Reflex, Oculocardiac
Conditions
Brief summary
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.
Interventions
PROCEDUREUltrasound 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.
DRUGBradycardia 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.
Sponsors
Daping Hospital and the Research Institute of Surgery of the Third Military Medical University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
16 Years to 70 Years
Healthy volunteers
No
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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes of heart rate | during the operation | Changes of heart rate in beat per minute from Baseline |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Changes of Blood pressure | during the operation | Changes of systolic blood pressure in mmHg from Baseline |
| Changes of Peak airway pressure | during the operation | Changes of Blood pressure in mmHg from Baseline |
| Changes of SpO2 | during the operation | Changes of SpO2 in percentage in mmHg from Baseline |
| Nausea and vomiting in times | 24 hours after the operation | — |
| Voice changes in grades (0-3) | 24 hours after the operation | Changes of Voice changes in grades (0-3) from Baseline. 0 means good, 2 means moderate change of voice, 3 means hoarse voice |
Countries
China
Outcome results
None listed