Immobilités laryngées unilatérales après chirurgie de la glande thyroïde

The circumstances in which recurrent laryngeal nerve palsy occurs after surgery for benign thyroid disease: a retrospective study of 1026 patients

OBJECTIVE

To evaluate the circumstances in which recurrent laryngeal nerve palsy occurs after thyroid surgery.

METHODS

This study assessed 1026 patients who underwent surgery for benign thyroid disease over a seven-year period in a retrospective, single-centre study.

RESULTS

With a total of 1835 recurrent laryngeal nerves at risk, there were 38 cases (2.07 per cent) of transient recurrent laryngeal nerve palsy and 8 (0.44 per cent) of permanent recurrent laryngeal nerve palsy. No explanation was found for 10 of the 46 cases of recurrent laryngeal nerve palsy. Among the 38 other cases, the probable causes included poor identification of the recurrent laryngeal nerve during surgery, involuntary resection of the nerve and several other factors.

CONCLUSION

Apart from accidental resection of the recurrent laryngeal nerve during thyroid surgery, the causes of post-operative recurrent laryngeal nerve palsy are often unclear and likely multifactorial. Poor identification of the recurrent laryngeal nerve during surgery is still the main cause of post-operative recurrent laryngeal nerve palsy, even when intra-operative neuromonitoring is used.

Characteristics, natural evolution and surgical treatment outcomes of unilateral laryngeal paralysis versus ankylosis: A longitudinal cohort study

AIMS

Although unilateral laryngeal immobility (ULI) can results from paralysis or ankylosis of the cricoarytenoid joint, no comparative study exists to date. Aim of this study was to compare clinical features, aetiologies, spontaneous recovery and evolution after surgical treatment of ULI according to its mechanism.

METHODOLOGY

Longitudinal observational cohort study between 1992 and 2017 in a tertiary care referral centre and university teaching hospital. All adult patients with isolated ULI were included. Presenting symptoms and demographic data were recorded at baseline. During follow-up, natural recovery and, if a surgical treatment was performed, treatment failure rate were noted.

RESULTS

994 patients were included, 56.4% of male and with a mean age of 58 years. Overall, 91% had paralysis and 9% had ankylosis. Dysphonia was the main symptom in both groups (>96%). Dyspnoea was more frequent in patients with ankylosis (26.1% vs 4.2% in those with paralysis) whereas dysphagia was more frequent in those with paralysis (31.1% vs 20% in those with ankylosis). With a mean follow-up of 2.3 years (±5.1), spontaneous recovery did not differ according to ULI's aetiology (hazard ratio 1.43, 95% confidence interval 0.85-2.40). Overall, 37.1% underwent a surgical treatment, and paralysis was associated with a lower odd of treatment failure (hazard ratio 0.27, 95% confidence interval 0.10-0.70) over a mean follow-up of 3.1 years (±4.1).

CONCLUSION

ULI resulting from paralysis or ankylosis differ in their symptoms and responses to surgical treatment, whereas natural evolution was similar.

Incidence of Dysphonia and Dysphagia Exceeds Recurrent Laryngeal Nerve Injury During Thyroid Surgery

OBJECTIVES

To determine the prevalence of separate and combined voice and swallowing impairments before and after total thyroidectomy and to delineate risk factors for these symptoms.

METHODS

Retrospective review of 592 consecutive patients who underwent total thyroidectomy from July 2003 to August 2015.

RESULTS

Combined voice and swallowing problems occurred preoperatively in 4.7% (11/234), 3.3% (3/92), and 6.0% (16/266) of patients with malignancy, hyperthyroidism, and benign euthyroid disease, respectively. Postoperatively, prevalence was 5.1%, 2.2%, and 1.9%, respectively. Benign euthyroid disease (20.7%) had the greatest risk of preoperative dysphagia (P = 0.003) and the largest glands (P < 0.001). Comparing before and after surgery, the cancer and benign euthyroid groups had decreased dysphagia (cancer: 11.5% vs. 6.0%, P = 0.034; benign: 20.7% vs. 3.8%, P < 0.001) but increased dysphonia (cancer: 19.2% vs. 28.6%, P = 0.017; benign: 15.8% vs. 27.1%, P = 0.002). Overall, 23/592 (3.9%) developed new dysphagia and 122/592 (20.6%) developed new dysphonia after surgery. Intraoperative recurrent laryngeal nerve transection occurred in 12 cases (2.0%).

CONCLUSIONS

Total thyroidectomy resolved dysphagia but increased dysphonia in benign and malignant euthyroid patients. Voice and swallowing problems following thyroidectomy occurred more frequently than intraoperative recurrent laryngeal nerve transection, confirming symptoms often occur in the absence of suspected nerve injury.

A proposal for thyroid surgery: criteria to identify the references of endocrine surgery

Indicators of effectiveness and quality of care are needed to improve the outcomes in many surgical fields. International and national studies in thyroid surgery have not clearly documented an association between number of cases and outcome quality, but it is essential for the figure of a highly experienced surgeon, able to provide proof of positive outcomes. Therefore, we try to underline the structural and technical requirements in thyroid surgery. Moreover, the need for an accreditation program is outlined.

Complications after total thyroidectomy

The two most common early complications of thyroid surgery are hypocalcemia (20-30%) and recurrent laryngeal nerve injury (5-11%). Bilateral recurrent nerve paralysis resulting in adduction of the vocal cords is a rare life-threatening complication (occurring in less than 0.1% of cases that requires emergency management. Prevention of complications depends on careful operative technique and is enhanced for some teams by the use of specific techniques such as intraoperative neuromonitoring. Postsurgical hypocalcemia is managed by the administration of calcium plus vitamin D for at least 10 days. Recurrent laryngeal nerve paralysis recovers in most cases, and no invasive therapy should be performed for at least six months, except for emergency presentations; laryngeal surgery techniques may offer significant improvement if phonation or respiratory sequelae persist beyond six months, but the results are inconsistent. There should be a systematic strategy for detection of complications after thyroidectomy involving a multidisciplinary approach.