Application of intraoperative nerve monitoring for recurrent laryngeal nerves in minimally invasive McKeown esophagectomy

Background Mediastinal lymphadenectomy is of great importance during esophagectomy for esophageal squamous cell carcinoma. However, recurrent laryngeal nerve (RLN) injury is a severe complication caused by lymphadenectomy along the RLN. Intraoperative nerve monitoring (IONM) can effectively identify the RLN and reduce the incidence of postoperative vocal cord paralysis (VCP). Here, we describe the feasibility and effectiveness of IONM in minimally invasive McKeown esophagectomy. Methods A total of 150 patients who underwent minimally invasive McKeown esophagectomy from 2016 to 2020 were enrolled in this study. We divided the patients into two groups: a neuromonitoring group (IONM, n = 70) and a control group (control, n = 80). Clinical data, surgical variables, and postoperative complications were retrospectively analyzed and compared. Results There was no significant difference in baseline data between the two groups. Postoperative VCP occurred in six cases (8.6%) in the IONM group, which was lower than that in the control group (21.3%, P = 0.032). Postoperative pulmonary complications were found in five cases (7.1%) and 14 in the control group (18.8%, P = 0.037). The postoperative hospital stay in the IONM group was significantly shorter than that in the control group (8 vs. 12, median, P < 0.001). The number of RLN lymph nodes harvested in the IONM group was higher than that in the control group (13.74 ± 5.77 vs. 11.03 ± 5.78, P = 0.005). The sensitivity and specificity of IONM monitoring VCP were 83.8% and 100%, respectively. A total of 66.7% of patients with a reduction in signal showed transient VCP, whereas 100% with a loss of signal showed permanent VCP. Conclusion IONM is feasible in minimally invasive McKeown esophagectomy. It showed advantages for distinguishing RLN and achieving thorough mediastinal lymphadenectomy with less RLN injury. Abnormal IONM signals can provide an accurate prediction of postoperative VCP incidence.

Vocal cord paralysis as a presenting sign of autosomal recessive spinocerebellar atrophy type 10

Acquired vocal cord paralysis (VCP) is caused by dysfunction or injury of one or both recurrent laryngeal nerves. Here we report a 41-year-old man with spinocerebellar atrophy, autosomal recessive type 10 (SCAR10) due to an autosomal recessive mutation in the ANO10 gene, with VCP as the presenting symptom. He later developed ataxia and speech disturbance.

Bilateral tapia syndrome after maxillomandibular advancement surgery

Lesions of the hypoglossal and laryngeal nerve, recurrent in its unilateral or bilateral extracranial pathways, cause a motor deficit in the tongue with transient, partial or total loss of speech, which may be associated with mild or severe dysphagia, characterizing Tapia syndrome. This unusual condition is usually related to airway manipulation during anesthetic-surgical surgery, and few cases in the literature are correlated with maxillofacial surgeries, which partly explains the ignorance of this complication by a significant number of professionals. We describe a case report of bilateral Tapia syndrome established after a procedure for maxillomandibular advancement. This is a 55-year-old male patient diagnosed with retrognatism and retromaxillism. The patient underwent a maxillomandibular advancement with nasotracheal intubation. He evolved with bilateral Tapia syndrome, recovering from the signs and symptoms of this complication, being reoperated to correct aesthetic results obtained in the first intervention that was below acceptable, not evolving after this second surgery with the syndrome. We conclude that preventive measures should be taken, such as avoiding sudden movements in the head region and prolonged hyperextension of the neck during surgery, minimizing the trauma of the tracheal cannula on the tissues covering the hypoglossal and recurrent laryngeal nerves.

