Assessment Of Vocal Cord Function Research Articles

Fiberoptic Bronchoscope Guided Assessment of Vocal Cord Function Using Bailey's Manoeuvre With an I-Gel Supraglottic Airway Device in Patients Undergoing Thyroid Surgery: An Initial Exploratory Prospective Study.

Fiberoptic Bronchoscope Guided Assessment of Vocal Cord Function Using Bailey's Manoeuvre With an I-Gel Supraglottic Airway Device in Patients Undergoing Thyroid Surgery: An Initial Exploratory Prospective Study.

A Prospective Study Evaluating the Feasibility and Accuracy of Post-operative Laryngeal Ultrasonography (LUSG) in Assessment of Vocal Cord Function After Esophagectomy.

Vocal cord paresis (VCP) is a serious complication after esophagectomy. Conventional diagnosis of VCP relies on flexible laryngoscopy (FL), which is invasive. Laryngeal ultrasonography (LUSG) is non-invasive and convenient. It has provided accurate VC evaluation after thyroidectomy but it is unclear if it is just as accurate following esophagectomy. This prospective study evaluated the feasibility and accuracy of LUSG in VC assessment on day-1 after esophagectomy. Consecutive patients from a tertiary teaching hospital who underwent elective esophagectomy were prospectively recruited. All received pre-operative FL, and post-operative LUSG and FL on Day-1, each performed by a blinded, independent assessor. The primary outcomes were feasibility and accuracy of LUSG in the diagnosis of VCP on Day-1 post-esophagectomy. The accuracy of voice assessment (VA) was analyzed. Twenty-six patients were eligible for analysis. The median age was 70years (66-73). Majority were male (84.6%). Twenty-five (96.2%) received three-phase esophagectomy. Twenty-four (96%) had same-stage anastomosis at the neck. Three (11.5%) developed temporary and one (3.8%) developed permanent unilateral VCP. Overall VC visualization rate by LUSG was 100%; sensitivity, specificity, positive predictive value, negative predictive value (NPV) and accuracy of LUSG were 75.0%, 100%, 100%, 98.0%, 98.1% respectively, and superior to VA. Combining LUSG with VA findings could pick up all VCPs i.e. improved sensitivity and NPV to 100%. LUSG is a highly feasible, accurate and non-invasive method to evaluate VC function early after esophagectomy. Post-operative FL may be avoided in patients with both normal LUSG and voice.

Ultrasound in Airway Management

Clinical application of ultrasound (US) in airway management has continued to expand and evolve over the years. Our narrative aims to provide an updated summary of the role of airway US in current anesthesia practice, based on evidence published in the recent 5 years. Evidence continues to support the use of US in identifying the cricothyroid membrane and tracheal interspace for infraglottic airway access. While US shows potential in improving the accuracy of prediction of difficult airways, no standardized scanning protocol has yet to be created. Other promising clinical applications of airway ultrasound include confirmation of tracheal intubation, choosing of appropriate endotracheal tubes, assessment of vocal cord function, and guiding of upper airway blocks. Ultrasound has numerous advantages: quick, easy to use, accessible, non-invasive, low radiation exposure; and it provides both dynamic and static images with good inter-operator reliability. Improvement in technology has aided the continuous evolution and expansion of the use of US in airway management. Airway US training should be incorporated into the education curriculum of personnel involved in airway management.

A prospective study evaluating the feasibility and accuracy of very early postoperative translaryngeal ultrasonography in the assessment of vocal cord function after neck surgery

BackgroundEarly recognition of postoperative vocal cord palsy enhances postoperative care. Translaryngeal ultrasonography can assess vocal cord function accurately and noninvasively, but it is unclear whether it is feasible or accurate when done immediately after extubation in the recovery room owing to possible interference from laryngeal swelling. This study assessed the feasibility and accuracy of translaryngeal ultrasonography in this setting. MethodsConsecutive patients undergoing neck operations were subjected to translaryngeal ultrasonography and flexible direct laryngoscopy 1 day before and day 7 after thyroidectomy and parathyroidectomy. Translaryngeal ultrasonography was performed early in the recovery room immediately after extubation in the operating room. A standardized assessment protocol was used. Patient parameters were compared between those with assessable and unassessable vocal cords. ResultsSixty-five patients (91 recurrent laryngeal nerves-at-risk) were analyzed after excluding 2 male patients who failed preoperative translaryngeal ultrasonography. Fifty-six patients underwent thyroidectomy and 9 parathyroidectomy. The median age (range) was 57 (46–69); 44 (68%) were women. Sixty-one patients (94%) had assessable bilateral vocal cords on translaryngeal ultrasonography in the recovery room. Translaryngeal ultrasonography in the recovery room findings corresponded completely with day-7 findings on direct laryngoscopy. Long operative time was associated with nonassessable vocal cords on translaryngeal ultrasonography in the recovery room (P = .026). ConclusionVery early postoperative translaryngeal ultrasonography in the recovery room after neck surgery is highly feasible and accurate. Long operative time may hinder the use of translaryngeal ultrasonography in the recovery room.

