Influencia de las técnicas de hemostasia quirúrgica y la neuromonitorización intraoperatoria en la incidencia de eventos adversos en cirugía de tiroides

Training in intraoperative neuromonitoring of recurrent laryngeal nerves reduces the risk of their injury during thyroid surgery

INTRODUCTION

Even though incidence of recurrent laryngeal nerve palsy (RLNP) is low, it affects importantly the quality of life of patients and remains one of main medicolegal litigation problems in surgery. Intraoperative neuromonitoring (IONM) has become widely accepted tool helping in recurrent laryngeal nerve identification, however no clear association of IONM with RLNP rate has been demonstrated. The aim of our study was to assess whether training in IONM influences rates of RNLP after thyroid surgery as an independent factor.

MATERIAL AND METHODS

We analysed retrospectively 1235 patients who underwent thyroidectomy at the 1st Department of General and Endocrine Surgery, Medical University of Bialystok. Possible risk factors for RLNP were evaluated: application or not of IONM, the extent of surgery or thyroid pathology in correlation with surgeons' experience in IONM (trained or untrained).

RESULTS

There were 2351 nerves at risk (NAR) and 39 RNLP were diagnosed after thyroid surgery (1.66%). Surgeons trained in IONM performed 52.2% of all operations (1200 NAR) with 7 RLNP (0.58%), whereas not-trained had 32 RLNP for 1151 NAR (2.8%; p < 0.001). After 182 thyroidectomies (357 NAR) guided by IONM (14.7%) 3 RLNP were observed (0.84%) vs. 36 palsies per 1994 NAR without IONM (1.81%; p = 0.189). The highest danger of RLNP was reported after reoperations and the lowest after subtotal thyroidectomies. We found no association between thyroid pathology and RLNP rate.

CONCLUSIONS

According to our study training in IONM decreases chances of RLNP especially during total or near total thyroidectomy.

[Contribution of neuromonitoring to the safety of tracheal extubation after total thyroidectomy. Prospective study with needle electrodes]

INTRODUCTION AND OBJECTIVES

Bilateral laryngeal paralysis cause serious respiratory complications. In thyroid surgery, neuromonitoring helps in identifying the recurrent laryngeal nerve, reports on its functioning at the end of surgery, supports decision making, and may reduce the risk of bilateral paralysis. Our objective was to estimate the influence of neuromonitoring in operative strategy and extubation safety in total thyroidectomy.

METHODS

A non-randomized prospective study was conducted on 210 patients undergoing total thyroidectomy (420 laryngeal nerves stimulated included). We collected qualitative neuromonitoring variables (presence or absence of final signal after stimulation of the vagus nerve), and postoperative indirect laryngoscopy (normal motility or paralysis), performed until 3rd day after the surgery.

RESULTS

The accuracy of the test was 99.5% (95% CI 98.3 to 99.9). The positive predictive value was 100% (95% CI 99.1 to 100), which showed the high ability of neuromonitoring to predict paralysis in case of loss of signal, and the negative predictive value was 99.5% (95% CI 98.3 to 99.9), which indicated its predictive capacity for normal motility when there is a normal signal.

CONCLUSIONS

In our group of patients, recurrent laryngeal nerve monitoring was useful in total thyroidectomy as it provided information on the prognosis of laryngeal motility, and helped in making decisions during surgery when there was signal loss. Due to the risk of serious respiratory complications due to bilateral recurrent laryngeal nerve paralysis, we opted for the performing of the 2-stage total thyroidectomy in case of signal loss in the first lobectomy. Thereby, neuromonitoring contributed to the safety of the airway in tracheal extubation, aiding in the prevention of a possible bilateral laryngeal paralysis.