Characteristics And Prognostic Value of Lymph Node Metastasis Along Recurrent Laryngeal Nerves in Thoracic Esophageal Squamous Cell Carcinoma

Background: Though the value of lymph node (LN) dissection along bilateral recurrent laryngeal nerve (RLN) has been debated and emphasized in recent years in thoracic esophageal squamous cell carcinoma (ESCC). However, the characteristics of nodal metastasis along RLN chain has not been clarified. This study aimed to investigate the characteristics of nodal metastasis along recurrent laryngeal nerves and the influence of these metastasis on the prognosis of thoracic ESCC.Patients and Methods: 339 eligible patients with thoracic ESCC who underwent esophagectomy with a three-field(3-FL) or two-field(2-FL) lymph node dissection from March 2015 to December 2018 were included in this study, consisting of 282 males and 57 females with a mean age of 60.6 years (range,40-80 years). The association of LN metastasis near RLN with clinicopathologic factors and its influence on survival were analyzed. Results: Among the 339 patients, 96 (28.3%) had LN metastasis along bilateral recurrent laryngeal nerves, 76 (22.4%) with positive LNs along right RLN and 47 (13.9%) along the left RLN. There was a significant difference in the metastasis rate between the LNs along right RLN and along the left RLN (P=0.004). The LN metastasis rate along RLN was significantly correlated with primary tumor locations (upper vs middle vs lower: 35.1% vs 30.9% vs 15.6%; P=0.015), tumor invasion depth (T3/T4 vs T1 vs T2: 36.2% vs 15.8% vs 26.2%, P=0.001 ) and degree of differentiation (well vs moderately vs poorly: 9.3% vs 29.3% vs 33.9%; P=0.009), subcarinal and left tracheobronchial lymph node metastasis (positive vs negative:58.1% vs 25.3%, P＜0.001), abdominal LN metastasis (positive vs negative:41.2% vs 24.0%, P=0.003 ), but was not significantly correlated with age, gender and tumor length. The median follow-up time for this study was 34 months. The cumulative 1-, 2- and 3-year overall survival rates were 95.7%, 86.6% and 82.2% in RLN-LN(-) group versus 81.5%, 67.4% and 53.7% in the RLN-LN(+) group, with a significant difference between two group (HR=2.975,95% CI:1.918-4.614, P＜0.01). Conclusions: The lymph node metastasis along RLNs was significantly correlated with primary tumor locations, tumor invasion depth, tumor differentiation, metastasis in the LNs of other stations, and indicate poor prognosis in ESCC.

Recurrent Laryngeal Nerve Preservation Strategies in Pediatric Thyroid Oncology: Continuous vs. Intermittent Nerve Monitoring

(1) Background: Pediatric thyroidectomy is characterized by considerable space constraints, thinner nerves, a large thymus, and enlarged neck nodes, compromising surgical exposure. Given these challenges, risk-reduction surgery is of paramount importance in children, and even more so in pediatric thyroid oncology. (2) Methods: Children aged ≤18 years who underwent thyroidectomy with or without central node dissection for suspected or proven thyroid cancer were evaluated regarding suitability of intermittent vs. continuous intraoperative neuromonitoring (IONM) for prevention of postoperative vocal cord palsy. (3) Results: There were 258 children for analysis, 170 girls and 88 boys, with 486 recurrent laryngeal nerves at risk (NAR). Altogether, loss of signal occurred in 2.9% (14 NAR), resulting in six early postoperative vocal cord palsies, one of which became permanent. Loss of signal (3.5 vs. 0%), early (1.5 vs. 0%), and permanent (0.3 vs. 0%) postoperative vocal cord palsies occurred exclusively with intermittent IONM. With continuous nerve stimulation, sensitivity, specificity, positive and negative predictive values, and accuracy reached 100% for prediction of early and permanent postoperative vocal cord palsy. With intermittent nerve stimulation, sensitivity, specificity, positive and negative predictive values, and accuracy were consistently lower for prediction of early and permanent postoperative vocal cord palsy, ranging from 78.6% to 99.8%, and much lower (54.2–57.9%) for sensitivity. (4) Conclusions: Within the limitations of the study, continuous IONM, which is feasible in children ≥3 years, was superior to intermittent IONM in preventing early and permanent postoperative vocal cord palsy.