Ultrasound imaging of the vocal cords in the perioperative period: a useful assessment of vocal-cord function after thyroidectomy

The incidence of vocal cord (VC) dysfunction and recurrent laryngeal nerve (RLN) palsy after thyroid surgery in our centre is quoted between 1% and 2%. Perioperative assessment of VC function is routinely performed for all patients undergoing thyroid surgery. Before operation, this is done using outpatient naso-endoscopy. Before operation, RLN monitoring is undertaken with nerve stimulation and a NIM EMG endotracheal tube (Medtronic). After operation, various techniques are described. In our centre, naso-endoscopy is usually performed 24 h after surgery, which may delay the detection of VC dysfunction. We describe the use of bedside neck ultrasound scanning (USS) in the early assessment of VC function. We report the case of a 35-yr-old female undergoing elective thyroidectomy. Her VC function was checked in the clinic 2 weeks before surgery and was normal. Immediately before anaesthesia, a USS of her neck was performed using a linear array probe that confirmed normal VC function. We used the following tests to assess VC movement: (i) swallowing (maximal VC closure), (ii) sniffing (maximal VC excursion), and (iii) counting from 1 to 10 (movement with speech). Anaesthesia was induced and the patient intubated using a NIM endotracheal tube without neuromuscular block. Continuous nerve monitoring was used throughout. The operation and anaesthetic were uneventful. As soon as the patient had recovered from anaesthesia and could follow instruction, we repeated her neck USS and confirmed normal VC function (Fig 7, Fig 8). Naso-endoscopy at 24 h confirmed the USS findings.Fig 8View Large Image Figure ViewerDownload Hi-res image Download (PPT) Ultrasound imaging of the VC function has been validated against naso-endoscopy in the outpatient setting.1,2 It has several advantages for the assessment of VC function compared with other methods. Firstly, ultrasound scanners are readily available in many theatres and anaesthetists are familiar with their use. We have found imaging VC function to be simple to learn and teach. The cost of performing a scan is low and usually limited to the cost of a sterile probe cover. We have found ultrasound imaging of the neck to be well tolerated and less invasive than naso-endoscopy or direct laryngoscopy. We believe it has a role in detecting VC dysfunction in the immediate postoperative period to highlight patients at risk of respiratory complications. Although we have only used this technique in elective thyroidectomy, it may be useful in other procedures associated with RLN injury (e.g. thoracotomy). The patient consented to perioperative neck USS and publication of her case. 1.Matta IR, Halan KB, Agrawal RH, et al. J Laryngol Voice 2014; 4: 2–52.Cheng SP, Lee JJ, Liu TP, et al. World J Surg 2012; 36: 2509–15

Successful Assessment of Vocal Cord Palsy Before Tracheal Extubation by Laryngeal Ultrasonography in a Patient After Esophageal Surgery

Laryngeal ultrasonography has mainly been performed after tracheal extubation. However, improvements in ultrasound technology now allow assessment of vocal cord function even under conditions of endotracheal intubation. We report herein the use of laryngeal ultrasonography in an endotracheally intubated patient after esophagectomy, which allowed us to make the presumptive diagnosis of bilateral recurrent nerve palsy before tracheal extubation. Our experience suggests that laryngeal ultrasonography may be useful in assessing vocal cord function even in endotracheally intubated patients, although the indications and efficacy remain to be determined.

