Risk factors of paralysis and functional outcome after recurrent laryngeal nerve monitoring in thyroid surgery.
BACKGROUND
Recurrent laryngeal nerve monitoring (RLNM) has been suspected to reduce postoperative RLN paralysis (RLNP). However, functional outcome of RLNM in comparison with no nerve identification and visual nerve identification only has not been analyzed.


METHODS
Analysis of 16,448 consecutive multi-institutional operations resulted in 29,998 nerves at risk. Three groups of different RLN treatment were compared: group 1, no RLN identification; group 2, visual RLN identification; and group 3, visual RLN identification and electromyographic monitoring. RLNM was performed with a bipolar needle electrode that was placed through the cricothyroid ligament into the vocal muscle.


RESULTS
Risk factors for permanent RLNP were recurrent benign and malignant goiter (odds ratios, [ORs]), 4.7, and 6.7, respectively), primary surgery in thyroid malignancy (OR, 2.0), lobectomy (OR, 1.8), no nerve identification (OR, 1.4), low or medium volume hospital (OR, 1.3), and low volume surgeons (OR, 1.2).


CONCLUSIONS
Based on these data, visual nerve identification was identified to be the gold standard of RLN treatment in thyroid surgery. RLNM is a promising tool for nerve identification and protection in extended thyroid resection procedures. However, because of the overall low frequency of RLNP, no statistical difference compared with visual nerve identification only was reached in the setting of this study.
Dralle
Henning
H
Department of General, Visceral and Vascular Surgery, Klinikum Kröllwitz, University of Halle, Ernst-Grube-Strasse 40, D-06097 Halle, Germany.
Sekulla
Carsten
C
Haerting
Johannes
J
Timmermann
Wolfgang
W
Neumann
Hans Jürgen
HJ
Kruse
Eberhard
E
Grond
Stefan
S
Mühlig
Hans Peter
HP
Richter
Christian
C
Voss
Johannes
J
Thomusch
Oliver
O
Lippert
Hans
H
Gastinger
Ingo
I
Brauckhoff
Michael
M
Gimm
Oliver
O
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D004576:Electromyography; D005260:Female; D006042:Goiter / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D011446:Prospective Studies; D012008:Recurrence; D012009:Recurrent Laryngeal Nerve / Q000503:physiopathology*; D012086:Reoperation; D012307:Risk Factors; D013964:Thyroid Neoplasms / Q000601:surgery*; D013965:Thyroidectomy / Q000009:adverse effects / Q000379:methods*; D014826:Vocal Cord Paralysis / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology