C-MAC D-Blade vs Macintosh for Postoperative Vocal Cord Evaluation

Comparison of the C-MAC D-Blade Videolaryngoscope and the Macintosh Laryngoscope for Postoperative Vocal Cord Assessment After Thyroidectomy

This study compares two different laryngoscopes-the C-MAC D-Blade videolaryngoscope and the Macintosh direct laryngoscope-for evaluating vocal cord mobility after thyroidectomy. Patients undergo standard anesthesia and intubation with one of the two devices. After surgery, vocal cord function is assessed to identify early postoperative vocal cord impairment. The study aims to determine whether videolaryngoscopy provides a more reliable and less traumatic method for postoperative vocal cord evaluation compared with the traditional Macintosh laryngoscope.

This prospective randomized study evaluates two laryngoscopic techniques used during endotracheal intubation in patients undergoing thyroidectomy. The C-MAC D-Blade videolaryngoscope provides an angulated blade and video-assisted view of the glottis, while the Macintosh laryngoscope represents the traditional direct visualization method. Because postoperative vocal cord impairment is an important early indicator of potential recurrent laryngeal nerve injury after thyroidectomy, accurate assessment immediately after surgery is clinically valuable.

In this study, eligible patients were randomly assigned to intubation using either the C-MAC D-Blade videolaryngoscope or the Macintosh laryngoscope. All procedures were performed under standard anesthesia protocols by experienced anesthesiologists. After extubation and recovery, vocal cord mobility was evaluated using a standardized six-grade scoring system to assess postoperative vocal cord function.

The study compares intubation characteristics, glottic views, optimization maneuvers, hemodynamic responses, and postoperative vocal cord mobility between the two devices. The primary aim is to determine whether videolaryngoscopy offers a more reliable and less traumatic method for postoperative vocal cord evaluation. Secondary objectives include evaluating ease of intubation, maneuver requirements, and perioperative physiological responses. The findings may help guide device selection for airway management in thyroid surgery and improve early detection of recurrent laryngeal nerve dysfunction.

Inclusion Criteria

• Age between 20 and 70 years.
• Height greater than 145 cm.
• Body mass index (BMI) between 20 and 35 kg/m².
• American Society of Anesthesiologists (ASA) physical status
• Scheduled for elective thyroid surgery under general anesthesia.

Exclusion Criteria

• Prior neck surgery or radiotherapy
• Large thyroid mass causing severe anatomical distortion.
• Mouth opening less than 4 cm.
• Short neck less than 6 cm in length.
• Limited head and neck mobility
• Unexpected difficult intubation.
• Known history of recurrent laryngeal nerve injury
• Presence of any neurological disorder.