Objective and Perceptual Characteristics of the Voice After Endotracheal Intubation in Head and Neck Surgery

NCT07131800 | Enrolling By Invitation

• 1 other identifier: Klasa8.1-23/209-3;Broj02/013AG
• Study Type: observational
• Target: 180
• Locations: 1 country
• Sites: 1

Brief Summary

Introduction: Possible consequences of endotracheal intubation are post-intubation voice changes. Hypothesis: Endotracheal intubation during head and neck surgery is associated with objective and perceptual voice disorders. Research objective: To investigate the short-term and long-term effects of endotracheal intubation on voice quality during head and neck surgery. Material, subjects, methodology and research design: A prospective observational cohort study that will include patients undergoing surgery and endotracheal intubation lasting up to 3 hours. Adult patients divided into three groups will be included in the research: thyroid surgery, parotid gland surgery and abdominal surgery. Videostroboscopy, perceptual and objective acoustic voice analysis will be recorded before surgery, on the second postoperative day, two weeks and 1 month after surgery. Expected scientific contribution of the proposed research: The scientific contribution would be an understanding of the risk factors and the connection of voice disorders after endotracheal intubation, as well as the ability to determine differences in this risk in patients undergoing different operations.

Conditions

Voice Disorder Due to Iatrogenic Factor; Endotracheal Intubation During Surgery; Thyroid Surgery; Head and Neck Surgery

Keywords

endotracheal intubation; surgery; head and neck; voice disorder; VHI

Outcome Measures

Primary Outcomes (4)

• Subjective analysis of voice changes before and after endotracheal intubation for thyroid surgery, other head and neck surgery and abdominal surgery using Voice Handicap Index (VHI)

  The Voice Handicap Index (VHI) is one of the most frequently used self-assessment scales for voice disorders. The Croatian version was adapted and validated by Bonetti and Bonetti (2013), while Benšić et al. (2024) confirmed normative values for the Croatian language. The scale consists of 30 items divided into three subscales: \- Functional, emotional and physical component. Each item is rated on a 5-point Likert scale (0 = Never, 1 = Almost Never, 2 = Sometimes, 3 = Almost Always, 4 = Always), giving a total score from 0 to 120, with higher scores indicating greater perceived voice handicap. Participants will complete the VHI questionnaire at Baseline (within 7 days before surgery with endotracheal intubation) and at postoperative follow-up time points (Day 1, Week 2, and Week 4). The primary VHI outcome is the change in total score before and after surgery. Units of Measure: • Total score range: 0-120 Method of Administration: • Self-administered paper

  Preoperative (within 7 days before surgery), Postoperative Day 1, Week 2, and Week 4

• Subjective analysis of voice changes before and after endotracheal intubation for thyroid surgery, other head and neck surgery and abdominal surgery using GRBAS Scale (Perceptual Voice Evaluation)

  The perceptual voice assessment (GRBAS) will be conducted by two speech-language pathologists with several years of clinical experience. Each parameter-Grade, Roughness, Breathiness, Asthenia, and Strain-will be scored on a 4-point scale (0 = Normal, 1 = Slight, 2 = Moderate, 3 = Severe). The average of the two evaluators' scores will be taken, and in the case of significant discrepancies, a third evaluator will be consulted to reach consensus. Voice samples will be recorded at baseline and post-intervention at 4 time points total. The primary GRBAS outcome will be the change in the 'Grade' score; secondary analyses will include changes in R, B, A, and S. Units of Measure: • Ordinal scores (0-3) for each parameter

  Time Points: Preoperative (within 7 days before surgery), Postoperative Day 1, Week 2, and Week 4

• Videostroboscopy Evaluation before and after surgery

  Videostroboscopy uses an endoscope containing a built-in video camera and a stroboscope, which records phonation while the vocal cords are being filmed. The recording captures the frequency of vocal cord vibrations during voice production and provides an apparently slow-motion view of these vibrations. In the stroboscopic video, the movements of the vocal cords are slowed down enough to precisely follow their motion. This technique allows detailed observation of the amplitude and symmetry of vibrations, as well as the phase of vocal cord closure during voice production. It facilitates diagnosis of numerous physical problems with the vocal cords, including paresis resulting from injury to the recurrent laryngeal nerve. Evaluations will be performed pre- and post-intervention using a standardized protocol. 2 experienced phoniatrists will independently review the recordings to identify possible pathology in vocal fold motion or structural damage. No formal scoring system will be applied.

