Cervical Vagus Nerve Block Prevents Ocularvagal Reflex

Ultrasound-guided Cervical Vagus Nerve Block Prevents Ocularvagal Reflex in Ophthalmic Surgery

In ophthalmic surgery, surgical operations such as pulling certain eye tissues or compressing the eyeball often leads to bradycardia, arrhythmia even cardiac arrest, bradypnea, nausea and vomiting and elevated blood sugar level. The condition is called the ocularvagal reflex (OVR). Traditionally, when the bradycardia or arrhythmia happens, the operation has to be suspended, and atropine or isoproterenol is given intravenously to treat the bradycardia. Vagus nerve block may be an effective way to prevent and alleviate this vagal reflex. However it is difficult to perform the nerve block with anatomical landmark (blind) methods. In this study, the investigators used ultrasound-guided right cervical vagus nerve block to reduce the incidence of the OVR. The researchers hypothesized that low concentrations of lidocaine or ropivacaine can block the right cervical vagus nerve and reduce the incidence of intraoperative OVR. Researchers evaluated the changes of heart rate, blood pressure, oxygen saturation, and airway pressure in patients undergoing high-risk OVR surgery.

Study Overview

• Status: Recruiting
• Conditions: Reflex, Oculocardiac
• Intervention / Treatment: Drug: Bradycardia Treatment; Procedure: Ultrasound guided vagus nerve block

• Study Type: Interventional
• Enrollment (Anticipated): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Chongqing
    • Chongqing, Chongqing, China, 400042
      • Recruiting
      • Daping Hospital, Army Medical University
      • Contact: Qingxiang Mao, Ph.D.; Phone Number: 02368729729; Email: maomaosmmu@126.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 70 years (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Patients received surgeries with high-risk OVR, including the strabismus surgery, the posterior scleral reinforcement, and the insertion of ocular implant.

Exclusion Criteria:

• Those who have pre-existed vocal cord damage before surgery (such as hoarseness, electronic laryngoscopy shows fixed vocal cords or arytenoid cartilage dislocation).
• Those with a history of surgery on the both sides of the neck (eg, thyroidectomy, carotid endarterectomy).
• American Society of Anesthesiologist (ASA) Grade > 3
• Patients with infection at the neck puncture site, or severe coagulation abnormalities before surgery, or a history of local anesthetic allergy, or who have a pacemaker.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Sham Comparator: Control group; Conventional monitor and treatment The surgery is performed after patient is under general anesthesia. If patient's heart rate significantly slows down or bradycardia/arrhythmia happens, the surgeon will be asked to suspend the operation. Meanwhile, atropine (0.01-0.02mg/kg) is given intravenously to increase the heart rate. If atropine fails to increase the heart rate, isoproterenol (1-2 μg/per time) will be given intravenously to increase the heart rate.	Drug: Bradycardia Treatment; If the OVR happens because the surgical stimulation, the operation suspends and atropine (0.01-0.02mg/kg) or isoproterenol (1-2 μg/per time)is given intravenously to increase the heart rate.
Experimental: Nerve block group; After the patient is under general anesthesia, an attending physicians perform the ultrasound-guided cervical vagus nerve block (using a 50mm Braun nerve stimulation needle, and the patients were injected with 10ml of lidocaine or ropivacaine ). Then the operation starts. If patient's heart rate significantly slows down or bradycardia/arrhythmia happens, the surgeon will be asked to suspend the operation. Meanwhile, atropine (0.01-0.02mg/kg) is given intravenously to increase the heart rate. If atropine fails to increase the heart rate, isoproterenol (1-2 μg/per time) will be given intravenously to increase the heart rate. After endotracheal tube is removed, the patient will be followed up for next 24 hours.	Drug: Bradycardia Treatment; If the OVR happens because the surgical stimulation, the operation suspends and atropine (0.01-0.02mg/kg) or isoproterenol (1-2 μg/per time)is given intravenously to increase the heart rate.; Procedure: Ultrasound guided vagus nerve block; Before the operation starts, patients received the ultrasound guided vagus nerve block. A 50mm Braun nerve stimulation needle is guided by the ultrasonic beam to insert into the carotid sheath and 10ml of lidocaine or ropivacaine is injected.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes of heart rate	Changes of heart rate in beat per minute from Baseline	during the operation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes of Blood pressure	Changes of systolic blood pressure in mmHg from Baseline	during the operation
Changes of Peak airway pressure	Changes of Blood pressure in mmHg from Baseline	during the operation
Changes of SpO2	Changes of SpO2 in percentage in mmHg from Baseline	during the operation
Nausea and vomiting in times		24 hours after the operation
Voice changes in grades (0-3)	Changes of Voice changes in grades (0-3) from Baseline. 0 means good, 2 means moderate change of voice, 3 means hoarse voice	24 hours after the operation

Collaborators and Investigators

• Sponsor: Daping Hospital and the Research Institute of Surgery of the Third Military Medical University

Publications and helpful links

General Publications

• Casutt M, Breitenmoser I, Werner L, Seelos R, Konrad C. Ultrasound-guided carotid sheath block for carotid endarterectomy: a case series of the spread of injectate. Heart Lung Vessel. 2015;7(2):168-176.
• Arnold RW, Bond AN, McCall M, Lunoe L. The oculocardiac reflex and depth of anesthesia measured by brain wave. BMC Anesthesiol. 2019 Mar 14;19(1):36. doi: 10.1186/s12871-019-0712-z.

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2021
• Primary Completion (Anticipated): December 31, 2022
• Study Completion (Anticipated): March 31, 2023

Study Registration Dates

• First Submitted: June 20, 2021
• First Submitted That Met QC Criteria: June 26, 2021
• First Posted (Actual): July 6, 2021

Study Record Updates

• Last Update Posted (Actual): February 21, 2022
• Last Update Submitted That Met QC Criteria: February 4, 2022
• Last Verified: February 1, 2022

More Information

Terms related to this study

• Other Study ID Numbers: 2021-55

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No