The Role of Intraoperative Nerve Monitoring (IONM) in Thyroidectomy

Intraoperative nerve monitoring (IONM) gains daily ground, being used during thyroidectomy to help the surgeon identify the recurrent laryngeal nerve (RLN). But its value still remains debatable among endocrine surgeons. In this review article, we aim to present current knowledge on the subject. The MEDLINE/PubMed database was searched for publications with the medical subject heading "Intraoperative Nerve Monitoring (IONM)" and keywords "thyroidectomy," "recurrent laryngeal nerve (RLN)" or "vocal cord paresis or vocal cord paralysis (VCP)." The search was conducted both on basis of the MESH tree and as a text search. We restricted our search to English till July 2012. In this review, we only included 34 articles and abstracts that were available in English. RLN IONM adds a functional dimension to surgery that aids, but does not replace, visual identification. For the time being, intraoperative visual identification of the nerve and preoperative and postoperative laryngoscopic assessment of vocal cord function remain the gold standard of RLN management in thyroid surgery. Whether IONM will become a standard of care or not depends on the familiarization of each surgeon with this technique as well as on the publication of studies involving large series of thyroidectomies, where the evaluation of IONM will have significant statistical power.

Routine use of fibreoptic nasendoscopy for assessment of vocal cord function and anatomy immediately prior to parathyroid and thyroid surgery

Routine use of fibreoptic nasendoscopy for assessment of vocal cord function and anatomy immediately prior to parathyroid and thyroid surgery

A preliminary study of simple voice assessment in a routine clinical setting to predict vocal cord paralysis after thyroid or parathyroid surgery

To determine if a simple assessment of vocal cord function performed in a routine clinical setting can predict vocal cord paralysis on laryngoscopy in patients following thyroid or parathyroid surgery. Prospective observational cohort study of patients undergoing thyroid or parathyroid surgery. Vocal cord function was assessed in terms of an abnormality of voice or cough reported by the patient or detected by the examiner. Laryngoscopy was performed by indirect mirror examination or fibreoptic nasopharyngolaryngoscopy. Examiners included otolaryngology consultants, registrars, senior house officers and a general practitioner with a special interest in otolaryngology. The patient was often examined by a different clinician before and after surgery. Eighty-six patients participated in the study between August 2003 and July 2004. Eleven had a change in their voice postoperatively and one patient had difficulty coughing. Six of these patients had a vocal cord paralysis. A further five apparently asymptomatic patients had a vocal cord paralysis. The positive predictive value of voice assessment for vocal cord paralysis was 55%. In a routine clinical setting where the assessment of vocal cord function is often reported by different clinicians of varying experience at each patient attendance, the assessment of a patient's voice following thyroid or parathyroid surgery is not adequately predictive of vocal cord paralysis on indirect laryngoscopy or fibreoptic nasopharyngolaryngoscopy. Further study is required to determine reasons for this.

Intraoperative neurophysiology testing of the recurrent laryngeal nerve: Plaudits and pitfalls

Electrode-imbedded endotracheal tubes allow continuous intraoperative assessment of vocal cord function when connected to an electromyographic (EMG) response monitor. Whether this device enhances or hinders the identification and preservation of the recurrent laryngeal nerve (RLN) is unclear. The utility of continuous intraoperative neurophysiology testing (INT) of RLNs was evaluated prospectively in 100 patients undergoing 103 thyroid or parathyroid operations, involving 185 RLNs. The initial experience with 93 RLNs was compared with the subsequent 92 RLNs. Overall, 97.8% of RLNs were identified intraoperatively: 1.6% visually only, 2.2% nerve stimulator only, and 94% both. There was 1 transected RLN (1.1%) in each study group. The EMG monitor could not alert the surgeon to prevent these injuries. Overall, there were 14 instances of nonfunction of visually intact RLNs (7.6%), at some point during the operation and 4 resulting in temporary paralysis (2.2%). There were 8 instances of altered RLN function (4.3%) with no altered vocal cord function postoperatively. The nerve stimulator aided dissection of the RLN in 17 instances (9.2%). There were 7 episodes (3.8%) of equipment dysfunction that hampered surgical dissection. Between study groups there was significantly increased use of the nerve stimulator to first identify the location of the RLN before visual confirmation: 4 of 93, initial group versus 25 of 92, latter group (P < .001). INT aids the anatomic identification of the RLN only when a positive EMG response occurs. A negative EMG response can indicate a non-nerve structure, altered function of the RLN, or equipment setup malfunction. INT cannot necessarily prevent RLN transection.

Role of ultrasound in the assessment of vocal cord function in infants and children.