  Preoperative (within 7 days before surgery) and Postoperative day 1

• Objective Acoustic and Aerodynamic Voice Analysis - changes in fundamental frequency before and after surgery

  Objective voice evaluation will be performed using selected acoustic and aerodynamic measures. Voice assessment involves recording sustained phonation of the vowel /a/ in a sound-treated room using a calibrated digital recording system. The recordings will be acquired with a high-quality microphone positioned at a fixed distance of 30 cm from the participant's mouth, placed at a 45° angle. The sound signal will be analyzed using the LingWAVES SLP Suite Pro VPR software (WEVOSYS medical technology GmbH, Germany). This software converts the analog voice signal to digital form and processes it to extract relevant voice parameters. Parameters to be evaluated: • Fundamental frequency (F0) in Hz. Physiological reference values: • Fundamental frequency: Female: \~206 Hz, Male: \~120 Hz,

  Time Points: Preoperative (within 7 days before surgery), Postoperative Day 1, Week 2, and Week 4

Secondary Outcomes (4)

• Objective Acoustic and Aerodynamic Voice Analysis - changes in Intensity before and after surgery

  Time Points: Preoperative (within 7 days before surgery), Postoperative Day 1, Week 2, and Week 4

• Objective Acoustic and Aerodynamic Voice Analysis- changes in Jitter before and after surgery

  Time Points: Preoperative (within 7 days before surgery), Postoperative Day 1, Week 2, and Week 4

• Objective Acoustic and Aerodynamic Voice Analysis- changes in shimmer before and after surgery

  Time Points: Preoperative (within 7 days before surgery), Postoperative Day 1, Week 2, and Week 4

• Objective Acoustic and Aerodynamic Voice Analysis- changes in Maximum phonation time before and after surgery

  Time Points: Preoperative (within 7 days before surgery), Postoperative Day 1, Week 2, and Week 4

Study Arms (3)

Patients undergoing thyroid surgery

Patients undergoing scheduled thyroid surgery at the University Hospital Centre Zagreb under general endotracheal anesthesia without preoperative voice disorder regardless of the cause (previous operations or irradiation on the neck, and damage to the recurrent laryngeal nerve (RLN) during thyroidectomy).

Patients undergoing abdominal surgery

Patients undergoing scheduled abdominal surgery at Day surgery of University Hospital Centre Zagreb under general anesthesia without preoperative voice disorder regardless of the cause (previous operations or irradiation on the neck, and damage to the recurrent laryngeal nerve (RLN) during thyroidectomy). This will include laparoscopic abdominal procedures and other minor abdominal procedures done in Day surgery, and will be control group for head and neck surgical procedures.

Patients undergoing other head and neck surgery besides thyroid

Patients undergoing scheduled head and neck surgeries beside thyroid surgery at the University Hospital Centre Zagreb under general endotracheal anesthesia without preoperative voice disorder regardless of the cause (previous operations or irradiation on the neck, and damage to the recurrent laryngeal nerve (RLN) during thyroidectomy).

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients scheduled for elective thyroid, head and neck surgery or abdominal surgery at the University Hospital Centre Zagreb. All eligible patients will be divided into three groups, as follows: patients scheduled for thyroid gland surgery; patients scheduled for some other type of head and neck operation that does not fall to exclusion criteria (parotidectomy, extirpation of congenital neck cyst, etc.); and control group including patients scheduled for operation other than the head and neck region. All operations will be performed by experienced operators with more than 100 annual procedures.

You may qualify if:

• patients scheduled for elective thyroid, head and neck surgery or abdominal surgery
• and 70 years,
• normal preoperative voice status, and
• normal laryngeal status.

You may not qualify if:

• \<18 years in the time of surgery
• history of previous head and neck operation or radiotherapy
• patients scheduled for head and neck operation that can alter acoustic characteristics of the voice (surgery of the nasal cavity, ear surgery, laryngeal surgery, jaw surgery).
• Patients with preoperatively diagnosed pathologic vocal cord findings (nodules, polyps, vocal cord paralysis),
• patients with postoperative injuries of the vocal cords, recurrent and superior laryngeal nerve,
• patients with laryngopharyngeal reflux,
• patients in whom postoperative evaluation of the voice cannot be performed due to uncooperativeness will also be excluded from the study.

Sponsors & Collaborators

• Clinical Hospital Centre Zagreb: lead

Study Sites (1)

University Hospital Centre Zagreb

Zagreb, 10000, Croatia

Location

Related Publications (1)

• Simic I, Curic Radivojevic R, Slipac J, Prgomet D. VOICE CONDITION FOLLOWING SHORT-TERM ENDOTRACHEAL INTUBATION IN HEAD AND NECK SURGERY: STUDY PROTOCOL FOR CLINICAL TRIAL. Acta Clin Croat. 2023 Apr;62(Suppl1):49-54. doi: 10.20471/acc.2023.62.s1.06.

  PMID: 38746618 BACKGROUND

MeSH Terms

Conditions

Voice Disorders

Condition Hierarchy (Ancestors)

Laryngeal Diseases; Respiratory Tract Diseases; Otorhinolaryngologic Diseases; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Ivana Šimić Prgomet, PhD, mag.logoped, Professor log.

  Clinical Hospital Centre Zagreb

  PRINCIPAL INVESTIGATOR

• Drago Prgomet, MD; PhD, Professor

  Clinical Hospital Centre Zagreb

  STUDY DIRECTOR

• Renata Curić Radiovjević, Primarius

  Clinical Hospital Centre Zagreb

  STUDY CHAIR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 3 Months
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Primarius; MD; PhD; FESAIC

Study Record Dates

• First Submitted: July 8, 2025
• First Posted: August 20, 2025
• Study Start: September 25, 2024
• Primary Completion: December 31, 2025
• Study Completion: March 30, 2026
• Last Updated: August 20, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

CR (1)