Introduction: Vocal cord injuries (VI), postoperative hoarseness (PH), dysphonia (DN), dysphagia (DG) and sore throat (ST) are common complications after general anesthesia; there is actually a lack of consensus to support the proper timing for post-operative laryngoscopy that is reliable to support the diagnosis of laryngeal or vocal fold lesions after surgery and there are no valid studies about the entity of laryngeal trauma in oro-tracheal intubation. Aim of our study is to evaluate the statistical relation between anatomic, anesthesiological and surgical variables in the case of PH, DG or impaired voice register.
Materials and methods: 50 patients (30 thyroidectomies, 8 videolaparoscopic cholecistectomies, 2 right emicolectomies, 2 left emicolectomies, 1 gastrectomy, 1 hemorrhoidectomy, 1 nefrectomy, 1 diagnostic videothoracoscopy, 1 superior right lung lobectomy, 1 appendicectomy, 1 incisional hernia repair, 1 low anterior rectal resection, 1 radical hysterectomy) underwent clinical evaluation and direct laryngoscopy before surgery, within 6 hours, after 72 hours and after 30 days, to evaluate motility and breathing space, phonatory motility, true and false vocal folds and arytenoids oedema. We evaluated also mean age (56.6 ± 3.6 years), male:female ratio (1:1.5), cigarette smoke (20%), atopic comorbidity (17/50 = 34%), Mallampati class (32% 1, 38% 2, 26% 3, 2% 4), mean duration of intubation (159 minutes, range 50 - 405 minutes), Cormack-Lehane score (34% 1, 22% 2, 22% 3, 2% 4), difficult intubation in 9 cases (18%). No complication during the laryngoscopy were registered. We investigated the statistic relationship between pre and intraoperative variables and laryngeal symptoms and lesions.
Results: In our experience, statistically significant relations were found in prevalence of vocal folds oedema in smokers (p < 0.005), self limiting DG and DN in younger patients (p < 0.005) and in thyroidectomy (p < 0.01), DG after thyroidectomy (p < 0.01). The short preoperative use of steroids and antihistaminic to prevent allergic reactions appears not related to reduction or prevention of DN, DG, PH and ST. No statistical relation in incidence of postoperative complications was found for the prolonged intubation, gastro-esophageal reflux, BURP manoeuvre (backward upward right sided pressure) and Mallampati and Cormack-Lehane class more than 2, maintenance with sevoflurane 2% and use of stilet.
Conclusions: Direct laryngoscopy is essential for the detection of arytenoid lesions after orotracheal intubation for general anesthesia. In our opinion, a part of temporary post-operative DN or PH is due to monolateral or bilateral arytenoids oedema, secondary to prolonged or difficult orotracheal intubation, valuable with laryngoscopy 72 hours after surgery. Is necessary to adjunct these complications in the surgical informed consensus scheme.