Subjective Voice Outcomes in Surgeon Versus Technician-Monitored Recurrent Laryngeal Nerves in Thyroidectomy

Objectives: To compare subjective voice outcomes and postoperative laryngoscopic examination findings of patients with subjective voice complaints between surgeon-monitored and certified technician–monitored thyroidectomies. Methods: Patients who underwent hemithyroidectomy, total thyroidectomy, and completion thyroidectomy using a nerve monitoring system between November 2015 and June 2018 were included in the study. Retrospective chart review was carried out to assess how often patients reported voice changes and to record postoperative flexible laryngoscopic findings of patients when that examination was performed. Data were analyzed using the χ2 test to identify significant differences in outcomes for the 2 groups. Results: A total of 293 procedures was performed among 3 surgeons. Surgeons monitored the nerves in 147 cases and a certified technician monitored the nerves in 146 cases. Subjective voice changes were identified in 11 (7.48%) cases in the surgeon-monitored group and in 20 (13.70%) cases in the technician-monitored group ( P = .084). Among the patients who expressed subjective voice changes, 7 patients were identified with vocal cord hypomobility or immobility in the surgeon-monitored group and 13 patients had an abnormal examination in the technician-monitored group ( P = .234). Conclusions: Subjective voice changes or proven vocal cord mobility problems were not different between surgeon-monitored patients and technician-monitored patients in thyroidectomies.

Respiration

This chapter discusses the respiratory system of giraffes. The respiratory system supplies oxygen, removes of carbon dioxide and produces the airflow needed to make sounds. Giraffes do not have the velocity of airflow through the airways to vibrate vocal cords sufficiently to generate sounds able to be heard by humans but can produce sounds able to be heard by giraffes. Air reaches alveoli for gas exchange through a long trachea, which is relatively narrow (~4 cm in diameter). Dead space volume is large. A short trunk and rigid chest wall reduce the capacity of the thorax and consequently lung volume is small. Respiratory rate is low (~10 min-1), but tidal volume is relatively big, and alveolar ventilation rate (VA; ~60 L min-1) delivers sufficient air despite the large dead space volume. Laryngeal muscles act to prevent food from entering the trachea a process controlled by the (short) superior and (long) inferior (recurrent) laryngeal nerves. Air that has been delivered to alveoli comes into contact with pulmonary artery blood (=cardiac output, Q; ~40 L min-1). The VA: Q ratio is ~1.5 (cf 0.8 in humans). Gas exchange occurs by diffusion. The surface area for diffusion is related to the number of alveoli which increase in number during growth from ~1 billion in a newborn giraffe to 11 billion in an adult. Gas carriage of oxygen and carbon dioxide is a function of erythrocytes which are small (MCV = 12 fL) but numerous (12 × 1012 L-1) and each liter of blood contains ~150 g of hemoglobin.

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.

Frequency of Vocal Cord Paralysis in Thyroidectomy

Back ground: Recurrent laryngeal nerves being adjacent to the thyroid glands are prone to surgical trauma by thyroid surgery done for thyroid disease leading to vocal cord paralysis. Aim: To determine frequency of vocal cord paralysis in thyroidectomy Methodology: This is a descriptive cases series was completed in 6 months [December 4, 2019 till June 4, 2020] at Department ENT, Sir Ganga Ram hospital Lahore. The sample technique used is non-probability consecutive sampling .All 170 patients meeting inclusion criteria were inducted in the study from ENT SGR hospital, Lahore. Results: The mean age of all patients was 39.52±11.30 years with minimum and maximum age as 20 and 60 years. There were 91(53.5%) cases that were 20-40 years old and 79(46.5%) cases were 41-60 years old. There were 62(36.5%) male and 108(63.5%) female cases with higher female to male ratio. In 96(56.5%) cases left side and in 74(43.5%) cases right side was involved. There were 37(21.8%) who had vocal cord paralysis while 133(78.2%) cases did not have vocal cord paralysis. Conclusion: It is concluded that high number of patients i.e. 21.8% had vocal cord paralysis, so in future ENT surgeons should adopt safety measures for prevention of VCP such anatomical considerations of the sensitive area Keywords: ENT, thyroidectomy, complications, vocal cord paralysis