The Effect of Hypotensive Anesthesia on Cognitive Functions in Orthognatic Surgery

NCT ID: NCT06925711

Last Updated: 2025-04-13

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 32 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2022-12-19
• Study Completion Date: 2024-02-19

Brief Summary

The purpose of this study is to evaluate the effects of maintaining adequate cerebral oxygen saturation on patients undergoing orthognathic surgery. Orthognathic surgery is performed to repair anomalies in the maxillofacial skeleton for both aesthetic and functional purposes. During these procedures, controlled hypotensive anesthesia is commonly used to reduce bleeding, improve surgical field visibility, and shorten operation time.

In controlled hypotensive anesthesia, mean arterial blood pressure is deliberately reduced to approximately 55-60 mmHg. While this technique offers surgical advantages, it may potentially reduce cerebral blood flow and oxygen saturation, which could affect cognitive function.

This study will investigate the relationship between cerebral oxygen saturation levels maintained during orthognathic surgery and postoperative neuropsychological outcomes. Patients will undergo cognitive assessments before and after surgery while cerebral oxygen saturation is continuously monitored during the procedure. Our findings will help establish safety parameters for hypotensive anesthesia in orthognathic surgery and potentially contribute to improved anesthesia management protocols that better preserve cognitive function.

Detailed Description

Orthognathic surgery is a surgical procedure performed to repair anomalies in the maxillofacial skeleton. It can be performed for maxillofacial aesthetics as well as for functional purposes. Since orthognathic surgery is performed in a field where vascular structures are dense, complications such as intraoperative bleeding are likely to occur.

Le Fort I osteotomy and bilateral sagittal split ramus osteotomy (BSSRO) are frequently used treatment methods for dentofacial deformities. Significant bleeding may occur especially during Le Fort I osteotomy. Therefore, controlled hypotensive anesthesia is frequently used during maxillofacial surgery procedures to reduce bleeding, increase the visibility of the surgical field, and prevent blood loss.

During controlled hypotensive anesthesia, mean arterial blood pressure (MAP) is reduced to around 55-60 mmHg. This technique makes the operation more comfortable for both the surgical team and the anesthesia team. Vasoactive and anesthetic agents such as direct-acting vasodilators, autonomic ganglion blockers, beta-adrenergic receptor blockers, and calcium channel blockers are used to provide hypotensive anesthesia.

However, prolonged hypotension may lead to organ damage due to hypoperfusion. Uncontrolled prolongation of systemic hypotension may cause cerebral ischemia, neuronal death, and permanent brain damage by causing a decrease in cerebral blood flow. Cerebral circulation has a complex and unpredictable autoregulatory mechanism. Therefore, it is difficult to maintain the balance between hypotension and cerebral perfusion.

Changes in cerebral blood flow and cerebral tissue perfusion may cause cognitive changes because they affect the nutrition of neural tissues. The aim of this study is to evaluate the effects of controlled hypotensive anesthesia applied in orthognathic surgery on intraoperative cerebral blood flow-cerebral oxygen saturation and cognitive functions of patients and to determine the degree of these effects.

As part of the study, cognitive function tests will be performed on the patient population before and after surgery, and cerebral oxygen saturation will be continuously monitored during surgery. The results may help determine the safety limits of hypotensive anesthesia applied during orthognathic surgery and potentially develop cerebral protection strategies.

The results of this research are expected to contribute to the development of new approaches to improve anesthesia management in patients undergoing orthognathic surgery. Additionally, by testing the hypothesis that maintaining cerebral oxygen saturation may improve cognitive outcomes, it can contribute to increasing patient safety in maxillofacial surgical practices.

Conditions

Cognitive Dysfunction; Postoperative Complications

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Patients aged 18 years and older with ASA I-II scores who were diagnosed with dentofacial deformity

Near-Infrared Spectroscopy (NIRS)

Intervention Type: DEVICE

Controlled hypotensive anesthesia during orthognathic surgery with cerebral oxygen saturation monitoring using Near-Infrared Spectroscopy (NIRS). NIRS was used to continuously monitor regional cerebral oxygen saturation (rSO2) throughout the procedure to observe the effects of controlled hypotension on cerebral perfusion

Interventions

Near-Infrared Spectroscopy (NIRS)

Controlled hypotensive anesthesia during orthognathic surgery with cerebral oxygen saturation monitoring using Near-Infrared Spectroscopy (NIRS). NIRS was used to continuously monitor regional cerebral oxygen saturation (rSO2) throughout the procedure to observe the effects of controlled hypotension on cerebral perfusion

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

Patients undergoing Orthognathic surgery under general anesthesia ASA grade ≤ grade III; Patients can communicate normally, can cooperate and complete cognitive function test; Patients volunteered and signed informed consent.

Exclusion Criteria

BMI < 18 or > 27 kg / m2; Previous history of dementia, psychosis or other central nervous system diseases or mental diseases, such as cerebral infarction, stroke, Parkinson's disease, etc; Patients taking sedatives or antidepressants; Alcoholics or drug addicts; Patients with cognitive impairment before operation (MMSE score < 23); Patients with peripheral vascular diseases and contraindication of arterial puncture and catheterization; Patients unable to carry out long-term follow-up or poor compliance.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 50 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Medipol University

OTHER

Sponsor Role: lead

Responsible Party

Tumay Uludag Yanaral

Associate Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Istanbul Medipol University Hospital

Istanbul, , Turkey (Türkiye)

Countries

Turkey (Türkiye)

References

Li X, Zheng Y, Zhang J. Cerebral oxygenation and hemodynamic changes during ephedrine and phenylephrine administration for transient intraoperative hypotension in patients undergoing major abdominal surgery: a randomized controlled trial. BMC Anesthesiol. 2025 Feb 20;25(1):87. doi: 10.1186/s12871-025-02944-z.

Reference Type: BACKGROUND

PMID: 39979813 (View on PubMed)

Hsiao YC, Chang YT, Cheng CS, Lien KH. Dexmedetomidine infusion on blood loss in orthognathic surgery: A retrospective study on its efficacy. J Formos Med Assoc. 2025 Feb 13:S0929-6646(25)00051-8. doi: 10.1016/j.jfma.2025.02.009. Online ahead of print. No abstract available.

Reference Type: BACKGROUND

PMID: 39952888 (View on PubMed)

Ravelo V, Olate S, Bravo-Soto G, Zaror C, Mommaerts M. Systematic review of soft-to-hard tissue ratios in orthognathic surgery: 3D analysis-update of scientific evidence. Int J Oral Maxillofac Surg. 2025 Sep;54(9):819-829. doi: 10.1016/j.ijom.2025.02.008. Epub 2025 Mar 17.

Reference Type: BACKGROUND

PMID: 40102081 (View on PubMed)

Other Identifiers

MEDIPOLU-6143

Identifier Type: -

Identifier Source: org_study_id