBK537271/

  PMID: 30725956 BACKGROUND

• Peduzzi P, Concato J, Kemper E, Holford TR, Feinstein AR. A simulation study of the number of events per variable in logistic regression analysis. J Clin Epidemiol. 1996 Dec;49(12):1373-9. doi: 10.1016/s0895-4356(96)00236-3.

  PMID: 8970487 BACKGROUND

• Vittinghoff E, McCulloch CE. Relaxing the rule of ten events per variable in logistic and Cox regression. Am J Epidemiol. 2007 Mar 15;165(6):710-8. doi: 10.1093/aje/kwk052. Epub 2006 Dec 20.

  PMID: 17182981 BACKGROUND

• Yang H, Zhang L, Huang P, Luo Y. [Investigation of intracranial pressure in intensive care unit patients with delirium assessed by bedside ultrasound]. Zhonghua Wei Zhong Bing Ji Jiu Yi Xue. 2022 Jun;34(6):635-639. doi: 10.3760/cma.j.cn121430-20220523-00504. Chinese.

  PMID: 35924521 BACKGROUND

• Mowafy SMS, Bauiomy H, Kohaf NA, Abd Ellatif SE. The Role of Ultrasonographic Assessment of Optic Nerve Sheath Diameter in Prediction of Sepsis-Associated Encephalopathy: Prospective Observational Study. Neurocrit Care. 2025 Aug;43(1):308-317. doi: 10.1007/s12028-024-02187-9. Epub 2025 Jan 15.

  PMID: 39815108 BACKGROUND

MeSH Terms

Conditions

Emergence Delirium

Interventions

High-Energy Shock Waves

Condition Hierarchy (Ancestors)

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

Intervention Hierarchy (Ancestors)

Ultrasonic Waves; Sound; Radiation, Nonionizing; Radiation; Physical Phenomena

Study Officials

• Mauricio Giraldo, MD

  London Health Sciences Centre

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Mauricio Giraldo, MD

CONTACT

5196858500; mauricio.giraldo@lhsc.on.ca

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Anesthesiologist, Assistant Professor

Model Details: Optic nerve sheath diameter (ONSD) ultrasound

Study Record Dates

• First Submitted: November 17, 2025
• First Posted: November 25, 2025
• Study Start: February 1, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 31, 2027
• Last Updated: December 23, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share