The determination of the cause of stridor in the infant and child is an important directive for the otolaryngologist. The limitations of current clinical diagnostic techniques have provided the impetus for pursuing newer, more practical techniques to diagnose vocal cord paralysis in children. The purpose of this paper is to describe a new technique to image the larynx and determine its role in discerning vocal cord paralysis in children. This study began with an animal study (lamb model) demonstrating that computerized ultrasound can accurately delineate laryngeal anatomy and function. The human protocol included 27 patients (age 1 day to 14 years): 15 with normal larynges and 12 with vocal cord paralysis. Recorded ultrasound studies of these subjects were compiled in a randomly ordered videotape and presented twice and viewed in a blinded manner by four expert raters. Statistical analysis of their readings revealed that ultrasound is a highly accurate technique to document vocal cord paralysis, with a high degree of interrater and intrarater reliability. Beyond the accuracy and consistency of computerized ultrasound, there are many other aspects of this technique that make it clinically attractive. Laryngeal ultrasound is noninvasive, painless, and widely accepted. It is relatively safe, with no radiation exposure and no need for sedation or anesthesia. It is well tolerated by patients and their families. The results are easily displayed and recorded and available for hard copy storage. This investigation should not be interpreted as an endorsement for laryngeal ultrasound as a replacement for endoscopy in children. This work does indicate, however, that ultrasound is a technique that can accurately address the special issue of vocal cord mobility in infants and children. At present, this is the primary use for laryngeal ultrasound, although with additional investigation and sophistication it is likely that ultrasound of the larynx may become useful for other purposes.

Tussometry: An Objective Assessment of Vocal Cord Function

A number of techniques have recently been developed for altering laryngeal function, including structural framework surgery, reinnervation procedures, augmentation of the vocal cords, electrical stimulation, and pharmacologic intervention. The application of such procedures to appropriate disorders would be facilitated by better objective measures of the outcome. This study describes the new technique of tussometry, which investigates the airflow pattern produced during coughing. The value of 1 parameter, peak value time, is shown by a study of 35 vocal cord palsies versus a control, and of 17 vocal cord palsies before and after augmentation, to be an accurate assessment of vocal cord position. The technique is independent of lung function parameters and intraoral pressures. It is truly objective, having an interobserver variation of 0%, and is eminently reproducible, with an intrasubject coefficient of variation of 3.1% to 5.7%. Tussometry is a rapid, noninvasive technique providing inexpensive objective assessment of vocal cord function in the office setting.

Flexible fibreoptic bronchoscopy via the laryngeal mask.

The efficacy of flexible fibreoptic bronchoscopy through the laryngeal mask was investigated in 20 patients under total intravenous anaesthesia with propofol, fentanyl, atropine and suxamethonium. Mask size 4 was used for men and size 3 for women. Ventilation was performed with oxygen in air, FIO2 0.6. The ventilatory pressures were median 18 (9-40) cmH2O (1.8 (0.9-3.9) kPa) before the bronchoscope was inserted. When the tip of the bronchoscope was above the vocal cords the ventilatory pressures increased to 22 (10-43) mmHg (2.2 (1.0-4.2) kPa) (P < 0.001), and when the tip was situated at the mid-tracheal level there was a further increase to 24 (12-50) mmHg (2.4 (1.2-4.9) kPa) (P < 0.001). Maximal gas leakages were median 1 (0-2) l/min-1. PEEP at the mid-tracheal level was 3 (0-7) cmH2O (0.3(0-0.7) kPa). When 15 min of the procedure had elapsed, PaO2 was 232 (112-350) mmHg (30.9 (14.9-46.6) kPa) and PaCO2 39 (33-46) mmHg (5.2(4.4-6.1) kPa). The lowest oxygen saturation was median 98 (96-100)% and the highest end-tidal CO2 34 (24-41) mmHg (4.5(3.2-5.5) kPa). It was easy to examine the laryngeal opening and a good assessment of vocal cord function was allowed when muscle relaxation ceased. We conclude that flexible fibreoptic bronchoscopy through the laryngeal mask is a safe technique provided that total intravenous anaesthesia is used. It is a valuable alternative to flexible bronchoscopy performed with topical anaesthesia.

The use of spectrograms in the evaluation of vocal cord injection.

The utilization of voice spectrography can be an important adjunct to the assessment of vocal cord function by both laryngologists and speech pathologists. It is especially useful in determining the effectiveness of vocal cord Teflon paste injection procedures. Dysphonic characteristics are made visible, and their improvement can be monitored. As such, spectrographic analysis should be considered as a useful tool for the laryngologist.