Intubation-induced Decrease in Heart Rate as an Indicator for Intraoperative Bradycardia

Tracheal Intubation-induced Decrease in Heart Rate as an Indicator for Intraoperative Bradycardia During Microlaryngoscopy -a Prospective Observational Trial

This prospective observational study aims to determine, if an tracheal intubation-related decrease in heart rate is associated with intraoperative reflex bradycardia in patients undergoing microlaryngoscopy (MLS) in general anesthesia.

Study Overview

• Status: Completed
• Conditions: Airway Management; Heart Rate; Tracheal Intubation

Detailed Description

Small studies and case series reported precipitous bradycardia or even asystole due to reflex vagal activity during tracheal intubation and/or laryngoscopy attributable to a so called laryngocardiac reflex (reflex bradycardia); however, larger systematic trials are still lacking. For the purpose of MLS, ENT surgeons frequently apply suspension laryngoscopy (Kleinsasser laryngoscope) in order to visualize the glottis and to enable surgery. Severe bradycardia has been reported during MLS that has been suspected to be induced by reflex vagal activity possibly promoted by the superior laryngeal nerve.

It is still unknown, which patients are at risk for relevant intraoperative bradycardia and moreover, which patients might benefit from preemptive measures such as prophylactic application of positive chronotropic drugs like atropine sulfate, epinephrine or glycopyrrolate. Predictive factors for MLS-induced intraoperative bradycardia have not systematically been investigated yet.

In particularly, it is unknown, if patients that present with a preoperative tracheal intubation-related decrease in heart rate have a predisposition for intraoperative reflex bradycardia during MLS.

This prospective observational study aims to determine, if an tracheal intubation-related decrease in heart rate is associated with intraoperative reflex bradycardia in patients undergoing microlaryngoscopy (MLS) in general anesthesia. Moreover, if we find a positive association, we further aim to determine the predictive value of intubation-relatd bradycardia.

• Study Type: Observational
• Enrollment (Actual): 50

Contacts and Locations

Study Locations

• Germany
  • Hamburg, Germany, 20246
    • University Medical Center Hamburg-Eppendorf

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adult patients requiring general anesthesia with tracheal intubation for elective MLS in a tertiary care hospital who consent to participate within the study period.

Description

Inclusion Criteria:

• Patients requiring general anesthesia with tracheal intubation for elective MLS
• Age ≥ 18

Exclusion Criteria:

• Pregnant or breastfeeding women
• Confirmed indications for awake fiberoptic intubation
• Planned endotracheal intubation without deep anesthesia or neuromuscular blocking agents (e.g. awake videolaryngoscopy)
• Patients at risk for pulmonary aspiration who qualify for rapid sequence induction
• Cardiac pacemaker
• Atrial fibrillation
• Denial of consent

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intraoperative decrease of the heart rate	Continuous intraoperative ECG heart rate measurement (sample rate 1000 hz)	1 hour

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intraoperative asystolia	Continuous intraoperative ECG QRS-complex detection (sample rate 1000 hz)	1 hour
Cardiac arrhythmias	Continuous intraoperative ECG arrhythmia detection and labeling (sample rate 1000 hz)	1 hour
Hypotension	Intraoperative blood pressure measurement	1 hour
Adverse cardiocirulatory events	Intraoperative adverse cardiocirulatory events docuimented by the responsible anethetist	1 hour
PACU stay	Length of stay in the postanesthesia care unit (PACU)	8 hours
Application of atropine sulfate	Intraoperative application of atropine sulfate by the responsible anesthetist (yes/no)	1 hour
Application of positive inotropic drugs	Intraoperative application of other positive inotropic drugs such as epinephrine by responsible anesthetist (yes/no)	1 hour
Application of catecholamines or vasoactive drugs	Intraoperative application of catecholamines or vasoactive drugs by responsible anesthetist (yes/no)	1 hour

Collaborators and Investigators

• Sponsor: Universitätsklinikum Hamburg-Eppendorf
• Investigators: Study Chair: Tanja Peters, Universitätsklinikum Hamburg-Eppendorf; Study Chair: Christian Zöllner, MD, Universitätsklinikum Hamburg-Eppendorf; Study Chair: Martin Petzoldt, MD, Universitätsklinikum Hamburg-Eppendorf

Study record dates

Study Major Dates

• Study Start (Actual): November 4, 2021
• Primary Completion (Actual): June 13, 2022
• Study Completion (Actual): June 13, 2022

Study Registration Dates

• First Submitted: November 5, 2021
• First Submitted That Met QC Criteria: December 3, 2021
• First Posted (Actual): December 16, 2021

Study Record Updates

• Last Update Posted (Actual): July 19, 2023
• Last Update Submitted That Met QC Criteria: July 17, 2023
• Last Verified: July 1, 2023

More Information

Terms related to this study

• Keywords: Laryngoscopy; Bradycardia; Microlaryngoscopy
• Additional Relevant MeSH Terms: Pathologic Processes; Heart Diseases; Cardiovascular Diseases; Arrhythmias, Cardiac; Bradycardia
• Other Study ID Numbers: 2021-10378-BO-ff

Drug and device information, study documents

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