Neoglottic Reconstruction After Total Laryngectomy: Animal Experiment, Anesthesia And Perioperative Care

Objective: laryngeal carcinoma is one of the common malignant tumors in head and neck region. Total laryngectomy still has its irreplaceable position as a treatment for advanced laryngeal and hypopharyngeal carcinoma which is the most basic and most safety procedure.Phonation function was lost permanently after total laryngectomy.There have been a lot of ways to rehabilitate phonation at home and abroad.But an ideal method that reconstruct breathing, swallowing and pronunciation all three functions at the same stage has not yet appeared so far.This study is to explore a new surgical procedure for glottic reconstruction after total laryngectomy by experimental dogs.Methods: in early experiments,13 adult dogs underwent total laryngectomy plus tracheostomy in order to investigate perioperative nursing and rearing. A comparative study was carried out between two kinds of anesthesia to explore a proper anesthesia for total laryngectomy and neo-glottic reconstruction on experimental dogs.After stable anesthesia,skilled care and feeding were possessed, total laryngectomy plus neo-glottic reconstruction started: 7 adult dogs underwent low order tracheotomy and total laryngectomy. Then trachea - pharyngeal anastomosis was formed as a new glottis preliminary.The new abductor, adductor were respectively made of hyoid muscles and pharyngeal constrictor muscles to open and close the glottis.A conventional postoperative care was implemented after surgery.Results: all dogs survived after surgery,minimum survival time:14days; maximum:67days;average:27days.Some dogs died from airway obstruction and asphyxia which due to the displacement of the tracheostomy tube. Some died from aspiration pneumonia.One died from premature detubation. Swallowing recovery:all 7 cases(7/ 7)resumed oral intake.5 cases reachedⅢ°orⅣ°swallowing in 6 ~10 days after surgery. The remaining 2 cases used to beⅠ°orⅡ°in early days after surgery. The two respectively reachedⅢ°in 21th and 22th days by deglutition training. Phonation recovery:4(4/7)rehabilitated phonation.3 of them phonated with a howl for the first time in 9th after surgery while tube-plugging, sound like"ha ha" ,low and thick.Hearing distance: one:15 metres;the other two:6 metres.1 cases could not phonate while tube-plugging after surgery because of mild dyspnea.Granulation blockage in neoglottis was found in 20th after surgery and then was removed. Phonation was recorded the next day.hearing distance:11metres. The remaining three cases suffered breathing obstruction,vomiting,so phonation could not be induced. Respiration recovery:4(4/7)rehabilitated nasal respiration while plugging tracheostoma, and 1 got postoperative decannulation. Plugging was tried from the ninth day after surgery.4 cases could keep on breathing while plugging.There were some reasons that prevent dogs from decannulation:food refusal due to severe bucking;granulation blockage recurrence in neoglottis; long-term complications of cicatricial contracture in neoglottis. 1 case got postoperative decannulation and survived in good health.Conclusion: using hyoid muscles and pharyngeal constrictor muscles can reconstruct a functional glottis after total laryngectomy, restore deglutition, phonation and respiration at the same stage. This new surgical procedure is worth further exploration.The new larynx can not be sustained with the first annulus tracheae only,which brings about postoperative tracheal collapse.The new abductor do work well still.On the other hand,the new adductor doesn't work well,which needs a further technical adjustment.Meaning: to provide a new method with practical value. Vantage: the hyoid is close to the larynx in anatomy,which reconstruct the frame of the larynx. Studies have reported that supraphyoid muscles have electrophysiological characteristics that similar to laryngeal muscles which reconstruct adductor and abductor of the neoglottis and form a functional larynx.Defect:there's some difference between human and canine in anatomy and innervation.Can human being meet the need of surgical reconstruction of laryngeal function? Researches in hyoid muscle anatomy,myoelectricity and physiology must be done before clinical application.If successful,it should be a promising attempt.